Science.gov

Sample records for cross-country mtb marathon

  1. Cross-Country Skiing.

    ERIC Educational Resources Information Center

    Arnold, Guy E.

    1980-01-01

    The cross-country ski program offered at Clarkson College in New York is described, including a brief outline of the course, necessary equipment, and suggestions for developing a similar course at other campuses. (JMF)

  2. Cross-Country Skiing Today.

    ERIC Educational Resources Information Center

    Caldwell, John

    This book presents changes in cross country skiing which have taken place in the last several years and is directed toward both beginning and seasoned tour skiers. Discussed are the following topics: (1) the cross-country revolution (new fiberglass skis); (2) equipment (how to choose from the new waxless touring skis); (3) care of equipment; (4)…

  3. Teaching Cross-Country Skiing.

    ERIC Educational Resources Information Center

    Nelson, Jonathan E.

    1984-01-01

    Cross-country skiing instruction can be done both inside and outside the gymnasium. This article provides activities to be performed inside to prepare students for skiing. Outside organization techniques and drills are suggested. A list of common errors is given. (DF)

  4. The Dissertation Marathon

    ERIC Educational Resources Information Center

    Black, Ronald

    2012-01-01

    We all think of a marathon as a long-distance running event with an official distance of 42.195 kilometers (26 miles and 385 yards). Throughout time marathon runners have pursued their longest goals by allowing their body to adapt to the new stresses through training. Training for a marathon takes intense preparation, dedication and skill. It is…

  5. Cross-country skiing injuries and biomechanics.

    PubMed

    Renstrom, P; Johnson, R J

    1989-12-01

    Cross-country skiing exercises most of the joints, muscles and tendons in the body giving the skier an all around workout. This, in combination with a low incidence of injury, makes cross-country skiing an ideal recreational and competitive sport. The new skating techniques developed during the last decade have resulted in greater velocity. The maximum speed during the diagonal stride technique is 6 m/sec compared to 8 to 9 m/sec when skating and double poling. Top-level skiers today use strong and ultra light skis of fiberglass and graphite. The ski weight is less than 500g. Today's skating technique does not require any waxing and only the cambered portion of the ski is waxed when performing the diagonal stride. The preparation of the ski course has improved with the development of special track machines. This allows top-level skiers to reach 60 to 80 km/h on downhill slopes, which has resulted in an increased risk of injury. Because cross-country skiing takes place wherever snow is available, it is difficult to establish accurate injury rates in comparison to alpine skiing which is performed on very specialised terrain at ski areas. Studies estimate the cross-country ski injury rate in Sweden to be around 0.2 to 0.5 per thousand skier days. A prospective study of cross-country ski injuries conducted in Vermont revealed an injury rate of 0.72 per thousand skier days. 75% of the injuries sustained by members of the Swedish national cross-country ski team during 1983 and 1984 were overuse injuries while 25% resulted from trauma. The most common overuse injuries included medial-tibial stress syndrome, Achilles tendon problems and lower back pain. Most common among traumatic injuries were ankle ligament sprains and fractures, muscle ruptures, and knee ligament sprains. Shoulder dislocation, acromioclavicular separation and rotator cuff tears are not infrequent in cross-country skiing. Injuries to the ulnar collateral ligament of the metacarpal phalangeal joint of the

  6. Half-marathoners are younger and slower than marathoners.

    PubMed

    Knechtle, Beat; Nikolaidis, Pantelis T; Zingg, Matthias A; Rosemann, Thomas; Rüst, Christoph A

    2016-01-01

    Age and performance trends of elite and recreational marathoners are well investigated, but not for half-marathoners. We analysed age and performance trends in 508,108 age group runners (125,894 female and 328,430 male half-marathoners and 10,205 female and 43,489 male marathoners) competing between 1999 and 2014 in all flat half-marathons and marathons held in Switzerland using single linear regression analyses, mixed-effects regression analyses and analyses of variance. The number of women and men increased across years in both half-marathons and marathons. There were 12.3 times more female half-marathoners than female marathoners and 7.5 times more male half-marathoners than male marathoners. For both half-marathons and marathons, most of the female and male finishers were recorded in age group 40-44 years. In half-marathons, women (10.29 ± 3.03 km/h) were running 0.07 ± 0.06 km/h faster (p < 0.001) than men (10.22 ± 3.06 km/h). Also in marathon, women (14.77 ± 4.13 km/h) were running 0.28 ± 0.16 km/h faster (p < 0.001) than men (14.48 ± 4.07 km/h). In marathon, women (42.18 ± 10.63 years) were at the same age than men (42.06 ± 10.45 years) (p > 0.05). Also in half-marathon, women (41.40 ± 10.63 years) were at the same age than men (41.31 ± 10.30 years) (p > 0.05). However, women and men marathon runners were older than their counterpart half-marathon runners (p < 0.001). In summary, (1) more athletes competed in half-marathons than in marathons, (2) women were running faster than men, (3) half-marathoners were running slower than marathoners, and (4) half-marathoners were younger than marathoners. PMID:26844023

  7. Dashing through the Snow--On Cross-Country Skis.

    ERIC Educational Resources Information Center

    Lohr, Roger

    1988-01-01

    A discussion of factors to consider when developing a cross-country area for skiing includes consideration of the components of a successful cross-country operation and how the sport can be effectively promoted. (JD)

  8. Autonomous system for cross-country navigation

    NASA Astrophysics Data System (ADS)

    Stentz, Anthony; Brumitt, Barry L.; Coulter, R. C.; Kelly, Alonzo

    1993-05-01

    Autonomous cross-country navigation is essential for outdoor robots moving about in unstructured environments. Most existing systems use range sensors to determine the shape of the terrain, plan a trajectory that avoids obstacles, and then drive the trajectory. Performance has been limited by the range and accuracy of sensors, insufficient vehicle-terrain interaction models, and the availability of high-speed computers. As these elements improve, higher- speed navigation on rougher terrain becomes possible. We have developed a software system for autonomous navigation that provides for greater capability. The perception system supports a large braking distance by fusing multiple range images to build a map of the terrain in front of the vehicle. The system identifies range shadows and interpolates undersamples regions to account for rough terrain effects. The motion planner reduces computational complexity by investigating a minimum number of trajectories. Speeds along the trajectory are set to provide for dynamic stability. The entire system was tested in simulation, and a subset of the capability was demonstrated on a real vehicle. Results to date include a continuous 5.1 kilometer run across moderate terrain with obstacles. This paper begins with the applications, prior work, limitations, and current paradigms for autonomous cross-country navigation, and then describes our contribution to the area.

  9. Kinematics of cross-country ski racing.

    PubMed

    Bilodeau, B; Rundell, K W; Roy, B; Boulay, M R

    1996-01-01

    This study investigated the evolution of skiing velocity, cycle length, and cycle rate in elite and subelite skiers during cross-country ski races. Senior male cross-country skiers engaged respectively in a 30-km skating race (N = 34) or a 50-km classical race (N = 27) were videotaped as they skied two different sections of 30 m, a 7 degrees uphill, and a flat section. In the skating race, most skiers used the offset technique on uphill and the 2-skate on flat, while the preferred techniques during the classical race were the diagonal stride for uphill and double-poling on flat. Results demonstrated that faster skiers had longer cycle lengths than slower skiers except for the flat sections of the classical race. Cycle rate was not different between skiers of different performance levels in any circumstances or races. Decreased velocity observed during the second half of the skating race was almost entirely due to a decrease in cycle length. We conclude that slower athletes should emphasize extending cycle length during their technical training. Therefore, skiers should place an emphasis on strength and power training to increase their kick and pole pushes and enhance cycle length.

  10. Venous Thromboembolism and Marathon Athletes

    MedlinePlus

    ... Heart Association Cardiology Patient Page Venous Thromboembolism and Marathon Athletes Claire M. Hull and Julia A. Harris ... general adult population are indisputable. However, for the marathon athlete who trains intensively and for long periods ...

  11. Fitness Levels of University Cross-Country Skiers.

    ERIC Educational Resources Information Center

    Ruhling, Robert O.; Storer, Thomas W.

    Dry-land training in preparation for competitive cross-country skiing proved to be effective in increasing athletes' aerobic capacity and physical fitness. Such training included bicycle racing, roller skiing, fartlek running, cross-country running, simulated ski walking on inclines, and interval training over hills. (JD)

  12. A Guide to Equipment: Cross-Country Skiing.

    ERIC Educational Resources Information Center

    Gillette, Ned

    1980-01-01

    Discussed are guidelines for asking questions and selecting cross-country skis, boots, bindings, poles, and touring packs. To choose any type of cross-country gear, the strategy recommended is to match the equipment to the athelete's skiing style. (WB)

  13. Kick, Glide, Pole! Cross-Country Skiing Fun (Part II)

    ERIC Educational Resources Information Center

    Duoos, Bridget A.

    2012-01-01

    Part I of Kick, Glide, Pole! Cross-Country Skiing Fun, which was published in last issue, discussed how to select cross-country ski equipment, dress for the activity and the biomechanics of the diagonal stride. Part II focuses on teaching the diagonal stride technique and begins with a progression of indoor activities. Incorporating this fun,…

  14. Kick, Glide, Pole! Cross-Country Skiing Fun (Part I)

    ERIC Educational Resources Information Center

    Duoos, Bridget A.

    2011-01-01

    Cross-country skiing is a great activity for taking a physical education class outside during the cold winter months. It is also a diverse activity that appeals to students of all ages, and is an excellent cardio-respiratory activity to keep students active. This article has provided the first steps in preparing a cross-country skiing lesson in…

  15. Maximum Power Training and Plyometrics for Cross-Country Running.

    ERIC Educational Resources Information Center

    Ebben, William P.

    2001-01-01

    Provides a rationale for maximum power training and plyometrics as conditioning strategies for cross-country runners, examining: an evaluation of training methods (strength training and maximum power training and plyometrics); biomechanic and velocity specificity (role in preventing injury); and practical application of maximum power training and…

  16. Cross Country Skiing: Special Olympics Sports Skills Instructional Program.

    ERIC Educational Resources Information Center

    Joseph P. Kennedy, Jr. Foundation, Washington, DC.

    The last of five booklets on specific sports instruction in Special Olympics presents information on teaching cross country skiing to mentally retarded persons. The approach uses goals, short term objectives, task analyzed activities, assessments and teaching suggestions for individualizing and integrating the sports skills instruction with other…

  17. Cross-Country Evidence on Teacher Performance Pay

    ERIC Educational Resources Information Center

    Woessmann, Ludger

    2011-01-01

    The general-equilibrium effects of performance-related teacher pay include long-term incentive and teacher-sorting mechanisms that usually elude experimental studies but are captured in cross-country comparisons. Combining country-level performance-pay measures with rich PISA-2003 international achievement micro data, this paper estimates…

  18. Cross-Country Skiing Injuries and Training Methods.

    PubMed

    Nagle, Kyle B

    2015-01-01

    Cross-country skiing is a low injury-risk sport that has many health benefits and few long-term health risks. Some concern exists that cross-country skiing may be associated with a higher incidence of atrial fibrillation; however, mortality rates among skiers are lower than those among the general population. While continuing to emphasize aerobic and anaerobic training, training methods also should promote ski-specific strength training to increase maximum force and its rate of delivery and to build muscular endurance to maintain that power through a race. Multiple tests are available to monitor training progress. Which tests are most appropriate depends on the specific events targeted. In addition to laboratory-based tests, there also are many simpler, more cost-effective tests, such as short time trials, that can be used to monitor training progress and predict performance particularly at the junior skier level where access and cost may be more prohibitive. PMID:26561764

  19. Cross-Country Skiing Injuries and Training Methods.

    PubMed

    Nagle, Kyle B

    2015-01-01

    Cross-country skiing is a low injury-risk sport that has many health benefits and few long-term health risks. Some concern exists that cross-country skiing may be associated with a higher incidence of atrial fibrillation; however, mortality rates among skiers are lower than those among the general population. While continuing to emphasize aerobic and anaerobic training, training methods also should promote ski-specific strength training to increase maximum force and its rate of delivery and to build muscular endurance to maintain that power through a race. Multiple tests are available to monitor training progress. Which tests are most appropriate depends on the specific events targeted. In addition to laboratory-based tests, there also are many simpler, more cost-effective tests, such as short time trials, that can be used to monitor training progress and predict performance particularly at the junior skier level where access and cost may be more prohibitive.

  20. Crystalluria in marathon runners. 1. Standard marathon--males.

    PubMed

    Irving, R A; Noakes, T D; Rodgers, A L; Swartz, L

    1986-01-01

    Epidemiological evidence suggests that marathon runners have a higher incidence of renal stone formation than occurs in the general population. Since crystalluria and stone disease are thought to be related, we subjected urine samples from a group of marathon runners to particle counting and sizing in a Coulter Counter equipped with a population accessory unit. The volume-size distribution curves so obtained were bimodal with one peak occurring in the 2-5 micron diameter range and a second in the 15-32 micron diameter range - a pattern that is remarkably similar to the distributions reported for recurrent idiopathic stone formers and distinctly different to those recorded for control subjects. Analyses by scanning electron microscopy and X-ray powder diffraction revealed other features which are regarded as typical of stone formers' crystalluria. These physicochemical data indicate that marathon runners may be at increased risk of urinary stone formation.

  1. Amyotrophic lateral sclerosis among cross-country skiers in Sweden.

    PubMed

    Fang, Fang; Hållmarker, Ulf; James, Stefan; Ingre, Caroline; Michaëlsson, Karl; Ahlbom, Anders; Feychting, Maria

    2016-03-01

    A highly increased risk of amyotrophic lateral sclerosis (ALS) has been suggested among professional athletes. We aimed to examine whether long distance cross-country skiers have also a higher risk of ALS and whether the increased risk was modified by skiing performance. We followed 212,246 cross-country skiers in the Swedish Vasaloppet cohort and a random selection of 508,176 general Swedes not participating in the Vasaloppet during 1989-2010. The associations between cross-country skiing as well as skiing performance (i.e., type of race, finishing time and number of races) and the consequent risk of ALS were estimated through hazard ratios (HRs) derived from Cox model. During the study, 39 cases of ALS were ascertained among the skiers. The fastest skiers (100-150% of winner time) had more than fourfold risk of ALS (HR 4.31, 95% confidence interval [CI] 1.78-10.4), as compared to skiers that finished at >180% of winner time. Skiers who participated >4 races during this period had also a higher risk (HR 3.13, 95% CI 1.37-7.17) than those participated only one race. When compared to the non-skiers, the fastest skiers still had a higher risk (HR 2.08, 95% CI 1.12-3.84), as skiers who had >4 races (HR 1.88, 95% CI 1.05-3.35), but those finishing at >180% of winner time had a lower risk (HR 0.46, 95% CI 0.24-0.87). In conclusion, long distance cross-country skiing is associated with a higher risk of ALS, but only among the best skiers; recreational skiers appear to have a largely reduced risk.

  2. Dynamics of coordination in cross-country skiing.

    PubMed

    Cignetti, F; Schena, F; Zanone, P G; Rouard, A

    2009-04-01

    The aim of the present study was to identify modes of coordination in cross-country skiing from a dynamical systems perspective. Participants (N=8) skied on a treadmill using classical techniques with varying steepness (i.e., 0 degrees-7 degrees). Coordination was evaluated in terms of the relative frequency and relative phase between upper arms and thighs. Results revealed that the limb movements were systematically attracted towards low integer frequency ratios (i.e., 1:1 and 2:1) and in-phase (phi approximately 0 degrees ) and anti-phase relationships (phi approximately 180 degrees). The increase in steepness produced shifts between the attractive modes of limb movements and a loss of stability was observed during transitions. These results suggest that principles of coordination between limbs in cross-country skiing are akin to those of non-linear coupled oscillators, as documented for a broad range of motor activities. Yet, differences with such classical findings are discussed reflecting the specific biomechanical constraints of cross-country skiing.

  3. Transference of 3D accelerations during cross country mountain biking.

    PubMed

    Macdermid, Paul W; Fink, Philip W; Stannard, Stephen R

    2014-06-01

    Investigations into the work demands of Olympic format cross country mountain biking suggest an incongruent relationship between work done and physiological strain experienced by participants. A likely but unsubstantiated cause is the extra work demand of muscle damping of terrain/surface induced vibrations. The purpose of this study was to describe the relationship between vibration mechanics and their interaction with terrain, bicycle and rider during a race pace effort on a cross country mountain bike track, on both 26″ and 29″ wheels. Participants completed one lap of a cross country track using 26″ and 29″ wheels, at race pace. Power, cadence, speed, heart rate and geographical position were sampled and logged every second for control purposes. Tri-axial accelerometers located on the bicycle and rider, recorded accelerations (128Hz) and were used to quantify vibrations experienced during the whole lap and over terrain sections (uphill and downhill). While there were no differences in power output (p=0.3062) and heart rate (p=0.8423), time to complete the lap was significantly (p=0.0061) faster on the 29″ wheels despite increased vibrations in the larger wheels (p=0.0020). Overall accelerometer data (RMS) showed location differences (p<0.0001), specifically between the point of interface of bike-body compared to those experienced at the lower back and head. The reduction in accelerations at both the lower back and head are imperative for injury prevention and demonstrates an additional non-propulsive, muscular, challenge to riding. Stress was greatest during downhill sections as acceleration differences between locations were greater when compared to uphill sections, and thus possibly prevent the recovery processes that may occur during non-propulsive load.

  4. A study of course deviations during cross-country soaring

    NASA Technical Reports Server (NTRS)

    Sliwa, S. M.; Sliwa, D. J.

    1979-01-01

    Several models are developed for studying the impact of deviations from course during cross country soaring flights. Analyses are performed at the microstrategy and macrostrategy levels. Two types of lift sources are considered: concentrated thermals and thermal streets. The sensitivity of the optimum speed solutions to various model, piloting and performance parameters is evaluated. Guides are presented to provide the pilot with criterions for making in-flight decisions. In general, course deviations are warranted during weak lift conditions, but are less justifiable with moderate to strong lift conditions.

  5. Biomechanical analysis of cross-country skiing techniques.

    PubMed

    Smith, G A

    1992-09-01

    The development of new techniques for cross-country skiing based on skating movements has stimulated biomechanical research aimed at understanding the various movement patterns, the forces driving the motions, and the mechanical factors affecting performance. Research methods have evolved from two-dimensional kinematic descriptions of classic ski techniques to three-dimensional analyses involving measurement of the forces and energy relations of skating. While numerous skiing projects have been completed, most have focused on either the diagonal stride or the V1 skating technique on uphill terrain. Current understanding of skiing mechanics is not sufficiently complete to adequately assess and optimize an individual skier's technique.

  6. Marathon training and immune function.

    PubMed

    Nieman, David C

    2007-01-01

    Many components of the immune system exhibit adverse change after marathon-type exertion. These immune changes occur in several compartments of the immune system and body (e.g. the skin, upper respiratory tract mucosal tissue, lung, peritoneal cavity, blood and muscle). Of all immune cells, natural killer (NK) cells, neutrophils and macrophages (of the innate immune system) exhibit the greatest changes in response to marathon competition, both in terms of numbers and function. Many mechanisms appear to be involved, including exercise-induced changes in stress hormone and cytokine concentrations, body temperature changes, increases in blood flow and dehydration. During this 'open window' of immune dysfunction (which may last between 3 and 72 hours, depending on the immune measure), viruses and bacteria may gain a foothold, increasing the risk of subclinical and clinical infection. Of the various nutritional and pharmacological countermeasures to marathon-induced immune perturbations that have been evaluated thus far, ingestion of carbohydrate beverages during intense and prolonged exercise has emerged as the most effective. However, carbohydrate ingestion during a marathon attenuates increases in plasma cytokines and stress hormones, but is largely ineffective against changes in other immune components including suppression of NK and T-cell function, and salivary IgA output. Other countermeasures, such as glutamine, antioxidant supplements and ibuprofen, have had disappointing results and thus the search for companion agents to carbohydrate continues. PMID:17465622

  7. Characterization of Electrocardiogram Changes Throughout a Marathon

    PubMed Central

    Callaway, Clifton; Salcido, David; McEntire, Serina; Roth, Ronald; Hostler, David

    2014-01-01

    Purpose There are few data examining cardiovascular physiology throughout a marathon. This study was devised to characterize electrocardiographic activity continuously throughout a marathon. Methods Cardiac activity was recorded from 19 subjects wearing a Holter monitor during a marathon. The 19 subjects (14 men and 5 women) were aged 39 ± 16 years (mean ± SD) and completed a marathon in 4:32:16 ± 1:23:35. Heart rate (HR), heart rate variability (HRV), T-wave amplitude, T-wave amplitude variability, and T-wave alternans (TWA) were evaluated continuously throughout the marathon. Results Averaged across all subjects, HRV, T-wave amplitude variability, and TWA increased throughout the marathon. Increased variability in T-wave amplitude occurred in 86% of subjects, characterized by complex oscillatory patterns and TWA. Three minutes after the marathon, HR was elevated and HRV was suppressed relative to the pre-marathon state. Conclusion HRV and T-wave amplitude variability, especially in the form of TWA, increase throughout a marathon. Increasing TWA as a marathon progresses likely represents a physiologic process as no arrhythmias or cardiac events were observed. PMID:24832192

  8. Training for cross-country skiing and iron status.

    PubMed

    Haymes, E M; Puhl, J L; Temples, T E

    1986-04-01

    Effects of iron supplements and training for cross-country skiing on hematological and iron status were studied in nine men and ten women from the U. S. Nordic ski team. Four men and five women received a multiple vitamin, multiple mineral supplement containing 18 mg iron for 8 months while five men and five women received a placebo. Fasting blood samples were taken from all skiers prior to supplementation (May) and in August, November, and January. Hemoglobin, hematocrit, plasma iron, total iron binding capacity (TIBC), percentage of transferrin saturation, serum ferritin, free erythrocyte porphyrin, and haptoglobin were measured on each sample. Hemoglobin, hematocrit, and TIBC were higher in November when both men and women skiers trained at altitude than in August. In January TIBC was further increased, haptoglobin was increased, hemoglobin for the men fell below May levels, and hematocrit returned to May levels. Skiers receiving iron had lower TIBC levels in November and January than the placebo group. Six women and two men had ferritin levels below 28 ng X ml-1, which suggests prelatent iron deficiency. Free erythrocyte porphyrin levels above 100 micrograms X dl-1 RBC were found in all skiers at some point during training. The results suggest that multivitamin, multimineral supplements containing iron have little effect on the iron status of cross-country skiers.

  9. Preloading of the thrust phase in cross-country skiing.

    PubMed

    Komi, P V; Norman, R W

    1987-03-01

    Based on the assumption that the stretch-shortening cycle is a natural way of muscle function, the occurrence of such a cycle was investigated in a diagonal technique of cross-country skiing. Cinematographic, special force platform, and telemetered EMG techniques were employed. The four subjects studied were all elite international level cross-country skiers, and the measurements were taken either under world championship conditions (cinematography) or during special test situations outdoors (EMG, force platform, and cinematography). The skiing was performed on the fixed uphill course (competition) and on the variable uphill tracks (2.5 degrees-11 degrees). The latter condition allowed mounting of a special long force platform system under the track. The results indicated that the leg kick phase is preceded by a typical unweighting phase, which is followed by braking and propulsion phases. Angular velocity curves of the hip, knee, and ankle joints revealed indirectly the segmental occurrence of the stretch-shortening cycle. Similar phenomena could be identified for the elbow joint during the pole plant and thrust phases. On a steep uphill track, the muscle activation pattern and the ground reaction forces resembled in many instances those of slow level running. Based on the results, a model was suggested to describe how the preloading of the leg thrust phase takes place as a sequential flow from one joint to another.

  10. Physiological aspects of competitive cross-country skiing.

    PubMed

    Hoffman, M D; Clifford, P S

    1992-02-01

    The physiological demands of cross-country skiing require competitive skiers to have high maximal oxygen uptakes and anaerobic thresholds. Anaerobic capacity has a relatively less important role, but may be of greater importance today with the faster race velocities resulting from the new skiing techniques of ski skating. Although use of the ski skating techniques results in faster race velocities than the classical techniques, it has been found that under some conditions the double-pole technique is more economical than other skiing techniques. It is suggested that this results from a more effective storage and recovery of elastic energy, a greater proportion of the forces being directed along the line of travel, and a lower air resistance due to greater trunk and hip flexion with the double-pole technique. The greater economy of the double-pole technique suggests that this may be advantageous in certain race conditions if the upper body is adequately prepared. The greater propulsive forces generated with the upper body with ski skating also suggest that training of the upper body should receive more emphasis. The potential cardiovascular adaptations from cross-country ski training appear to be similar for the classical and skating techniques, yet training specificity is important for optimal performance.

  11. [Dynamic characteristics of alternate strides in cross-country skiing].

    PubMed

    Gagnon, M

    1980-03-01

    Seven instructors in cross-country skiing were filmed during the performance of the alternate stride at three different velocities: maximal, medium and slow. The dynamic characteristics of the movement were analyzed. On the basis of spatio-temporal analyses, it was found that the alternate stride is a motion essentially propulsive with the predominance of the superior limbs to propulsion. The skier maintains or increases his velocity at the beginning of the glide which is possibly attributed to the transfer of momentum of the recovery leg. A decrease in horizontal velocity is observed at the end of the glide. At maximal speed, the asynchronous character of the actions by the superior and inferior limbs is more important; there is a reduced emphasis in the actions by the superior limbs. At medium speed, the following characteristics are observed: a reduced importance in the asynchronous actions, a larger preponderance to the gliding phase and a smaller elevation of the skier's center of gravity.

  12. Cross-country skiing and postexercise heart-rate recovery.

    PubMed

    Mourot, Laurent; Fabre, Nicolas; Andersson, Erik; Willis, Sarah; Buchheit, Martin; Holmberg, Hans-Christer

    2015-01-01

    Postexercise heart-rate (HR) recovery (HRR) indices have been associated with running and cycling endurance-exercise performance. The current study was designed (1) to test whether such a relationship also exists in the case of cross-country skiing (XCS) and (2) to determine whether the magnitude of any such relationship is related to the intensity of exercise before obtaining HRR indices. Ten elite male cross-country skiers (mean ± SD; 28.2 ± 5.4 y, 181 ± 8 cm, 77.9 ± 9.4 kg, 69.5 ± 4.3 mL · min-1 · kg-1 maximal oxygen uptake [VO2max]) performed 2 sessions of roller-skiing on a treadmill: a 2 × 3-km time trial and the same 6-km at an imposed submaximal speed followed by a final 800-m time trial. VO2 and HR were monitored continuously, while HRR and blood lactate (BLa) were assessed during 2 min immediately after each 6-km and the 800-m time trial. The 6-km time-trial time was largely negatively correlated with VO2max and BLa. On the contrary, there was no clear correlation between the 800-m time-trial time and VO2, HR, or BLa. In addition, in no case was any clear correlation between any of the HRR indices and performance time or VO2max observed. These findings confirm that XCS performance is largely correlated with VO2max and the ability to tolerate high levels of BLa; however, postexercise HRR showed no clear association with performance. The homogeneity of the group of athletes involved and the contribution of the arms and upper body to the exercise preceding determination of HRR may explain this absence of a relationship.

  13. Myths and Concerns Re: The Marathon.

    ERIC Educational Resources Information Center

    Betz, Robert, L.

    The marathon is a specific form of the psycho-process cluster which has its own identifiable characteristics, the basic one being intensity. The primary objective in structuring the marathon is to intensify physical and emotional contact in order to precipitate, encourage, and accelerate the process of behavior change. Myths which have evolved…

  14. Effects of a Marathon Group Experience

    ERIC Educational Resources Information Center

    Treppa, Jerry A.; Fricke, Lawrence

    1972-01-01

    The present study examined the effects of a weekend marathon group experience on values of self-actualization and on the interpersonal dimnension of personality. Both experimental and control subjects showed significanly positive changes on posttest and follow-up scores. It was premature to believe that the positive effects of a marathon group…

  15. Marathon Writing--A Letter to Parents.

    ERIC Educational Resources Information Center

    McCoy, Linda Jones

    Based on a year's work with 16 second grade students, this two-part paper reports the successful use of the Marathon Writing (continuous writing for short periods on a regular basis) strategy in encouraging beginning writers to write independently. The first part of the paper explains the technique of marathon writing, and notes that even though…

  16. What band rocks the MTB? (Invited)

    NASA Astrophysics Data System (ADS)

    Kind, J.; García-Rubio, I.; Gehring, A. U.

    2013-12-01

    Magnetotactic bacteria (MTB) are a polyphyletic group of bacteria that have been found in marine and lacustrine environments and soils [e.g. 1]. The hallmark of MTB is their intracellular formation of magnetosomes, single-domain ferrimagnetic particles that are aligned in chains. The chain configuration generates a strong magnetic dipole, which is used as magnetic compass to move the MTB into their favorable habit. The term band corresponds to a frequency window of microwaves in the gigahertz (GHz) range. Ferromagnetic resonance (FMR) spectroscopy uses the microwave absorption in a magnetic field to analyze the anisotropy properties and the domain state of magnetic materials. Specific microwave frequency causes absorption in a characteristic magnetic field range. For the investigation of MTB we use S-band (4.02 GHz), X-band (9.47 GHz), and Q-band (34.16 GHz). Experiments on cultured MTB and on sediment samples of Holocene age showed that absorption in X- and Q-band occurs when the sample is in a saturated or nearly saturated state [2, 3]. By contrast, absorption in the S-band appears in lower magnetic fields, where the sample is far from saturation. All FMR spectra show two distinct low-field features that can be assigned to magnetite particles in chains, aligned parallel and perpendicular to the external magnetic field. The detailed separation of the parallel and perpendicular components in the bulk samples is hampered, because of the random orientation of the chains in the sample. The comparison of S-, X-, and Q-band shows that the lower the frequency the better the separation of the components. In the S-band FMR spectroscopy, the separation of chains parallel to the external magnetic field is supported by the internal field of the sample. This field is caused by the remanence that contributes to the external magnetic field to fulfill the resonance condition [3,4]. Considering the different FMR responses, it can be postulated that a lower microwave frequency

  17. Motor abilities and anthropometrics in youth cross-country skiing.

    PubMed

    Stöggl, R; Müller, E; Stöggl, T

    2015-02-01

    The purposes were to validate whether general motor abilities and anthropometrics are determinants of youth cross-country (XC) skiing performance; evaluate gender-specific differences; and to establish noninvasive diagnostics. Fifty-one youth XC skiers (34 boys; 13.8 ± 0.6 years and 17 girls; 13.4 ± 0.9 years) performed motor skill and laboratory tests, and anthropometric data were collected and correlated with XC skiing performance. Anthropometrics and maturity status were related to boys but not to girls XC skiing performance. Push-ups and 20-m sprint were correlated to XC skiing performance in both boys and girls. XC skiing performance of boys was predominantly influenced by upper body and trunk strength capacities (medicine ball throw, push-ups, and pull-ups) and jumping power (standing long and triple jump), whereas XC skiing of girls was mainly influenced by aerobic capacities (3000-m run). Laboratory measures did not reveal greater correlations to XC skiing performance compared with simple test concepts of speed, strength, and endurance. Maturity was a major confounding variable in boys but not girls. Use of noninvasive simple test concepts for determination of upper body strength, speed, and endurance represent practicable support for ski clubs, schools, or skiing federations in the guidance and evaluation of young talent, being aware of the effect of maturity especially in boys. PMID:24894129

  18. Biomechanical determinants of oxygen extraction during cross-country skiing.

    PubMed

    Stöggl, T; Björklund, G; Holmberg, H-C

    2013-02-01

    To determine the relationship of muscle activation, force production, and cycle characteristics to O(2) extraction during high- and lower-intensity double poling (DP), nine well-trained male cross-country skiers performed DP on a treadmill for 3 min at 90% VO(2peak) followed by 6 min at 70%. During the final minute at each workload, arterial, femoral, and subclavian venous blood were collected for determination of partial pressure of O(2), partial pressure of CO(2), pH, and lactate. Electromyography (EMG) was recorded from six upper and lower body muscles, leg and pole forces were measured, and cardiorespiratory variables were monitored continuously. O(2) extraction was associated with time point of peak pole force (PF(peak)), duration of recovery, EMG activity, and lower body use. Arm O(2) extraction was lower than in the legs at both intensities (P < 0.001) and was reduced to a lesser extent upon decreasing the workload (P < 0.05). Arm root-mean-square EMG was higher during the poling phase and entire cycle compared with the legs (P < 0.001). Blood lactate was higher in the subclavian than in femoral vein and artery (P < 0.001) and independent of intensity. O(2) extraction was correlated to low muscle activation, later PF(peak) , prolonged poling time, and extensive dynamic lower body use. Cycle rate and recovery time were associated with O(2) extraction during high-intensity exercise only.

  19. Motor abilities and anthropometrics in youth cross-country skiing.

    PubMed

    Stöggl, R; Müller, E; Stöggl, T

    2015-02-01

    The purposes were to validate whether general motor abilities and anthropometrics are determinants of youth cross-country (XC) skiing performance; evaluate gender-specific differences; and to establish noninvasive diagnostics. Fifty-one youth XC skiers (34 boys; 13.8 ± 0.6 years and 17 girls; 13.4 ± 0.9 years) performed motor skill and laboratory tests, and anthropometric data were collected and correlated with XC skiing performance. Anthropometrics and maturity status were related to boys but not to girls XC skiing performance. Push-ups and 20-m sprint were correlated to XC skiing performance in both boys and girls. XC skiing performance of boys was predominantly influenced by upper body and trunk strength capacities (medicine ball throw, push-ups, and pull-ups) and jumping power (standing long and triple jump), whereas XC skiing of girls was mainly influenced by aerobic capacities (3000-m run). Laboratory measures did not reveal greater correlations to XC skiing performance compared with simple test concepts of speed, strength, and endurance. Maturity was a major confounding variable in boys but not girls. Use of noninvasive simple test concepts for determination of upper body strength, speed, and endurance represent practicable support for ski clubs, schools, or skiing federations in the guidance and evaluation of young talent, being aware of the effect of maturity especially in boys.

  20. Subclassification of low back pain: a cross-country comparison.

    PubMed

    Billis, Evdokia V; McCarthy, Christopher J; Oldham, Jacqueline A

    2007-07-01

    Various health professionals have attempted to classify low back pain (LBP) subgroups and have developed several LBP classification systems. Knowing that culture has an effect on LBP symptomatology, assessment findings and clinical decision making, the aim of this review is to perform a cross-country comparative review amongst the published classification systems, addressing each country's similarities and differences as well as exploring whether cultural factors have been incorporated into the subclassification process. A systematic search of databases limited to human adults was undertaken by Medline, Cinahl, AMED and PEDro databases between January 1980 and October 2005. Classification systems from nine countries were identified. Most studies were classified according to pathoanatomic and/or clinical features, whereas fewer studies utilized a psychosocial and even less, a biopsychosocial approach. Most studies were limited in use to the country of the system's developer. Very few studies addressed cultural issues, highlighting the lack of information on the impact of specific cultural factors on LBP classification procedures. However, there seem to be certain 'cultural trends' in classification systems within each country, which are discussed. Despite the plethora of classification studies, there is still no system which is internationally established, effective, reliable and valid. Future research should aim to develop a LBP classification system within a well identified cultural setting, addressing the multi-dimensional features of the LBP presentation.

  1. Zipf rank approach and cross-country convergence of incomes

    NASA Astrophysics Data System (ADS)

    Shao, Jia; Ivanov, Plamen Ch.; Urošević, Branko; Stanley, H. Eugene; Podobnik, Boris

    2011-05-01

    We employ a concept popular in physics —the Zipf rank approach— in order to estimate the number of years that EU members would need in order to achieve "convergence" of their per capita incomes. Assuming that trends in the past twenty years continue to hold in the future, we find that after t≈30 years both developing and developed EU countries indexed by i will have comparable values of their per capita gross domestic product {\\cal G}_{i,t} . Besides the traditional Zipf rank approach we also propose a weighted Zipf rank method. In contrast to the EU block, on the world level the Zipf rank approach shows that, between 1960 and 2009, cross-country income differences increased over time. For a brief period during the 2007-2008 global economic crisis, at world level the {\\cal G}_{i,t} of richer countries declined more rapidly than the {\\cal G}_{i,t} of poorer countries, in contrast to EU where the {\\cal G}_{i,t} of developing EU countries declined faster than the {\\cal G}_{i,t} of developed EU countries, indicating that the recession interrupted the convergence between EU members. We propose a simple model of GDP evolution that accounts for the scaling we observe in the data.

  2. 14 CFR 61.93 - Solo cross-country flight requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Solo cross-country flight requirements. 61... Solo cross-country flight requirements. (a) General. (1) Except as provided in paragraph (b) of this section, a student pilot must meet the requirements of this section before— (i) Conducting a solo...

  3. 14 CFR 61.93 - Solo cross-country flight requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Solo cross-country flight requirements. 61... Solo cross-country flight requirements. (a) General. (1) Except as provided in paragraph (b) of this section, a student pilot must meet the requirements of this section before— (i) Conducting a solo...

  4. 14 CFR 61.93 - Solo cross-country flight requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Solo cross-country flight requirements. 61... Solo cross-country flight requirements. (a) General. (1) Except as provided in paragraph (b) of this section, a student pilot must meet the requirements of this section before— (i) Conducting a solo...

  5. 14 CFR 61.93 - Solo cross-country flight requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Solo cross-country flight requirements. 61... Solo cross-country flight requirements. (a) General. (1) Except as provided in paragraph (b) of this section, a student pilot must meet the requirements of this section before— (i) Conducting a solo...

  6. Marathon Group: A Six Month Followup

    ERIC Educational Resources Information Center

    Foulds, Melvin L.; And Others

    1970-01-01

    The results of this study suggest that marathon groups may be an effective method for fostering the process of personal growth and self actualization in relatively healthy, growth seeking college students. (Author)

  7. Predicting Marathon Time Using Exhaustive Graded Exercise Test in Marathon Runners.

    PubMed

    Till, Eloise S; Armstrong, Stuart A; Harris, Greg; Maloney, Stephen

    2016-02-01

    The study aimed to investigate the correlation between time on a treadmill test and exhaustion 2 weeks before a road marathon and the subsequent road marathon performance time (MPT). The study recruited 59 runners entered in the Melbourne 2012 marathon, Canberra 2013 marathon, and Gold Coast 2013 marathon. Forty runners completed both the graded exercise treadmill test to exhaustion and the 42.2 km marathon. Nineteen participants dropped out of the study due to illness, injury, or did not begin the treadmill test. A statistically significant correlation was found between treadmill time and MPT (adjusted R(2) = 0.447). Sex, weekly running duration (t = -1.58, p = 0.12), years of running (t = 1.10, p = 0.28), and age (t = 0.94, p = 0.36) did not statistically correlate with MPT. The relationship between the graded exercise test and MPT can be used to predict MPT using y = -3.85x + 351.57, where y is MPT and x is treadmill time. This is a simple, accessible, and cost-effective method to aid athletes in predicting their race time over 42.2 km. Prediction of marathon time in a simple and accessible manner was believed to be useful to the growing population of marathon runners around the world.

  8. Endocrine responses to marathon running.

    PubMed Central

    Semple, C G; Thomson, J A; Beastall, G H

    1985-01-01

    We have examined the hormone status of ten healthy adult males who completed the Glasgow marathon. Serum thyroxine, free thyroxine, triiodothyronine and thyroid stimulating hormone were unaffected by the exertion. Serum cortisol as well as other steroid hormones, androstenedione, dehydroepiandrosterone sulphate and oestradiol showed distinct rises (p less than 0.01) but serum testosterone fell significantly (p less than 0.01). There was no change in sex hormone binding globulin capacity but a significant fall in LH levels (p less than 0.05) accompanied the fall in serum testosterone. The mechanism of the fall in serum testosterone in this situation requires clarification but it is unlikely to have adverse consequences. Images p148-a p148-b p148-c PMID:4075064

  9. Empirical Study of Training and Performance in the Marathon

    ERIC Educational Resources Information Center

    Slovic, Paul

    1977-01-01

    Similar systematic relationships exist between personal characteristics, training, and performance on the marathon, regardless of whether they derive from differences among individuals participating in the same run or from differences within the same person in two separate marathons. (Author)

  10. Cardiac Risks Associated With Marathon Running

    PubMed Central

    Day, Sharlene M.; Thompson, Paul D.

    2010-01-01

    Context: A recent cluster of sudden cardiac deaths in marathon runners has attracted considerable media attention and evoked concern over the safety of long-distance running and competition. This review discusses the acute and potential long-term risks associated with marathon running and puts these into perspective with the many health benefits afforded by habitual vigorous exercise. Evidence Acquisition: Data sources included peer-reviewed publications from 1979 to January 2010 as identified via PubMed and popular media. Results: Marathon running is associated with a transient and low risk of sudden cardiac death. This risk appears to be even lower in women and is independent of marathon experience or the presence of previously reported symptoms. Most deaths are due to underlying coronary artery disease. The value of preparticipation screening is limited by its insensitivity and impracticality of widespread implementation. Appropriate preparation and deployment of trained medical personnel and availability of automatic external defibrillators are expected to have a major impact on survival from cardiac arrests during marathons. Cardiac biochemical and functional abnormalities are commonly observed transiently following completion of a marathon, although their clinical significance is unknown. Conclusions: Sudden cardiac deaths associated with marathon running are exceedingly rare events. Prevention should focus on recognition and investigation of prodromal symptoms, if present, and access to rapid defibrillation and trained medical personnel. The robust association of endurance running with improved quality of life and longevity underscores the importance of putting risks into perspective with other well-established health benefits of regular vigorous exercise. PMID:23015951

  11. Hematological Changes Following a Marathon Race in Males and Females.

    ERIC Educational Resources Information Center

    Wells, Christine L.; Mushabac, Lillian H.

    This study investigated the question of hemoconcentration-hemodilution and subsequent vascular fluid shifts evidenced by marathon runners. Blood samples were taken from runners before and after the New York City Marathon of 1978 and the Fiesta Bowl Marathon of the same year. Participants were of both sexes. Tables accompanying this report present…

  12. Increase in participation but decrease in performance in age group mountain marathoners in the 'Jungfrau Marathon': a Swiss phenomenon?

    PubMed

    Knechtle, Beat; Rosemann, Thomas; Zingg, Matthias A; Rüst, Christoph A

    2015-01-01

    Participation and performance trends for age group marathoners have been investigated for large city marathons such as the 'New York City Marathon' but not for mountain marathons. This study investigated participation and trends in performance and sex difference in the mountain marathon 'Jungfrau Marathon' held in Switzerland from 2000 to 2014 using single and mixed effects regression analyses. Results were compared to a city marathon (Lausanne Marathon) also held in Switzerland during the same period. Sex difference was calculated using the equation ([race time in women] - [race time in men]/[race time in men] × 100). Changes in sex differences across calendar years and were investigated using linear regression models. In 'Jungfrau Marathon', participation in all female and male age groups increased with exception of women in age groups 18-24 and men in age groups 30-34, 40-44 and 60-64 years where participation remained unchanged. In 'Lausanne Marathon', participation increased in women in age groups 30-34 to 40-44 years. In men, participation increased in age groups 25-29 to 44-44 years and 50-54 years. In 'Jungfrau Marathon' runners became slower across years in age groups 18-24 to 70-74 years. In 'Lausanne Marathon', runners became slower across years in age groups 18-24 and 30-34 to 65-69 years, but not for 25-29, 70-74 and 75-79 years. In 'Jungfrau Marathon', sex difference increased in age groups 25-29 (from 4 to 10 %) and 60-64 years (from 3 to 8 %) but decreased in age group 40-44 years (from 12 to 6 %). In 'Lausanne Marathon', the sex difference showed no changes. In summary, participation increased in most female and male age groups but performance decreased in most age groups for both the mountain marathon 'Jungfrau Marathon' and the city marathon 'Lausanne Marathon'. The sex differences were lower in the 'Jungfrau Marathon' (~6-7 %) compared to the 'Lausanne Marathon' where the sex difference was ~10-12 % from age groups 18-24 to 55

  13. Marathon run: cardiovascular adaptation and cardiovascular risk.

    PubMed

    Predel, Hans-Georg

    2014-11-21

    The first marathon run as an athletic event took place in the context of the Olympic Games in 1896 in Athens, Greece. Today, participation in a 'marathon run' has become a global phenomenon attracting young professional athletes as well as millions of mainly middle-aged amateur athletes worldwide each year. One of the main motives for these amateur marathon runners is the expectation that endurance exercise (EE) delivers profound beneficial health effects. However, with respect to the cardiovascular system, a controversial debate has emerged whether the marathon run itself is healthy or potentially harmful to the cardiovascular system, especially in middle-aged non-elite male amateur runners. In this cohort, exercise-induced increases in cardiac biomarkers-troponin and brain natriuretic peptide-and acute functional cardiac alterations have been observed and interpreted as potential cardiac damage. Furthermore, in the cohort of 40- to 65-year-old males engaged in intensive EE, a significant risk for the development of atrial fibrillation has been identified. Fortunately, recent studies demonstrated a normalization of the cardiac biomarkers and the functional alterations within a short time frame. Therefore, these alterations may be perceived as physiological myocardial reactions to the strenuous exercise and the term 'cardiac fatigue' has been coined. This interpretation is supported by a recent analysis of 10.9 million marathon runners demonstrating that there was no significantly increased overall risk of cardiac arrest during long-distance running races. In conclusion, intensive and long-lasting EE, e.g. running a full-distance Marathon, results in high cardiovascular strain whose clinical relevance especially for middle-aged and older athletes is unclear and remains a matter of controversy. Furthermore, there is a need for evidence-based recommendations with respect to medical screening and training strategies especially in male amateur runners over the age of

  14. Rectal temperature after marathon running.

    PubMed Central

    Maughan, R J; Leiper, J B; Thompson, J

    1985-01-01

    Rectal temperature was measured in 62 male runners who competed in the 1983 Dundee marathon race: all measurements were made immediately after the race. Competitors' times were noted at 5, 10, 15 and 20 miles (8.0, 16.1, 24.1, 32.2 km) and at the finish (26.2 miles, 42.2 km). Mean finishing time of the group was 3 hr 33 min +/- 48 min (mean +/- S.D.; range = 2 hr 17 min-5 hr 11 min). Mean running speed of the group decreased progressively as the distance covered increased. Mean post-race rectal temperature was 38.7 +/- 0.9 degrees C (range 35.6-40.3 degrees C). The post-race temperature was correlated (p less than 0.01) with the time taken to cover the last 6.2 miles (10 km) of the race, but not with the overall finishing time (p greater than 0.05). Only the fastest runners were able to maintain an approximately constant pace throughout the race, whereas the slower runners slowed down progressively. The runners with the highest post-race temperature, although not necessarily the fastest runners, also tended to maintain a steady pace throughout. The runners with the lowest post-race temperature slowed down markedly only over the last 6.2 mile section of the race. The results clearly indicate that runners forced by fatigue or injury to slow down in the latter stages of races held at low ambient temperatures may already be hypothermic or at serious risk of hypothermia. Images p192-a p192-b p192-c PMID:4092138

  15. Skiing economy and efficiency in recreational and elite cross-country skiers.

    PubMed

    Ainegren, Mats; Carlsson, Peter; Tinnsten, Mats; Laaksonen, Marko S

    2013-05-01

    The purpose of this study was to investigate and compare skiing economy and gross efficiency in cross-country skiers of different performance levels, ages and genders; male recreational skiers and elite senior and junior cross-country skiers of both genders. The skiers performed tests involving roller skiing on a treadmill using the gear 3 and diagonal stride techniques. The elite cross-country skiers were found to have better skiing economy and higher gross efficiency (5-18%) compared with the recreational skiers (p < 0.05) and the senior elite had better economy and higher efficiency (4-5%) than their junior counterparts (p < 0.05), whereas no differences could be found between the genders. Also, large ranges in economy and gross efficiency were found in all groups. It was concluded that, in addition to V[Combining Dot Above]O2peak, skiing economy and gross efficiency have a great influence on the differences in performance times between recreational and junior and senior elite cross-country skiers, as well as between individual skiers within the different categories. Thus, we recommend cross-country skiers at all performance levels to test not only V[Combining Dot Above]O2peak, but also skiing economy and efficiency.

  16. Marathon Group Therapy with Former Drug Users.

    ERIC Educational Resources Information Center

    Page, Richard C.; Mannion, John

    1980-01-01

    Discusses the effects of marathon group therapy on attitudes of former drug users in a residential drug treatment center. Experimental group members responded higher on the group counseling evaluative subscale and lower on the guilt evaluative subscale than control members. (Author)

  17. Behavior Change Outcomes of Marathon Group Treatment

    ERIC Educational Resources Information Center

    Uhlemann, Max R.; Weigel, Richard G.

    1977-01-01

    This study evaluated behavior change occurring after a marathon group experience, with a focus on individualized rather than shared behavioral change criteria. The individualization of behavior change criteria is based on the assertion that few, if any, single change criteria are appropriate or realistic for assessing change in all individuals.…

  18. Marathon Group: Facilitator of Personal Growth?

    ERIC Educational Resources Information Center

    Guinan, James F.; Foulds, Melvin L.

    1970-01-01

    This is a report of changes on scales of the Personal Orientation Inventory following a marathon experience. Pretest and posttest results indicated changes in scores of an experimental group on those scales: Inner Direction, Existentiality, Feeling Reactivity, Spontaneity, Self Acceptance, Acceptance of Aggression, Capacity for Intimate Contact.…

  19. The Marathon Group Hypothesis: An Unanswered Question

    ERIC Educational Resources Information Center

    Marks, Stephen E.; And Others

    1973-01-01

    The authors of this article contend that the Guinan and Foulds study was inadequately designed and executed, and the results indicate little of the "usefulness" of the test, much less illuminate the important hypothesis central to the investigation. Specific suggestions for further research in marathon group evaluation are made. (Author)

  20. Marathon Group Therapy with Female Narcotic Addicts.

    ERIC Educational Resources Information Center

    Kilmann, Peter R.

    This study evaluated the impact of structured and unstructured marathon therapy on institutionalized female narcotic addicts. Subjects were randomly assigned to one of five groups: two structured therapy groups, two unstructured therapy groups, and a no-treatment control group. The Personal Orientation Inventory, the Adjective Check List, and a…

  1. Convection-diffusion effects in marathon race dynamics

    NASA Astrophysics Data System (ADS)

    Rodriguez, E.; Espinosa-Paredes, G.; Alvarez-Ramirez, J.

    2014-01-01

    In the face of the recent terrorist attack event on the 2013 Boston Marathon, the increasing participation of recreational runners in large marathon races has imposed important logistical and safety issues for organizers and city authorities. An accurate understanding of the dynamics of the marathon pack along the race course can provide important insights for improving safety and performance of these events. On the other hand, marathon races can be seen as a model of pedestrian movement under confined conditions. This work used data of the 2011 Chicago Marathon event for modeling the dynamics of the marathon pack from the corral zone to the finish line. By considering the marathon pack as a set of particles moving along the race course, the dynamics are modeled as a convection-diffusion partial differential equation with position-dependent mean velocity and diffusion coefficient. A least-squares problem is posed and solved with optimization techniques for fitting field data from the 2011 Chicago Marathon. It was obtained that the mean pack velocity decreases while the diffusion coefficient increases with distance. This means that the dispersion rate of the initially compact marathon pack increases as the marathon race evolves along the race course.

  2. Altitude is positively correlated to race time during the marathon.

    PubMed

    Lara, Beatriz; Salinero, Juan José; Del Coso, Juan

    2014-04-01

    Completing a marathon (42.2 km) is one of the more challenging sports activities. Besides the distance, the ambient conditions of the race (altitude, temperature, etc) can increase the physiological demands of the event. The purpose of this study was to investigate the relation between the altitude of the city in which the marathon is held and the marathon race time. For this purpose, we sought the race times of 16 popular marathons performed at different altitudes above sea level (range from ≈0 to 2800 meters above sea level). In these competitions, we analyzed the race times of the female and male runners who finished from 21(st) to 100(th) position. We excluded the top 20 male and female finishers from the analysis because elite athletes usually compete in marathons held at low altitudes above sea level. Ambient temperature, the positive cumulative elevation gain, and the number of participants were used as control variables. Finishing time in the marathon was positively correlated with the altitude of the competition for both male (r=0.78; p<0.05) and female participants (r=0.73; p<0.05). On average, each increase of 1000 meters above sea level augmented marathon race time by 10.8±0.6% in men and 12.3±0.7% in women. Compared to race times in the Rotterdam marathon (held at 0 meters above sea level), the time taken to complete the marathon was significantly higher in competitions held at an altitude of over 700 meters. In conclusion, the time taken to complete a marathon strongly depends on the altitude of the city in which the marathon is held. Selecting marathon competitions close to 0 m above sea level is a good strategy to maximize marathon performance.

  3. Measuring Statistics Anxiety: Cross-Country Validity of the Statistical Anxiety Scale (SAS)

    ERIC Educational Resources Information Center

    Chiesi, Francesca; Primi, Caterina; Carmona, Jose

    2011-01-01

    The aim of the research was to test the psychometric properties of the Italian version of the Vigil-Colet et al.'s Statistical Anxiety Scale (SAS), taking into account evidences based on (a) internal structure (factorial structure and cross-country invariance) and (b) relationships to other variables (the statistics anxiety's nomological network).…

  4. Educational Attainment and HIV/AIDS Prevalence: A Cross-Country Study

    ERIC Educational Resources Information Center

    Lakhanpal, Manisha; Ram, Rati

    2008-01-01

    Using data for a large cross-country sample, a reasonable model is estimated to judge the effect of adult educational attainment on prevalence of HIV. Three main points are noted. First, there is an indication of a significantly negative effect of educational attainment on HIV prevalence. Second, magnitude of the impact appears sizable. Third, a…

  5. Identifying Social Trust in Cross-Country Analysis: Do We Really Measure the Same?

    ERIC Educational Resources Information Center

    Torpe, Lars; Lolle, Henrik

    2011-01-01

    Many see trust as an important social resource for the welfare of individuals as well as nations. It is therefore important to be able to identify trust and explain its sources. Cross-country survey analysis has been an important tool in this respect, and often one single variable is used to identify social trust understood as trust in strangers,…

  6. Characteristics of the Female Athlete Triad in Collegiate Cross-Country Runners

    ERIC Educational Resources Information Center

    Thompson, Sharon H.

    2007-01-01

    The Female Athlete Triad is a life-threatening syndrome defined by disordered eating, amenorrhea, and osteoporosis. Objective and Participants: The author's purpose in this study was to examine female cross-country runners' (N = 300) calcium consumption, along with the prevalence of 2 components of the triad: disordered eating and menstrual…

  7. Measuring Youth Development: A Nonparametric Cross-Country "Youth Welfare Index"

    ERIC Educational Resources Information Center

    Chaaban, Jad M.

    2009-01-01

    This paper develops an empirical methodology for the construction of a synthetic multi-dimensional cross-country comparison of the performance of governments around the world in improving the livelihood of their younger population. The devised "Youth Welfare Index" is based on the nonparametric Data Envelopment Analysis (DEA) methodology and…

  8. Cross-Country Conversations: Techniques for Facilitating Web-Based Collaboration.

    ERIC Educational Resources Information Center

    Reinhart, Julie; Slowinski, Joe; Anderson, Tiffany

    This paper describes an online collaborative process among three university classes in a cross-country project. Two of the classes were undergraduate courses at the Indiana University Bloomington and Northwest campuses, and the third was a graduate course at North Carolina A & T State University. Each course was a traditional campus-based course…

  9. 14 CFR 61.111 - Cross-country flights: Pilots based on small islands.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... small islands. 61.111 Section 61.111 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... INSTRUCTORS Private Pilots § 61.111 Cross-country flights: Pilots based on small islands. (a) Except as provided in paragraph (b) of this section, an applicant located on an island from which the...

  10. 14 CFR 61.111 - Cross-country flights: Pilots based on small islands.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... small islands. 61.111 Section 61.111 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... INSTRUCTORS Private Pilots § 61.111 Cross-country flights: Pilots based on small islands. (a) Except as provided in paragraph (b) of this section, an applicant located on an island from which the...

  11. Comparing Efficiency in a Cross-Country Perspective: The Case of Italian and Spanish State Universities

    ERIC Educational Resources Information Center

    Agasisti, Tommaso; Perez-Esparrells, Carmen

    2010-01-01

    The growing internationalization of European Higher Education requires more emphasis on cross-country comparisons. In this paper, an efficiency analysis of Italian and Spanish universities is conducted; as well as from a comparative perspective. The efficiency scores are obtained using data envelopment analysis. The results demonstrate a good…

  12. 14 CFR 61.93 - Solo cross-country flight requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and model aircraft to be flown. (e) Maneuvers and procedures for cross-country flight training in a... on the maneuvers and procedures of this section that are appropriate to the make and model of... this part in the make and model of aircraft or similar make and model of aircraft for which solo...

  13. Perceived Conflict between Urban Cross-Country Skiers and Snowmobilers in Alberta.

    ERIC Educational Resources Information Center

    Jackson, Edgar L.; Wong, Robert A. G.

    1982-01-01

    Three indicators of the perceived conflict between urban cross-country skiers and snowmobilers in Alberta show that the conflict is asymmetrical. Skiers perceive snowmobilers as interfering negatively with their activity, while snowmobilers enjoy or are indifferent to meeting skiers. (Authors/JN)

  14. Development of upper body power in junior cross-country skiers.

    PubMed

    Nesser, Tom W; Chen, Shuping; Serfass, Robert C; Gaskill, Steven E

    2004-02-01

    With the advent of the ski-skating technique, upper body power has increasingly been shown to be a major factor in cross-country skiing success. The purpose of this study was to evaluate 4 commonly used training methods (weight, circuit, rollerboard, and ski-specific training) for the development of upper body power (UBP) in junior cross-country skiers. Fifty-eight adolescent cross-country skiers (Boys: n = 29, age = 16.0 +/- 1.2 y and Girls: n = 29, age = 15.5 +/- 1.5 y) were assigned to one of the UBP training methods for a 10-week training program. Fourteen cross-country runners served as controls (boys: n = 7, age = 15.8 +/- 1.7 y; girls: n = 7, age = 14.9 +/- 1.3 y). Skiers were evaluated pre- and post-training for upper body strength (UBS) using a 10 repetition maximum (RM) rollerboard test, for UBP using a double-poling ergometer and for upper body endurance (UBE) with a 3-km, arms-only, rollerski endurance time trial. Competitive race results were collected during the winters before and after training as were all training data. Only the rollerboard training group improved significantly greater than the control group (p < 0.05) in UBP and UBS. Improvements in UBP, UPS, and UBE were significantly related (r = 0.545, 0.303, and 0.407, respectively) to improvements in competitive performance. These data suggest that training using a rollerboard with 5-12RM and explosive speed is more effective in developing UBP than other common training methods for adolescent cross-country skiers. The practical importance of these data was verified by the significant relationships between improvements in UBP, UBS, and UBE related to improvements in competitive race performance.

  15. Crystalluria in marathon runners. II. Ultra-marathon--males and females.

    PubMed

    Rodgers, A L; Greyling, K G; Irving, R A; Noakes, T D

    1988-01-01

    Particle-volume size distribution curves for the urines of a group of male ultra-marathon runners have been recorded and show the same features as those reported in an earlier study involving standard marathon runners. It is again suggested that these features indicate risk of urinary stone formation although this does not appear to be increased by the more stressful ultra-marathon. Distribution curves obtained for female runners closely resemble those recorded for controls, thus rendering it impossible to assess their risk profile. A commonly observed feature of both the male and female urines was the presence of various urinary salts. Profuse calcium oxalate dihydrate crystals were detected in some samples 11 days after the race. It is suggested that entrapment sites within the urinary tract have a selective specificity for these crystals while urinary salts pass through unhindered.

  16. Effects of speed on temporal patterns in classical style and freestyle cross-country skiing.

    PubMed

    Nilsson, Johnny; Tveit, Per; Eikrehagen, Olav

    2004-01-01

    The purpose was to study the adaptation to speed in the temporal patterns of the movement cycle and determine any differences in velocity, cycle rate and cycle length at the maximum speed level in the different classical style and freestyle cross-country skiing techniques. Eight skilled male cross-country skiers were filmed with a digital video camera in the sagittal plane while skiing on a flat cross-country ski track. The skiers performed three classical style techniques the diagonal stride, kick double poling and the double poling technique and four freestyle techniques paddle dance (gear 2), double dance (gear 3), single dance (gear 4) and combiskate (gear 5) at four different self-selected speed levels slow, medium, fast and their maximum. Cycle duration, cycle rate, cycle length, and relative and absolute cycle phase duration of the different techniques at the different speed levels were analysed by means of a video analysis system. The cycle rate in all tested classical and freestyle techniques was found to increase significantly (p < .01) with speed from slow to maximum. Simultaneously, there was a significant decrease in the absolute phase durations of all the investigated skiing techniques. A minor, not significant, change in cycle length, and the significant increase in cycle rate with speed showed that the classical and freestyle cross-country skiing styles are dependent, to a large extent, on an increase in cycle rate for speed adaptation. A striking finding was the constant relative phase duration with speed, which indicates a simplified neural control of the speed adaptation in both cross-country skiing styles. For the practitioner, the knowledge about the importance of increasing cycle frequency rather than cycle length in the speed adaptation can be used to optimise a rapid increase in speed. The knowledge about the decrease in absolute phase duration, especially the thrust phase duration, points to the need for strength and technique training to

  17. Marathon Group Therapy: Potential for University Counseling Centers and Beyond

    ERIC Educational Resources Information Center

    Stanger, Thomas; Harris, Rafael S., Jr.

    2005-01-01

    A descriptive analysis of marathon group therapy was conducted, specifying issues of set-up, screening, preparation, start-up, introduction to group process, facilitating therapeutic moments throughout the weekend, termination, and follow-up. Factors and dynamics unique to this modality are outlined for marathon groups in university counseling…

  18. Self-Actualization Effects Of A Marathon Growth Group

    ERIC Educational Resources Information Center

    Jones, Dorothy S.; Medvene, Arnold M.

    1975-01-01

    This study examined the effects of a marathon group experience on university student's level of self-actualization two days and six weeks after the experience. Gains in self-actualization as a result of marathon group participation depended upon an individual's level of ego strength upon entering the group. (Author)

  19. An Age and Body Mass Handicap for the Marathon

    ERIC Educational Resources Information Center

    Vanderburgh, Paul M.

    2015-01-01

    An age and body mass handicap has been previously developed and validated for the 5-kilometer (5K) run. The purpose of this study was to develop a similar handicap for the marathon but with a different age adjustment based on deviations from age group world best marathon times within each sex. The resulting handicap allowed finish time comparisons…

  20. Mathematical simulation of energy expenditure and recovery during sprint cross-country skiing

    PubMed Central

    Moxnes, John F; Moxnes, Eldbjørg Dirdal

    2014-01-01

    Purpose A cross-country sprint competition relies on maximal effort durations of 3–4 minutes. Significant anaerobic energy contribution is expected. Anaerobic energy contribution has been estimated in different sports to date from the accumulated O2 deficit. However, the O2-deficit model can be questioned. We investigate anaerobic energy contribution by applying other methods than the O2 deficit. Methods Theoretical model development. Results For sprint cross-country competitions, the anaerobic energy contribution was 20%–25% independent of the employed mathematical model. Recovery times of a minimum 20 minutes were found to be required after sprint races to be sure that the performance in subsequent heats was not influenced. Conclusion The O2-deficit model gave anaerobic energy results in agreement with other models from the literature. Recovery times of a minimum 20 minutes were found to be required after sprint races to be sure that the performance in subsequent heats was not influenced. PMID:24966703

  1. One-dimensional V-Scope analysis of habituation to simulated cross-country skiing.

    PubMed

    Candler, P D; Li, J C; Tipler, B J

    1995-07-01

    Responses to simulated cross-country skiing were measured using the V-Scope, a new telemetric ultrasound motion monitor. Ten young male adults performed a total of 45 minutes of distributed practice on a Nordic-Track ski simulator. Over a period of three 15-minute sessions cadence and velocity were unchanged. Step and stride lengths decreased significantly (p < 0.05) after the first 15-minute session and then remained unchanged. There were no left-right limb differences across all sessions indicating a normal gait. Response variability in velocity, step lengths and stride length was dramatically reduced after the first exposure period. This study demonstrates that the V-Scope system is a useful motion analysing device and, on the basis of the data presented in this preliminary investigation, at least two 15-minute habituation sessions are required for initial habituation to simulated cross-country skiing.

  2. The elite cross-country skier provides unique insights into human exercise physiology.

    PubMed

    Holmberg, H-C

    2015-12-01

    Successful cross-country skiing, one of the most demanding of endurance sports, involves considerable physiological challenges posed by the combined upper- and lower-body effort of varying intensity and duration, on hilly terrain, often at moderate altitude and in a cold environment. Over the years, this unique sport has helped physiologists gain novel insights into the limits of human performance and regulatory capacity. There is a long-standing tradition of researchers in this field working together with coaches and athletes to improve training routines, monitor progress, and refine skiing techniques. This review summarizes research on elite cross-country skiers, with special emphasis on the studies initiated by Professor Bengt Saltin. He often employed exercise as a means to learn more about the human body, successfully engaging elite endurance athletes to improve our understanding of the demands, characteristics, and specific effects associated with different types of exercise.

  3. Racing performance and incremental double poling test on treadmill in elite female cross-country skiers.

    PubMed

    Fabre, Nicolas; Balestreri, Filippo; Leonardi, Allesandro; Schena, Fedrico

    2010-02-01

    The national Italian cross-country ski team has been evaluated on the basis of a new double poling cross-country roller skiing incremental test to exhaustion (DP) on a motorized driven treadmill. To verify the capacity of this specific test to predict performance, peak oxygen uptake (VO2peak), oxygen uptake at anaerobic threshold (VO2Th), peak treadmill speed, and treadmill speed at anaerobic threshold (Speak and STh, respectively) were measured during the test and correlated with the level of performance of 10 world class Italian female cross-country skiers. The physiological data obtained were also compared with results of an incremental and maximal test carried out by the same athletes but with the diagonal stride (DS) technique. Peak heart rate (HRpeak), HRTh, and VO2Th were significantly higher during DS than during DP (p < 0.001 for HRpeak and heart rate at anaerobic threshold (HRTh) p < 0.05 for VO2Th), whereas no difference was observed for VO2Thpeak. Speak and VO2peak were significantly correlated to FISI points only during DP (r = -0.88, p < 0.001 and r = -0.77, p < 0.01, respectively). STh and VO2Th during DP and VO2Th during DS were correlated with the level of performance (r = -0.88, p < 0.001; r = -0.63, p < 0.05; and r = -0.65, p < 0.05, respectively). Finally, VO2peak DP/VO2peak DS ratio was also correlated to the performance (r = -0.77, p < 0.01). On the other hand, no peak value achieved during DS was correlated with the level of performance. Based on these physiological results, this incremental DP test to exhaustion appears like a good predictor of elite cross-country skiers' performance.

  4. Wing shape optimization for maximum cross-country speed, with mathematical programming

    NASA Technical Reports Server (NTRS)

    Helwig, G.

    1979-01-01

    A computer program was developed to calculate numerically the speed and circling polars of an aircraft when the lift and drag characteristics of the wing airfoils are known. The planform of the wing is described by variables which are optimized so that the cross-country speed of the glider is maximum for the particular type of thermal model. Two thermal models are compared and shown that with a greater wing area than now normally used the performance can be increased.

  5. Comprehensive Sports Medicine Treatment of an Athlete Who Runs Cross-Country and is Iron Deficient

    PubMed Central

    McIntosh, Linda; Rutt, Richard

    2009-01-01

    Background Optimal athletic performance may be dependent upon an athlete maintaining adequate iron levels through the consumption of dietary forms of iron and subsequent metabolism. Endurance athletes, especially female distance runners, have been identified as being at risk for developing iron deficiency. While iron deficiency is treatable, early diagnosis may be delayed if an adequate medical history and evaluation is not conducted. Objective To describe the evaluation, diagnosis, and comprehensive sports medicine treatment of a collegiate cross-country athlete with a medical diagnosis of iron deficiency with anemia and sports-related musculoskeletal pain. Case Description A 21-year-old female collegiate cross-country athlete experienced a decline in her running performance beginning her freshman year of school. She continued to experience degradation in sports performance despite medical intervention. Two-and-a-half years after initially seeking medical attention she was diagnosed with iron deficiency with anemia by a primary care medical doctor. Additionally, the subject required rehabilitation due to the onset of sports-related musculoskeletal symptoms. Outcomes Comprehensive treatment for this patient consisted of iron supplementation, therapeutic exercises, manual therapy, and modalities. The athlete was able to compete during her entire cross-country season and earn All-American status at the Division-III level. Discussion Sports medicine professionals must consider iron deficiency as a possible differential diagnosis when evaluating endurance athletes. Subtle signs of iron deficiency may, unfortunately, be overlooked ultimately delaying treatment. PMID:21509116

  6. Quadrupedal Locomotion-Respiration Entrainment and Metabolic Economy in Cross-Country Skiers.

    PubMed

    Boldt, Kevin; Killick, Anthony; Herzog, Walter

    2016-02-01

    A 1:1 locomotion-respiration entrainment is observed in galloping quadrupeds, and is thought to improve running economy. However, this has not been tested directly in animals, as animals cannot voluntarily disrupt this entrainment. The purpose of this study was to evaluate metabolic economy in a human gait involving all four limbs, cross-country skiing, in natural entrainment and forced nonentrainment. Nine elite cross-country skiers roller skied at constant speed using the 2-skate technique. In the first and last conditions, athletes used the natural entrained breathing pattern: inhaling with arm recovery and exhaling with arm propulsion, and in the second condition, the athletes disentrained their breathing pattern. The rate of oxygen uptake (VO2) and metabolic rate (MR) were measured via expired gas analysis. Propulsive forces were measured with instrumented skis and poles. VO2 and MR increased by 4% and 5% respectively when skiers used the disentrained compared with the entrained breathing pattern. There were no differences in ski or pole forces or in timing of the gait cycle between conditions. We conclude that breathing entrainment reduces metabolic cost of cross-country skiing by approximately 4%. Further, this reduction is likely a result of the entrainment rather than alterations in gait mechanics.

  7. Muscle activation characteristics in cross-country skiers with a history of anterior compartment pain.

    PubMed

    Federolf, Peter; Bakker, Emily

    2012-11-01

    A large proportion of elite cross-country skiers suffer from chronic anterior compartment syndrome (CACS). This study used surface electromyograms (EMGs) to investigate whether differences existed in the activation characteristics of the tibialis anterior muscle between elite cross-country skiers with a history of anterior compartment pain (symptomatic group) and a pain-free control group. Based on self-reported pain symptoms, twelve young, national-level cross-country ski athletes were assigned to a symptomatic group (N = 5), a control group (N = 4), or analyzed individually if their diagnosis was not certain (N = 3). During skating, EMGs were recorded on five lower leg muscles. The relative increase in EMG power per step when increasing the effort level of skating was larger in the symptomatic group than in the control group for tibialis anterior (143 +/- 12% vs. 125 +/- 23%; Cohen's d = 1.17), peroneus longus (123 +/- 24% vs. 107 +/- 6%; d = 0.91), and gastrocnemius lateralis (167 +/- 51% vs. 117 +/- 12%; d = 1.64). The symptomatic group showed more power in the lower frequency bands of the tibialis anterior's EMG spectra (p < 0.001), whereas no group differences were found in other muscles (all p > 0.2). Within the step cycle, these differences appeared in the swing phase and in the gliding phase during single leg support. The observed differences in the EMG spectra may serve as an early identification of athletes who are at risk of developing CACS.

  8. Effect of kinematic variables on performance in women during a cross-country ski race.

    PubMed

    Rundell, K W; McCarthy, J R

    1996-11-01

    The purpose of this study was to investigate the relationship of uphill cycle velocity, cycle length, and cycle rate in top U.S. female skiers during a multiple lap cross-country ski skating race. Eighteen female cross-country skiers served as subjects at the United States Women's 10-km Freestyle 1995 National Championships. The course consisted of two laps of the same 5-km loop. The selected filming section was an 11-12% uphill grade approximately 400 m long located at the 2.5- and 7.5-km mark. The video sector was approximately 12 m long at the conclusion of the climb. During the climb, the skating technique used by all skiers was the V-1. The results demonstrated that cycle length is positively related to cycle velocity during uphill ski skating and ultimately translates to faster race times by female cross-country ski racers. Lap 2 cycle velocity and cycle length demonstrated the strongest relationship to lap time and total race time. Moreover, cycle rate was not related to cycle velocity or lap race times and was not different between successful and less successful skiers. The slower climbing velocity noted during the latter half of the 10-km race was a consequence of a decreased cycle length and not cycle rate. This suggests that the degree of physical conditioning could be a factor in the ability to maintain cycle length and thus uphill cycle velocity.

  9. Physiological Demands of Competitive Sprint and Distance Performance in Elite Female Cross-Country Skiing.

    PubMed

    Carlsson, Magnus; Carlsson, Tomas; Wedholm, Lars; Nilsson, Mattias; Malm, Christer; Tonkonogi, Michail

    2016-08-01

    Carlsson, M, Carlsson, T, Wedholm, L, Nilsson, M, Malm, C, and Tonkonogi, M. Physiological demands of competitive sprint and distance performance in elite female cross-country skiing. J Strength Cond Res 30(8): 2138-2144, 2016-The purpose was to investigate the relationship between elite females' competitive performance capability in sprint and distance cross-country skiing and the variables of gross efficiency (GE), work rate at the onset of blood-lactate accumulation (OBLA4mmol), maximal oxygen uptake (V[Combining Dot Above]O2max), maximal speed (Vmax), and peak upper-body oxygen uptake (V[Combining Dot Above]O2peak). Ten elite female cross-country skiers (age 24.5 ± 2.8 years) completed treadmill roller-skiing tests to determine GE, OBLA4mmol, and V[Combining Dot Above]O2max using the diagonal-stride technique as well as Vmax and V[Combining Dot Above]O2peak using the double-poling technique. International Ski Federations ranking points for sprint (FISsprint) and distance (FISdist) races were used as competitive performance data. There were correlations between the FISsprint and the V[Combining Dot Above]O2max expressed absolutely (p = 0.0040), Vmax (p = 0.012), and V[Combining Dot Above]O2peak expressed absolutely (p < 0.001) and as a simple ratio-standard (p = 0.049). The FISdist were correlated with OBLA4mmol (p = 0.048), V[Combining Dot Above]O2max expressed absolutely (L·min) (p = 0.015) and as a simple ratio-standard (p = 0.046), and V[Combining Dot Above]O2peak expressed absolutely (p = 0.036) and as a simple ratio-standard (ml·min·kg) (p = 0.040). The results demonstrate that the physiological abilities reflected by V[Combining Dot Above]O2max and V[Combining Dot Above]O2peak are indicators of competitive sprint and distance performance in elite female cross-country skiing. In addition, the ability to generate a high Vmax indicates the performance in sprint races, whereas the skier's OBLA4mmol reflects the performance capability in distance races

  10. Gender differences in wheelchair marathon performance – Oita International Wheelchair Marathon from 1983 to 2011

    PubMed Central

    Lepers, Romuald; Stapley, Paul J; Knechtle, Beat

    2012-01-01

    Background The purpose of the study was (1) to examine the changes in participation and performance of males and females at the Oita International Wheelchair Marathon in Oita, Japan, between 1983 and 2011, and (2) to analyze the gender difference in the age of peak wheelchair marathon performance. Methods Age and time performance data for all wheelchair athletes completing the Oita International Wheelchair Marathon from 1983 to 2011 were analyzed. Results Mean annual number of finishers was 123 ± 43 for males and 6 ± 3 for females (5.0% ± 2.0% of all finishers), respectively. Mean age of overall finishers was significantly (P = 0.026) greater for males (41.3 ± 1.8 years) compared to females (32.7 ± 1.4 years). In contrast, there was no difference in the mean age of the top three overall finishers between males (35.8 ± 3.2 years) and females (31.6 ± 1.5 years). The race time of the top three overall finishers was significantly lower (P < 0.01) for males (1:34 ± 0:11 hours:minutes) compared to females (1:59 ± 0:20 hours:minutes), but it was not significantly different between male (2:06 ± 0:12 hours:minutes) and female (2:12 ± 0:18 hours:minutes) overall finishers. The mean gender difference in time was 26.1% ± 9.7% for the top three overall finishers. Conclusion Further studies are required to investigate the reasons for the low participation of females in wheelchair marathons and why the gender difference in marathon performance is much greater for disabled athletes than for able-bodied athletes. PMID:24198599

  11. Predictor Variables for Marathon Race Time in Recreational Female Runners

    PubMed Central

    Schmid, Wiebke; Knechtle, Beat; Knechtle, Patrizia; Barandun, Ursula; Rüst, Christoph Alexander; Rosemann, Thomas; Lepers, Romuald

    2012-01-01

    Purpose We intended to determine predictor variables of anthropometry and training for marathon race time in recreational female runners in order to predict marathon race time for future novice female runners. Methods Anthropometric characteristics such as body mass, body height, body mass index, circumferences of limbs, thicknesses of skin-folds and body fat as well as training variables such as volume and speed in running training were related to marathon race time using bi- and multi-variate analysis in 29 female runners. Results The marathoners completed the marathon distance within 251 (26) min, running at a speed of 10.2 (1.1) km/h. Body mass (r=0.37), body mass index (r=0.46), the circumferences of thigh (r=0.51) and calf (r=0.41), the skin-fold thicknesses of front thigh (r=0.38) and of medial calf (r=0.40), the sum of eight skin-folds (r=0.44) and body fat percentage (r=0.41) were related to marathon race time. For the variables of training, maximal distance ran per week (r=− 0.38), number of running training sessions per week (r=− 0.46) and the speed of the training sessions (r= − 0.60) were related to marathon race time. In the multi-variate analysis, the circumference of calf (P=0.02) and the speed of the training sessions (P=0.0014) were related to marathon race time. Marathon race time might be partially (r 2=0.50) predicted by the following equation: Race time (min)=184.4 + 5.0 x (circumference calf, cm) –11.9 x (speed in running during training, km/h) for recreational female marathoners. Conclusions Variables of both anthropometry and training were related to marathon race time in recreational female marathoners and cannot be reduced to one single predictor variable. For practical applications, a low circumference of calf and a high running speed in training are associated with a fast marathon race time in recreational female runners. PMID:22942994

  12. Detection of Mycobacterium tuberculosis (MTB) in Fecal Specimens From Adults Diagnosed With Pulmonary Tuberculosis Using the Xpert MTB/Rifampicin Test

    PubMed Central

    Kokuto, Hiroyuki; Sasaki, Yuka; Yoshimatsu, Shoji; Mizuno, Kazue; Yi, Lina; Mitarai, Satoshi

    2015-01-01

    Background. The Xpert Mycobacterium tuberculosis (MTB)/rifampicin (RIF) is a fully automated diagnostic test that allows for the detection of MTB including its RIF resistance. Although the test is used for the diagnosis of tuberculosis (TB) in sputum samples worldwide, studies using fecal specimens are scarce. We therefore evaluated the efficacy of the Xpert MTB/RIF test for detection of MTB in fecal specimens obtained from adult pulmonary TB patients, confirmed by culture and/or molecular diagnostic methods. Methods. We conducted a retrospective case-control study to provide proof-of-concept regarding the efficacy of the Xpert MTB/RIF test using fecal samples for diagnosing pulmonary TB via detection of MTB in adult patients (≥20 years) at the Fukujuji Hospital in Tokyo, Japan. Results. Fecal specimens were obtained from 56 active pulmonary TB patients (including 48 sputum smear-positive and 8 sputum smear-negative patients), 10 non-TB patients (including 4 Myocobacterium avium complex infections), and 27 healthy individuals who were exposed to active pulmonary TB patients. The sensitivity of the fecal Xpert MTB/RIF was 100% (81.7%–100%) for detection of MTB in specimens from sputum smear-positive (1+ to 3+) patients, 81.0% (58.1%–94.6%) in specimens from sputum smear scanty positive patients, and 50.0% (15.7%–84.3%) in specimens from sputum smear-negative patients. Meanwhile, each of the fecal specimens from the non-TB group was negative for MTB (specificity 100%; 95% confidence interval, 86.2–100). Conclusions. The fecal Xpert MTB/RIF test could detect MTB in a large proportion of smear-positive pulmonary TB patients, without frequent false-positive results at a TB referral hospital in Japan. PMID:26125035

  13. MTB-3, a microtubule plus-end tracking protein (+TIP) of Neurospora crassa.

    PubMed

    Mouriño-Pérez, Rosa R; Linacre-Rojas, Lorena P; Román-Gavilanes, Ariana I; Lew, Thomas K; Callejas-Negrete, Olga A; Roberson, Robert W; Freitag, Michael

    2013-01-01

    The microtubule (MT) "plus end" constitutes the platform for the accumulation of a structurally and functionally diverse group of proteins, collectively called "MT plus-end tracking proteins" (+TIPs). +TIPs control MT dynamics and link MTs to diverse sub-cellular structures. Neurospora crassaMicroTubule Binding protein-3 (MTB-3) is the homolog of yeast EB1, a highly conserved +TIP. To address the function of MTB-3, we examined strains with mtb-3 deletions, and we tagged MTB-3 with GFP to assess its dynamic behavior. MTB-3-GFP was present as comet-like structures distributed more or less homogeneously within the hyphal cytoplasm, and moving mainly towards the apex at speeds up to 4× faster than the normal hyphal elongation rates. MTB-3-GFP comets were present in all developmental stages, but were most abundant in mature hyphae. MTB-3-GFP comets were observed moving in anterograde and retrograde direction along the hypha. Retrograde movement was also observed as originating from the apical dome. The integrity of the microtubular cytoskeleton affects the presence and dynamics of MTB-3-GFP comets, while actin does not seem to play a role. The size of MTB-3-GFP comets is affected by the absence of dynactin and conventional kinesin. We detected no obvious morphological phenotypes in Δmtb-3 mutants but there were fewer MTs in Δmtb-3, MTs were less bundled and less organized. Compared to WT, both MT polymerization and depolymerization rates were significantly decreased in Δmtb-3. In summary, the lack of MTB-3 affects overall growth and morphological phenotypes of N. crassa only slightly, but deletion of mtb-3 has strong effect on MT dynamics. PMID:23950979

  14. Lower extremity injuries at the New York City Marathon.

    PubMed

    Caselli, M A; Longobardi, S J

    1997-01-01

    The purpose of this study was to determine the type and frequency of lower extremity running injuries incurred by athletes participating in the New York City Marathon. A survey was conducted of 265 athletes presenting to medical stations for podiatric care during the 1994 New York City Marathon. The results of the survey indicated that the most common injuries occurring in marathon runners were corns, calluses, blisters, muscle cramps, acute knee and ankle injuries, plantar fasciitis, and metatarsalgia. An inverse relationship was observed between the number of miles trained per week and the number of injuries. These findings are consistent with long-term studies of running injuries.

  15. Further examination of the cross-country association between income inequality and population health.

    PubMed

    Ram, Rati

    2006-02-01

    Several scholars have put forward the view that the estimates by Rodgers [(1979). Income and inequality as determinants of mortality: An international cross-section analysis. Population Studies, 33 (2), 343-351], Flegg [(1982). Inequality of income, illiteracy and medical care as determinants of infant mortality in underdeveloped countries. Population Studies, 36 (3), 441-458] and Waldmann [(1992). Income distribution and infant mortality. Quarterly Journal of Economics, 107 (4), 1283-1302] showing a negative cross-country association between income inequality and population health, cannot be replicated from recent data. In view of the importance of this matter, the present study further examines the issue from the most recent, and probably more accurate, data for the largest cross-country sample used in this line of research. The main conclusion is that the negative cross-country association between income inequality and good health, reported by Rodgers, Flegg, and Waldmann, is replicated very well. The different findings indicated by some scholars may have been due to their samples or the models being unusual. Therefore, the recent skepticism about the existence of such a negative association needs to be reconsidered. Several additional points are also noted. First, income inequality shows significance even after an index of ethnic heterogeneity is included. Second, ethnic heterogeneity itself has a negative association with population health. Third, income inequality retains significance in the presence of a measure of social capital. Fourth, however, the association between the measure of social capital and population health appears weak. Fifth, a simple analysis does not support the view that the positive association between income inequality and infant mortality in less developed countries (LDCs) may just be a reflection of the role of poverty. Finally, there is some support for the proposition that while income may be relatively more important for health in

  16. Serum ferritin and serum iron changes after cross-country and roller ski endurance races.

    PubMed

    Pattini, A; Schena, F; Guidi, G C

    1990-01-01

    We have studied the variations induced in iron status parameters by four endurance races of different lengths. A comprehensive group of 48 healthy, non-iron deficient, endurance athletes were evaluated before and after four different cross-country and roller ski races: I = Skirollonga, roller ski race for individuals (n = 10), mean duration (MD) = 1 h 48 min; II = Marcialonga, cross-country ski race for individuals (n = 9) MD = 3 h 10 min; III = 12-h of Caldonazzo (Trento-Italy) roller ski relay race (n = 13) MD = 12 h; IV = 24-h of Pinzolo (Trento-Italy) cross-country ski relay race (n = 16) MD = 24 h. In the relays the MD includes both exercise and recovery times. Blood samples were taken before and after every race for the determination of the following haematological parameters: red blood count, haemoglobin, and packed cell volume, serum iron concentration [SI], serum ferritin concentration [FERR] and total iron binding capacity (TIBC). The results showed a constant significant increase of [FERR] after the races (+44.9% in I, +50.5% in II, +51.2% in III and +36.5% in IV, P less than 0.01) while [SI] increased only in the first two races (+28.2% in I and +19.7% in II, P less than 0.01) and showed a remarkable decrease in the longer races (-46.1% in III and -39% in IV, P less than 0.01). The TIBC increased in all the races (except II) to the same extent (range 10%-12%).(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Effects of training and iron supplementation on iron status of cross-country skiers.

    PubMed

    Pattini, A; Schena, F

    1990-12-01

    We have studied the effects of iron treatment on iron deficient cross-country skiers. Kind and duration of their daily training were also considered. Forty-eight athletes were divided in three balanced groups: Group A received 160 mg ferritinic iron/die, Group B received the same amount of iron and 1 gr of ascorbic acid and Group C was untreated. Blood samples were taken at the start, after two months and four months of supplementation. Hematological and iron status parameters were determined. Average training duration was 80 min a day. Running was the most frequent method of training but also roll and country skiing were commonly used. At the initial sample low serum ferritin values were found in all the three groups (Group A = 23.3 micrograms/l, Group B = 20.9 micrograms/l and Group C = 23.5 micrograms/l). After iron treatment serum ferritin increased in Groups A and B (+67.8% and +63.6% respectively) but was slightly reduced in Group C. Serum iron was unchanged and total iron binding capacity decreased following ferritin increase. Ascorbic acid failed to increase iron absorption in Group B. A significant reduction of haptoglobin (-14% and -9% in Group A and B respectively) was also documented. We conclude that cross-country skiers extensively use running in their training and it may be one of the cause of their poor iron status. Ferritinic iron treatment seems to be effective in replacing iron stores in cross-country skiers who underwent heavy training.

  18. Solar Ultraviolet Radiation Exposure of South African Marathon Runners During Competition Marathon Runs and Training Sessions: A Feasibility Study.

    PubMed

    Nurse, Victoria; Wright, Caradee Y; Allen, Martin; McKenzie, Richard L

    2015-01-01

    Marathon runners spend considerable time in outdoor training for and participating in marathons. Outdoor runners may experience high solar ultraviolet radiation (UVR) exposure. South Africa, where running is popular, experiences high ambient solar UVR levels that may be associated with adverse health effects. This feasibility study explores the use of personal dosimeters to determine solar UVR exposure patterns and possible related acute health risks of four marathon runners during marathons and training sessions in Cape Town and Pretoria. Runners running marathons that started early in the day, and that did not exceed 4 hours, yielded low total solar UVR exposure doses (mean 0.093 SED per exposure period run, median 0.088 SED, range 0.062-0.136 SED; average of 16.54% of ambient solar UVR). Training sessions run during early morning and late afternoon presented similar results. Several challenges hindered analysis including accounting for anatomical position of personal dosimeter and natural shade. To assess health risks, hazard quotients (HQs) were calculated using a hypothetical runner's schedule. Cumulative, annual solar UVR exposure-calculated acute health risks were low (HQ = 0.024) for training sessions and moderate (HQ = 4.922) for marathon runs. While these data and calculations are based on 18 person-days, one can measure marathon runners' personal solar UVR exposure although several challenges must be overcome.

  19. Cross-country disparity in agricultural productivity: quantifying the role of modern seed adoption.

    PubMed

    O'Gorman, Melanie; Pandey, Manish

    2010-01-01

    Inequality of agricultural labour productivity across the developing world has increased substantially over the past 40 years. This article asks: to what extent did the diffusion of Green Revolution seed varieties contribute to increasing agricultural labour productivity disparity across the developing countries? We find that 22 per cent of cross-country variation in agricultural labour productivity can be attributed to the diffusion of high-yielding seed varieties across countries, and that the impact of such diffusion differed significantly across regions. We discuss the implications of these findings for policy directed at increasing agricultural labour productivity in the developing world. PMID:21280414

  20. Spatial query for decision support of cross-country movement. [in image-based geographic information system

    NASA Technical Reports Server (NTRS)

    Hepner, George F.; Logan, Thomas L.; Bryant, Nevin A.

    1988-01-01

    The use of a query language processor for decision support of cross-country movement in an image-based geographic information system is evaluated. It is found that query processing yields results which are comparable to those obtained using conventional cross-country movement techniques and analysis. Query processing also provides a flexibility of information extraction, rapid display, and flexible decision support in time-critical, limited data situations.

  1. The distribution of pace adopted by cyclists during a cross-country mountain bike World Championships.

    PubMed

    Abbiss, Chris R; Ross, Megan L R; Garvican, Laura A; Ross, Neil; Pottgiesser, Torben; Gregory, John; Martin, David T

    2013-01-01

    The purpose of this study was to examine the distribution of pace self-selected by cyclists of varying ability, biological age and sex performing in a mountain bike World Championship event. Data were collected on cyclists performing in the Elite Male (ELITEmale; n = 75), Elite Female (ELITEfemale; n = 50), Under 23 Male (U23male; n = 62), Under 23 Female (U23female; n = 34), Junior Male (JNRmale; n = 71) and Junior Female (JNRfemale; n = 30) categories of the 2009 UCI Cross-Country Mountain Bike World Championships. Split times were recorded for the top, middle and bottom 20% of all finishers of each category. Timing splits were positioned to separate the course into technical and non-technical, uphill, downhill and rolling/flat sections. Compared with bottom performers, top performers in all male categories (ELITEmale, U23male, JNRmale) maintained a more even pace over the event as evidenced by a significantly lower standard deviation and range in average lap speed. Top performers, males, and ELITEmale athletes spent a lower percentage of overall race time on technical uphill sections of the course, compared with middle and bottom placed finishers, females, and JNRmale athletes, respectively. Better male performers adopt a more even distribution of pace throughout cross-country mountain events. Performance of lower placed finishers, females and JNRmale athletes may be improved by enhancing technical uphill cycling ability.

  2. Correlations between physiological variables and performance in high level cross country off road cyclists

    PubMed Central

    Impellizzeri, F; Marcora, S; Rampinini, E; Mognoni, P; Sassi, A

    2005-01-01

    Objectives: To examine the relations between maximal and submaximal indices of aerobic fitness and off road cycling performance in a homogeneous group of high level mountain bikers. Methods: 12 internationally competitive mountain bikers completed the study. Maximum oxygen uptake (V·O2max), peak power output (PPO), power output (PO), and oxygen uptake (V·O2) at first (VT) and second (RCT) ventilatory thresholds were measured in the laboratory, and correlated with race time during a cross country circuit race. Results: The only physiological indices of aerobic fitness correlated with off road cycling performance were PO and V·O2 at RCT when normalised to body mass (r = –0.63 and r = –0.66, respectively; p<0.05). VT, V·O2max, and PPO were not correlated to performance in this homogeneous group of high level mountain bikers. Conclusions: The results of this study suggest that submaximal indices of aerobic fitness such as PO and V·O2 at RCT are more important determinants of off road cycling performance than maximal indices such as PPO and V·O2max. This study confirms the importance of body mass for mountain biking performance. As aerobic fitness explained only 40% of the variance, other physiological and technical factors should be investigated, as they may be important determinants of cross country performance among elite mountain bikers. PMID:16183772

  3. Using the power balance model to simulate cross-country skiing on varying terrain.

    PubMed

    Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell

    2014-01-01

    The current study adapts the power balance model to simulate cross-country skiing on varying terrain. We assumed that the skier's locomotive power at a self-chosen pace is a function of speed, which is impacted by friction, incline, air drag, and mass. An elite male skier's position along the track during ski skating was simulated and compared with his experimental data. As input values in the model, air drag and friction were estimated from the literature based on the skier's mass, snow conditions, and speed. We regard the fit as good, since the difference in racing time between simulations and measurements was 2 seconds of the 815 seconds racing time, with acceptable fit both in uphill and downhill terrain. Using this model, we estimated the influence of changes in various factors such as air drag, friction, and body mass on performance. In conclusion, the power balance model with locomotive power as a function of speed was found to be a valid tool for analyzing performance in cross-country skiing.

  4. The distribution of pace adopted by cyclists during a cross-country mountain bike World Championships.

    PubMed

    Abbiss, Chris R; Ross, Megan L R; Garvican, Laura A; Ross, Neil; Pottgiesser, Torben; Gregory, John; Martin, David T

    2013-01-01

    The purpose of this study was to examine the distribution of pace self-selected by cyclists of varying ability, biological age and sex performing in a mountain bike World Championship event. Data were collected on cyclists performing in the Elite Male (ELITEmale; n = 75), Elite Female (ELITEfemale; n = 50), Under 23 Male (U23male; n = 62), Under 23 Female (U23female; n = 34), Junior Male (JNRmale; n = 71) and Junior Female (JNRfemale; n = 30) categories of the 2009 UCI Cross-Country Mountain Bike World Championships. Split times were recorded for the top, middle and bottom 20% of all finishers of each category. Timing splits were positioned to separate the course into technical and non-technical, uphill, downhill and rolling/flat sections. Compared with bottom performers, top performers in all male categories (ELITEmale, U23male, JNRmale) maintained a more even pace over the event as evidenced by a significantly lower standard deviation and range in average lap speed. Top performers, males, and ELITEmale athletes spent a lower percentage of overall race time on technical uphill sections of the course, compared with middle and bottom placed finishers, females, and JNRmale athletes, respectively. Better male performers adopt a more even distribution of pace throughout cross-country mountain events. Performance of lower placed finishers, females and JNRmale athletes may be improved by enhancing technical uphill cycling ability. PMID:23521618

  5. Upper body heavy strength training does not affect performance in junior female cross-country skiers.

    PubMed

    Skattebo, Ø; Hallén, J; Rønnestad, B R; Losnegard, T

    2016-09-01

    We investigated the effects of adding heavy strength training to a high volume of endurance training on performance and related physiological determinants in junior female cross-country skiers. Sixteen well-trained athletes (17 ± 1 years, 60 ± 6 kg, 169 ± 6 cm, VO2max running: 60 ± 5 mL/kg/min) were assigned either to an intervention group (INT; n = 9) or a control group (CON; n = 7). INT completed two weekly sessions of upper body heavy strength training in a linear periodized fashion for 10 weeks. Both groups continued their normal aerobic endurance and muscular endurance training. One repetition maximum in seated pull-down increased significantly more in INT than in CON, with a group difference of 15 ± 8% (P < 0.01). Performance, expressed as average power output on a double poling ergometer over 20 s and as 3 min with maximal effort in both rested (sprint-test) and fatigued states (finishing-test), showed similar changes in both groups. Submaximal O2 -cost and VO2peak in double poling showed similar changes or were unchanged in both groups. In conclusion, 10 weeks of heavy strength training increased upper body strength but had trivial effects on performance in a double poling ergometer in junior female cross-country skiers.

  6. Biomechanical analysis of the herringbone technique as employed by elite cross-country skiers.

    PubMed

    Andersson, E; Stöggl, T; Pellegrini, B; Sandbakk, O; Ettema, G; Holmberg, H-C

    2014-06-01

    This investigation was designed to analyse the kinematics and kinetics of cross-country skiing at different velocities with the herringbone technique on a steep incline. Eleven elite male cross-country skiers performed this technique at maximal, high, and moderate velocities on a snow-covered 15° incline. They positioned their skis laterally (25 to 30°) with a slight inside tilt and planted their poles laterally (8 to 12°) with most leg thrust force exerted on the inside forefoot. Although 77% of the total propulsive force was generated by the legs, the ratio between propulsive and total force was approximately fourfold higher for the poles. The cycle rate increased with velocity (1.20 to 1.60 Hz), whereas the cycle length increased from moderate up to high velocity, but then remained the same at maximal velocity (2.0 to 2.3 m). In conclusion, with the herringbone technique, the skis were angled laterally without gliding, with the forces distributed mainly on the inside forefoot to enable grip for propulsion. The skiers utilized high cycle rates with major propulsion by the legs, highlighting the importance of high peak and rapid generation of leg forces.

  7. Endurance training and the risk of bronchial asthma in female cross-country skiers.

    PubMed

    Żebrowska, A; Głuchowska, B; Jastrzębski, D; Kochańska-Dziurowicz, A; Stanjek-Cichoracka, A; Pokora, I

    2015-01-01

    Exercise is one of the crucial factors responsible for asthma development and exacerbation. The purpose of the present study was to assess the risk of bronchial asthma in female athletes. Spirometric evaluations and physical exercise test were performed and exhaled nitric oxide (eNO) levels were measured in 12 female elite cross-country skiers. Serum concentrations of interleukin 1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6) were measured in all subjects before exercise, immediately after it, and after 15 min of recovery. Peak eNO values were 18.7±4.8 (ppb) and did not confirm the risk of early bronchial asthma symptoms. A graded exercise test caused significant increases in TNF-α and IL-1β concentration (p<0.05) after 15 min of recovery. A significant negative correlation was found between resting and post-exercise eNO and IL-6 levels (p<0.01). Our study did not confirm an increased risk of bronchial asthma or respiratory tract inflammatory conditions among female cross-country skiers exposed to physical exertion.

  8. Downhill turn techniques and associated physical characteristics in cross-country skiers.

    PubMed

    Sandbakk, S Bucher; Supej, M; Sandbakk, Ø; Holmberg, H-C

    2014-08-01

    Three dominant techniques are used for downhill turning in cross-country skiing. In this study, kinematic, kinetic, and temporal characteristics of these techniques are described and related to skier strength and power. Twelve elite female cross-country skiers performed six consecutive turns of standardized geometry while being monitored by a Global Navigation Satellite System. Overall time was used as an indicator of performance. Skiing and turning parameters were determined from skier trajectories; the proportional use of each technique was determined from video analysis. Leg strength and power were determined by isometric squats and countermovement jumps on a force plate. Snow plowing, parallel skidding, and step turning were utilized for all turns. Faster skiers employed less snow plowing and more step turning, more rapid deceleration and earlier initiation of step turning at higher speed (r = 0.80-0.93; all P < 0.01). Better performance was significantly correlated to higher mean speed and shorter trajectory (r = 0.99/0.65; both P < 0.05) and to countermovement jump characteristics of peak force, time to peak force, and rate of force development (r = -0.71/0.78/-0.83; all P < 0.05). In conclusion, faster skiers used step turning to a greater extent and exhibited higher maximal leg power, which enabled them to combine high speeds with shorter trajectories during turns.

  9. Endurance training and sprint performance in elite junior cross-country skiers.

    PubMed

    Sandbakk, Øyvind; Welde, Boye; Holmberg, Hans-Christer

    2011-05-01

    The purpose of the present study was to investigate the relationship between aerobic characteristics and sprint skiing performance, and the effects of high-intensity endurance training on sprint skiing performance and aerobic characteristics. Ten male and 5 female elite junior cross-country skiers performed an 8-week intervention training period. The intervention group (IG, n = 7) increased the volume of high-intensity endurance training performed in level terrain, whereas the control group (CG, n = 8) continued their baseline training. Before and after the intervention period, the skiers were tested for 1.5-km time-trial performance on roller skis outdoors in the skating technique. Maximal oxygen uptake (VO₂max) and oxygen uptake at the ventilatory threshold (VO₂VT) were measured during treadmill running. VO₂max and VO₂VT were closely related to sprint performance (r = ~0.75, both p < 0.008). The IG improved sprint performance, VO₂max, and VO₂VT from pre to posttesting and improved sprint performance and VO₂VT when compared to the CG (all p < 0.01). This study shows a close relationship between aerobic power and sprint performance in cross-country skiing and highlights the positive effects of high-intensity endurance training in level terrain.

  10. Effect of drafting on heart rate in cross-country skiing.

    PubMed

    Bilodeau, B; Roy, B; Boulay, M R

    1994-05-01

    The purpose of this study was to compare the heart rate responses during cross-country skiing as a leading skier, as well as in a drafting situation, 2 m behind the leader. Six male cross-country ski racers, paired for VO2max skied a 2-km course (two loops of 1 km) using the skating techniques at a fixed speed (5.6 m.s-1) on two different occasions, once as a leading skier, the other as a drafter. A recovery period of 30 min was allowed between the two trials. Heart rates (HR) were monitored every 5 s during all performances. Capillary blood lactate concentrations were taken before and at 5 min posttrial. Results revealed that HR were significantly lower (154 vs 163 beats.min-1) when skiing behind another skier as opposed to leading. Lactate concentrations were not significantly different between the two trials. Results also revealed that projected frontal areas appeared to influence the effects of drafting such that the HR differences between the leading and the drafting situations were larger for smaller skiers drafting behind larger skiers. These results showed that skiing behind another skier in a ski race would be very advantageous when the situation is encountered and that coaches should use the drafting situation in training so that athletes can practice this energy-saving strategy.

  11. 9. View of bridge looking west. A fundraising marathon is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. View of bridge looking west. A fund-raising marathon is in prgress. The traffic levels outside the main arch were added in 1965 when the bridge underwent extensive rehabilitation. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

  12. Marathon Training in the University Physical Education Curriculum.

    ERIC Educational Resources Information Center

    Dernbach, Arthur R.

    1983-01-01

    A course at Northern Illinois University trains college students for running marathons. The course offers information about conditioning, injury prevention, and diet requirements, as well as instruction in long-distance running. Techniques for motivating students are discussed. (PP)

  13. Sudden cardiac death in marathons: a systematic review.

    PubMed

    Waite, Oliver; Smith, Andy; Madge, Luke; Spring, Hannah; Noret, Nathalie

    2016-01-01

    The aim of this systematic review is to summarise the results of cohort studies that examined the incidence of SCD in marathons and to assess the quality of the methods used. A search of the PROSPERO international database revealed no prospective or published systematic reviews investigating SCD in marathons. The review was conducted using studies that reported and characterised the incidence of SCD in people participating in marathons. Studies were identified via electronic database searches (Medline, CINAHL, SPORTDiscus and Google Scholar) from January 1, 1966 to October 1, 2014 and through manual literature searches. 7 studies met the inclusion criteria and were included in this review. 6 of the studies were conducted in the USA and 1 in the UK. These studies covered a 34-year period involving between 215,413 and 3,949,000 runners. The SCD of between 4 and 28 people are recorded in the papers and the reported estimates of the incidence of SCD in marathons ranged widely from 0.6 to 1.9 per 100,000 runners. The proportion of those suffering SCD who were male ranged from 57.1% to 100% and the mean age reported in the papers, ranged from 37 to 48. This review raises 4 methodological concerns over i) collating reports of SCD in marathons; ii) time of death in relation to the marathon; iii) the use of registrants rather than runners in the estimates of sample size and iv) limited detail on runners exercise history. These four concerns all threaten the reliability and interpretation of any estimate of SCD incidence rates in marathons.  This review recommends that the methods used to collect data on SCD in marathons be improved and that a central reporting system be established. PMID:26765272

  14. Beating the storm. [Procedures of Marathon Oil Co

    SciTech Connect

    Stelzer, D.A.

    1983-01-01

    In this article, Mr. Stelzer describes the activities of management and crews when weather advisories dictate emergency shutdown of Marathon's western Gulf of Mexico drilling activities. The Lafayette, LA office monitors the atmospheric disturbances (seeds of potential hurricanes) and, eventually, the growing storm, and alerts all Marathon platforms in Sector 2 of the western Gulf to prepare for possible shutdown. In the example described here, management gave the order at 7:00 AM to shut down all Marathon platforms and shore bases in the vicinity of the western Gulf as Hurricane Alicia built up eastward. Within minutes, a well-practed series of exercises was put in motion - lowering and chaining down lengths of drill pipe, securing anything else that could be chained down, and starting the orderly evacuation of the platform workers (by helicopter, when possible). By 5:35 PM, just 10.5 hours after the alert, all personnel from the 13 Marathon platforms had been safely transported to Lafayette and Lake Charles, LA. The shore bases themselves were then secured and vacated to await the storm's fury. Alicia eventually slammed ashore, wreaking extensive storm damage in Galveston, Houston, and Texas City; a Marathon refinery in the latter sustained heavy property loss and interruption of work. Offshore, there was very little damage aboard the Marathon platforms; and, within hours, all platforms were back in operation.

  15. The SPLASH/ICPC integrity marathon in Ibadan, Nigeria: incidence and management of injuries and marathon-related health problems

    PubMed Central

    2013-01-01

    Background The growing interest in marathon runners and marathons in Nigeria has not been reflected in reports of injuries and other health problems associated with these events. This study therefore outlines the incidence of injuries, marathon-related health problems and delivery of physiotherapy at the maiden and second editions of the Splash 105.5 FM/ICPC Integrity Marathon in Ibadan city, south-west Nigeria in 2009 and 2010. Methods Using a data entry sheet, demographics and information on running experience, past and present injuries and other health problems reported en route and at the finish line by the runners were documented. The prevalence of injuries and other health problems reported by previous and first-time runners were compared. Results In both events, 16.3% and 17.2% of the runners respectively reported injuries with significant occurrence in first-time runners (p = 0.003 for 2009; p = 0.002 for 2010) mostly at the finish line. The reported injury type and site were muscle cramps and the thigh (39.7% and 76.4% respectively). Heat exhaustion was reported by 42.8% of runners in 2009 and 56.3% in 2010. Cryotherapy was mostly used in combination with other physiotherapy modalities in both years. Conclusion Most of the injuries and other health problems were reported by first-time marathon runners mainly at the finish line. The most reported site of injury was the thigh while muscle cramps and heat exhaustions were the most reported types of injuries and health problems. First-time marathon runners should be adequately informed of the predisposition to injury during marathons and adequate body conditioning should be emphasized. Ample preparation and effective involvement of the physiotherapy team is essential for management of injured runners en route and at the finish line in a marathon. PMID:24499546

  16. [Physiological effects of ultra-marathon run].

    PubMed

    Akimov, E B; Son'kin, V D

    2012-01-01

    We investigated the performance of vegetative systems of the body, and gas exchange in the implementation of one athlete (master of skiing, 27 years, MaxVO2 = 67 ml/min/kg) during 6 hours ultra-marathon race in a closed stadium at an average speed of 2.7 m/s. Continuous monitoring of heart rate was carried out using the heart rate monitor Polar RS 800. During the first hour and then for 20-30 minutes each hour gas analysis was performed with Metamaxdevice (Germany), mounted on the test subject during all the time of the race. Before and after the passages of the measured interval distance blood lactate content was measured. These data demonstrate a number of features that accompany fatigue in the final stretches a distance: reduction of body economy, which is to increase heart rate and oxygen cost of work; activation of anaerobic-glycolitic energy production mechanism, the intensification of respiratory function. Along with this, the methods of correlation and regression analysis revealed changes (increase or decrease) the relationship between the functions depending on whether the body is in the initial stage of the physical load, sustainable high performance or in either a state of extreme fatigue. These results suggest the interference effects of the central and tissue mechanisms of fatigue in the organization of the oxygen transport function of the body. Apparently, in the case of ultra-marathon run, that is, long-term work of moderate power, the main limiting factor is not the energy of the body, and the autonomic software. PMID:23393784

  17. A Comparison of Frontal Theta Activity During Shooting among Biathletes and Cross-Country Skiers before and after Vigorous Exercise

    PubMed Central

    Luchsinger, Harri; Sandbakk, Øyvind; Schubert, Michael; Ettema, Gertjan; Baumeister, Jochen

    2016-01-01

    Background Previous studies using electroencephalography (EEG) to monitor brain activity have linked higher frontal theta activity to more focused attention and superior performance in goal-directed precision tasks. In biathlon, shooting performance requires focused attention after high-intensity cross-country skiing. Purpose To compare biathletes (serving as experts) and cross-country skiers (novices) and examine the effect of vigorous exercise on frontal theta activity during shooting. Methods EEG frontal theta (4–7 Hz) activity was compared between nine biathletes and eight cross-country skiers at comparable skiing performance levels who fired 100 shots on a 5-m indoor shooting range in quiescent condition followed by 20 shots after each of five 6-min high-intensity roller skiing sessions in the skating technique on a treadmill. Results Biathletes hit 80±14% and 81±10% before and after the roller skiing sessions, respectively. For the cross-country skiers these values were significantly lower than for the biathletes and amounted to 39±13% and 44±11% (p<0.01). Biathletes had on average 6% higher frontal theta activity during shooting as compared to cross-country skiers (F1,15 = 4.82, p = 0.044), but no significant effect of vigorous exercise on frontal theta activity in either of the two groups were found (F1,15 = 0.14, p = 0.72). Conclusions Biathletes had significantly higher frontal theta activity than cross-country skiers during shooting, indicating higher focused attention in biathletes. Vigorous exercise did not decrease shooting performance or frontal theta activity during shooting in biathletes and cross-country skiers. PMID:26981639

  18. Corruption costs lives: a cross-country study using an IV approach.

    PubMed

    Lio, Mon-Chi; Lee, Ming-Hsuan

    2016-04-01

    This study quantitatively estimates the effects of corruption on five major health indicators by using recent cross-country panel data covering 119 countries for the period of 2005-2011. The corruption indicators provided by the World Bank and Transparency International are used, and both the two-way fixed effect and the two-stage least squares approaches are employed for our estimation. The estimation results show that, in general, corruption is negatively associated with a country's health outcomes. A lower level of corruption or a better control of corruption in a country can lead to longer life expectancy, a lower infant mortality rate and a lower under-five mortality rate for citizens. However, our estimation finds no significant association between corruption and individual diseases including human immunodeficiency virus prevalence and tuberculosis incidence. The findings suggest that corruption reduction itself is an effective method to promote health. Copyright © 2015 John Wiley & Sons, Ltd.

  19. Effects of carbohydrate dose and frequency on metabolism, gastrointestinal discomfort, and cross-country skiing performance.

    PubMed

    Stocks, B; Betts, J A; McGawley, K

    2016-09-01

    This study investigated carbohydrate ingestion of varied doses and frequencies during a simulated cross-country skiing time trial. Ten men and three women (age: 30 ± 7 years; V ˙ O 2 m a x : 59.6 ± 5.7 mL/kg/min) completed four, 30-km classic technique roller skiing time trials on a treadmill. A 1:1 maltodextrin-fructose carbohydrate solution was provided at high (2.4 g/min; HC) and moderate (1.2 g/min; MC) ingestion rates, each at high (six feeds; HF) and low (two feeds; LF) frequencies. In the LF trials, blood glucose was elevated following carbohydrate ingestion (at 4 and 19 km) but was reduced at 14 and 29 km compared with HF strategies (P ≤ 0.05). Gastrointestinal discomfort was higher in HC-LF compared with all other trials (P ≤ 0.05). Whole-body lipid oxidation was lower and carbohydrate oxidation was higher in LF compared with HF trials (P ≤ 0.05). While performance time was not significantly different between trials (140:11 ± 15:31, 140:43 ± 17:40, 139:12 ± 15:32 and 140:33 ± 17:46 min:s in HC-HF, HC-LF, MC-HF, and MC-LF, respectively; P > 0.05), it was improved with trial order (P < 0.001). There was no effect of order on any other variable (P > 0.05). Altering carbohydrate dose or frequency does not affect cross-country ski performance. However, low-frequency carbohydrate ingestion resulted in poorer maintenance of euglycemia, reduced lipid oxidation, and increased gastrointestinal discomfort.

  20. Kinematics of cross-country sit skiing during a Paralympic race.

    PubMed

    Bernardi, Marco; Janssen, Thomas; Bortolan, Lorenzo; Pellegrini, Barbara; Fischer, Gabriela; Schena, Federico

    2013-02-01

    The study had three purposes: to verify a hypothesized speed decrease during the 15 km cross-country sit skiing (CCSS) race; documenting this possible fatigue effect (speed decrease), to evaluate changes among the four laps in kinematics parameters (cycle speed, cycle duration, cycle length, duty cycle (percentage ratio between pushing and total cycle duration), pole inclination, trunk inclination and shoulder-hand distance); to compare the kinematics parameters in cross-country sit skiers of different level. Video recordings were carried out during the 2006 Turin Winter Paralympic Games with two conventional digital video-cameras positioned on a flat and an uphill (8.3°) track, respectively. Better performing skiers (G1) had significantly higher speeds than worse performers (G2) both in the flat (6.54 ± 0.13 vs. 5.89 ± 0.50 ms(-1) and 5.55 ± 0.14 vs. 4.62 ± 0.22 ms(-1) in the first and last lap, respectively) and in the uphill track (3.67 ± 0.45 vs. 3.05 ± 0.59 ms(-1) and 3.20 ± 0.36 vs. 2.26 ± 0.36 ms(-1) in the first and last lap, respectively). The G1 athletes were able to maintain the high-speed better than the G2 over the entire race. Significant differences in cycle length and duty cycle between groups would be justified by the higher physical fitness of G1 skiers.

  1. Effect of ambient temperature on endurance performance while wearing cross-country skiing clothing.

    PubMed

    Sandsund, Mariann; Saursaunet, Vegard; Wiggen, Øystein; Renberg, Julie; Færevik, Hilde; van Beekvelt, Mireille C P

    2012-12-01

    This study assessed the effects of exposure to cold (-14 and -9 °C), cool (-4 and 1 °C) and moderate warm (10 and 20 °C) environments on aerobic endurance performance-related variables: maximal oxygen consumption (VO(2max)), running time to exhaustion (TTE), running economy and running speed at lactate threshold (LT). Nine male endurance athletes wearing cross-country ski racing suit performed a standard running test at six ambient temperatures in a climatic chamber with a wind speed of 5 m s(-1). The exercise protocol consisted of a 10-min warm-up period followed by four submaximal periods of 5 min at increasing intensities between 67 and 91 % of VO(2max) and finally a maximal test to exhaustion. During the time course mean skin temperature decreased significantly with reduced ambient temperatures whereas T (re) increased during all conditions. T (re) was lower at -14 °C than at -9 and 20 °C. Running economy was significantly reduced in warm compared to cool environments and was also reduced at 20 °C compared to -9 °C. Running speed at LT was significantly higher at -4 °C than at -9, 10 and 20 °C. TTE was significantly longer at -4 and 1 °C than at -14, 10 and 20 °C. No significant differences in VO(2max) were found between the various ambient conditions. The optimal aerobic endurance performance wearing a cross-country ski racing suit was found to be -4 and 1 °C, while performance was reduced under moderate warm (10 and 20 °C) and cold (-14 and -9 °C) ambient conditions.

  2. Changes in technique and efficiency after high-intensity exercise in cross-country skiers.

    PubMed

    Åsan Grasaas, Christina; Ettema, Gertjan; Hegge, Ann Magdalen; Skovereng, Knut; Sandbakk, Øyvind

    2014-01-01

    This study investigated changes in technique and efficiency after high-intensity exercise to exhaustion in elite cross-country skiers. Twelve elite male skiers completed 4 min submaximal exercise before and after a high-intensity incremental test to exhaustion with the G3 skating technique on a 5% inclined roller-ski treadmill. Kinematics and kinetics were monitored by instrumented roller skis, work rate was calculated as power against roller friction and gravity, aerobic metabolic cost was determined from gas exchange, and blood lactate values indicated the anaerobic contribution. Gross efficiency was the work rate divided by aerobic metabolic rate. A recovery period of 10 min between the incremental test and the posttest was included to allow the metabolic values to return to baseline. Changes in neuromuscular fatigue in upper and lower limbs before and after the incremental test were indicated by peak power in concentric bench press and squat-jump height. From pretest to posttest, cycle length decreased and cycle rate increased by approximately 5% (P < 0.001), whereas the amount of ski forces did not change significantly. Oxygen uptake increased by 4%, and gross efficiency decreased from 15.5% ± 0.7% to 15.2% ± 0.5% from pretest to posttest (both P < .02). Correspondingly, blood lactate concentration increased from 2.4 ± 1.0 to 6.2 ± 2.5 mmol/L (P < .001). Bench-press and squat-jump performance remained unaltered. Elite cross-country skiers demonstrated a less efficient technique and shorter cycle length during submaximal roller-ski skating after high-intensity exercise. However, there were no changes in ski forces or peak power in the upper and lower limbs that could explain these differences.

  3. Gender differences in the physiological responses and kinematic behaviour of elite sprint cross-country skiers.

    PubMed

    Sandbakk, Oyvind; Ettema, Gertjan; Leirdal, Stig; Holmberg, Hans-Christer

    2012-03-01

    Gender differences in performance by elite endurance athletes, including runners, track cyclists and speed skaters, have been shown to be approximately 12%. The present study was designed to examine gender differences in physiological responses and kinematics associated with sprint cross-country skiing. Eight male and eight female elite sprint cross-country skiers, matched for performance, carried out a submaximal test, a test of maximal aerobic capacity (VO(2max)) and a shorter test of maximal treadmill speed (V (max)) during treadmill roller skiing utilizing the G3 skating technique. The men attained 17% higher speeds during both the VO(2max) and the V (max) tests (P < 0.05 in both cases), differences that were reduced to 9% upon normalization for fat-free body mass. Furthermore, the men exhibited 14 and 7% higher VO(2max) relative to total and fat-free body mass, respectively (P < 0.05 in both cases). The gross efficiency was similar for both gender groups. At the same absolute speed, men employed 11% longer cycles at lower rates, and at peak speed, 21% longer cycle lengths (P < 0.05 in all cases). The current study documents approximately 5% larger gender differences in performance and VO(2max) than those reported for comparable endurance sports. These differences reflect primarily the higher VO(2max) and lower percentage of body fat in men, since no gender differences in the ability to convert metabolic rate into work rate and speed were observed. With regards to kinematics, the gender difference in performance was explained by cycle length, not by cycle rate.

  4. Motility of magnetotactic bacteria/MTB to Geomagnetic fields

    NASA Astrophysics Data System (ADS)

    Hidajatullah-Maksoed, Fatahillah

    2016-03-01

    Bacteria with motility directed by a local geomagnetic fields have been observed in marine sediments'' discussed by R. Blakemore, 1975. Magnetotactic bacteria/MTB discovered in 1963 by Salvatore Bellini. For ``off-axis electron holography in the transmission electron microscope was used to correlates the physical & magnetic microstructure of magnetite nanocrystals in magnetotactic bacteria'' sought ``single-domain magnetite in hemopelagic sediments'' from JF Stolz. Otherwise, for potential source of bioproducts- product meant from result to multiplier -of magnetotactic bacteria[ACV Araujo, et.al, 2014 ] of marine drugs retrieved the `measurement of cellular chemotaxis with ECIS/Taxis, from KM Pietrosimone, 2012, whereas after ``earth magnetic field role on small living models'' are other interpretation of ``taxis'' as a movement of a cell instead usual ``tax'' for yew's taxus cuspidate, hired car & taxes in financial realms. Acknowledgements to HE. Mr. H. TUK SETYOHADI, Jl. Sriwijaya Raya 3, South-Jakarta, INDONESIA.

  5. Molecular characterization of Mtb-OMP decarboxylase by modeling, docking and dynamic studies.

    PubMed

    Madhusudana, P; Babajan, B; Chaitanya, M; Anuradha, C M; Shobharani, C; Chikati, Rajasekar; Kumar, Chitta Suresh; Rao, K R S Sambasiva; Poda, Sudhakar

    2012-06-01

    Tuberculosis (TB), the second most deadly disease in the world is caused by Mycobacterium tuberculosis (Mtb). In the present work a unique enzyme of Mtb orotidine 5' monophosphate decarboxylase (Mtb-OMP Decase) is selected as drug target due to its indispensible role in biosynthesis of pyrimidines. The present work is focused on understanding the structural and functional aspects of Mtb-OMP Decase at molecular level. Due to absence of crystal structure, the 3D structure of Mtb-OMP Decase was predicted by MODELLER9V7 using a known structural template 3L52. Energy minimization and refinement of the developed 3D model was carried out with Gromacs 3.2.1 and the optimized homology model was validated by PROCHECK,WHAT-IF and PROSA2003. Further, the surface active site amino acids were quantified by WHAT-IF pocket. The exact binding interactions of the ligands, 6-idiouridine 5' monophosphate and its designed analogues with the receptor Mtb-OMP Decase were predicted by docking analysis with AUTODOCK 4.0. This would be helpful in understanding the blockade mechanism of OMP Decase and provide a candidate lead for the discovery of Mtb-OMP Decase inhibitors, which may bring insights into outcome new therapy to treat drug resistant Mtb.

  6. Improved Race Times in Marathoners Older than 75 Years in the Last 25 Years in the World's Largest Marathons.

    PubMed

    Ahmadyar, Baschir; Rosemann, Thomas; Rüst, Christoph Alexander; Knechtle, Beat

    2016-06-30

    Performance trends of elite marathoners are well investigated. However, performance of elderly marathoners (> 75 years) competing in the world's largest city marathons is not well-known. We examined marathon race data of 1,691 marathon finishes (i.e. 218 women and 1,473 men) competing between 1990 and 2014 in 5-year age groups 75-79, 80-84, 85-89, and 95-99 years in four races (Berlin, New York, Chicago and Boston) of the 'World Marathon Majors'. The number of female (r² = 0.50, P < 0.0001) and male (r² = 0.88, P < 0.0001) finishers increased significantly across years. The number of women (r² = 0.36, P = 0.0019) and men (r² = 0.88, P < 0.0001) in age group 75-79 years increased. In age group 80-84 years, the number of women (r² = 0.36, P = 0.0111) and men (r² = 0.54, P < 0.0001) also increased. In age groups 85-89 to 95-99 years, however, the number of female and male finishers remained unchanged. Across years, women (r² = 0.26, P = 0.0090) and men (r² = 0.31, P = 0.0035) reduced their race times. Women and men in age group 75-79 years improved race times. In age groups 80-84 to 90-94 years, women and men were not able to reduce race times. In summary, participation increased and performance improved in female and male marathoners competing in age groups 75-79 to 95-99 years where the largest increases in participation and the largest improvements in performance were found in women and men in age group 75-79 years. PMID:27188466

  7. Evaluation of Cobas TaqMan MTB PCR for detection of Mycobacterium tuberculosis.

    PubMed

    Kim, Jeong Hyun; Kim, Young Jae; Ki, Chang-Seok; Kim, Ji-Youn; Lee, Nam Yong

    2011-01-01

    Nucleic acid-based amplification tests allow the rapid detection of Mycobacterium tuberculosis. Recently, a real-time PCR assay for M. tuberculosis complex, the Cobas TaqMan MTB test (Roche Diagnostics, Basel, Switzerland), was introduced. We performed a prospective study to evaluate the diagnostic performance of the Cobas TaqMan MTB test system. A total of 406 specimens collected from 247 patients were simultaneously tested by conventional culture, Cobas Amplicor MTB PCR, and TaqMan MTB PCR. The cross-reactivity with other Mycobacterium species and the detection limit were also evaluated. Among 406 specimens, a total of 24 specimens (5.9%) were culture positive: 14 specimens were positive by both TaqMan and Amplicor MTB PCRs, while 5 specimens were positive by only TaqMan PCR. The remaining five specimens were negative by both PCR methods. Seven specimens with negative culture results were positive by TaqMan PCR, but five of these were negative by Amplicor MTB PCR. The sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were 79.1%, 98.2%, 73.1%, and 98.7% for TaqMan and 58.3%, 99.5%, 87.5%, and 97.4% for the Amplicor MTB PCR test, respectively. There was no cross-reactivity with M. tuberculosis and nontuberculous mycobacterial species. The detection limit for the Cobas TaqMan MTB PCR test was 4.0 copies/μl. The Cobas TaqMan MTB PCR test showed higher sensitivity for detection of the M. tuberculosis complex without disturbing the specificity and NPV than the Amplicor MTB PCR test.

  8. Public spending for illegal drug and alcohol treatment in hospitals: an EU cross-country comparison

    PubMed Central

    2014-01-01

    Background In view of the current economic crisis and the resulting austerity measures being implemented by governments across Europe, public expenditure for substance abuse treatment has increasingly become a subject of discussion. An EU cross-country comparison would allow an estimation of the total amount of public resources spent on substance abuse treatment, compare various substance abuse treatment funding options, and evaluate the division of expenditures between alcohol and illegal drugs. The purpose of this study is to estimate the public spending of EU countries for alcohol and illegal drug abuse treatment in hospitals. Methods Our study uses a uniform methodology in order to enable valid cross-national comparisons. Our data are drawn from the Eurostat database, which provides anno 2010 data on government spending for the treatment of illegal drug and alcohol abuse in 21 EU member states. The cross-country comparison is restricted to hospitals, since data were unavailable for other types of treatment providers. The systematic registration of in- and outpatient data is essential to monitoring public expenditures on substance abuse treatment using international databases. Results Total public spending for hospital-based treatment of illegal drug and alcohol abuse in the 21 EU member states studied is estimated to be 7.6 billion euros. Per capita expenditures for treatment of illegal drug abuse vary, ranging from 0.1 euros in Romania to 13 euros in Sweden. For alcohol abuse, that figure varied from 0.9 euros in Bulgaria to 24 euros in Austria. These results confirm other studies indicating that public expenditures for alcohol treatment exceed that for illegal drug treatment. Conclusions Multiple factors may influence the number of hospital days for alcohol or illegal substance abuse treatment, and expenditures fluctuate accordingly. In this respect, we found a strong correlation between gross domestic product (GDP) per capita and public expenditures per

  9. Reduced performance difference between sexes in master mountain and city marathon running

    PubMed Central

    Zingg, Matthias A; Knechtle, Beat; Rüst, Christoph Alexander; Rosemann, Thomas; Lepers, Romuald

    2013-01-01

    Background The performance in master marathoners has been investigated in flat city marathons but not in mountain marathons. This study examined changes in the sex differences in performance across time in female and male master runners competing in a mountain marathon compared to a flat city marathon. Methods The association between age and performance of finishers in the Jungfrau Marathon, Switzerland, with 1830 meter changes in altitude and a flat city marathon (Lausanne Marathon), Switzerland, were analyzed from 2000 to 2011. Results In both events, athletes in the 35–44 years age group showed the highest number of finishers. In the mountain marathon, the number of female master runners aged > 35 years increased in contrast to female finishers aged < 35 years, while the number of male finishers was unchanged in all age groups. In the city marathon, the number of female finishers was unchanged while the number of male finishers in the age groups for 25–34-year-olds and 35–44-year-olds decreased. In female marathoners, performance improved in athletes aged 35–44 and 55–64 years in the city marathon. Male marathoners improved race time in age group 45–54 years in both the city marathon and the mountain marathon. Female master runners reduced the sex difference in performance in the 45–54-year age group in both competitions and in the 35–44-year age group in the mountain marathon. The sex difference in performance decreased in the 35–44-year age group from 19.1% ± 4.7% to 16.6% ± 1.9% in the mountain marathon (r2 = 0.39, P = 0.03). In age groups 45–54 years, the sex difference decreased from 23.4% ± 1.9% to 15.9% ± 6.1% in the mountain marathon (r2 = 0.39, P < 0.01) and from 34.7% ± 4.6% to 11.8% ± 6.2% in the city marathon (r2 = 0.39, P < 0.01). Conclusion These findings suggest that female master runners aged 35–54 years reduced sex differences in their performance in both mountain and city marathon running. PMID:23637550

  10. In-season dietary adequacy of trained male cross-country runners.

    PubMed

    Niekamp, R A; Baer, J T

    1995-03-01

    The purpose of this study was to determine the dietary adequacy of 12 collegiate cross-country runners during a competitive season. Four-day diet records were collected twice during the season and analyzed for total daily energy, macronutrients, vitamin A, vitamin C, thiamin, riboflavin, niacin, vitamin B6, folate, iron, magnesium, zinc, and calcium. Mean energy intake (3,248 +/- 590 kcal) was not significantly different from estimated mean energy expenditure (3,439 +/- 244 kcal). Week 8 mean prealbumin levels were within normal limits (26.8 +/- 2.8 mg/dl). Mean daily CHO intake was 497 +/- 134 g/day (61.2%). Three to four hours prior to competition a pre-race meal was consumed; it contained 82 +/- 47 g CHO. Postcompetition CHO intake was delayed an average 2.5 hr; at that time approximately 2.6 +/- 0.69 g CHO/kg body weight was consumed. The athletes appeared to demonstrate dietary adequacy with the exception of timing of postcompetition carbohydrate consumption.

  11. Comparison of manually produced and automated cross country movement maps using digital image processing techniques

    NASA Technical Reports Server (NTRS)

    Wynn, L. K.

    1985-01-01

    The Image-Based Information System (IBIS) was used to automate the cross country movement (CCM) mapping model developed by the Defense Mapping Agency (DMA). Existing terrain factor overlays and a CCM map, produced by DMA for the Fort Lewis, Washington area, were digitized and reformatted into geometrically registered images. Terrain factor data from Slope, Soils, and Vegetation overlays were entered into IBIS, and were then combined utilizing IBIS-programmed equations to implement the DMA CCM model. The resulting IBIS-generated CCM map was then compared with the digitized manually produced map to test similarity. The numbers of pixels comprising each CCM region were compared between the two map images, and percent agreement between each two regional counts was computed. The mean percent agreement equalled 86.21%, with an areally weighted standard deviation of 11.11%. Calculation of Pearson's correlation coefficient yielded +9.997. In some cases, the IBIS-calculated map code differed from the DMA codes: analysis revealed that IBIS had calculated the codes correctly. These highly positive results demonstrate the power and accuracy of IBIS in automating models which synthesize a variety of thematic geographic data.

  12. Reliability and validity of a new double poling ergometer for cross-country skiers.

    PubMed

    Holmberg, Hans-Christer; Nilsson, Johnny

    2008-01-15

    Thirty-eight competitive cross-country skiers were divided into three groups to assess the reliability and validity of a new double poling ergometer. Group A (n = 22) performed two maximal 60-s tests, Group B (n = 8) repeated peak oxygen uptake tests on the double poling ergometer, and Group C (n = 8) performed a maximal 6-min test on the double poling ergometer and a double poling time-trial on snow. The correlation between the power calculated at the flywheel and the power applied at the base of the poles was r = 0.99 (P < 0.05). The power at the poles was 50-70% higher than that at the flywheel. There was a high test-retest reliability in the two 60-s power output tests (coefficient of variation = 3.0%) and no significant difference in peak oxygen uptake in the two 6-min all-out tests (coefficient of variation = 2.4%). There was a strong correlation between the absolute (W) and relative power (W x kg(-1)) output in the 6-min double poling ergometer test and the double poling performance on snow (r = 0.86 and 0.89 respectively; both P < 0.05). In conclusion, our results show that the double poling ergometer has both high reliability and validity. However, the power calculated at the flywheel underestimated the total power produced and needs to be corrected for in ergonomic estimations. PMID:17899473

  13. Decomposing cross-country differences in levels of obesity and overweight: does the social environment matter?

    PubMed

    Font, Joan Costa; Fabbri, Daniele; Gil, Joan

    2010-04-01

    This paper examines the influence of environmental factors on weight gain and obesity. We take advantage of a markedly different pattern of obesity between Italy in Spain to undertake a non-linear decomposition analysis of differences in the prevalence of overweight and obesity between the two countries. The analysis is based on cross-sectional national surveys for 2003. We have attempted to isolate the influence of lifestyle factors, socio-economic and socio-environmental effects in explaining cross-country differences in BMI status. Our findings suggest that when the social environment (proxied by different measures of peer effects and regional BMI) is not controlled for, we explain about 27-42% of the overall Spain-to-Italy overweight and obesity gap. Differences in eating habits and education between the two countries are the main predictors of the gaps in obesity and overweight. However, when social environment is controlled for, our estimates explain between 76 and 92% of the obesity and overweight gap and the effect of eating habits are wiped out. These results suggest healthy body weight depends on cultural or environmental triggers that operate through individual level health production determinants.

  14. Mechanical behaviour of cross-country ski racing poles during double poling.

    PubMed

    Stöggl, Thomas; Karlöf, Lars

    2013-11-01

    The purpose of this study was to evaluate the behaviour of cross-country ski poles during double poling on a treadmill using three-dimensional kinematics. The results were compared with standard laboratory tests of the pole manufacturers. A total of 18 skiers were analysed at two speeds (85% and 95% of the maximal speed) at grades of 1.5% and 7%. Variables describing cycle characteristics, bending stiffness, bending behaviour, and trajectories of the pole markers were analysed. Triangular-shaped poles demonstrated the greatest stiffness and lowest variability in maximal bending. Softer poles demonstrated greater variability in bending behaviour and lost ground contact at high skiing speeds, which for some skiers resulted in failure to complete high-speed tests. Considerable variations in pole behaviour for similar poles between skiers were observed, which might be attributed to differences in technique, indicating that mechanical properties of the poles did not exclusively determine pole behaviour in the dynamic situation. The greatest magnitude of pole bending was in the middle part of the pole, which differed from the standard static pole analysis of the manufacturer. Increases in grade demonstrated the greatest effect on pole bending. Distinct differences from the pole manufacturers' laboratory measures were apparent, suggesting that basic pole testing might be adapted.

  15. Biomechanical and energetic determinants of technique selection in classical cross-country skiing.

    PubMed

    Pellegrini, Barbara; Zoppirolli, Chiara; Bortolan, Lorenzo; Holmberg, Hans-Christer; Zamparo, Paola; Schena, Federico

    2013-12-01

    Classical cross-country skiing can be performed using three main techniques: diagonal stride (DS), double poling (DP), and double poling with kick (DK). Similar to other forms of human and animal gait, it is currently unclear whether technique selection occurs to minimize metabolic cost or to keep some mechanical factors below a given threshold. The aim of this study was to find the determinants of technique selection. Ten male athletes roller skied on a treadmill at different slopes (from 0° to 7° at 10km/h) and speeds (from 6 to 18km/h at 2°). The technique preferred by skiers was gathered for every proposed condition. Biomechanical parameters and metabolic cost were then measured for each condition and technique. Skiers preferred DP for skiing on the flat and they transitioned to DK and then to DS with increasing slope steepness, when increasing speed all skiers preferred DP. Data suggested that selections mainly occur to remain below a threshold of poling force. Second, critically low values of leg thrust time may limit the use of leg-based techniques at high speeds. A small role has been identified for the metabolic cost of locomotion, which determined the selection of DP for flat skiing.

  16. Biomechanical analysis of different starting strategies utilized during cross-country skiing starts.

    PubMed

    Wiltmann, Victor Wennemar; Holmberg, Hans-Christer; Pelttari, Pasi; Mikkola, Jussi; Häkkinen, Keijo; Ohtonen, Olli; Linnamo, Vesa

    2016-11-01

    The present study was designed to analyse and compare the kinetics and kinematics associated with three different starting strategies during classic cross-country ski racing. Inside a ski tunnel, 12 elite male skiers performed three sets of three 38 m starts. Each set included one start using: double poling only (DP), diagonal stride only (DIA) and freely chosen (FREE) (i.e. where subjects used the strategy or combination of strategies they felt was fastest) in random order. The first 18 m was performed on a series of force plates that measured horizontal and vertical forces followed by 20 m of a standard snow track. Additionally, cycle characteristics and joint angles were measured. DIA and FREE were faster over 38 m than DP (P < .01). Net horizontal impulse (taking into account both positive and negative impulses) 5-10 m after the start was lower during DP than during DIA and FREE (both P < .05). All subjects skied faster when using only DIA for the entire 38 m. Furthermore, the sum duration and frequency of propulsive contacts over the first 18 m was less in DP than DIA and FREE (P < .01). In conclusion, differences between the starting strategies examined was especially pronounced during the initial cycles. Transition from DIA to DP during the start also slowed the skiers, but optimal timing for such a transition was not elucidated.

  17. A reappraisal of success factors for Olympic cross-country skiing.

    PubMed

    Sandbakk, Øyvind; Holmberg, Hans-Christer

    2014-01-01

    Cross-country (XC) skiing has been an Olympic event since the first Winter Games in Chamonix, France, in 1924. Due to more effective training and tremendous improvements in equipment and track preparation, the speed of Olympic XC-ski races has increased more than that of any other Olympic endurance sport. Moreover, pursuit, mass-start, and sprint races have been introduced. Indeed, 10 of the 12 current Olympic competitions in XC skiing involve mass starts, in which tactics play a major role and the outcome is often decided in the final sprint. Accordingly, reappraisal of the success factors for performance in this context is required. The very high aerobic capacity (VO2max) of many of today's world-class skiers is similar that of their predecessors. At the same time, the new events provide more opportunities to profit from anaerobic capacity, upper-body power, high-speed techniques, and "tactical flexibility." The wide range of speeds and slopes involved in XC skiing requires skiers to continuously alternate between and adapt different subtechniques during a race. This technical complexity places a premium on efficiency. The relative amounts of endurance training performed at different levels of intensity have remained essentially constant during the past 4 decades. However, in preparation for the Sochi Olympics in 2014, XC skiers are performing more endurance training on roller skis on competition-specific terrain, placing greater focus on upper-body power and more systematically performing strength training and skiing at high speeds than previously.

  18. Multi-dimensional coordination in cross-country skiing analyzed using self-organizing maps.

    PubMed

    Lamb, Peter F; Bartlett, Roger; Lindinger, Stefan; Kennedy, Gavin

    2014-02-01

    This study sought to ascertain how multi-dimensional coordination patterns changed with five poling speeds for 12 National Standard cross-country skiers during roller skiing on a treadmill. Self-organizing maps (SOMs), a type of artificial neural network, were used to map the multi-dimensional time series data on to a two-dimensional output grid. The trajectories of the best-matching nodes of the output were then used as a collective variable to train a second SOM to produce attractor diagrams and attractor surfaces to study coordination stability. Although four skiers had uni-modal basins of attraction that evolved gradually with changing speed, the other eight had two or three basins of attraction as poling speed changed. Two skiers showed bi-modal basins of attraction at some speeds, an example of degeneracy. What was most clearly evident was that different skiers showed different coordination dynamics for this skill as poling speed changed: inter-skier variability was the rule rather than an exception. The SOM analysis showed that coordination was much more variable in response to changing speeds compared to outcome variables such as poling frequency and cycle length.

  19. Identification of cross-country skiing movement patterns using micro-sensors.

    PubMed

    Marsland, Finn; Lyons, Keith; Anson, Judith; Waddington, Gordon; Macintosh, Colin; Chapman, Dale

    2012-01-01

    This study investigated the potential of micro-sensors for use in the identification of the main movement patterns used in cross-country skiing. Data were collected from four elite international and four Australian athletes in Europe and in Australia using a MinimaxX™ unit containing accelerometer, gyroscope and GPS sensors. Athletes performed four skating techniques and three classical techniques on snow at moderate velocity. Data from a single micro-sensor unit positioned in the centre of the upper back was sufficient to visually identify cyclical movement patterns for each technique. The general patterns for each technique were identified clearly across all athletes while at the same time distinctive characteristics for individual athletes were observed. Differences in speed, snow condition and gradient of terrain were not controlled in this study and these factors could have an effect on the data patterns. Development of algorithms to process the micro-sensor data into kinematic measurements would provide coaches and scientists with a valuable performance analysis tool. Further research is needed to develop such algorithms and to determine whether the patterns are consistent across a range of different speeds, snow conditions and terrain, and for skiers of differing ability.

  20. Analysis of a simulated sprint competition in classical cross country skiing.

    PubMed

    Stöggl, T; Lindinger, S; Müller, E

    2007-08-01

    The objectives of this project were first to analyze the physiological response of a classical cross country (XC) skiing sprint competition, second, to examine the relationships of kinematic and physiological variables with sprint performance and third, to test the hypothesis that maximal speed in double poling (DP) and diagonal stride (DIAG) predicts sprint performance. Twelve elite skiers performed a treadmill-based simulation of a sprint competition that included two maximal speed tests (DP, DIAG), a test and three sprint heats over a 3.5-h period. VO(2), lactate, heart rate (HR) and kinematic variables were measured. Maximal DP and DIAG speed, the level of repeatedly produced lactate values and skiing technical aspects positively correlated with sprint performance. Fastest skiers produced longer cycle lengths in all techniques at equal poling frequency. VO(2) variables showed no correlation to sprint performance. VO(2), tidal volume (VT), and lactate decreased over the heats. XC-sprint performance in classical style depends on speed abilities, technique use, fatigue resistance, and anaerobic capacity. The relationship of maximal speed with sprint performance suggests (a) integrating maximal speed tests in XC sprint diagnostics and (b) emphasizing training models for XC skiing-specific speed abilities to improve performance in XC skiing sprint.

  1. Effects of fatigue on inter-cycle variability in cross-country skiing.

    PubMed

    Cignetti, F; Schena, F; Rouard, A

    2009-07-22

    The aim of the study was to examine the inter-cycle variability in cross-country skiing gait and its evolution with fatigue. Both issues were investigated to understand the flexibility capabilities of the neuromuscular system. Four women and four men skied on a treadmill, up to exhaustion. The angular displacements of the arms and legs movements were obtained for 40s period at the beginning and end of the skiing test. Mean inter-cycle standard deviation (SD(c)), largest Lyapunov exponent (lambda(1)) and correlation dimension (D(c)) were computed for each time series and surrogate counterpart to evaluate the magnitude and nature of the variability. For any experimental time series, lambda(1) was positive, D(c) greater than 1 and both were found to be different from their surrogate counterparts, confirming that the temporal variations of the data had a deterministic origin. More, larger SD(c), D(c) and lambda(1) values were observed at the end of the test, indicating more variability, noise and local dynamic instability in the data with fatigue. Hence, the fluctuations of limb angular displacements displayed a chaotic behavior, which reflected flexibility of the neuromuscular system to adapt to possible perturbations during skiing. However, such chaotic behavior degraded with fatigue, making the neuromuscular system less adaptable and more unstable.

  2. Poling force analysis in diagonal stride at different grades in cross country skiers.

    PubMed

    Pellegrini, B; Bortolan, L; Schena, F

    2011-08-01

    The aim of this study was to characterize the dynamic parameters of poling action during low to moderate uphill skiing in the diagonal stride technique. Twelve elite cross country skiers performed an incremental test using roller skis on a treadmill at 9 km/h at seven different grades, from 2° to 8°. The pole ground reaction force and the pole inclination were measured, and the propulsive force component and poling power were then calculated. The duration of the active poling phase remained unchanged, while the recovery time decreased with the increase in the slope. The ratio between propulsive and total poling forces (effectiveness) was approximately 60% and increased with the slope. Multiple regression estimated that approximately 80% of the variation of the poling power across slopes was explained by the increase of the poling force, the residual variation was explained by the decrease of the pole inclination, while a small contribution was provided by the increase of the poling relative to the cycle time. The higher power output required to ski at a steeper slope was partially supplied by a greater contribution of the power generated through the pole that arises not only by an increase of the force exerted but also by an increase of its effectiveness.

  3. Identification of Cross-Country Skiing Movement Patterns Using Micro-Sensors

    PubMed Central

    Marsland, Finn; Lyons, Keith; Anson, Judith; Waddington, Gordon; Macintosh, Colin; Chapman, Dale

    2012-01-01

    This study investigated the potential of micro-sensors for use in the identification of the main movement patterns used in cross-country skiing. Data were collected from four elite international and four Australian athletes in Europe and in Australia using a MinimaxX™ unit containing accelerometer, gyroscope and GPS sensors. Athletes performed four skating techniques and three classical techniques on snow at moderate velocity. Data from a single micro-sensor unit positioned in the centre of the upper back was sufficient to visually identify cyclical movement patterns for each technique. The general patterns for each technique were identified clearly across all athletes while at the same time distinctive characteristics for individual athletes were observed. Differences in speed, snow condition and gradient of terrain were not controlled in this study and these factors could have an effect on the data patterns. Development of algorithms to process the micro-sensor data into kinematic measurements would provide coaches and scientists with a valuable performance analysis tool. Further research is needed to develop such algorithms and to determine whether the patterns are consistent across a range of different speeds, snow conditions and terrain, and for skiers of differing ability. PMID:22666075

  4. The effects of skiing velocity on mechanical aspects of diagonal cross-country skiing.

    PubMed

    Andersson, Erik; Pellegrini, Barbara; Sandbakk, Oyvind; Stüggl, Thomas; Holmberg, Hans-Christer

    2014-09-01

    Cycle and force characteristics were examined in 11 elite male cross-country skiers using the diagonal stride technique while skiing uphill (7.5°) on snow at moderate (3.5 ± 0.3 m/s), high (4.5 ± 0.4 m/s), and maximal (5.6 ± 0.6 m/s) velocities. Video analysis (50 Hz) was combined with plantar (leg) force (100 Hz), pole force (1,500 Hz), and photocell measurements. Both cycle rate and cycle length increased from moderate to high velocity, while cycle rate increased and cycle length decreased at maximal compared to high velocity. The kick time decreased 26% from moderate to maximal velocity, reaching 0.14 s at maximal. The relative kick and gliding times were only altered at maximal velocity, where these were longer and shorter, respectively. The rate of force development increased with higher velocity. At maximal velocity, sprint-specialists were 14% faster than distance-specialists due to greater cycle rate, peak leg force, and rate of leg force development. In conclusion, large peak leg forces were applied rapidly across all velocities and the shorter relative gliding and longer relative kick phases at maximal velocity allow maintenance of kick duration for force generation. These results emphasise the importance of rapid leg force generation in diagonal skiing.

  5. MTB-DR-RIF 9G test: Detection and discrimination of tuberculosis and multi-drug resistant tuberculosis strains.

    PubMed

    Song, Keum-Soo; Nimse, Satish Balasaheb; Cho, Nam Hoon; Sung, Nackmoon; Kim, Hee-Jin; Yang, Jeongseong; Kim, Taisun

    2015-12-01

    This report describes the evaluation of the novel MTB-DR-RIF 9G test for the accurate detection and discrimination of Mycobacterium tuberculosis (MTB) and rifampicin-resistant M. tuberculosis (MTB-DR-RIF) in the clinical samples. The procedure included the amplification of a nucleotide fragment of the rpoB gene of the MTB and MTB-DR-RIF strains and their hybridization with the immobilized probes. The MTB-DR-RIF 9G test was evaluated for its ability to detect and discriminate MTB and MTB-DR-RIF strains in 113 known clinical samples. The accuracy of the MTB-DR-RIF 9G test was determined by comparing its results with sequencing analysis and drug susceptibility testing. The sensitivity and specificity of the MTB-DR-RIF 9G test at 95% confidence interval were found to be 95.4% (89.5-98.5) and 100% (69.2-100), respectively. The positive predictive value and negative predictive value of the MTB-DR-RIF 9G test at 95% confidence interval were found to be 100% (85.0-95.9) and 66.7% (38.4-88.18), respectively. Sequencing analysis of all samples indicated that the mutations present in the regions identified with the MTB-DR-RIF 9G assay can be detected accurately.

  6. Mass Spectrometric Identification of Mtb81, a Novel Serological Marker for Tuberculosis

    PubMed Central

    Hendrickson, Ronald C.; Douglass, John F.; Reynolds, Lisa D.; McNeill, Patricia D.; Carter, Darrick; Reed, Steven G.; Houghton, Raymond L.

    2000-01-01

    We have used serological proteome analysis in conjunction with tandem mass spectrometry to identify and sequence a novel protein, Mtb81, which may be useful for the diagnosis of tuberculosis (TB), especially for patients coinfected with human immunodeficiency virus (HIV). Recombinant Mtb81 was tested by an enzyme-linked immunosorbent assay to detect antibodies in 25 of 27 TB patients (92%) seropositive for HIV as well as in 38 of 67 individuals (57%) who were TB positive alone. No reactivity was observed in 11 of 11 individuals (100%) who were HIV seropositive alone. In addition, neither sera from purified protein derivative (PPD)-negative (0 of 29) nor sera from healthy (0 of 45) blood donors tested positive with Mtb81. Only 2 of 57 of PPD-positive individuals tested positive with Mtb81. Sera from individuals with smear-positive TB and seropositive for HIV but who had tested negative for TB in the 38-kDa antigen immunodiagnostic assay were also tested for reactivity against Mtb81, as were sera from individuals with lung cancer and pneumonia. Mtb81 reacted with 26 of 37 HIV+ TB+ sera (70%) in this group, compared to 2 of 37 (5%) that reacted with the 38-kDa antigen. Together, these results demonstrate that Mtb81 may be a promising complementary antigen for the serodiagnosis of TB. PMID:10835002

  7. Fibrofatty Band-Associated Small Bowel Obstruction After Marathon Running

    PubMed Central

    Sunder Raj, Lawrence

    2016-01-01

    We report a 57-year-old man who developed subacute small bowel obstruction after running a marathon. A fibrofatty band was identified restricting the terminal ileum upon subsequent imaging. Surgical division of the band resulted in complete resolution of the patient’s symptoms. Fibrofatty bands are embryonic remnants of the vitellointestinal duct and have not previously been reported to cause small bowel obstruction at the terminal ileum. We discuss the origin of remnant fibrofatty bands and physiological impact of running a marathon upon the gastrointestinal tract that would have contributed to development of subacute small bowel obstruction. PMID:27800517

  8. Anti-VEGF in a Marathon Runner's Retinopathy Case

    PubMed Central

    Soon, Alexander Kahjun

    2016-01-01

    Central retinal vein occlusion (CRVO) is one of the most common retinal vascular disorders. Intense exercise associated CRVO have been described in otherwise healthy young patients. We describe a case of a young male ultramarathoner who presented with a CRVO, presumably associated with dehydration, making part of a marathon runner's retinopathy. Resolution of macular edema and subretinal fluid, with visual acuity improvement, was observed after 3 monthly injections of ranibizumab. Our case suggests that dehydration could be involved in the mechanism of CRVO in healthy young patients and ranibizumab may be an effective treatment option for marathon runner's retinopathy. PMID:27418990

  9. Cross-Country Variation in Adult Skills Inequality: Why Are Skill Levels and Opportunities so Unequal in Anglophone Countries?

    ERIC Educational Resources Information Center

    Green, Andy; Green, Francis; Pensiero, Nicola

    2015-01-01

    This article examines cross-country variations in adult skills inequality and asks why skills in Anglophone countries are so unequal. Drawing on the Organization for Economic Cooperation and Development's recent Survey of Adult Skills and other surveys, it investigates the differences across countries and country groups in inequality in both…

  10. Muscle size, quality, and body composition: characteristics of division I cross-country runners.

    PubMed

    Roelofs, Erica J; Smith-Ryan, Abbie E; Melvin, Malia N; Wingfield, Hailee L; Trexler, Eric T; Walker, Nina

    2015-02-01

    The primary purpose of this study was to identify the relationship between muscle cross-sectional area (mCSA), echo intensity (EI), and body composition of Division I cross-country runners. The secondary purpose was to examine differences in these variables in athletes stratified based on stress-fracture (SFx) history. Thirty-six athletes were stratified based on sex and SFx history. A panoramic scan vastus lateralis was performed using a GE Logiq-e B-mode ultrasound. Echo intensity and mCSA were determined from the scan using a grayscale imaging software (ImageJ). Body composition measures were determined using dual-energy x-ray absorptiometry. For females, mCSA was significantly correlated with left leg lean mass (LM; R = 0.54) and EI (R = -0.57). Lean mass was significantly correlated with bone mineral density (BMD; R = 0.58) and bone mineral content (BMC; R = 0.56), whereas BMC was also correlated with leg LM (R = 0.72). For males, mCSA was significantly correlated with leg LM (R = 0.66), BMD (R = 0.50), and BMC (R = 0.54). Leg LM was significantly correlated with BMD (R = 0.53) and BMC (R = 0.77). Personal best times for males were significantly correlated with fat mass (R = 0.489) and %fat (R = 0.556) for the 10- and 5-km races, respectively. Female and male athletes with a history of SFx were not significantly different across any variables when compared with athletes with no history. These correlations suggest that more muscle mass may associate with higher BMD and BMC for stronger bone structure. Modifications in training strategies to include heavy resistance training and plyometrics may be advantageous for preventing risk factors associated with SFx reoccurrence.

  11. Seatbelt wearing rates in middle income countries: a cross-country analysis.

    PubMed

    Vecino-Ortiz, Andres I; Bishai, David; Chandran, Aruna; Bhalla, Kavi; Bachani, Abdulgafoor M; Gupta, Shivam; Slyunkina, Ekaterina; Hyder, Adnan A

    2014-10-01

    In settings with low seatbelt use prevalence, self-reported seatbelt use estimates often lack validity, and routine observational studies are scarce. In this paper, we aim to describe the prevalence of seatbelt use and associated factors in drivers and front-seat passengers across eight sites in four countries (Egypt, Mexico, Russia, Turkey) using observational studies as well as to produce estimates of country-level and site-level variance. As part of the Bloomberg Philanthropies Global Road Safety Program, data on driver and passenger seatbelt use across four middle-income countries was collected between October 2010 and May 2011 (n=122,931 vehicles). Logistic regression and Intraclass Correlation Coefficient analyses for sites- and country-level clustering were performed. We found high variability of seatbelt wearing rates ranging from 4 to 72% in drivers and 3-50% in front-seat passengers. Overall, average seatbelt wearing rates were low (under 60% in most sites). At the individual level, older and female drivers were more likely to wear seatbelts, as well as drivers of vehicles transiting at times of increased vehicle flow. We also found that 26-32% and 37-41% of the variance in seatbelt use among drivers and front-seat passengers respectively was explained by differences across sites and countries. Our results demonstrate that there is room for improvement on seatbelt use in middle-income countries and that standardized cross-country studies on road safety risk factors are feasible, providing valuable information for prevention and monitoring activities. PMID:24906165

  12. Production activities and economic dependency by age and gender in Europe: A cross-country comparison

    PubMed Central

    Hammer, Bernhard; Prskawetz, Alexia; Freund, Inga

    2015-01-01

    We compare selected European countries using an economic dependency ratio which emphasizes the role of age-specific levels of production and consumption. Our analysis reveals large differences in the age- and gender-specific level and type of production activities across selected European countries and identifies possible strategies to adjust age-specific economic behaviour to an ageing population. The cross-country differences in economic dependency of children and elderly persons are largely determined by the age at which people enter, respectively exit, the labour market. The ability of the working age population to support children and elderly persons in turn is strongly influenced by the participation of women in paid work. We also provide a measure for the age-specific production and consumption in form of unpaid household work. The inclusion of unpaid household work leads to a decrease of the gender differences in production activities and indicates that the working age population supports children and elderly persons not only through monetary transfers but also through services produced by unpaid work (e.g. childcare, cooking, cleaning…). Given the available data, we cannot distinguish the age profile of consumption by gender and have to assume – in case of unpaid work - that each member of the household consumes the same. Hence, our results have to be regarded as a first approximation only. Our paper aims to argue that a reform of the welfare system needs to take into account not only public transfers but also private transfers, in particular the transfers in form of goods and services produced through unpaid household work. PMID:26110107

  13. Gait models and mechanical energy in three cross-country skiing techniques.

    PubMed

    Pellegrini, Barbara; Zoppirolli, Chiara; Bortolan, Lorenzo; Zamparo, Paola; Schena, Federico

    2014-11-01

    Fluctuations in mechanical energy of the body center of mass (COM) have been widely analyzed when investigating different gaits in human and animal locomotion. We applied this approach to estimate the mechanical work in cross-country skiing and to identify the fundamental mechanisms of this particular form of locomotion. We acquired movements of body segments, skis, poles and plantar pressures for eight skiers while they roller skied on a treadmill at 14 km h(-1) and a 2 deg slope using three different techniques (diagonal stride, DS; double poling, DP; double poling with kick, DK). The work associated with kinetic energy (KE) changes of COM was not different between techniques; the work against gravity associated with potential energy (PE) changes was higher for DP than for DK and was lowest for DS. Mechanical work against the external environment was 0.87 J m(-1) kg(-1) for DS, 0.70 J m(-1) kg(-1) for DP and 0.79 J m(-1) kg(-1) for DK. The work done to overcome frictional forces, which is negligible in walking and running, was 17.8%, 32.3% and 24.8% of external mechanical work for DS, DP and DK, respectively. The pendulum-like recovery (R%) between PE and KE was ~45%, ~26% and ~9% for DP, DK and DS, respectively, but energy losses by friction are not accounted for in this computation. The pattern of fluctuations of PE and KE indicates that DS can be described as a 'grounded running', where aerial phases are substituted by ski gliding phases, DP can be described as a pendular gait, whereas DK is a combination of both. PMID:25355851

  14. Biomechanical validation of a specific upper body training and testing drill in cross-country skiing.

    PubMed

    Stöggl, Thomas; Lindinger, Stefan; Müller, Erich

    2006-01-01

    The aim of this study was to perform a biomechanical validation of a double poling imitation drill on a rollerboard. Six elite cross-country skiers performed three imitation drill trials at maximal speed at 13 degrees inclination and in double poling on roller skis on a paved road of 3 degrees. Pole and strap forces, elbow and hip angles and EMG activity of eight upper body muscles were measured. Force curves showed similar characteristics, except for impact force occurring only at pole plant in double poling on roller skis. Double poling on a rollerboard includes an eccentric roll-down phase not appearing in double polling on roller skis. Forces on the rollerboard were similar to those on roller skis. Courses of the elbow angles indicated similar shapes, except for the angle at the start of the propulsion phase and, consequently, during flexion (p < 0.01). Propulsion time and cycle duration were longer and frequency lower on the rollerboard (all p < 0.001). Muscle activities were not significantly different, except for stronger biceps brachii (p < 0.01) and weaker erector spinae activation (p < 0.05) on the rollerboard. Muscle coordination patterns showed similar onset and offset points of each muscle and comparable activations in both activities, except for biceps brachii. Two movement strategies on the rollerboard were found, which led to small differences in measured variables. The biomechanical validity of double poling on a rollerboard can be judged as moderately high, being aware of the differences in some variables that might be considered in training sessions on the rollerboard, particularly when using intervals with high number of repetitions.

  15. Gait models and mechanical energy in three cross-country skiing techniques.

    PubMed

    Pellegrini, Barbara; Zoppirolli, Chiara; Bortolan, Lorenzo; Zamparo, Paola; Schena, Federico

    2014-11-01

    Fluctuations in mechanical energy of the body center of mass (COM) have been widely analyzed when investigating different gaits in human and animal locomotion. We applied this approach to estimate the mechanical work in cross-country skiing and to identify the fundamental mechanisms of this particular form of locomotion. We acquired movements of body segments, skis, poles and plantar pressures for eight skiers while they roller skied on a treadmill at 14 km h(-1) and a 2 deg slope using three different techniques (diagonal stride, DS; double poling, DP; double poling with kick, DK). The work associated with kinetic energy (KE) changes of COM was not different between techniques; the work against gravity associated with potential energy (PE) changes was higher for DP than for DK and was lowest for DS. Mechanical work against the external environment was 0.87 J m(-1) kg(-1) for DS, 0.70 J m(-1) kg(-1) for DP and 0.79 J m(-1) kg(-1) for DK. The work done to overcome frictional forces, which is negligible in walking and running, was 17.8%, 32.3% and 24.8% of external mechanical work for DS, DP and DK, respectively. The pendulum-like recovery (R%) between PE and KE was ~45%, ~26% and ~9% for DP, DK and DS, respectively, but energy losses by friction are not accounted for in this computation. The pattern of fluctuations of PE and KE indicates that DS can be described as a 'grounded running', where aerial phases are substituted by ski gliding phases, DP can be described as a pendular gait, whereas DK is a combination of both.

  16. Analysis of sprint cross-country skiing using a differential global navigation satellite system.

    PubMed

    Andersson, Erik; Supej, Matej; Sandbakk, Øyvind; Sperlich, Billy; Stöggl, Thomas; Holmberg, Hans-Christer

    2010-10-01

    The purpose was to examine skiing velocities, gear choice (G2-7) and cycle rates during a skating sprint time trial (STT) and their relationships to performance, as well as to examine relationships between aerobic power, body composition and maximal skiing velocity versus STT performance. Nine male elite cross-country skiers performed three tests on snow: (1) Maximum velocity test (V (max)) performed using G3 skating, (2) V (max) test performed using double poling (DP) technique and (3) a STT over 1,425 m. Additional measurements of VO(2max) during roller skiing and body composition using iDXA were made. Differential global navigation satellite system data were used for position and velocity and synchronized with video during STT. The STT encompassed a large velocity range (2.9-12.9 m s(-1)) and multiple transitions (21-34) between skiing gears. Skiing velocity in the uphill sections was related to gear selection between G2 and G3. STT performance was most strongly correlated to uphill time (r = 0.92, P < 0.05), the percentage use of G2 (r = -0.72, P < 0.05), and DP V (max) (r = -0.71, P < 0.05). The velocity decrease in the uphills from lap 1 to lap 2 was correlated with VO(2max) (r = -0.78, P < 0.05). V (max) in DP and G3 were related to percent of racing time using G3. In conclusion, the sprint skiing performance was mainly related to uphill performance, greater use of the G3 technique, and higher DP and G3 maximum velocities. Additionally, VO(2max) was related to the ability to maintain racing velocity in the uphills and lean body mass was related to starting velocity and DP maximal speed.

  17. Deadly Serious: The Boston Marathon Tragedy and Education

    ERIC Educational Resources Information Center

    Harney, John O.

    2013-01-01

    Two bombs exploded at the Boston Marathon on Monday, April 15, killing three and injuring more than 260. The pressure-cooker bombs sent shrapnel at leg-level, leading to amputations for 15 victims. An immediate concern was how to deal with the feelings of school children whose sense of safety was shattered by the blasts. As the city healed, Boston…

  18. EXERCISE-INDUCED PULMONARY HEMORRHAGE AFTER RUNNING A MARATHON

    EPA Science Inventory

    We report on a healthy 26-year-old male who had an exercise-induced pulmonary hemorrhage (EIPH) within 24 hours of running a marathon. There were no symptoms, abnormalities on exam, or radiographic infiltrates. He routinely participated in bronchoscopy research and the EIPH was e...

  19. Going the extra mile: health care for marathon runners.

    PubMed

    Doherty, Laura

    2010-05-01

    At last year's London Marathon, St John Ambulance (SJA) volunteers treated almost 6,200 casualties from among more than 35,000 runners. In this article, emergency nurse Hazel Mortimer, who regularly works as a volunteer emergency nurse with the SJA, describes her experiences at this year's event and her expectations of the 2012 Olympics.

  20. Repeated Stress Fractures in an Amenorrheic Marathoner: A Case Conference.

    ERIC Educational Resources Information Center

    Sutton, John R.; Nilson, Karen L.

    1989-01-01

    Presents a case conference by 2 experts on the relationship between a 26-year-old marathoner's amenorrhea and her sustained unusual stress fractures in 4 ribs (plus previous similar fractures of the calcaneal, navicular, metatarsal, and tibial bones). The experts conclude that she suffers many manifestations of overtraining. (SM)

  1. Structural style of the Marathon thrust belt, West Texas

    NASA Astrophysics Data System (ADS)

    Hickman, Robert G.; Varga, Robert J.; Altany, Robert M.

    2009-09-01

    The Marathon portion of the Ouachita thrust belt consists of a highly deformed allochthonous wedge of Cambrian-Pennsylvanian slope strata (Marathon facies) that was transported to the northwest and emplaced over Pennsylvanian foredeep sediments. The foredeep strata in turn overlie early-middle Paleozoic shelfal sediments which are deformed by late Paleozoic basement-involved reverse faults. The Dugout Creek thrust is the basal thrust of the allochthon. Shortening in this sheet and overlying sheets is ˜80%. Steep imbricate faults link the Dugout Creek thrust to upper level detachments forming complex duplex zones. Progressive thrusting and shortening within the allochthon folded the upper level detachments and associated thrust sheets. The Caballos Novaculite is the most competent unit within the Marathon facies and controlled development of prominent detachment folds. Deeper imbricate sheets composed of the Late Pennsylvanian foredeep strata, and possibly early-middle Paleozoic shelfal sediments developed concurrently with emplacement of the Marathon allochthon and folded the overlying allochthon. Following termination of thrusting in the earliest Permian, subsidence and deposition shifted northward to the Delaware, Midland and Val Verde foreland basins.

  2. Predicting Benefit from a Gestalt Therapy Marathon Workshop.

    ERIC Educational Resources Information Center

    Healy, James; Dowd, E. Thomas

    1981-01-01

    Tested the utility of the Personal Orientation Inventory (POI), the Myers-Briggs Type Indicator, and the Girona Affect Scale in predicting the outcomes of a marathon Gestalt therapy workshop. Signigicant predictive equations were generated that use the POI to predict gains on the Girona Affect Scale. (Author/RC)

  3. Marathon Group: Changes in Perceived Locus of Control

    ERIC Educational Resources Information Center

    Foulds, Melvin L.; And Others

    1974-01-01

    Fifteen college students participated in a 24-hour marathon group and responded to the Internal-External Scale immediately before and after the experience. The results disclosed significant positive change at the .001 level in perceived locus of internal-external control of reinforcement expectancies in the direction of increased internality.…

  4. Transitions: Preparing Families of Preschoolers for "Marathon Skills".

    ERIC Educational Resources Information Center

    Deitz, Sally J.; Warkala, Catherine Sonen

    1993-01-01

    Skills that families gain in coping with transitions at the early ages of their child with visual impairments provide skills necessary for all the life-stage transitions that follow and, thus, are termed marathon skills. The transition programing of the Lighthouse Child Development Center in New York City is designed to develop those skills. (JDD)

  5. Marathon Group: Changes in Scores on the California Psychological Inventory

    ERIC Educational Resources Information Center

    Foulds, Melvin L.; And Others

    1974-01-01

    Eighteen college students participated in a 24-hour marathon group and responded to the California Psychological Inventory (CPI) immediately before and after the experience. The results disclosed significant positive changes at the .05 level on 11 of 18 scales on this inventory. (Author)

  6. A Gestalt Marathon Workshop: Effects on Extraversion and Neuroticism

    ERIC Educational Resources Information Center

    Foulds, Melvin L.; Hannigan, Patricia S.

    1976-01-01

    College students (N=18) participated in a 24-hour marathon gestalt workshop and responded to the Eysenck Personality Inventory before and after the event. Results revealed a significant positive change at the .01 level on a measure of neuroticism-stability and no change on a measure of extroversion-introversion. (Author)

  7. Marathon Group Counseling with Illicit Drug Users: Analysis of Content.

    ERIC Educational Resources Information Center

    Page, Richard C.; Wills, Judy

    1983-01-01

    Summarized a 16-hour marathon group for illicit drug users (N=12) in residential treatment. Content analysis showed the group spent more time on interpersonal relationships and relatively little time on group process. Drug users were able to successfully participate in therapeutic group discussions involving self-investment. (JAC)

  8. Effects of Marathon Group Therapy on Trait and State Anxiety

    ERIC Educational Resources Information Center

    Kilmann, Peter R.; Auerbach, Stephen M.

    1974-01-01

    Results were interpreted as supporting Spielberger's notion that trait anxiety reflects a dispositional tendency to respond with anxiety in ego-threat situations and as suggesting that personality trait measures may be more relevant outcome indicators than measures of transitory mood states in marathon therapy research. (Author)

  9. Similarities and Differences of Marathon and Ongoing Strength Groups.

    ERIC Educational Resources Information Center

    Barrick, Marilyn C.; Creveling, Patricia

    Marathon groups offer individuals an opportunity to engage in intensified, authentic personal encounter with each other in a small group setting, usually with 10-15 persons in a group. This is a report of tentative findings at the Student Life Center, University of Colorado. There were three matched groups, each with nine sophomores. The first…

  10. Aspirin Risks in Perspective: A Comparison against Marathon Running

    ERIC Educational Resources Information Center

    Morgan, Gareth

    2014-01-01

    Aspirin has public health potential to reduce the risk of ischaemic vascular events and sporadic cancer. One objection to the wider use of aspirin for primary prevention, however, is the undesirable effects of the medicine, which include increasing risk of bleeding and haemorrhagic stroke. Marathons also carry risks of serious events such as…

  11. DIAGNOSTIC TEST OF SPUTUM GENEXPERT MTB/RIF FOR SMEAR NEGATIVE PULMONARY TUBERCULOSIS.

    PubMed

    Reechaipichitkul, Wipa; Phetsuriyawong, Attawoot; Chaimanee, Prajuab; Ananta, Pimjai

    2016-05-01

    The objective of this study was to evaluate the performance of the Gene-Xpert MTB/RIF sputum test for diagnosing pulmonary tuberculosis (TB) among patients sputum acid-fast bacillus (AFB) smear negative results in Thailand, a country with a high prevalence of pulmonary tuberculosis. We studied 151 patients who presented to Srinagarind Hospital, Khon Kaen, Thailand with a 2 week or more history of fever and/or cough and an abnormal chest radiograph between 2010 and 2014; these patients had at least 2 negative sputum AFB smear results. Of these, 76 were diagnosed as having either confirmed or probable pulmonary TB: the 32 confirmed cases were those with a positive sputum culture for Mycobacterium tuberculosis (MTB) and the 44 probable case were those with clinical and radiographic findings consistent with TB and who had a response to anti-TB therapy. Seventy-five cases were diagnosed as not having pulmonary TB. Of the 32 patients with a positive sputum culture for MTB, 26 had a positive GeneXpert MTB/RIF sputum test. Compared to sputum culture for MTB the GeneXpert MTB/ RIF test gave a sensitivity of 83.9% (95% CI: 66.3-94.5) and a specificity of 92.1% (95% CI: 83.6-97), a positive predictive value (PPV) of 81.3% (95% CI: 63.6-92.8) and a negative predictive value (NPV) of 93.3% (95% CI: 85.1-97.8). The GeneXpert MTB/RIF test had a fair sensitivity and specificity for diagnosing smear negative pulmonary TB. It may be useful for diagnosing pulmonary TB in patients with a negative sputum AFB smear. The assay is faster than culture and can detect rifampicin resistant strains of MTB. PMID:27405129

  12. A cross-country review of strategies of the German development cooperation to strengthen human resources

    PubMed Central

    Windisch, Ricarda; Wyss, Kaspar; Prytherch, Helen

    2009-01-01

    Background Recent years have seen growing awareness of the importance of human resources for health in health systems and with it an intensifying of the international and national policies in place to steer a response. This paper looks at how governments and donors in five countries – Cameroon, Indonesia, Malawi, Rwanda and Tanzania – have translated such policies into action. More detailed information with regard to initiatives of German development cooperation brings additional depth to the range and entry doors of human resources for health initiatives from the perspective of donor cooperation. Methods This qualitative study systematically presents different approaches and stages to human resources for health development in a cross-country comparison. An important reference to capture implementation at country level was grey literature such as policy documents and programme reports. In-depth interviews along a predefined grid with national and international stakeholders in the five countries provided information on issues related to human resources for health policy processes and implementation. Results All five countries have institutional entities in place and have drawn up national policies to address human resources for health. Only some of the countries have translated policies into strategies with defined targets and national programmes with budgets and operational plans. Traditional approaches of supporting training for individual health professionals continue to dominate. In some cases partners have played an advocacy and technical role to promote human resources for health development at the highest political levels, but usually they still focus on the provision of ad hoc training within their programmes, which may not be in line with national human resources for health development efforts or may even be counterproductive to them. Countries that face an emergency, such as Malawi, have intensified their efforts within a relatively short time and by

  13. Characterization of the work-time relationship during cross-country ski ergometry.

    PubMed

    Fukuda, D H; Hetrick, R P; Kendall, K L; Smith-Ryan, A E; Jackson, M E; Stout, J R

    2014-01-01

    The purpose of this study was to examine the validity and reliability of estimated parameters of the work-time relationship during cross-country ski ergometry using the traditional multi-trial critical power (CP) test and a 3 min 'all-out' test (3MT). Fourteen recreationally active male participants (mean ± SD; age: 22.14 ± 2.85 yrs; height: 177.09 ± 6.57 cm; weight: 85.68 ± 13.56 kg) completed three testing visits. All testing was conducted using an upper-body ergometer (SkiErg, Concept2, Inc., Morrisville, VT). A graded exercise test was used to determined maximal oxygen uptake (VO2peak). Two separate 3MT sessions were used to determine oxygen uptake (VO23MT), end-test power (EP), work above end-test power (WEP) and end stroke rate (ESR). Additionally, three time trials completed in a single day at simulated distances of 300 m, 650 m and 1000 m were used to estimate CP, W' and critical stroke rate (CSR). VO2peak (3.65 ± 0.50 l · min(-1)) and VO23MT (3.59 ± 0.4 l · min(-1)) were not significantly different (p = 0.162). Intraclass correlation coefficients for EP, WEP and ESR were 0.809, 0.611 and 0.783, respectively. EP (148 ± 33 W) and CP (157 ± 49 W), were not significantly different between the testing methodologies (p = 0.290) and were highly correlated (r = 0.780). WEP (8.4 ± 3.0 kJ) and W' (8.3 ± 3.0 kJ) were similar (p = 0.947) but not related (r = 0.119), while ESR (45 ± 7 spm) and CSR (47 ± 7 spm) values were not significantly different (p = 0.238) and moderately correlated (r = 0.498). The 3MT using ski ergometry was shown to produce concurrently valid results with the traditional multi-trial CP test for CP and CSR, but not W', and elicited similar maximal oxygen uptake values when compared to a graded exercise test.

  14. Participation and performance trends of East-African runners in Swiss half-marathons and marathons held between 2000 and 2010

    PubMed Central

    2013-01-01

    Background This study examined the changes in participation, performance and age of East African runners competing in half-marathons and marathons held in Switzerland between 2000 and 2010. Methods Race times, sex, age and origin of East African versus Non-African finishers of half-marathon and marathon finishers were analyzed. Results Across time, the number of Kenyan and Ethiopian finishers remained stable (P > 0.05) while the number of Non-African finishers increased for both women and men in both half-marathons and marathons (P < 0.05). In half-marathons, the top ten African women (71 ± 1.4 min) and top three (62.3 ± 0.6 min) and top ten (62.8 ± 0.4 min) African men were faster than their Non-African counterparts (P < 0.05). In marathons, however, there was no difference in race times between the top three African men (130.0 ± 0.0 min) and women (151.7 ± 2.5 min) compared to Non-African men (129.0 ± 1.0 min) and women (150.7 ± 1.2 min) (P > 0.05). In half-marathons and marathons was no difference in age between the best Non-African and the best African runners (P > 0.05). Conclusions During the last decade in Switzerland, the participation of Kenyan and Ethiopian runners in half- and full- marathons remained stable. In marathons there was no difference in age and performance between the top African and the top Non-African runners. Regarding half-marathons, the top African runners were faster but not younger than the top Non-African runners. Future insight should be gained by comparing the present results with participation, performance and age trends for East African runners competing in marathons held in larger countries. PMID:24289794

  15. A case of pseudo–angina pectoris from a pectoralis minor trigger point caused by cross-country skiing

    PubMed Central

    Lawson, Gordon E.; Hung, Laurie Y.; Ko, Gordon D.; Laframboise, Michelle A.

    2011-01-01

    Objective The aim of this article is to illustrate the pectoralis minor muscle as a possible pain source in patients with anterior chest pain, especially those who are known to be beginner cross-country skiers. Clinical Features A 58-year-old man presented with anterior chest pain and normal cardiac examination findings. Upon history taking and physical examination, the chest pain was determined to be caused by active trigger points in the pectoralis minor muscle. Intervention and Outcome The patient was treated with Graston Technique and cross-country skiing technique advice. The subject's symptoms improved significantly after 2 treatments and completely resolved after 4 treatments. Conclusion This case demonstrates the importance of differential diagnosis and mechanism of injury in regard to chest pain and that chiropractic management can be successful when addressing patients with chest wall pain of musculoskeletal origin. PMID:22014906

  16. Analysis of Classical Time-Trial Performance and Technique-Specific Physiological Determinants in Elite Female Cross-Country Skiers.

    PubMed

    Sandbakk, Øyvind; Losnegard, Thomas; Skattebo, Øyvind; Hegge, Ann M; Tønnessen, Espen; Kocbach, Jan

    2016-01-01

    The present study investigated the contribution of performance on uphill, flat, and downhill sections to overall performance in an international 10-km classical time-trial in elite female cross-country skiers, as well as the relationships between performance on snow and laboratory-measured physiological variables in the double poling (DP) and diagonal (DIA) techniques. Ten elite female cross-country skiers were continuously measured by a global positioning system device during an international 10-km cross-country skiing time-trial in the classical technique. One month prior to the race, all skiers performed a 5-min submaximal and 3-min self-paced performance test while roller skiing on a treadmill, both in the DP and DIA techniques. The time spent on uphill (r = 0.98) and flat (r = 0.91) sections of the race correlated most strongly with the overall 10-km performance (both p < 0.05). Approximately 56% of the racing time was spent uphill, and stepwise multiple regression revealed that uphill time explained 95.5% of the variance in overall performance (p < 0.001). Distance covered during the 3-min roller-skiing test and body-mass normalized peak oxygen uptake (VO2peak) in both techniques showed the strongest correlations with overall time-trial performance (r = 0.66-0.78), with DP capacity tending to have greatest impact on the flat and DIA capacity on uphill terrain (all p < 0.05). Our present findings reveal that the time spent uphill most strongly determine classical time-trial performance, and that the major portion of the performance differences among elite female cross-country skiers can be explained by variations in technique-specific aerobic power. PMID:27536245

  17. Analysis of Classical Time-Trial Performance and Technique-Specific Physiological Determinants in Elite Female Cross-Country Skiers

    PubMed Central

    Sandbakk, Øyvind; Losnegard, Thomas; Skattebo, Øyvind; Hegge, Ann M.; Tønnessen, Espen; Kocbach, Jan

    2016-01-01

    The present study investigated the contribution of performance on uphill, flat, and downhill sections to overall performance in an international 10-km classical time-trial in elite female cross-country skiers, as well as the relationships between performance on snow and laboratory-measured physiological variables in the double poling (DP) and diagonal (DIA) techniques. Ten elite female cross-country skiers were continuously measured by a global positioning system device during an international 10-km cross-country skiing time-trial in the classical technique. One month prior to the race, all skiers performed a 5-min submaximal and 3-min self-paced performance test while roller skiing on a treadmill, both in the DP and DIA techniques. The time spent on uphill (r = 0.98) and flat (r = 0.91) sections of the race correlated most strongly with the overall 10-km performance (both p < 0.05). Approximately 56% of the racing time was spent uphill, and stepwise multiple regression revealed that uphill time explained 95.5% of the variance in overall performance (p < 0.001). Distance covered during the 3-min roller-skiing test and body-mass normalized peak oxygen uptake (VO2peak) in both techniques showed the strongest correlations with overall time-trial performance (r = 0.66–0.78), with DP capacity tending to have greatest impact on the flat and DIA capacity on uphill terrain (all p < 0.05). Our present findings reveal that the time spent uphill most strongly determine classical time-trial performance, and that the major portion of the performance differences among elite female cross-country skiers can be explained by variations in technique-specific aerobic power. PMID:27536245

  18. Validation of physiological tests in relation to competitive performances in elite male distance cross-country skiing.

    PubMed

    Carlsson, Magnus; Carlsson, Tomas; Hammarström, Daniel; Tiivel, Toomas; Malm, Christer; Tonkonogi, Michail

    2012-06-01

    The purpose of the present study was to establish which physiological test parameters reflects the distance performances in the Swedish National Championships in cross-country skiing (SNC) and the International Ski Federation's ranking points for distance performances (FISdist). The present study also aimed to create multiple regression models to describe skiing performance for the SNC distance races and International Ski Federation's (FIS) ranking. Twelve male, Swedish, national elite, cross-country skiers (maximal oxygen consumption [·VO₂max] = 5.34 ± 0.34 L·min⁻¹) volunteered to participate in the study. Their results in the 2008 SNC (15 km race [SNC15] and 30 km race [SNC30]) and FISdist points were used as performance data. On the week preceding the Championship, subjects completed a test battery consisting of 7 physiological tests: isokinetic knee extension peak torque (PT), vertical jumps (VJ), lactate threshold (LT), ·VO₂max, and 3 double poling tests of different durations (DP20, DP60, and DP360). Correlations were established using Pearson's correlation analysis, and models to describe skiing performance were created using standard multiple linear regression analysis. Significant correlations were found between the performance parameters and test parameters derived from LT, ·VO₂max, and DP60 tests. No correlations with any performance parameter were found for PT, VJ, DP20, and DP360 tests. For FISdist and SNC15, the models explain 81% and 78% of the variance in performance, respectively. No statistically valid regression model was found for SNC30. The results of this study imply that the physiological demands in male elite distance cross-country skiing performances are different in different events. To adequately evaluate a skier's performance ability in distance cross-country skiing, it is necessary to use test parameters and regression models that reflect the specific performance.

  19. Analysis of Classical Time-Trial Performance and Technique-Specific Physiological Determinants in Elite Female Cross-Country Skiers.

    PubMed

    Sandbakk, Øyvind; Losnegard, Thomas; Skattebo, Øyvind; Hegge, Ann M; Tønnessen, Espen; Kocbach, Jan

    2016-01-01

    The present study investigated the contribution of performance on uphill, flat, and downhill sections to overall performance in an international 10-km classical time-trial in elite female cross-country skiers, as well as the relationships between performance on snow and laboratory-measured physiological variables in the double poling (DP) and diagonal (DIA) techniques. Ten elite female cross-country skiers were continuously measured by a global positioning system device during an international 10-km cross-country skiing time-trial in the classical technique. One month prior to the race, all skiers performed a 5-min submaximal and 3-min self-paced performance test while roller skiing on a treadmill, both in the DP and DIA techniques. The time spent on uphill (r = 0.98) and flat (r = 0.91) sections of the race correlated most strongly with the overall 10-km performance (both p < 0.05). Approximately 56% of the racing time was spent uphill, and stepwise multiple regression revealed that uphill time explained 95.5% of the variance in overall performance (p < 0.001). Distance covered during the 3-min roller-skiing test and body-mass normalized peak oxygen uptake (VO2peak) in both techniques showed the strongest correlations with overall time-trial performance (r = 0.66-0.78), with DP capacity tending to have greatest impact on the flat and DIA capacity on uphill terrain (all p < 0.05). Our present findings reveal that the time spent uphill most strongly determine classical time-trial performance, and that the major portion of the performance differences among elite female cross-country skiers can be explained by variations in technique-specific aerobic power.

  20. Results from early programmatic implementation of Xpert MTB/RIF testing in nine countries

    PubMed Central

    2014-01-01

    Background The Xpert MTB/RIF assay has garnered significant interest as a sensitive and rapid diagnostic tool to improve detection of sensitive and drug resistant tuberculosis. However, most existing literature has described the performance of MTB/RIF testing only in study conditions; little information is available on its use in routine case finding. TB REACH is a multi-country initiative focusing on innovative ways to improve case notification. Methods We selected a convenience sample of nine TB REACH projects for inclusion to cover a range of implementers, regions and approaches. Standard quarterly reports and machine data from the first 12 months of MTB/RIF implementation in each project were utilized to analyze patient yields, rifampicin resistance, and failed tests. Data was collected from September 2011 to March 2013. A questionnaire was implemented and semi-structured interviews with project staff were conducted to gather information on user experiences and challenges. Results All projects used MTB/RIF testing for people with suspected TB, as opposed to testing for drug resistance among already diagnosed patients. The projects placed 65 machines (196 modules) in a variety of facilities and employed numerous case-finding strategies and testing algorithms. The projects consumed 47,973 MTB/RIF tests. Of valid tests, 7,195 (16.8%) were positive for MTB. A total of 982 rifampicin resistant results were found (13.6% of positive tests). Of all tests conducted, 10.6% failed. The need for continuous power supply was noted by all projects and most used locally procured solutions. There was considerable heterogeneity in how results were reported and recorded, reflecting the lack of standardized guidance in some countries. Conclusions The findings of this study begin to fill the gaps among guidelines, research findings, and real-world implementation of MTB/RIF testing. Testing with Xpert MTB/RIF detected a large number of people with TB that routine services failed to

  1. Effects of an eight-week training program on upper-body power in women cross-country skiers.

    PubMed

    Downing, Julie J; Wilcox, Anthony R

    2003-11-01

    A distinguishing feature of elite cross-country skiers is their superlative upper-body power (UBP). Recently, roller board training was shown to be superior for improving UBP in cross-country skiers; however, the newly developed wind machine had not yet been tested. The purpose of this study was to determine if wind machine training was as effective as roller board training at increasing UBP. Forty-four women cross-country skiers, age 23-59 years, were matched on initial UBP, measured in watts (W), and placed into 1 of 2 experimental groups (roller board or wind machine). All women underwent 8 weeks of UBP training. Although both groups improved significantly pre-post (p < 0.05) in UBP, t-tests indicated that there was no significant difference (p > 0.05) between the 2 groups' improvements (roller board, pre 74.5 +/- 30.9, post 95.9 +/- 29.8 W; wind machine, pre 74.5 +/- 33.5, post 99.3 +/- 34.3 W). Thus the wind machine was as effective at enhancing UBP as the roller board.

  2. The velocity and energy profiles of elite cross-country skiers executing downhill turns with different radii.

    PubMed

    Sandbakk, Oyvind; Bucher Sandbakk, Silvana; Supej, Matej; Holmberg, Hans-Christer

    2014-01-01

    This study examined the influence of turn radius on velocity and energy profiles when skidding and step turning during more and less effective downhill turns while cross-country skiing. Thirteen elite female cross-country skiers performed single turns with a 9- or 12-m radius using the skidding technique and a 12- or 15-m radius with step turning. Mechanical parameters were monitored using a real-time kinematic Global Navigation Satellite System and video analysis. Step turning was more effective during all phases of a turn, leading to higher velocities than skidding (P < .05). With both techniques, a greater radius was associated with higher velocity (P < .05), but the quality of turning, as assessed on the basis of energy characteristics, was the same. More effective skidding turns involved more pronounced deceleration early in the turn and maintenance of higher velocity thereafter, while more effective step turning involved lower energy dissipation during the latter half of the turn. In conclusion, the single-turn analysis employed here reveals differences in the various techniques chosen by elite cross-country skiers when executing downhill turns of varying radii and can be used to assess the quality of such turns.

  3. A simulation of cross-country skiing on varying terrain by using a mathematical power balance model.

    PubMed

    Moxnes, John F; Sandbakk, Oyvind; Hausken, Kjell

    2013-01-01

    The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual skiing on snow, and calculated the theoretical effect of friction and air drag on skiing performance. As input values in the model, air drag and friction were estimated from the literature, whereas the model included relationships between heart rate, metabolic rate, and work rate based on the treadmill roller-ski testing of an elite cross-country skier. We verified this procedure by testing four models of metabolic rate against experimental data on the treadmill. The experimental data corresponded well with the simulations, with the best fit when work rate was increased on uphill and decreased on downhill terrain. The simulations predicted that skiing time increases by 3%-4% when either friction or air drag increases by 10%. In conclusion, the power balance model was found to be a useful tool for predicting how various factors influence racing performance in cross-country skiing.

  4. Biomechanical comparison of the double-push technique and the conventional skate skiing technique in cross-country sprint skiing.

    PubMed

    Stöggl, Thomas; Müller, Erich; Lindinger, Stefan

    2008-09-01

    The aims of the study were to: (1) adapt the "double-push" technique from inline skating to cross-country skiing; (2) compare this new skiing technique with the conventional skate skiing cross-country technique; and (3) test the hypothesis that the double-push technique improves skiing speed in a short sprint. 13 elite skiers performed maximum-speed sprints over 100 m using the double-push skate skiing technique and using the conventional "V2" skate skiing technique. Pole and plantar forces, knee angle, cycle characteristics, and electromyography of nine lower body muscles were analysed. We found that the double-push technique could be successfully transferred to cross-country skiing, and that this new technique is faster than the conventional skate skiing technique. The double-push technique was 2.9 +/- 2.2% faster (P < 0.001), which corresponds to a time advantage of 0.41 +/- 0.31 s over 100 m. The double-push technique had a longer cycle length and a lower cycle rate, and it was characterized by higher muscle activity, higher knee extension amplitudes and velocities, and higher peak foot forces, especially in the first phase of the push-off. Also, the foot was more loaded laterally in the double-push technique than in the conventional skate skiing technique.

  5. A simulation of cross-country skiing on varying terrain by using a mathematical power balance model

    PubMed Central

    Moxnes, John F; Sandbakk, Øyvind; Hausken, Kjell

    2013-01-01

    The current study simulated cross-country skiing on varying terrain by using a power balance model. By applying the hypothetical inductive deductive method, we compared the simulated position along the track with actual skiing on snow, and calculated the theoretical effect of friction and air drag on skiing performance. As input values in the model, air drag and friction were estimated from the literature, whereas the model included relationships between heart rate, metabolic rate, and work rate based on the treadmill roller-ski testing of an elite cross-country skier. We verified this procedure by testing four models of metabolic rate against experimental data on the treadmill. The experimental data corresponded well with the simulations, with the best fit when work rate was increased on uphill and decreased on downhill terrain. The simulations predicted that skiing time increases by 3%–4% when either friction or air drag increases by 10%. In conclusion, the power balance model was found to be a useful tool for predicting how various factors influence racing performance in cross-country skiing. PMID:24379718

  6. Comparison of ankle kinematics and ground reaction forces between prospectively injured and uninjured collegiate cross country runners.

    PubMed

    Kuhman, Daniel J; Paquette, Max R; Peel, Shelby A; Melcher, Daniel A

    2016-06-01

    Biomechanical comparative studies on running-related injuries have included either currently or retrospectively injured runners. The purpose of this study was to prospectively compare ankle joint and ground reaction force variables between collegiate runners who developed injuries during the cross country season and those who did not. Running gait analyses using a motion capture system and force platform were conducted on 19 collegiate runners prior to the start of their cross country season. Ten runners sustained running-related injuries and 9 remained healthy during the course of the season. Strike index, peak loading rate of the vertical ground reaction force, dorsiflexion range of motion (ROM), eversion ROM, peak eversion angle, peak eversion velocity, and eversion duration from the start of the season were compared between injury groups. Ankle eversion ROM and peak eversion velocity were greater in uninjured runners while peak eversion angle was greater in injured runners. Greater ankle eversion ROM and eversion velocity with lower peak eversion angle may be beneficial in reducing injury risk in collegiate runners. The current data may only be applicable to collegiate cross country runners with similar training and racing schedules and threshold magnitudes of ankle kinematic variables to predict injury risk are still unknown.

  7. Comparison of ankle kinematics and ground reaction forces between prospectively injured and uninjured collegiate cross country runners.

    PubMed

    Kuhman, Daniel J; Paquette, Max R; Peel, Shelby A; Melcher, Daniel A

    2016-06-01

    Biomechanical comparative studies on running-related injuries have included either currently or retrospectively injured runners. The purpose of this study was to prospectively compare ankle joint and ground reaction force variables between collegiate runners who developed injuries during the cross country season and those who did not. Running gait analyses using a motion capture system and force platform were conducted on 19 collegiate runners prior to the start of their cross country season. Ten runners sustained running-related injuries and 9 remained healthy during the course of the season. Strike index, peak loading rate of the vertical ground reaction force, dorsiflexion range of motion (ROM), eversion ROM, peak eversion angle, peak eversion velocity, and eversion duration from the start of the season were compared between injury groups. Ankle eversion ROM and peak eversion velocity were greater in uninjured runners while peak eversion angle was greater in injured runners. Greater ankle eversion ROM and eversion velocity with lower peak eversion angle may be beneficial in reducing injury risk in collegiate runners. The current data may only be applicable to collegiate cross country runners with similar training and racing schedules and threshold magnitudes of ankle kinematic variables to predict injury risk are still unknown. PMID:26827155

  8. Improved marathon performance by in-race nutritional strategy intervention.

    PubMed

    Hansen, Ernst Albin; Emanuelsen, Anders; Gertsen, Robert Mørkegaard; Sørensen S, S R

    2014-12-01

    It was tested whether a marathon was completed faster by applying a scientifically based rather than a freely chosen nutritional strategy. Furthermore, gastrointestinal symptoms were evaluated. Nonelite runners performed a 10 km time trial 7 weeks before Copenhagen Marathon 2013 for estimation of running ability. Based on the time, runners were divided into two similar groups that eventually should perform the marathon by applying the two nutritional strategies. Matched pairs design was applied. Before the marathon, runners were paired based on their prerace running ability. Runners applying the freely chosen nutritional strategy (n = 14; 33.6 ± 9.6 years; 1.83 ± 0.09 m; 77.4 ± 10.6 kg; 45:40 ± 4:32 min for 10 km) could freely choose their in-race intake. Runners applying the scientifically based nutritional strategy (n = 14; 41.9 ± 7.6 years; 1.79 ± 0.11 m; 74.6 ± 14.5 kg; 45:44 ± 4:37 min) were targeting a combined in-race intake of energy gels and water, where the total intake amounted to approximately 0.750 L water, 60 g maltodextrin and glucose, 0.06 g sodium, and 0.09 g caffeine per hr. Gastrointestinal symptoms were assessed by a self-administered postrace questionnaire. Marathon time was 3:49:26 ± 0:25:05 and 3:38:31 ± 0:24:54 hr for runners applying the freely chosen and the scientifically based strategy, respectively (p = .010, effect size=-0.43). Certain runners experienced diverse serious gastrointestinal symptoms, but overall, symptoms were low and not different between groups (p > .05). In conclusion, nonelite runners completed a marathon on average 10:55 min, corresponding to 4.7%, faster by applying a scientifically based rather than a freely chosen nutritional strategy. Furthermore, average values of gastrointestinal symptoms were low and not different between groups. PMID:24901444

  9. A Comparison between Alpine Skiing, Cross-Country Skiing and Indoor Cycling on Cardiorespiratory and Metabolic Response

    PubMed Central

    Stöggl, Thomas; Schwarzl, Christoph; Müller, Edith E.; Nagasaki, Masaru; Stöggl, Julia; Scheiber, Peter; Schönfelder, Martin; Niebauer, Josef

    2016-01-01

    Since physical inactivity especially prevails during winter months, we set out to identify outdoor alternatives to indoor cycling (IC) by comparing the metabolic and cardiorespiratory responses during alpine skiing (AS), cross-country skiing (XCS) and IC and analyse the effects of sex, age and fitness level in this comparison. Twenty one healthy subjects performed alpine skiing (AS), cross-country skiing (XCS), and IC. Oxygen uptake (VO2), total energy expenditure (EE), heart rate (HR), lactate, blood glucose and rate of perceived exertion (RPE) were determined during three 4-min stages of low, moderate and high intensity. During XCS and IC VO2max and EE were higher than during AS. At least 2½ hours of AS are necessary to reach the same EE as during one hour of XCS or IC. HR, VO2, lactate, and RPEarms were highest during XCS, whereas RPEwhole-body was similar and RPElegs lower than during AS and IC, respectively. Weight adjusted VO2 and EE were higher in men than in women while fitness level had no effect. Male, fit and young participants were able to increase their EE and VO2 values more pronounced. Both AS and XCS can be individually tailored to serve as alternatives to IC and may thus help to overcome the winter activity deficit. XCS was found to be the most effective activity for generating a high EE and VO2 while AS was the most demanding activity for the legs. Key points During cross-country skiing and indoor cycling VO2max and energy expenditure were higher than during alpine skiing Approximately 2½ hours of alpine skiing are necessary to reach the same energy expenditure of one hour of cross-country skiing or indoor cycling. Alpine skiing and cross-country skiing can be individually tailored to serve as sports alternatives in winter to activity deficit. By applying different skiing modes as parallel ski steering, carving long radii and short turn skiing, metabolic and cardiorespiratory response can be increased during alpine skiing. Male, fit and young

  10. A Comparison between Alpine Skiing, Cross-Country Skiing and Indoor Cycling on Cardiorespiratory and Metabolic Response.

    PubMed

    Stöggl, Thomas; Schwarzl, Christoph; Müller, Edith E; Nagasaki, Masaru; Stöggl, Julia; Scheiber, Peter; Schönfelder, Martin; Niebauer, Josef

    2016-03-01

    Since physical inactivity especially prevails during winter months, we set out to identify outdoor alternatives to indoor cycling (IC) by comparing the metabolic and cardiorespiratory responses during alpine skiing (AS), cross-country skiing (XCS) and IC and analyse the effects of sex, age and fitness level in this comparison. Twenty one healthy subjects performed alpine skiing (AS), cross-country skiing (XCS), and IC. Oxygen uptake (VO2), total energy expenditure (EE), heart rate (HR), lactate, blood glucose and rate of perceived exertion (RPE) were determined during three 4-min stages of low, moderate and high intensity. During XCS and IC VO2max and EE were higher than during AS. At least 2½ hours of AS are necessary to reach the same EE as during one hour of XCS or IC. HR, VO2, lactate, and RPEarms were highest during XCS, whereas RPEwhole-body was similar and RPElegs lower than during AS and IC, respectively. Weight adjusted VO2 and EE were higher in men than in women while fitness level had no effect. Male, fit and young participants were able to increase their EE and VO2 values more pronounced. Both AS and XCS can be individually tailored to serve as alternatives to IC and may thus help to overcome the winter activity deficit. XCS was found to be the most effective activity for generating a high EE and VO2 while AS was the most demanding activity for the legs. Key pointsDuring cross-country skiing and indoor cycling VO2max and energy expenditure were higher than during alpine skiingApproximately 2½ hours of alpine skiing are necessary to reach the same energy expenditure of one hour of cross-country skiing or indoor cycling.Alpine skiing and cross-country skiing can be individually tailored to serve as sports alternatives in winter to activity deficit.By applying different skiing modes as parallel ski steering, carving long radii and short turn skiing, metabolic and cardiorespiratory response can be increased during alpine skiing.Male, fit and young

  11. A Comparison between Alpine Skiing, Cross-Country Skiing and Indoor Cycling on Cardiorespiratory and Metabolic Response.

    PubMed

    Stöggl, Thomas; Schwarzl, Christoph; Müller, Edith E; Nagasaki, Masaru; Stöggl, Julia; Scheiber, Peter; Schönfelder, Martin; Niebauer, Josef

    2016-03-01

    Since physical inactivity especially prevails during winter months, we set out to identify outdoor alternatives to indoor cycling (IC) by comparing the metabolic and cardiorespiratory responses during alpine skiing (AS), cross-country skiing (XCS) and IC and analyse the effects of sex, age and fitness level in this comparison. Twenty one healthy subjects performed alpine skiing (AS), cross-country skiing (XCS), and IC. Oxygen uptake (VO2), total energy expenditure (EE), heart rate (HR), lactate, blood glucose and rate of perceived exertion (RPE) were determined during three 4-min stages of low, moderate and high intensity. During XCS and IC VO2max and EE were higher than during AS. At least 2½ hours of AS are necessary to reach the same EE as during one hour of XCS or IC. HR, VO2, lactate, and RPEarms were highest during XCS, whereas RPEwhole-body was similar and RPElegs lower than during AS and IC, respectively. Weight adjusted VO2 and EE were higher in men than in women while fitness level had no effect. Male, fit and young participants were able to increase their EE and VO2 values more pronounced. Both AS and XCS can be individually tailored to serve as alternatives to IC and may thus help to overcome the winter activity deficit. XCS was found to be the most effective activity for generating a high EE and VO2 while AS was the most demanding activity for the legs. Key pointsDuring cross-country skiing and indoor cycling VO2max and energy expenditure were higher than during alpine skiingApproximately 2½ hours of alpine skiing are necessary to reach the same energy expenditure of one hour of cross-country skiing or indoor cycling.Alpine skiing and cross-country skiing can be individually tailored to serve as sports alternatives in winter to activity deficit.By applying different skiing modes as parallel ski steering, carving long radii and short turn skiing, metabolic and cardiorespiratory response can be increased during alpine skiing.Male, fit and young

  12. Fluid and electrolyte balance during a cool weather marathon.

    PubMed

    Nelson, P B; Ellis, D; Fu, F; Bloom, M D; O'Malley, J

    1989-01-01

    Changes in blood, serum, and urine parameters that are usually associated with fluid and electrolyte balance were studied in 45 volunteers who ran the 1987 Pittsburgh Marathon. There were 39 males and 6 females. The mean age was 39.3 years. Their mean fluid intake was 1650 cc and the mean finishing time was 4 hours and 1 minute. The race was run in the rain with a temperature of 46 degrees F. When the prerace and postrace values of the runners were compared, significant increases were noted in the serum sodium, potassium, blood urea nitrogen (BUN), creatinine, uric acid, creatine phosphokinase (CPK), protein, plasma renin, vasopressin, and urinary potassium. Significant decreases were found in weight, blood pressure, and urinary sodium. No significant differences were noted in serum chloride, serum glucose, and hemoglobin/hematocrit. The mean weight loss of 1.9 kg was less than weight losses reported in marathons run under warmer conditions.

  13. Terrorist bombings: foreign bodies from the Boston Marathon bombing.

    PubMed

    Brunner, John; Singh, Ajay K; Rocha, Tatiana; Havens, Joaquim; Goralnick, Eric; Sodickson, Aaron

    2015-02-01

    On April 15, 2013, 2 improvised explosive devices detonated at the 117th Boston Marathon, killing 3 people and injuring 264 others. In this article, the foreign bodies and injuries that presented at 2 of the responding level 1 trauma hospitals in Boston-Brigham and Women׳s Hospital and Massachusetts General Hospital--are reviewed with a broader discussion of blast injuries and imaging strategies. PMID:25639179

  14. ShopGirls Shine in Eco-Marathon

    ERIC Educational Resources Information Center

    Stowell, Shante

    2011-01-01

    The ShopGirls of Granite Falls (WA) High School are the first-ever all-female team to successfully design, build, and race a prototype diesel car in the Shell Eco-marathon. The team took first place in the diesel fuel-efficiency category with a vehicle that achieved 470 miles per gallon! The idea for the ShopGirls came when Vervia Gabriel, career…

  15. Achilles tendon stiffness is unchanged one hour after a marathon.

    PubMed

    Peltonen, Jussi; Cronin, Neil J; Stenroth, Lauri; Finni, Taija; Avela, Janne

    2012-10-15

    Overuse-induced injuries have been proposed as a predisposing factor for Achilles tendon (AT) ruptures. If tendons can be overloaded, their mechanical properties should change during exercise. Because there data are lacking on the effects of a single bout of long-lasting exercise on AT mechanical properties, the present study measured AT stiffness before and after a marathon. AT stiffness was determined as the slope of the force-elongation curve between 10 and 80% of maximum voluntary force. AT force-elongation characteristics were measured in an ankle dynamometer using simultaneous motion-capture-assisted ultrasonography. Oxygen consumption and ankle kinematics were also measured on a treadmill at the marathon pace. All measurements were performed before and after the marathon. AT stiffness did not change significantly from the pre-race value of 197±62 N mm(-1) (mean ± s.d.) to the post-race value of 206±59 N mm(-1) (N=12, P=0.312). Oxygen consumption increased after the race by 7±10% (P<0.05) and ankle kinematic data revealed that in nine out of 12 subjects, the marathon induced a change in their foot strike technique. The AT of the physically active individuals seems to be able to resist mechanical changes under physiological stress. We therefore suggest that natural loading, like in running, may not overstress the AT or predispose it to injury. In addition, decreased running economy, as well as altered foot strike technique, was probably attributable to muscle fatigue.

  16. Genetic-and-Epigenetic Interspecies Networks for Cross-Talk Mechanisms in Human Macrophages and Dendritic Cells during MTB Infection

    PubMed Central

    Li, Cheng-Wei; Lee, Yun-Lin; Chen, Bor-Sen

    2016-01-01

    Tuberculosis is caused by Mycobacterium tuberculosis (Mtb) infection. Mtb is one of the oldest human pathogens, and evolves mechanisms implied in human evolution. The lungs are the first organ exposed to aerosol-transmitted Mtb during gaseous exchange. Therefore, the guards of the immune system in the lungs, such as macrophages (Mϕs) and dendritic cells (DCs), are the most important defense against Mtb infection. There have been several studies discussing the functions of Mϕs and DCs during Mtb infection, but the genome-wide pathways and networks are still incomplete. Furthermore, the immune response induced by Mϕs and DCs varies. Therefore, we analyzed the cross-talk genome-wide genetic-and-epigenetic interspecies networks (GWGEINs) between Mϕs vs. Mtb and DCs vs. Mtb to determine the varying mechanisms of both the host and pathogen as it relates to Mϕs and DCs during early Mtb infection. First, we performed database mining to construct candidate cross-talk GWGEIN between human cells and Mtb. Then we constructed dynamic models to characterize the molecular mechanisms, including intraspecies gene/microRNA (miRNA) regulation networks (GRNs), intraspecies protein-protein interaction networks (PPINs), and the interspecies PPIN of the cross-talk GWGEIN. We applied a system identification method and a system order detection scheme to dynamic models to identify the real cross-talk GWGEINs using the microarray data of Mϕs, DCs and Mtb. After identifying the real cross-talk GWGEINs, the principal network projection (PNP) method was employed to construct host-pathogen core networks (HPCNs) between Mϕs vs. Mtb and DCs vs. Mtb during infection process. Thus, we investigated the underlying cross-talk mechanisms between the host and the pathogen to determine how the pathogen counteracts host defense mechanisms in Mϕs and DCs during Mtb H37Rv early infection. Based on our findings, we propose Rv1675c as a potential drug target because of its important defensive role in

  17. Did recent world record marathon runners employ optimal pacing strategies?

    PubMed

    Angus, Simon D

    2014-01-01

    We apply statistical analysis of high frequency (1 km) split data for the most recent two world-record marathon runs: Run 1 (2:03:59, 28 September 2008) and Run 2 (2:03:38, 25 September 2011). Based on studies in the endurance cycling literature, we develop two principles to approximate 'optimal' pacing in the field marathon. By utilising GPS and weather data, we test, and then de-trend, for each athlete's field response to gradient and headwind on course, recovering standardised proxies for power-based pacing traces. The resultant traces were analysed to ascertain if either runner followed optimal pacing principles; and characterise any deviations from optimality. Whereas gradient was insignificant, headwind was a significant factor in running speed variability for both runners, with Runner 2 targeting the (optimal) parallel variation principle, whilst Runner 1 did not. After adjusting for these responses, neither runner followed the (optimal) 'even' power pacing principle, with Runner 2's macro-pacing strategy fitting a sinusoidal oscillator with exponentially expanding envelope whilst Runner 1 followed a U-shaped, quadratic form. The study suggests that: (a) better pacing strategy could provide elite marathon runners with an economical pathway to significant performance improvements at world-record level; and (b) the data and analysis herein is consistent with a complex-adaptive model of power regulation.

  18. Record performances at the Boston Marathon: Biometeorological factors

    NASA Astrophysics Data System (ADS)

    Trapasso, L. Michael; Cooper, Jeffery D.

    1989-12-01

    Air temperature and relative humidity have long been suspected of affecting the performance of marathon runners. Though these factors are important in their extremes, we show that other factors are even more indicative of race performances. Performances of the top 3 finishers in the last 30 Boston Marathons were correlated with hourly meteorological data for each race day. These 90 individual performances were classified as: record breaking performances (31), average performances (35), and unusually slow performances (24). The factors that help predict record breaking and unusually slow performances are: (i) wet bulb temperature, (ii) percent sky cover, and (iii) presence or absence of a light precipitation. Record breaking performances are characterized by a wet bulb temperature of <7.8°C, and 100% sky cover. A light drizzle is also conducive to better performances. On the other hand, unusually low performances are accompanied by a wet bulb temperature of >7.8°C, and a sky cover of 50% or less. No light, precipitation was recorded on any of the unusually slow race days. A graphic analysis clearly shows these relationships to exist. In addition, a multiple regression analysis confirms the importance of these variables. The authors advise that these are reliable predictors; however, when considering marathon races held in various geographical regions and differing climatic regimes, the exact numerical thresholds used here may not apply.

  19. The modified Dmax method is reliable to predict the second ventilatory threshold in elite cross-country skiers.

    PubMed

    Fabre, Nicolas; Balestreri, Filippo; Pellegrini, Barbara; Schena, Federico

    2010-06-01

    This study was designed to evaluate, in elite cross-country skiers, the capacity of the DMAX lactate threshold method and its modified version (DMAX MOD) to accurately predict the second ventilatory threshold (VT2). Twenty-three elite cross-country skiers carried out an incremental roller-ski test on a motorized treadmill. Ventilation, heart rate (HR), and gas exchanges were continuously recorded during the test. Blood was sampled at the end of each 3-minute work stage for lactate concentration measurements. The VT2 was individually determined by visual analysis. The DMAX, DMAX MOD points also with the 4 mmol.L(-1) fixed lactate concentration value (4 mM) were determined by a computerized program. Paired t tests showed nonsignificant differences between HR at VT2 and HR at DMAX MOD, between HR at VT2 and HR at 4 mM, and between HR at DMAX MOD and HR at 4 mM. HR at DMAX was significantly lower than HR at VT2, DMAX MOD, and at 4 mM (p<0.001). HR at VT2 was strongly correlated with HR at 4 mM (r=0.93, p<0.001), HR at DMAX (r=0.97, p<0.001) and especially with HR at DMAX MOD (r=0.99, p<0.001). Bland-Altman plots showed that HR at DMAX underestimated HR at VT2 and permitted to observe that the DMAX method and particularly the DMAX MOD method had smaller limits of agreement as compared with the 4 mM method. Our results showed that the DMAX MOD lactate threshold measurement is extremely accurate to predict VT2 in elite cross-country skiers.

  20. Hard training for 5 mo increases Na(+)-K+ pump concentration in skeletal muscle of cross-country skiers.

    PubMed

    Evertsen, F; Medbø, J I; Jebens, E; Nicolaysen, K

    1997-05-01

    To study how training affects the Na(+)-K+ pump concentration, 11 male and 9 female elite junior cross-country skiers trained 12-15 h/wk at 60-70% (moderate-intensity group) or 80-90% (high-intensity group) of their maximal O2 uptake for 5 mo. Muscle biopsies taken from the vastus lateralis muscle before and after the training period were analyzed for Na(+)-K+ pump concentration by the [3H]ouabain-binding technique. Before training, the concentration was 343 +/- 11 nmol/kg wet muscle mass (mean +/- SE) for the men and 281 +/- 14 nmol/kg for the women (18% less than for the men, P = 0.003). The Na(+)-K+ pump concentration rose by 49 +/- 11 nmol/kg (16%, P < 0.001) for all subjects pooled during the training period, and there was no difference between the two training groups (P = 0.3) or the sexes (P = 0.5) in this increase. The Na(+)-K+ pump concentration correlated with the maximal O2 uptake (r = 0.6, P = 0.003), with the performance during a 20-min treadmill run (r = 0.6, P = 0.003), and to the rank of the subjects' performance as cross-country skiers (Spearman's rank correlation coefficient = 0.76, P < 0.001). These data could mean that for elite cross-country skiers the performance is related to the Na(+)-K+ pump concentration. However, other studies have shown an equally high pump concentration for far less fit subjects, suggesting that the pump concentration may not be a limiting factor.

  1. Changes in acid-base status of marathon runners during an incremental field test. Relationship to mean competitive marathon velocity.

    PubMed

    Zoladz, J A; Sargeant, A J; Emmerich, J; Stoklosa, J; Zychowski, A

    1993-01-01

    Four top-class runners who regularly performed marathon and long-distance races participated in this study. They performed a graded field test on an artificial running track within a few weeks of a competitive marathon. The test consisted of five separate bouts of running. Each period lasted 6 min with an intervening 2-min rest bout during which arterialized capillary blood samples were taken. Blood was analysed for pH, partial pressure of oxygen and carbon dioxide (PO2 and PCO2) and lactate concentration ([la-]b). The values of base excess (BE) and bicarbonate concentration ([HCO3-]) were calculated. The exercise intensity during the test was regulated by the runners themselves. The subjects were asked to perform the first bout of running at a constant heart rate fc which was 50 beats.min-1 below their own maximal fc. Every subsequent bout, each of which lasted 6 min, was performed with an increment of 10 beats.min-1 as the target fc. Thus the last, the fifth run, was planned to be performed with fc amounting to 10 beats.min-1 less than their maximal fc. The results from these runners showed that the blood pH changed very little in the bouts performed at a running speed below 100% of mean marathon velocity (nu m). However, once nu m was exceeded, there were marked changes in acid-base status. In the bouts performed at a velocity above the nu m there was a marked increase in [la-]b and a significant decrease in pH, [HCO3-], BE and pCO2. The average marathon velocity (nu m) was 18.46 (SD 0.32) km.h-1.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8375370

  2. Team-level approaches to addressing disordered eating: a qualitative study of two female collegiate cross country running teams.

    PubMed

    Kroshus, Emily; Goldman, Roberta E; Kubzansky, Laura D; Austin, S Bryn

    2014-01-01

    The objective of this study was to consider strategies used by two similarly competitive female collegiate cross country running teams to address teammate eating behaviors perceived to be unhealthy and problematic. Data were obtained through semi-structured individual interviews with team members (n = 35). Teams differed in how they addressed problematic eating behaviors: members of one team described a collaborative, positive, team-focused and direct approach, while the most commonly described strategy for the other team was to do nothing. Possible contextual and compositional reasons for between-team differences and implications for prevention and detection of disordered eating among female athletes are discussed.

  3. Comparison of Amplicor and GeneXpert MTB/RIF Tests for Diagnosis of Tuberculous Meningitis

    PubMed Central

    Patel, Vinod B.; Connolly, Cathy; Singh, Ravesh; Lenders, Laura; Matinyenya, Brian; Theron, Grant; Ndung'u, Thumbi

    2014-01-01

    There are no data about the comparative accuracy of commercially available nucleic acid amplification tests (GeneXpert MTB/RIF and Roche Amplicor) for the diagnosis of tuberculous meningitis (TBM). A total of 148 patients with suspected TBM were evaluated, and cultures served as the reference standard. The sensitivities and specificities (95% confidence interval [CI]) for the Amplicor and Xpert MTB/RIF tests were similar: 46 (31–60) versus 50 (33–67) and 99 (93–100) and 94 (84–99), respectively. PMID:25056328

  4. Revised device labeling for the Cepheid Xpert MTB/RIF assay for detecting Mycobacterium tuberculosis.

    PubMed

    2015-02-27

    The Food and Drug Administration (FDA) has cleared the Xpert MTB/RIF Assay (Cepheid; Sunnyvale, California) with an expanded intended use that includes testing of either one or two sputum specimens as an alternative to examination of serial acid-fast stained sputum smears to aid in the decision of whether continued airborne infection isolation (AII) is warranted for patients with suspected pulmonary tuberculosis. This change reflects the outcome of a recent multicenter international study demonstrating that negative Xpert MTB/RIF Assay results from either one or two sputum specimens are highly predictive of the results of two or three negative acid-fast sputum smears.

  5. Interpersonal Relationship Styles in Marathon Group Therapy: A Study with Illicit Drug Users.

    ERIC Educational Resources Information Center

    Page, Richard C.; Bridges, Ned

    1983-01-01

    Assessed how illegal drug users (N=12) related to one another during a 16-hour unstructured group marathon. Interaction analysis supported the effectiveness of the marathon group. Members and facilitators were able to relate to each other by confronting significant behaviors and receiving feedback about ways to cope with personal problems. (JAC)

  6. Marathon Group Counseling with Illicit Drug Abusers: Effects on Self-Perceptions.

    ERIC Educational Resources Information Center

    Page, Richard C.; And Others

    1987-01-01

    Compared effects, for illicit drug abusers, of five 16-hour unstructured marathon groups, and five matched, randomly selected control groups. Used semantic differential consisting of the specific adjective pairs and the evaluative scale of the concept My Real Self. Marathon group members rated some adjective pairs differently and rated the…

  7. 76 FR 12222 - Wisconsin Central, Ltd.-Abandonment Exemption-in Marathon County, WI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Surface Transportation Board Wisconsin Central, Ltd.--Abandonment Exemption--in Marathon County, WI... ] Abandonments to abandon 1.14 miles of rail line between mileposts 17.50 and 18.64, in Weston, Marathon...

  8. Direct and Nondirect Marathon Group Therapy and Internal---External Control

    ERIC Educational Resources Information Center

    Kilmann, Peter R.

    1974-01-01

    Investigates whether direct and nondirect therapist techniques within a 23-hour marathon format would differentially induce client shifts in locus of control. The no-treatment control group experienced a significant shift toward externality, while the marathon subjects did not fluctuate significantly from pretherapy to posttherapy. (Author)

  9. Marathon Groups. Facilitating the Personal Growth of Imprisoned, Black Female Heroin Abusers.

    ERIC Educational Resources Information Center

    Page, Richard C.; Kubiak, Larry

    1978-01-01

    Apparent success of the marathon groups in altering the perceptions of Black female heroin addicts toward the future, counseling, and themselves offers preliminary evidence that marathons may have potential as a counseling strategy with these clients. Future research needs to be performed to substantiate or reject these findings. (Author/PD)

  10. Aging's effects on marathon performance insights from the New York City race.

    PubMed

    Santos-Lozano, Alejandro; Angulo, Ana M; Collado, Pilar S; Sanchis-Gomar, Fabian; Pareja-Galeano, Helios; Fiuza-Luces, Carmen; Lucia, Alejandro; Garatachea, Nuria

    2015-10-01

    Most studies on aging and marathon have analyzed elite marathoners, yet the latter only represent a very small fraction of all marathon participants. In addition, analysis of variance or unpaired Student t tests are frequently used to compare mean performance times across age groups. In this report the authors propose an alternative methodology to determine the impact of aging on marathon performance in both nonelite and elite marathoners participating in the New York City Marathon. In all, 471,453 data points corresponding to 370,741 different runners over 13 race editions (1999-2011) were retrieved. Results showed that the effect of aging on marathon performance was overall comparable in both sexes, the effect of aging differed between the fastest and slowest runners in both sexes, and the magnitude of the sex differences was higher in the slowest runners than in the fastest ones. Current data suggest that the biological differences between sexes allow men to have better marathon performance across most of the human life span.

  11. Self-Actualization in a Marathon Growth Group: Do the Strong Get Stronger?

    ERIC Educational Resources Information Center

    Kimball, Ronald; Gelso, Charles J.

    This study examined the effects of a weekend marathon on the level of self-actualization of college students one and four weeks following their group experience. It also studied the relationship between ego strength and extent of change in self-actualization during a marathon. Generally, the group experience did increase self-actualization and the…

  12. Effect of Carbohydrate Ingestion on Ratings of Perceived Exertion during a Marathon.

    ERIC Educational Resources Information Center

    Utter, Alan C.; Kang, Jie; Robertson, Robert J.; Nieman, David C.; Chaloupka, Edward C.; Suminski, Richard R.; Piccinni, Cristiana R.

    2002-01-01

    Investigated the effects of carbohydrate substrate availability on ratings of perceived exertion (RPE) and hormonal regulation during a competitive marathon. Data on marathon runners randomly assigned to receive carbohydrate or placebo indicated that those who ingested carbohydrate rather than placebo beverages were able to run at a higher…

  13. Effect of a Marathon Run on Serum Lipoproteins, Creatine Kinase, and Lactate Dehydrogenase in Recreational Runners

    ERIC Educational Resources Information Center

    Kobayashi, Yoshio; Takeuchi, Toshiko; Hosoi, Teruo; Yoshizaki, Hidekiyo; Loeppky, Jack A.

    2005-01-01

    The objective of this study was to determine the effect of a marathon run on serum lipid and lipoprotein concentrations and serum muscle enzyme activities and follow their recovery after the run. These blood concentrations were measured before, immediately after, and serially after a marathon run in 15 male recreational runners. The triglyceride…

  14. The Social Determinants of Infant Mortality and Birth Outcomes in Western Developed Nations: A Cross-Country Systematic Review

    PubMed Central

    Kim, Daniel; Saada, Adrianna

    2013-01-01

    Infant mortality (IM) and birth outcomes, key population health indicators, have lifelong implications for individuals, and are unequally distributed globally. Even among western industrialized nations, striking cross-country and within-country patterns are evident. We sought to better understand these variations across and within the United States of America (USA) and Western Europe (WE), by conceptualizing a social determinants of IM/birth outcomes framework, and systematically reviewing the empirical literature on hypothesized social determinants (e.g., social policies, neighbourhood deprivation, individual socioeconomic status (SES)) and intermediary determinants (e.g., health behaviours). To date, the evidence suggests that income inequality and social policies (e.g., maternal leave policies) may help to explain cross-country variations in IM/birth outcomes. Within countries, the evidence also supports neighbourhood SES (USA, WE) and income inequality (USA) as social determinants. By contrast, within-country social cohesion/social capital has been underexplored. At the individual level, mixed associations have been found between individual SES, race/ethnicity, and selected intermediary factors (e.g., psychosocial factors) with IM/birth outcomes. Meanwhile, this review identifies several methodological gaps, including the underuse of prospective designs and the presence of residual confounding in a number of studies. Ultimately, addressing such gaps including through novel approaches to strengthen causal inference and implementing both health and non-health policies may reduce inequities in IM/birth outcomes across the western developed world. PMID:23739649

  15. Using micro-sensor data to quantify macro kinematics of classical cross-country skiing during on-snow training.

    PubMed

    Marsland, Finn; Mackintosh, Colin; Anson, Judith; Lyons, Keith; Waddington, Gordon; Chapman, Dale W

    2015-01-01

    Micro-sensors were used to quantify macro kinematics of classical cross-country skiing techniques and measure cycle rates and cycle lengths during on-snow training. Data were collected from seven national level participants skiing at two submaximal intensities while wearing a micro-sensor unit (MinimaxX™). Algorithms were developed identifying double poling (DP), diagonal striding (DS), kick-double poling (KDP), tucking (Tuck), and turning (Turn). Technique duration (T-time), cycle rates, and cycle counts were compared to video-derived data to assess system accuracy. There was good reliability between micro-sensor and video calculated cycle rates for DP, DS, and KDP, with small mean differences (Mdiff% = -0.2 ± 3.2, -1.5 ± 2.2 and -1.4 ± 6.2) and trivial to small effect sizes (ES = 0.20, 0.30 and 0.13). Very strong correlations were observed for DP, DS, and KDP for T-time (r = 0.87-0.99) and cycle count (r = 0.87-0.99), while mean values were under-reported by the micro-sensor. Incorrect Turn detection was a major factor in technique cycle misclassification. Data presented highlight the potential of automated ski technique classification in cross-country skiing research. With further refinement, this approach will allow many applied questions associated with pacing, fatigue, technique selection and power output during training and competition to be answered.

  16. Biomechanical characteristics and speed adaptation during kick double poling on roller skis in elite cross-country skiers.

    PubMed

    Göpfert, Caroline; Holmberg, Hans-Christer; Stöggl, Thomas; Müller, Erich; Lindinger, Stefan Josef

    2013-06-01

    Recent developments in cross-country ski racing should promote the use of kick double poling. This technique, however, has not been the focus in athletes' training and has barely been investigated. The aims of the present study were to develop a function-based phase definition and to analyse speed adaptation mechanisms for kick double poling in elite cross-country skiers. Joint kinematics and pole/plantar forces were recorded in 10 athletes while performing kick double poling at three submaximal roller skiing speeds. A speed increase was associated with increases in cycle length and rate, while absolute poling and leg push-off durations shortened. Despite maintained impulses of force, the peak and average pole/leg forces increased. During double poling and leg push-off, ranges of motion of elbow flexion and extension increased (p < 0.05) and were maintained for hip/knee flexion and extension. Cycle length increase was correlated to increases in average poling force (r = 0.71) and arm swing time (r = 0.88; both p < 0.05). The main speed adaptation was achieved by changes in double poling technique; however, leg push-off showed high variability among elite skiers, thus illustrating important aspects for technique training.

  17. Blood lactate level responses and comparison with submaximal running and roller skiing in cross-country skiers.

    PubMed

    Cetin, Ebru; Bilgin, Ulviye; Schurmann, Banu Can; Yarim, Imdat; Dölek, Burcu Ertas

    2013-09-01

    The purpose of this study is to examine the effect of 30-minute duration submaximal running and roller skiing exercises, which are among the most important aerobic exercise models in cross-country skiers, on lactic acid levels. The study group comprised 6 female and 4 male athletes (age: 16.87 +/- 1.87 years, body height: 168.35 +/- 5.66 cm, body weight: 56.83 +/- 7.1 kg) who competed in cross-country skiing at national and international level. All athletes participated in the study voluntarily. Measurements were performed three times as basal (1st measurement), immediately after exercise (2nd measurement) and 5 minutes after finishing exercise (3rd measurement).Statistical analysis was conducted using SPSS (version 11.5). A significant increase (P < 0.01) in lactic acid levels was found for both 30-minute submaximal exercise types; however, this effect did not differ statistically between groups. Running exercises caused greater fatigue than skiing exercises, according to percentage values, but the difference in fatigue levels between exercise types was not statistically significant.

  18. Changes in performance and poling kinetics during cross-country sprint skiing competition using the double-poling technique.

    PubMed

    Mikkola, Jussi; Laaksonen, Marko S; Holmberg, Hans-Christer; Nummela, Ari; Linnamo, Vesa

    2013-11-01

    In this study, changes in skiing performance and poling kinetics during a simulated cross-country sprint skiing competition were investigated. Twelve elite male cross-country skiers performed simulated sprint competition (4 x 1,150 m heat with 20 min recovery between the heats) using the double-poling technique. Vertical and horizontal pole forces and cycle characteristics were measured using a force plate system (20-m long) during the starting spurt, racing speed, and finishing spurt of each heat. Moreover, heat and 20-m phase velocities were determined. Vertical and horizontal pole impulses as well as mean cycle length were calculated. The velocities of heats decreased by 2.7 +/- 1.7% (p = 0.003) over the simulated competition. The 20-m spurting velocity decreased by 16 +/- 5% (p < 0.002) and poling time increased by 18 +/- 9% (p < 0.003) in spurt phases within heats. Vertical and horizontal poling impulses did not change significantly during the simulation; however, the mean forces decreased (p < 0.039) (vertical by 24 +/- 11% and horizontal by 20 +/- 10%) within heats but not between the heats. Decreased heat velocities over the simulated sprint and spurting velocities within heats indicated fatigue among the skiers. Fatigue was also manifested by decreased pole force production and increased poling time.

  19. The social determinants of infant mortality and birth outcomes in Western developed nations: a cross-country systematic review.

    PubMed

    Kim, Daniel; Saada, Adrianna

    2013-06-01

    Infant mortality (IM) and birth outcomes, key population health indicators, have lifelong implications for individuals, and are unequally distributed globally. Even among western industrialized nations, striking cross-country and within-country patterns are evident. We sought to better understand these variations across and within the United States of America (USA) and Western Europe (WE), by conceptualizing a social determinants of IM/birth outcomes framework, and systematically reviewing the empirical literature on hypothesized social determinants (e.g., social policies, neighbourhood deprivation, individual socioeconomic status (SES)) and intermediary determinants (e.g., health behaviours). To date, the evidence suggests that income inequality and social policies (e.g., maternal leave policies) may help to explain cross-country variations in IM/birth outcomes. Within countries, the evidence also supports neighbourhood SES (USA, WE) and income inequality (USA) as social determinants. By contrast, within-country social cohesion/social capital has been underexplored. At the individual level, mixed associations have been found between individual SES, race/ethnicity, and selected intermediary factors (e.g., psychosocial factors) with IM/birth outcomes. Meanwhile, this review identifies several methodological gaps, including the underuse of prospective designs and the presence of residual confounding in a number of studies. Ultimately, addressing such gaps including through novel approaches to strengthen causal inference and implementing both health and non-health policies may reduce inequities in IM/birth outcomes across the western developed world.

  20. A Comparison of the Xpert MTB/RIF and MTBDRplus 2 Assays in Georgia

    PubMed Central

    Bablishvili, N; Tukvadze, N; Avaliani, Z.; Blumberg, HM; Kempker, RR

    2015-01-01

    Few studies have directly compared the performance of rapid molecular diagnostic tests for tuberculosis (TB). We found that commercially available molecular diagnostic tests, the Xpert MTB/RIF and GenoType MTBDRplus, both provided timely and accurate results as compared to conventional phenotypic tests in the detection of TB and rifampicin resistance. PMID:25946358

  1. Comparison of heart rate deflection and ventilatory threshold during a field cross-country roller-skiing test.

    PubMed

    Fabre, Nicolas; Passelergue, Philippe; Bouvard, Marc; Perrey, Stéphane

    2008-11-01

    This study was to assess whether the point of deflection from linearity of heart rate (HRd) could be an accurate predictor of ventilatory threshold (VT2) during a specific cross-country roller-skiing (RS) test. Ten well-trained cross-country skiers performed a maximal and incremental RS test in the field and a standardized maximal and incremental treadmill running (TR) test in the laboratory. Values of oxygen uptake (VO2) and heart rate (HR) were continuously recorded during all exercises by a portable breath-by-breath gas exchange measurement system and a wireless Polar monitoring system, respectively. The VT2 and HRd points were individually determined by visual analysis during RS. Maximal VO2 (VO2 max) and HR were higher (p < 0.05) during TR (67.1 +/- 7.3 ml x min(-1) x kg(-1) and 196.0 +/- 14.1 bpm, respectively) compared with RS (64.2 +/- 7.3 ml x min(-1) x kg(-1) and 191.5 +/- 13.1 bpm, respectively). However, a high correlation (r = 0.94, p < 0.01) between TR and VO2 max was observed. Paired t-tests showed no significant differences in HR (183.6 +/- 15.1 vs. 185.2 +/- 13.9 bpm) and VO2 (55.5 +/- 7.1 vs. 55.8 +/- 6.1 ml x min(-1) x kg(-1)) at intensities corresponding to HRd and VT2 during the RS test, respectively; Pearson product-moment correlation coefficients demonstrated significant relationships for HR at the HRd and VT2 points (r = 0.99, p < 0.001) as well as for VO2 (r = 0.95, p < 0.001). Our results indicate that the specific incremental RS test is effective in eliciting HRd in the field for all skiers and is an accurate predictor of VT2. These findings give very interesting practical applications to cross-country coaches and skiers to evaluate and control specific aerobic training loads.

  2. Neuromuscular consequences of an extreme mountain ultra-marathon.

    PubMed

    Millet, Guillaume Y; Tomazin, Katja; Verges, Samuel; Vincent, Christopher; Bonnefoy, Régis; Boisson, Renée-Claude; Gergelé, Laurent; Féasson, Léonard; Martin, Vincent

    2011-01-01

    We investigated the physiological consequences of one of the most extreme exercises realized by humans in race conditions: a 166-km mountain ultra-marathon (MUM) with 9500 m of positive and negative elevation change. For this purpose, (i) the fatigue induced by the MUM and (ii) the recovery processes over two weeks were assessed. Evaluation of neuromuscular function (NMF) and blood markers of muscle damage and inflammation were performed before and immediately following (n = 22), and 2, 5, 9 and 16 days after the MUM (n = 11) in experienced ultra-marathon runners. Large maximal voluntary contraction decreases occurred after MUM (-35% [95% CI: -28 to -42%] and -39% [95% CI: -32 to -46%] for KE and PF, respectively), with alteration of maximal voluntary activation, mainly for KE (-19% [95% CI: -7 to -32%]). Significant modifications in markers of muscle damage and inflammation were observed after the MUM as suggested by the large changes in creatine kinase (from 144 ± 94 to 13,633 ± 12,626 UI L(-1)), myoglobin (from 32 ± 22 to 1,432 ± 1,209 µg L(-1)), and C-Reactive Protein (from <2.0 to 37.7 ± 26.5 mg L(-1)). Moderate to large reductions in maximal compound muscle action potential amplitude, high-frequency doublet force, and low frequency fatigue (index of excitation-contraction coupling alteration) were also observed for both muscle groups. Sixteen days after MUM, NMF had returned to initial values, with most of the recovery process occurring within 9 days of the race. These findings suggest that the large alterations in NMF after an ultra-marathon race are multi-factorial, including failure of excitation-contraction coupling, which has never been described after prolonged running. It is also concluded that as early as two weeks after such an extreme running exercise, maximal force capacities have returned to baseline.

  3. Completing the Results of the 2013 Boston Marathon

    PubMed Central

    Hammerling, Dorit; Cefalu, Matthew; Cisewski, Jessi; Dominici, Francesca; Parmigiani, Giovanni; Paulson, Charles; Smith, Richard L.

    2014-01-01

    The 2013 Boston marathon was disrupted by two bombs placed near the finish line. The bombs resulted in three deaths and several hundred injuries. Of lesser concern, in the immediate aftermath, was the fact that nearly 6,000 runners failed to finish the race. We were approached by the marathon's organizers, the Boston Athletic Association (BAA), and asked to recommend a procedure for projecting finish times for the runners who could not complete the race. With assistance from the BAA, we created a dataset consisting of all the runners in the 2013 race who reached the halfway point but failed to finish, as well as all runners from the 2010 and 2011 Boston marathons. The data consist of split times from each of the 5 km sections of the course, as well as the final 2.2 km (from 40 km to the finish). The statistical objective is to predict the missing split times for the runners who failed to finish in 2013. We set this problem in the context of the matrix completion problem, examples of which include imputing missing data in DNA microarray experiments, and the Netflix prize problem. We propose five prediction methods and create a validation dataset to measure their performance by mean squared error and other measures. The best method used local regression based on a K-nearest-neighbors algorithm (KNN method), though several other methods produced results of similar quality. We show how the results were used to create projected times for the 2013 runners and discuss potential for future application of the same methodology. We present the whole project as an example of reproducible research, in that we are able to make the full data and all the algorithms we have used publicly available, which may facilitate future research extending the methods or proposing completely different approaches. PMID:24727904

  4. Completing the results of the 2013 Boston marathon.

    PubMed

    Hammerling, Dorit; Cefalu, Matthew; Cisewski, Jessi; Dominici, Francesca; Parmigiani, Giovanni; Paulson, Charles; Smith, Richard L

    2014-01-01

    The 2013 Boston marathon was disrupted by two bombs placed near the finish line. The bombs resulted in three deaths and several hundred injuries. Of lesser concern, in the immediate aftermath, was the fact that nearly 6,000 runners failed to finish the race. We were approached by the marathon's organizers, the Boston Athletic Association (BAA), and asked to recommend a procedure for projecting finish times for the runners who could not complete the race. With assistance from the BAA, we created a dataset consisting of all the runners in the 2013 race who reached the halfway point but failed to finish, as well as all runners from the 2010 and 2011 Boston marathons. The data consist of split times from each of the 5 km sections of the course, as well as the final 2.2 km (from 40 km to the finish). The statistical objective is to predict the missing split times for the runners who failed to finish in 2013. We set this problem in the context of the matrix completion problem, examples of which include imputing missing data in DNA microarray experiments, and the Netflix prize problem. We propose five prediction methods and create a validation dataset to measure their performance by mean squared error and other measures. The best method used local regression based on a K-nearest-neighbors algorithm (KNN method), though several other methods produced results of similar quality. We show how the results were used to create projected times for the 2013 runners and discuss potential for future application of the same methodology. We present the whole project as an example of reproducible research, in that we are able to make the full data and all the algorithms we have used publicly available, which may facilitate future research extending the methods or proposing completely different approaches.

  5. [Tomodensitometry measurements of proximal tibia and acceleration in marathon athletes].

    PubMed

    Gremion, Gérald; Cordey, Jacques; Leyvraz, Pierre-François; Rizzoli, René; Crettenand, Antoinette; Gobelet, Charles; Dériaz, Olivier; Crettenand, Andre

    2004-02-01

    We evaluated bone adaptation of the tibia to mechanical stresses in male marathon runners and in sedentary controls in function of the ground impact measured by accelerometry and of the bone mineral density assessed by peripheral quantitative computed tomography (QCT). Sixty-three subjects (51 runners and 12 controls) were enrolled. All had measurements of bone mineral density of the proximal tibia and of acceleration at the same site during a jogging at 9 km/hour. The results show a significant higher cortical BMD in runners with the higher value of late accelerations (at 50 ms after the contact with the ground). The late acceleration might be related to muscle contraction.

  6. Acute renal failure in the "Comrades Marathon" runners.

    PubMed

    Seedat, Y K; Aboo, N; Naicker, S; Parsoo, I

    This study investigated the clinical and biochemical features of acute renal failure in marathon runners. Over a period of 18 years (1969-1986), 19 patients were admitted to the renal unit. The histories and biochemical data of 4 patients seen in 1986 are described. The pathophysiology of acute renal failure is multifactorial and is the combined effect of rhabdomyolysis, dehydration, hypotension, nonsteroidal anti-inflammatory drugs, and hyperuricaemia. Efforts to correct dehydration have resulted in a decrease in the incidence of acute renal failure. The use of nonsteroidal anti-inflammatory drugs is to be deprecated and efforts should be made to publicize this harmful effect. PMID:2485484

  7. Cardiac Output and Performance during a Marathon Race in Middle-Aged Recreational Runners

    PubMed Central

    Billat, Véronique L.; Petot, Hélène; Landrain, Morgan; Meilland, Renaud; Koralsztein, Jean Pierre; Mille-Hamard, Laurence

    2012-01-01

    Purpose. Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV) and cardiac output (CO) to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance) and/or CO, per meter (i.e., cardiac cost). Methods. We measured the SV, heart rate (HR), CO, and running speed of 14 recreational runners in an incremental, maximal laboratory test and then during a real marathon race (mean performance: 3 hr 30 min ± 45 min). Results. Our data revealed that HR, SV and CO were all in a high but submaximal steady state during the marathon (87.0 ± 1.6%, 77.2 ± 2.6%, and 68.7 ± 2.8% of maximal values, respectively). Marathon performance was inversely correlated with an upward drift in the CO/speed ratio (mL of CO × m−1) (r = −0.65, P < 0.01) and positively correlated with the runner's ability to complete the race at a high percentage of the speed at maximal SV (r = 0.83, P < 0.0002). Conclusion. Our results showed that marathon performance is inversely correlated with cardiac cost and positively correlated with cardiac endurance. The CO response could be a benchmark for race performance in recreational marathon runners. PMID:22645458

  8. A limit-cycle model of leg movements in cross-country skiing and its adjustments with fatigue.

    PubMed

    Cignetti, F; Schena, F; Mottet, D; Rouard, A

    2010-08-01

    Using dynamical modeling tools, the aim of the study was to establish a minimal model reproducing leg movements in cross-country skiing, and to evaluate the eventual adjustments of this model with fatigue. The participants (N=8) skied on a treadmill at 90% of their maximal oxygen consumption, up to exhaustion, using the diagonal stride technique. Qualitative analysis of leg kinematics portrayed in phase planes, Hooke planes, and velocity profiles suggested the inclusion in the model of a linear stiffness and an asymmetric van der Pol-type nonlinear damping. Quantitative analysis revealed that this model reproduced the observed kinematics patterns of the leg with adequacy, accounting for 87% of the variance. A rising influence of the stiffness term and a dropping influence of the damping terms were also evidenced with fatigue. The meaning of these changes was discussed in the framework of motor control.

  9. Optimal [Formula: see text] ratio for predicting 15 km performance among elite male cross-country skiers.

    PubMed

    Carlsson, Tomas; Carlsson, Magnus; Hammarström, Daniel; Rønnestad, Bent R; Malm, Christer B; Tonkonogi, Michail

    2015-01-01

    The aim of this study was 1) to validate the 0.5 body-mass exponent for maximal. oxygen uptake [Formula: see text] as the optimal predictor of performance in a 15 km classical-technique skiing competition among elite male cross-country skiers and 2) to evaluate the influence of distance covered on the body-mass exponent for [Formula: see text] among elite male skiers. Twenty-four elite male skiers (age: 21.4±3.3 years [mean ± standard deviation]) completed an incremental treadmill roller-skiing test to determine their [Formula: see text]. Performance data were collected from a 15 km classical-technique cross-country skiing competition performed on a 5 km course. Power-function modeling (ie, an allometric scaling approach) was used to establish the optimal body-mass exponent for [Formula: see text] to predict the skiing performance. The optimal power-function models were found to be [Formula: see text] and [Formula: see text], which explained 69% and 81% of the variance in skiing speed, respectively. All the variables contributed to the models. Based on the validation results, it may be recommended that [Formula: see text] divided by the square root of body mass (mL · min(-1) · kg(-0.5)) should be used when elite male skiers' performance capability in 15 km classical-technique races is evaluated. Moreover, the body-mass exponent for [Formula: see text] was demonstrated to be influenced by the distance covered, indicating that heavier skiers have a more pronounced positive pacing profile (ie, race speed gradually decreasing throughout the race) compared to that of lighter skiers.

  10. Effect of cold conditions on double poling sprint performance of well-trained male cross-country skiers.

    PubMed

    Wiggen, Øystein N; Waagaard, Silje H; Heidelberg, Cecilie T; Oksa, Juha

    2013-12-01

    This study compared the effects of cold (-14° C) and moderate environments (6° C) on double poling (DP) sprint performance. Wearing modern cross-country ski racing suits, 14 highly trained male cross-country skiers performed a test protocol on a DP ergometer, consisting of a standardized warm-up followed by a 30-second maximal sprint (DP30s) and a 2-minute maximal sprint (DP2min), and after an 8-minute recovery period, another DP30s and DP2min were performed. Finally, the participants performed an incremental DP test to exhaustion. We observed no difference between rectal temperature in cold and moderate conditions. Mean skin temperature (Tskin) was lower in the cold condition; the lowest values being 20.3° C at -14° C and 27.0° C at 6° C. Power output decreased between the first and the second DP30s under both conditions, but the reduction was 4.9% (p < 0.05) greater in the cold condition. Power output decreased by 4.8% (p < 0.05) between the first and second DP2min at -14° C, but we found no difference at 6° C. In the incremental test to exhaustion, there was a 7.2% (p < 0.05) reduction in peak power output and a 7.8% (p < 0.05) lower peak oxygen consumption at -14° C. In conclusion, this study demonstrated that DP sprint performance was lower at -14° C than at 6° C. Tskin and body temperature were lower at -14° C. This may indicate cooling of superficial musculature and may explain the reduced DP sprint performance observed in our study.

  11. How do elite cross-country skiers adapt to different double poling frequencies at low to high speeds?

    PubMed

    Lindinger, Stefan Josef; Holmberg, Hans-Christer

    2011-06-01

    The purpose of the study was to examine the biomechanical-physiological effects of different frequencies using the double poling technique in cross-country skiing. Nine elite skiers roller-skied using poling frequencies of 40, 60 and 80 cycles·min(-1) (Pf(40,) Pf(60), Pf(80)) at submaximal treadmill speeds (12, 18, 24 km·h(-1)). Cycle characteristics, pole forces, joint angles and physiological responses were measured. Comparing Pf(40) versus Pf(60) versus Pf(80) (all variables different at P < 0.05), absolute poling time decreased by up to 46%, as did absolute and relative (% cycle time) recovery times, at almost all speeds. Peak force, impulse of force and time to peak force decreased, whereas impact force increased with frequency at almost all speeds. Elbow ranges of motion and angular velocities, hip and knee angle maxima and flexion/extension ranges of motion per cycle decreased, whereas hip and knee angle minima, ranges of motion per minute and angular extension velocities during recovery phase all increased with frequency at nearly all speeds. Oxygen uptake and heart rate increased up to 13% (Pf(40-60) versus Pf(80)) at all speeds. Pulmonary ventilation increased most distinctly at the highest speed. Blood lactate was lowest at Pf(60) and highest at Pf(80) (J-shape curve) at 24 km·h(-1). Gross efficiency decreased with higher frequency at all speeds. These results demonstrate different biomechanical and physiological demands at different frequencies with the beneficial effects of lower poling frequencies at submaximal speeds. For training purposes, we suggest that cross-country skiers would benefit by training with different poling frequencies to vary their training load.

  12. Prevalence of Hyponatremia, Renal Dysfunction, and Other Electrolyte Abnormalities Among Runners Before and After Completing a Marathon or Half Marathon

    PubMed Central

    Mohseni, Michael; Silvers, Scott; McNeil, Rebecca; Diehl, Nancy; Vadeboncoeur, Tyler; Taylor, Walt; Shapiro, Shane; Roth, Jennifer; Mahoney, Sherry

    2011-01-01

    Background: Prior reports on metabolic derangements observed in distance running frequently have small sample sizes, lack prerace laboratory measures, and report sodium as the sole measure. Hypothesis: Metabolic abnormalities—hyponatremia, hypokalemia, renal dysfunction, hemoconcentration—are frequent after completing a full or half marathon. Clinically significant changes occur in these laboratory values after race completion. Study Design: Observational, cross-sectional study. Methods: Consenting marathon and half marathon racers completed a survey as well as finger stick blood sampling on race day of the National Marathon to Fight Breast Cancer (Jacksonville, Florida, February 2008). Parallel blood measures were obtained before and after race completion (prerace, n = 161; postrace, n = 195). Results: The prevalence of prerace and postrace hyponatremia was 8 of 161 (5.0%) and 16 of 195 (8.2%), respectively. Hypokalemia was not present prerace but was present in 1 runner postrace (1 of 195). Renal dysfunction occurred prerace in 14 of 161 (8.7%) and postrace in 83 of 195 (42.6%). Among those with postrace renal dysfunction, 45.8% (38 of 83) were classified as moderate or severe. Hemoconcentration was present in 2 of 161 (1.2%) prerace and 6 of 195 (3.1%) postrace. The mean changes in laboratory values were (postrace minus prerace): sodium, 1.6 mmol/L; potassium, −0.2 mmol/L; blood urea nitrogen, 2.8 mg/dL; creatinine, 0.2 mg/dL; and hemoglobin, 0.3 g/dL for 149 pairs (except blood urea nitrogen, n = 147 pairs). Changes were significant for all comparisons (P < 0.01) except potassium (P = 0.08) and hemoglobin (P = 0.01). Conclusions: Metabolic abnormalities are common among endurance racers, and they may be present prerace, including hyponatremia. The clinical significance of these findings is unknown. Clinical relevance: It is unclear which runners are at risk for developing clinically important metabolic derangements. Participating in prolonged endurance

  13. Male and female Ethiopian and Kenyan runners are the fastest and the youngest in both half and full marathon.

    PubMed

    Knechtle, Beat; Nikolaidis, Pantelis T; Onywera, Vincent O; Zingg, Matthias A; Rosemann, Thomas; Rüst, Christoph A

    2016-01-01

    In major marathon races such as the 'World Marathon Majors', female and male East African runners particularly from Ethiopia and Kenya are the fastest. However, whether this trend appears for female and male Ethiopians and Kenyans at recreational level runners (i.e. races at national level) and in shorter road races (e.g. in half-marathon races) has not been studied yet. Thus, the aim of the present study was to examine differences in the performance and the age of female and male runners from East Africa (i.e. Ethiopians and Kenyans) between half- and full marathons. Data from 508,108 athletes (125,894 female and 328,430 male half-marathoners and 10,205 female and 43,489 male marathoners) originating from 126 countries and competing between 1999 and 2014 in all road-based half-marathons and marathons held in one country (Switzerland) were analysed using Chi square (χ(2)) tests, mixed-effects regression analyses and one-way analyses of variance. In half-marathons, 48 women (0.038 %) and 63 men (0.019 %) were from Ethiopia and 80 women (0.063 %) and 134 men (0.040 %) from Kenya. In marathons, three women (0.029 %) and 15 men (0.034 %) were from Ethiopia and two women (0.019 %) and 33 men (0.075 %) from Kenya. There was no statistically significant association between the nationality of East Africans and the format of a race. In both women and men, the fastest race times in half-marathons and marathons were achieved by East African runners (p < 0.001). Ethiopian and Kenyan runners were the youngest in both sexes and formats of race (p < 0.001). In summary, women and men from Ethiopia and Kenya, despite they accounted for <0.1 % in half-marathons and marathons, achieved the fastest race times and were the youngest in both half-marathons and marathons. These findings confirmed in the case of half-marathon the trend previously observed in marathon races for a better performance and a younger age in East African runners from Ethiopia and Kenya. PMID

  14. History and prevalence of doping in the marathon.

    PubMed

    Hoberman, John

    2007-01-01

    Anti-doping activism represents the mainstream of the current anti-doping campaign and includes both an ethical critique of doping and a call for the sharpening of sanctions. At the same time, evolving evidence indicates that systemic doping in some sports has existed on a larger scale than most observers thought possible. Doping has historical roots in the physiological demands of extreme endurance sport. The Victorian philosophy of sportsmanship and fair competition that emphasises the importance of a capacity for self-restraint and expresses a code of honour, once associated with the gentleman ideal, is the basis of the current anti-doping movement. The problem with this focus is the assumption that there is a contradiction between high-performance endurance sports and doping practices that is not found in the historical record. Compared with the hundreds of professional cyclists who have tested positive for banned substances in recent decades, the list of offenders in the marathon is very short. At the same time, the low number of positive tests is an inadequate basis for estimating the extent of doping among elite marathon runners today. A better understanding of this phenomenon would require something like anthropological fieldwork conducted in this subculture.

  15. Impact of Environmental Parameters on Marathon Running Performance

    PubMed Central

    El Helou, Nour; Tafflet, Muriel; Berthelot, Geoffroy; Tolaini, Julien; Marc, Andy; Guillaume, Marion; Hausswirth, Christophe; Toussaint, Jean-François

    2012-01-01

    Purpose The objectives of this study were to describe the distribution of all runners' performances in the largest marathons worldwide and to determine which environmental parameters have the maximal impact. Methods We analysed the results of six European (Paris, London, Berlin) and American (Boston, Chicago, New York) marathon races from 2001 to 2010 through 1,791,972 participants' performances (all finishers per year and race). Four environmental factors were gathered for each of the 60 races: temperature (°C), humidity (%), dew point (°C), and the atmospheric pressure at sea level (hPA); as well as the concentrations of four atmospheric pollutants: NO2 – SO2 – O3 and PM10 (μg.m−3). Results All performances per year and race are normally distributed with distribution parameters (mean and standard deviation) that differ according to environmental factors. Air temperature and performance are significantly correlated through a quadratic model. The optimal temperatures for maximal mean speed of all runners vary depending on the performance level. When temperature increases above these optima, running speed decreases and withdrawal rates increase. Ozone also impacts performance but its effect might be linked to temperature. The other environmental parameters do not have any significant impact. Conclusions The large amount of data analyzed and the model developed in this study highlight the major influence of air temperature above all other climatic parameter on human running capacity and adaptation to race conditions. PMID:22649525

  16. Shape-based virtual screening, docking, and molecular dynamics simulations to identify Mtb-ASADH inhibitors.

    PubMed

    Kumar, Rajender; Garg, Prabha; Bharatam, P V

    2015-01-01

    Aspartate β-semialdehyde dehydrogenase (ASADH) is a key enzyme for the biosynthesis of essential amino acids and several important metabolites in microbes. Inhibition of ASADH enzyme is a promising drug target strategy against Mycobacterium tuberculosis (Mtb). In this work, in silico approach was used to identify potent inhibitors of Mtb-ASADH. Aspartyl β-difluorophosphonate (β-AFP), a known lead compound, was used to understand the molecular recognition interactions (using molecular docking and molecular dynamics analysis). This analysis helped in validating the computational protocol and established the participation of Arg99, Glu224, Cys130, Arg249, and His256 amino acids as the key amino acids in stabilizing ligand-enzyme interactions for effective binding, an essential feature is H-bonding interactions with the two arginyl residues at the two ends of the ligand. Best binding conformation of β-AFP was selected as a template for shape-based virtual screening (ZINC and NCI databases) to identify compounds that competitively inhibit the Mtb-ASADH. The top rank hits were further subjected to ADME and toxicity filters. Final filter was based on molecular docking analysis. Each screened molecule carries the characteristics of the highly electronegative groups on both sides separated by an average distance of 6 Å. Finally, the best predicted 20 compounds exhibited minimum three H-bonding interactions with Arg99 and Arg249. These identified hits can be further used for designing the more potent inhibitors against ASADH family. MD simulations were also performed on two selected compounds (NSC4862 and ZINC02534243) for further validation. During the MD simulations, both compounds showed same H-bonding interactions and remained bound to key active residues of Mtb-ASADH.

  17. Paraspinal abscess secondary to tuberculous spondylitis diagnosed by Xpert MTB/RIF assay in rural Tanzania.

    PubMed

    Hella, Jerry Joseph; Hiza, Hellen Charles; Mfinanga, Elirehema; Reither, Klaus

    2013-01-01

    A 31-year-old HIV-negative man presented to our clinic with a 6-month history of back pain and a swelling at the back. Radiological studies revealed lumbar vertebral destruction. Ultrasound of the mass showed a septated cystic mass with turbid fluid. Diagnostic aspiration revealed thick pus and smear microscopy detected acid-fast bacilli. Xpert MTB/RIF assay detected Mycobacterium tuberculosis with no rifampicin resistance.

  18. The role of Xpert MTB/RIF in diagnosing pulmonary tuberculosis in post-mortem tissues

    PubMed Central

    García-Basteiro, Alberto L.; Ismail, Mamudo R.; Carrilho, Carla; Ussene, Esperança; Castillo, Paola; Chitsungo, Dércio; Rodríguez, Cristina; Lovane, Lucília; Vergara, Andrea; López-Varela, Elisa; Mandomando, Inacio; Lorenzoni, Cesaltina; Ordi, Jaume; Menéndez, Clara; Bassat, Quique; Martínez, Miguel J.

    2016-01-01

    The extent to which the Xpert MTB/RIF (Gene Xpert) contributes to tuberculosis (TB) diagnosis in samples other than sputum and cerebrospinal fluid remains uncertain. We aimed to assess the role of Xpert MTB/RIF for detecting M. tuberculosis in post-mortem tissues. We conducted a study among 30 complete diagnostic autopsies (CDA) performed at the Maputo Central Hospital (Mozambique). Lung tissues were screened for TB in all cases. In addition other tissues were tested when compatible lesions were identified in the histological exam. We used in-house real time PCR and LAMP assays to confirm the presence of M. tuberculosis DNA. The diagnosis of tuberculosis at death was established based on microbiological and histopathological results. Eight out of 30 cases (26.7%) were diagnosed of tuberculosis. Xpert had a sensitivity to detect TB in lung tissue of 87.5% (95% CI 47.3–99.7) and a specificity of 95.7% (95% CI: 78.1–99.9). In-house DNA amplification methods and Xpert showed 93.6% concordance for lung tissue and 100% concordance for brain and liver tissues. The final cause of death was attributable to tuberculosis in four cases. Xpert MTB/RIF may represent a valuable, easy-to perform technique for post-mortem TB diagnosis. PMID:26860394

  19. Defined tuberculosis vaccine, Mtb72F/AS02A, evidence of protection in cynomolgus monkeys

    PubMed Central

    Reed, Steven G.; Coler, Rhea N.; Dalemans, Wilfried; Tan, Esterlina V.; DeLa Cruz, Eduardo C.; Basaraba, Randall J.; Orme, Ian M.; Skeiky, Yasir A. W.; Alderson, Mark R.; Cowgill, Karen D.; Prieels, Jean-Paul; Abalos, Rodolfo M.; Dubois, Marie-Claude; Cohen, Joe; Mettens, Pascal; Lobet, Yves

    2009-01-01

    The development of a vaccine for tuberculosis requires a combination of antigens and adjuvants capable of inducing appropriate and long-lasting T cell immunity. We evaluated Mtb72F formulated in AS02A in the cynomolgus monkey model. The vaccine was immunogenic and caused no adverse reactions. When monkeys were immunized with bacillus Calmette–Guérin (BCG) and then boosted with Mtb72F in AS02A, protection superior to that afforded by using BCG alone was achieved, as measured by clinical parameters, pathology, and survival. We observed long-term survival and evidence of reversal of disease progression in monkeys immunized with the prime-boost regimen. Antigen-specific responses from protected monkeys receiving BCG and Mtb72F/AS02A had a distinctive cytokine profile characterized by an increased ratio between 3 Th1 cytokines, IFN-γ, TNF, and IL-2 and an innate cytokine, IL-6. To our knowledge, this is an initial report of a vaccine capable of inducing long-term protection against tuberculosis in a nonhuman primate model, as determined by protection against severe disease and death, and by other clinical and histopathological parameters. PMID:19188599

  20. Seasonal variations in VO2max, O2-cost, O2-deficit, and performance in elite cross-country skiers.

    PubMed

    Losnegard, Thomas; Myklebust, Håvard; Spencer, Matt; Hallén, Jostein

    2013-07-01

    Long-term effects of training are important information for athletes, coaches, and scientists when associating changes in physiological indices with changes in performance. Therefore, this study monitored changes in aerobic and anaerobic capacities and performance in a group of elite cross-country skiers during a full sport season. Thirteen men (age, 23 ± 2 years; height, 182 ± 6 cm; body mass, 76 ± 8 kg; V2 roller ski skating VO2max, 79.3 ± 4.4 ml·kg·min or 6.0 ± 0.5 L·min) were tested during the early, middle, and late preparation phase: June (T1), August (T2), and October (T3); during the competition phase: January/February (T4); and after early precompetition phase: June (T5). O2-cost during submaximal efforts, V[Combining Dot Above]O2peak, accumulated oxygen deficit (ΣO2-deficit), and performance during a 1,000-m test were determined in the V2 ski skating technique on a roller ski treadmill. Subjects performed their training on an individual basis, and detailed training logs were categorized into different intensity zones and exercise modes. Total training volume was highest during the summer months (early preseason) and decreased toward and through the winter season, whereas the volume of high-intensity training increased (all p < 0.05). There was a significant main effect among testing sessions for 1,000 m time, O2-cost, and ΣO2-deficit (Cohen's d effect size; ES = 0.63-1.37, moderate to large, all p < 0.05). In general, the changes occurred between T1 and T3 with minor changes in the competitive season (T3 to T4). No significant changes were found in V[Combining Dot Above]O2peak across the year (ES = 0.17, trivial). In conclusion, the training performed by elite cross-country skiers induced no significant changes in V[Combining Dot Above]O2peak but improved performance, O2-cost, and ΣO2-deficit.

  1. Body Composition and Dietary Intake of Elite Cross-country Skiers Members of the Greek National Team

    PubMed Central

    Papadopoulou, Sousana K.; Gouvianaki, Anna; Grammatikopoulou, Maria G.; Maraki, Zoi; Pagkalos, Ioannis G.; Malliaropoulos, Nikolaos; Hassapidou, Maria N.; Maffulli, Nicola

    2012-01-01

    Purpose To assess the anthropometric characteristics and dietary intake of the Greek national cross-country skiing team. Methods Thirty-three athletes (10 females aged 20 ± 5 years; 23 males aged 20 ± 6 years old) participated in the study. All athletes were members of the Greek national ski team, and they had been selected to take part in the Winter Olympics, World Ski Championships, European Ski Championships or other international events, according to their performance. Body composition was estimated by bioelectrical impedance (BIA) and skinfold thickness. The athletes recorded their physical activity and dietary intake for 3 training days, and on a competition day. Results The female skiers had 14.2±1.9% body fat, the men 11.0±1.5% body fat. Female athletes consumed a diet of 1988±319 Kcal during training days and 2011±330 Kcal during competition days. Male athletes consumed 2255±790 Kcal and 2125±639 Kcal respectively. These values are below those recommended for highly active people. During the training period, carbohydrate, fat and protein contributed to 44.5±7.1%, 39.2±5.3% and 16.1±3.7% of the total energy intake (EI) respectively for the males, and to 52.8±5.6%, 33.0±3.7% and 14.3±2.5% of the EI of the women. Between training and competition days, men demonstrated an increased carbohydrate and reduced fat consumption when competing (P<0.001 for both). Women, on the other hand, consumed more carbohydrate and less protein during competition days (P<0.05 for both). Protein intake was within the recommended range for both males and females, but fat exceeded the recommended values and was consumed at the expense of carbohydrate. Vitamins B12, D, E and K, biotin, folate, Ca, Mg, K, I were inadequately consumed (below the RDA) by both women and men, while the women also exhibited inadequate intakes of iron and the men of manganese. Conclusions The inadequate energy and nutrient intake in the Greek national cross-country ski team could put the

  2. Alveolar-Membrane Diffusing Capacity Limits Performance in Boston Marathon Qualifiers

    PubMed Central

    Lavin, Kaleen M.; Straub, Allison M.; Uhranowsky, Kathleen A.; Smoliga, James M.; Zavorsky, Gerald S.

    2012-01-01

    Purpose (1) to examine the relation between pulmonary diffusing capacity and marathon finishing time, and (2), to evaluate the accuracy of pulmonary diffusing capacity for nitric oxide (DLNO) in predicting marathon finishing time relative to that of pulmonary diffusing capacity for carbon monoxide (DLCO). Methods 28 runners [18 males, age = 37 (SD 9) years, body mass = 70 (13) kg, height = 173 (9) cm, percent body fat = 17 (7) %] completed a test battery consisting of measurement of DLNO and DLCO at rest, and a graded exercise test to determine running economy and aerobic capacity prior to the 2011 Steamtown Marathon (Scranton, PA). One to three weeks later, all runners completed the marathon (range: 2∶22:38 to 4∶48:55). Linear regressions determined the relation between finishing time and a variety of anthropometric characteristics, resting lung function variables, and exercise parameters. Results In runners meeting Boston Marathon qualification standards, 74% of the variance in marathon finishing time was accounted for by differences in DLNO relative to body surface area (BSA) (SEE = 11.8 min, p<0.01); however, the relation between DLNO or DLCO to finishing time was non-significant in the non-qualifiers (p = 0.14 to 0.46). Whereas both DLCO and DLNO were predictive of finishing time for all finishers, DLNO showed a stronger relation (r2 = 0.30, SEE = 33.4 min, p<0.01) compared to DLCO when considering BSA. Conclusion DLNO is a performance-limiting factor in only Boston qualifiers. This suggests that alveolar-capillary membrane conductance is a limitation to performance in faster marathoners. Additionally, DLNO/BSA predicts marathon finishing time and aerobic capacity more accurately than DLCO. PMID:22984520

  3. Reduction in Post-Marathon Peak Oxygen Consumption: Sign of Cardiac Fatigue in Amateur Runners?

    PubMed Central

    Sierra, Ana Paula Rennó; da Silveira, Anderson Donelli; Francisco, Ricardo Contesini; Barretto, Rodrigo Bellios de Mattos; Sierra, Carlos Anibal; Meneghelo, Romeu Sergio; Kiss, Maria Augusta Peduti Dal Molin; Ghorayeb, Nabil; Stein, Ricardo

    2016-01-01

    Background Prolonged aerobic exercise, such as running a marathon, produces supraphysiological stress that can affect the athlete's homeostasis. Some degree of transient myocardial dysfunction ("cardiac fatigue") can be observed for several days after the race. Objective To verify if there are changes in the cardiopulmonary capacity, and cardiac inotropy and lusitropy in amateur marathoners after running a marathon. Methods The sample comprised 6 male amateur runners. All of them underwent cardiopulmonary exercise testing (CPET) one week before the São Paulo Marathon, and 3 to 4 days after that race. They underwent echocardiography 24 hours prior to and immediately after the marathon. All subjects were instructed not to exercise, to maintain their regular diet, ingest the same usual amount of liquids, and rest at least 8 hours a day in the period preceding the CPET. Results The athletes completed the marathon in 221.5 (207; 250) minutes. In the post-marathon CPET, there was a significant reduction in peak oxygen consumption and peak oxygen pulse compared to the results obtained before the race (50.75 and 46.35 mL.kg-1 .min-1; 19.4 and 18.1 mL.btm, respectively). The echocardiography showed a significant reduction in the s' wave (inotropic marker), but no significant change in the E/e' ratio (lusitropic marker). Conclusions In amateur runners, the marathon seems to promote changes in the cardiopulmonary capacity identified within 4 days after the race, with a reduction in the cardiac contractility. Such changes suggest that some degree of "cardiac fatigue" can occur. PMID:26760783

  4. Marathon-induced pulmonary edema of a patient with transient dyspnea.

    PubMed

    Miyazawa, Ryo; Morita, Yuka; Okajima, Yuka; Matsusako, Masaki; Kurihara, Yasuyuki

    2015-10-01

    We report a case of a 31-year-old healthy man with marathon-induced pulmonary edema. Chest radiograph revealed pulmonary edema without cardiomegaly. Contrast-enhanced chest computed tomography (CT) revealed transient pulmonary edema without filling-defect in pulmonary arteries. As marathon running increases in popularity, radiologists and emergency physicians should be familiar with diagnosis of this entity on chest radiograph, avoiding unnecessary CT examination without additional clinical information.

  5. Marathon-induced pulmonary edema of a patient with transient dyspnea.

    PubMed

    Miyazawa, Ryo; Morita, Yuka; Okajima, Yuka; Matsusako, Masaki; Kurihara, Yasuyuki

    2015-10-01

    We report a case of a 31-year-old healthy man with marathon-induced pulmonary edema. Chest radiograph revealed pulmonary edema without cardiomegaly. Contrast-enhanced chest computed tomography (CT) revealed transient pulmonary edema without filling-defect in pulmonary arteries. As marathon running increases in popularity, radiologists and emergency physicians should be familiar with diagnosis of this entity on chest radiograph, avoiding unnecessary CT examination without additional clinical information. PMID:26324381

  6. Myosin Light Chain Kinase (MLCK) Gene Influences Exercise Induced Muscle Damage during a Competitive Marathon.

    PubMed

    Del Coso, Juan; Valero, Marjorie; Lara, Beatriz; Salinero, Juan José; Gallo-Salazar, César; Areces, Francisco

    2016-01-01

    Myosin light chain kinase (MLCK) phosphorylates the regulatory light chain (RLC) of myosin producing increases in force development during skeletal muscle contraction. It has been suggested that MLCK gene polymorphisms might alter RLC phosphorylation thereby decreasing the ability to produce force and to resist strain during voluntary muscle contractions. Thus, the genetic variations in the MLCK gene might predispose some individuals to higher values of muscle damage during exercise, especially during endurance competitions. The aim of this investigation was to determine the influence of MLCK genetic variants on exercise-induced muscle damage produced during a marathon. Sixty-seven experienced runners competed in a marathon race. The MLCK genotype (C37885A) of these marathoners was determined. Before and after the race, a sample of venous blood was obtained to assess changes in serum myoglobin concentrations and leg muscle power changes were measured during a countermovement jump. Self-reported leg muscle pain and fatigue were determined by questionnaires. A total of 59 marathoners (88.1%) were CC homozygotes and 8 marathoners (11.9%) were CA heterozygotes. The two groups of participants completed the race with a similar time (228 ± 33 vs 234 ± 39 min; P = 0.30) and similar self-reported values for fatigue (15 ± 2 vs 16 ± 2 A.U.; P = 0.21) and lower-limb muscle pain (6.2 ± 1.7 vs 6.6 ± 1.8 cm; P = 0.29). However, CC marathoners presented higher serum myoglobin concentrations (739 ± 792 vs 348 ± 144 μg·mL-1; P = 0.03) and greater pre-to-post- race leg muscle power reduction (-32.7 ± 15.7 vs -21.2 ± 21.6%; P = 0.05) than CA marathoners. CA heterozygotes for MLCK C37885A might present higher exercise-induced muscle damage after a marathon competition than CC counterparts.

  7. Alumina+Silica+/-Germanium Alteration in Smectite-Bearing Marathon Valley, Endeavour Crater Rim, Mars

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.; Gellert, R.; Van Bommel, S.; Arvidson, R. E.; Clark, B. C.; Ming, D. W.; Schroeder, C.; Yen, A. S.; Fox, V. K.; Farrand, W. H.; Jolliff, B. L.

    2016-01-01

    Mars Exploration Rover Opportunity has been exploring Mars for 12+ years, and is presently investigating the geology of a western rim segment of 22 kilometers diameter, Noachian- aged Endeavour crater. The Alpha Particle X-ray Spectrometer has determined the compositions of a pre-impact lithology, the Matijevic fm., and polymict impact breccias ejected from the crater, the Shoemaker fm. Opportunity is now investigating a region named Marathon Valley that cuts southwest-northeast through the central portion of the rim segment and provides a window into the lower stratigraphic record. (Geographic names used here are informal.) At the head of Marathon Valley, referred to here as Upper Marathon Valley, is a shallow, ovoid depression approximately 25×35 millimeters in size, named Spirit of Saint Louis. Layering inside Spirit of Saint Louis appears continuous with the Upper Marathon Valley rocks outside, indicating they are coeval. Spirit of Saint Louis is partly bounded by approximately 10-20 centimeters wide zone containing reddish altered rocks (red zone). Red zones also form prominent curvilinear features in Marathon Valley. Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) spectra provide evidence for a really extensive Fe-Mg smectite in the Marathon Valley region, indicating distinct styles of aqueous alteration. The CRISM detections of smectites are based on metal-OH absorptions at approximately 2.3 and 2.4 micron that are at least two times the background noise level.

  8. A multiplexed nucleic acid microsystem for point-of-care detection of HIV co-infection with MTB and PCP.

    PubMed

    Xu, Lingjia; Kong, Jilie

    2013-12-15

    Many individuals infected with the human immunodeficiency virus (HIV), especially children in African countries, die of co-infections with Mycobacterium tuberculosis (MTB) (coinfection rate: 50%) or Pneumocystis carinii pneumonia (PCP) (coinfection rate: 81%). The present proposal describes a rapid, portable, low-cost, multiplexed point-of-care diagnostic technique for simultaneously detecting HIV, MTB, and PCP. This technique incorporates a creative micro-device (hardware) and a loop-mediated isothermal amplification strategy (software). PMID:24209377

  9. Does Multi-morbidity Mediate the Effect of Socioeconomics on Self-rated Health? Cross-country Differences

    PubMed Central

    Assari, Shervin; Lankarani, Maryam Moghani

    2015-01-01

    Background: This study explored cross-country differences in how multi-morbidity explains the effects of socioeconomic characteristics on self-rated health. Methods: The study borrowed data from the Research on Early Life and Aging Trends and Effects. Participants were 44,530 individuals (age > 65 years) who were sampled from 15 countries (i.e. United States, China, India, Russia, Costa Rica, Puerto Rico, Mexico, Argentina, Barbados, Brazil, Chile, Cuba, Uruguay, Ghana and South Africa). Multi-morbidity was measured as number of chronic medical conditions. In Model I, main effects of socioeconomic factors on self-rated health were calculated using country-specific logistic regressions. In Model II, number of chronic conditions were also added to the models to find changes in coefficients for demographic and socioeconomic factors. Results: In the United States, number of chronic medical conditions explained the effect of income on subjective health. In Puerto Rico, number of chronic medical conditions explained the effect of marital status on subjective health. In Costa Rica, Argentina, Barbados, Cuba, and Uruguay, number of chronic medical conditions explained gender disparities in subjective health. In China, Mexico, Brazil, Russia, Chile, India, Ghana and South Africa, number of chronic medical conditions did not explain the effect of demographic or socioeconomic factors on subjective health. Conclusions: Multi-morbidity explains the effect of demographic and socioeconomic factors on subjective health in some but not other countries. Further research is needed. PMID:26445632

  10. Exercise Intensity and Pacing Strategy of Cross-country Skiers during a 10 km Skating Simulated Race.

    PubMed

    Formenti, Damiano; Rossi, Alessio; Calogiuri, Giovanna; Thomassen, Tor Oskar; Scurati, Raffaele; Weydahl, Andi

    2015-01-01

    The aim of this study was to observe the cardiovascular demands by monitoring the heart rate (HR) and the pacing strategy by evaluating the speed during a simulated cross-country skiing race. Eleven skiers (16.45 ± 1.67 yrs; 21.32 ± 2.03 kg m(-2); 72.35 ± 4.69 mL min(-1) kg(-1)) competed in a 10 km event divided into four laps. The HR profile was classified into four intensity zones. The skiers spent 66.84 ± 23.64% and 31.82 ± 23.77% of the total time above 90% and at 80-90% of the HRmax respectively, whereas the lower zones were negligible. During the event, a progressive increase in intensity was observed: HRmean raised by 2.42% in the last versus the first lap (p < 0.001). The skiers decreased their speed in the second (p = 0.017) and the third laps (p < 0.001) compared to with the first lap. In the fourth lap the skiers increased the speed slightly but without statistical difference. The speed maintained by the skiers resulted in the adoption of a reverse J-shaped pacing strategy.

  11. [The application of the emulsified turpentine baths for the correction of the functional state of the cross-country skiers].

    PubMed

    Garnov, I O; Kuchin, A V; Loginova, T P; Varlamova, N G; Boiko, E R

    2016-01-01

    The baths with emulsified turpentine find the wide application in balneotherapy. They produce especially pronounced beneficial prophylactic effects in the patients presenting with microtrombosis and microvascular stasis. Moreover, these baths may be prescribed to improve microcirculation, increase the functional reserves and physical capacity in the athletes. At the same time, the current literature appears to contain no scientific publications on the application of emulsified turpentine baths for the restoration of the physical capacity of the professional ski runners. The lack of relevant information motivated the study reported in the present article. The main objective of the study involving 10 subjects was to evaluate the effectiveness of the modified emulsified turpentine baths as a method by which to restore and enhance the physical capacity of the professional cross-country skiers. The physical capacity of the athletes was evaluated from the results of the bicycle ergometer exercise test with the use of the «Oxycon Pro» system. The data obtained suggest that a course of the emulsified turpentine baths increases the activity of the cardiorespiratory system, improves the physical capacity, and enhances the functional reserves of the body in the anaerobic zone.

  12. Gender differences in endurance performance by elite cross-country skiers are influenced by the contribution from poling.

    PubMed

    Sandbakk, Ø; Ettema, G; Holmberg, H-C

    2014-02-01

    Greater gender differences have been found in exercise modes where the upper body is involved. Therefore, the present study investigated the influence of poling on gender differences in endurance performance by elite cross-country skiers. Initially, the performance of eight male and eight female sprint skiers was compared during four different types of exercise involving different degrees of poling: double poling (DP), G3 skating, and diagonal stride (DIA) techniques during treadmill roller skiing, and treadmill running (RUN). Thereafter, DP was examined for physiological and kinematic parameters. The relative gender differences associated with the DP, G3, DIA and RUN performances were approximately 20%, 17%, 14%, and 12%, respectively. Thus, the type of exercise exerted an overall effect on the relative gender differences (P < 0.05). In connection with DP, the men achieved 63%, 16%, and 8% higher VO2peak than the women in absolute terms and with normalization for total and fat-free body mass (all P < 0.05). The DP VO2peak in percentage of VO2max in RUN was higher in men (P < 0.05). The gender difference in DP peak cycle length was 23% (P < 0.05). In conclusion, the present investigation demonstrates that the gender difference in performance by elite sprint skiers is enhanced when the contribution from poling increases.

  13. Muscle fatigue during cross country sprint assessed by activation patterns and electromyographic signals time-frequency analysis.

    PubMed

    Zory, R; Molinari, F; Knaflitz, M; Schena, F; Rouard, A

    2011-12-01

    The aims of this study were as follows: (i) analysis of activation patterns during the spurt of two heats of a cross country skiing sprint with the double poling technique and (ii) quantification of muscle fatigue of the investigated muscles. Eight elite skiers were tested and surface electromyographic signals (EMG) were recorded from seven muscles of the upper and lower limbs. For each subject and each muscle, the activation intervals were calculated for relying on a double-threshold statistical detector and the average rectified value was calculated on each activation interval. The detected activations were processed by a time-frequency algorithm in order to assess the progression of muscle fatigue. The EMG activation patterns and EMG amplitude highlighted no significant difference between the two spurts, despite a generally lower speed in the second spurt. The frequency analysis showed that upper body muscles are the first to be affected by fatigue and that clear signs of muscle fatigue appear right from the first spurt of the sprint simulation (i.e., biceps and triceps brachii) with a decrease in the instantaneous mean frequency. Biceps brachii activations and fatigue demonstrated the involvement of this muscle in propulsion.

  14. An inertial sensor-based system for spatio-temporal analysis in classic cross-country skiing diagonal technique.

    PubMed

    Fasel, Benedikt; Favre, Julien; Chardonnens, Julien; Gremion, Gérald; Aminian, Kamiar

    2015-09-18

    The present study proposes a method based on ski fixed inertial sensors to automatically compute spatio-temporal parameters (phase durations, cycle speed and cycle length) for the diagonal stride in classical cross-country skiing. The proposed system was validated against a marker-based motion capture system during indoor treadmill skiing. Skiing movement of 10 junior to world-cup athletes was measured for four different conditions. The accuracy (i.e. median error) and precision (i.e. interquartile range of error) of the system was below 6 ms for cycle duration and ski thrust duration and below 35 ms for pole push duration. Cycle speed precision (accuracy) was below 0.1m/s (0.00 5m/s) and cycle length precision (accuracy) was below 0.15m (0.005 m). The system was sensitive to changes of conditions and was accurate enough to detect significant differences reported in previous studies. Since capture volume is not limited and setup is simple, the system would be well suited for outdoor measurements on snow.

  15. [The application of the emulsified turpentine baths for the correction of the functional state of the cross-country skiers].

    PubMed

    Garnov, I O; Kuchin, A V; Loginova, T P; Varlamova, N G; Boiko, E R

    2016-01-01

    The baths with emulsified turpentine find the wide application in balneotherapy. They produce especially pronounced beneficial prophylactic effects in the patients presenting with microtrombosis and microvascular stasis. Moreover, these baths may be prescribed to improve microcirculation, increase the functional reserves and physical capacity in the athletes. At the same time, the current literature appears to contain no scientific publications on the application of emulsified turpentine baths for the restoration of the physical capacity of the professional ski runners. The lack of relevant information motivated the study reported in the present article. The main objective of the study involving 10 subjects was to evaluate the effectiveness of the modified emulsified turpentine baths as a method by which to restore and enhance the physical capacity of the professional cross-country skiers. The physical capacity of the athletes was evaluated from the results of the bicycle ergometer exercise test with the use of the «Oxycon Pro» system. The data obtained suggest that a course of the emulsified turpentine baths increases the activity of the cardiorespiratory system, improves the physical capacity, and enhances the functional reserves of the body in the anaerobic zone. PMID:27213946

  16. Performance differences when using 26- and 29-inch-wheel bikes in Swiss National Team cross-country mountain bikers.

    PubMed

    Steiner, Thomas; Müller, Beat; Maier, Thomas; Wehrlin, Jon Peter

    2016-08-01

    The purpose of this study was to analyse the effect of bike type - the 26-inch-wheel bike (26" bike) and the 29-inch-wheel bike (29" bike) - on performance in elite mountain bikers. Ten Swiss National Team athletes (seven males, three females) completed six trials with individual start on a simulated cross-country course with 35 min of active recovery between trials (three trials on a 26" bike and three trials on a 29" bike, alternate order, randomised start-bike). The course consisted of two separate sections expected to favour either the 29" bike (section A) or the 26" bike (section B). For each trial performance, power output, cadence and heart rate were recorded and athletes' experiences were documented. Mean overall performance (time: 304 ± 27 s vs. 311 ± 29 s; P < 0.01) and performance in sections A (P < 0.001) and B (P < 0.05) were better when using the 29" bike. No significant differences were observed for power output, cadence or heart rate. Athletes rated the 29" bike as better for performance in general, passing obstacles and traction. The 29" bike supports superior performance for elite mountain bikers, even on sections supposed to favour the 26" bike.

  17. An inertial sensor-based system for spatio-temporal analysis in classic cross-country skiing diagonal technique.

    PubMed

    Fasel, Benedikt; Favre, Julien; Chardonnens, Julien; Gremion, Gérald; Aminian, Kamiar

    2015-09-18

    The present study proposes a method based on ski fixed inertial sensors to automatically compute spatio-temporal parameters (phase durations, cycle speed and cycle length) for the diagonal stride in classical cross-country skiing. The proposed system was validated against a marker-based motion capture system during indoor treadmill skiing. Skiing movement of 10 junior to world-cup athletes was measured for four different conditions. The accuracy (i.e. median error) and precision (i.e. interquartile range of error) of the system was below 6 ms for cycle duration and ski thrust duration and below 35 ms for pole push duration. Cycle speed precision (accuracy) was below 0.1m/s (0.00 5m/s) and cycle length precision (accuracy) was below 0.15m (0.005 m). The system was sensitive to changes of conditions and was accurate enough to detect significant differences reported in previous studies. Since capture volume is not limited and setup is simple, the system would be well suited for outdoor measurements on snow. PMID:26209087

  18. Exercise-associated collapse care matrix in the marathon.

    PubMed

    Roberts, William O

    2007-01-01

    Exercise-associated collapse (EAC) was developed as a marathon collapse classification matrix to speed clinical decision making and improve care. The definition was simply stated as the need for assistance during or immediately after endurance activity that specifically excluded cardiac arrest, insulin shock, anaphylaxis, trauma, skin conditions and orthopedic injuries. The presenting symptoms were neither specific nor sensitive and the initial classification, based on presenting rectal temperature, neurological status and ability to walk, was intended to shape the on-site medical intervention. The treatment of EAC centres on fluid redistribution and replacement to improve cerebral and core organ circulation and body temperature correction if needed. Most runners are discharged from the medical area in the company of another person.

  19. Exercise and neuromodulators: choline and acetylcholine in marathon runners

    NASA Technical Reports Server (NTRS)

    Conlay, L. A.; Sabounjian, L. A.; Wurtman, R. J.

    1992-01-01

    Certain neurotransmitters (i.e., acetylcholine, catecholamines, and serotonin) are formed from dietary constituents (i.e., choline, tyrosine and tryptophan). Changing the consumption of these precursors alters release of their respective neurotransmitter products. The neurotransmitter acetylcholine is released from the neuromuscular junction and from brain. It is formed from choline, a common constituent in fish, liver, and eggs. Choline is also incorporated into cell membranes; membranes may likewise serve as an alternative choline source for acetylcholine synthesis. In trained athletes, running a 26 km marathon reduced plasma choline by approximately 40%, from 14.1 to 8.4 uM. Changes of similar magnitude have been shown to reduce acetylcholine release from the neuromuscular junction in vivo. Thus, the reductions in plasma choline associated with strenuous exercise may reduce acetylcholine release, and could thereby affect endurance or performance.

  20. [Sudden cardiac death during a city marathon run].

    PubMed

    Beutler, J; Schmid, E; Fischer, S; Hürlimann, S; Konrad, C

    2015-06-01

    Sudden cardiac death (SCD) in young athletes during physical stress is a rare event with an incidence of 1-3 deaths per 100,000 athletes per year. A coronary anomaly is the second most common cause of death following hypertrophic cardiomyopathy. Symptomatic prodromes occur in 20% of cases prior to the SCD event. This case report describes a 35-year-old male who collapsed near the finishing line of a half marathon run. Despite immediate resuscitation attempts and initial return of spontaneous circulation (ROSC), a pulseless electrical activity (PEA) followed and the patient died 1 h after arrival in the resuscitation unit. The autopsy revealed an anomalous left coronary artery (ALCA), which can lead to ischemia of the respective heart muscles under severe stress.

  1. MicroRNAs as Biomarkers for Acute Atrial Remodeling in Marathon Runners (The miRathon Study – A Sub-Study of the Munich Marathon Study)

    PubMed Central

    Hildebrand, Bianca; Kääb, Stefan; Hoster, Eva; Klier, Ina; Martens, Eimo; Hanley, Alan; Hanssen, Henner; Halle, Martin; Nickel, Thomas

    2016-01-01

    Introduction Physical activity is beneficial for individual health, but endurance sport is associated with the development of arrhythmias like atrial fibrillation. The underlying mechanisms leading to this increased risk are still not fully understood. MicroRNAs are important mediators of proarrhythmogenic remodeling and have potential value as biomarkers in cardiovascular diseases. Therefore, the objective of our study was to determine the value of circulating microRNAs as potential biomarkers for atrial remodeling in marathon runners (miRathon study). Methods 30 marathon runners were recruited into our study and were divided into two age-matched groups depending on the training status: elite (ER, ≥55 km/week, n = 15) and non-elite runners (NER, ≤40 km/week, n = 15). All runners participated in a 10 week training program before the marathon. MiRNA plasma levels were measured at 4 time points: at baseline (V1), after a 10 week training period (V2), immediately after the marathon (V3) and 24h later (V4). Additionally, we obtained clinical data including serum chemistry and echocardiography at each time point. Results MiRNA plasma levels were similar in both groups over time with more pronounced changes in ER. After the marathon miR-30a plasma levels increased significantly in both groups. MiR-1 and miR-133a plasma levels also increased but showed significant changes in ER only. 24h after the marathon plasma levels returned to baseline. MiR-26a decreased significantly after the marathon in elite runners only and miR-29b showed a non-significant decrease over time in both groups. In ER miRNA plasma levels showed a significant correlation with LA diameter, in NER miRNA plasma levels did not correlate with echocardiographic parameters. Conclusion MiRNAs were differentially expressed in the plasma of marathon runners with more pronounced changes in ER. Plasma levels in ER correlate with left atrial diameter suggesting that circulating miRNAs could potentially serve

  2. Track and Field Guide including Cross Country, Pentathlon Scoring Tables and Rules for Intercollegiate Meets and Championships with Official Rules. Janauary 1974-January 1976.

    ERIC Educational Resources Information Center

    Thompson, Donnis H., Ed.

    This guide includes information on cross country running, pentathlon scoring tables, and rules for intercollegiate meets and championships, following an introductory portion on the organization's credo and standards. The first section covers track activities for children, coaching techniques, the benefits of weight training, and some practical…

  3. Cross-Country Evidence on Teacher Performance Pay. Program on Education Policy and Governance Working Papers Series. PEPG 10-11

    ERIC Educational Resources Information Center

    Woessmann, Ludger

    2010-01-01

    The general-equilibrium effects of performance-related teacher pay include long-term incentive and teacher-sorting mechanisms that usually elude experimental studies but are captured in cross-country comparisons. Combining country-level performance-pay measures with rich PISA-2003 international achievement microdata, this paper estimates…

  4. Reliability, factor structure, and measurement invariance of the Dominic Interactive across European countries: Cross-country utility of a child mental health self-report.

    PubMed

    Kuijpers, Rowella C W M; Otten, Roy; Vermulst, Ad A; Pez, Ondine; Bitfoi, Adina; Carta, Mauro; Goelitz, Dietmar; Keyes, Katherine; Koç, Ceren; Lesinskiene, Sigita; Mihova, Zlatka; Engels, Rutger C M E; Kovess, Viviane

    2016-05-01

    Large-scale international surveys are important to globally evaluate, monitor, and promote children's mental health. However, use of young children's self-reports in these studies is still controversial. The Dominic Interactive, a computerized DSM-IV-based child mental health self-report questionnaire, has unique characteristics that may make it preeminently appropriate for usage in cross-country comparisons. This study aimed to determine scale score reliabilities (omega) of the Dominic Interactive in a sample of 8,135 primary school children, ages 6-11 years old, in 7 European countries, to confirm the proposed 7-scale factor structure, and to test for measurement invariance of scale and item scores across countries. Omega reliability values for scale scores were good to high in every country, and the factor structure was confirmed for all countries. A thorough examination of measurement invariance provided evidence for cross-country test score comparability of 5 of the 7 scales and partial scale score invariance of 2 anxiety scales. Possible explanations for this partial invariance include cross-country differences in conceptualizing items and defining what is socially and culturally acceptable anxiety. The convincing evidence for validity of score interpretation makes the Dominic Interactive an indispensable tool for cross-country screening purposes. (PsycINFO Database Record PMID:26237209

  5. Spinal alignment, mobility of the hip and thoracic spine and prevalence of low back pain in young elite cross-country skiers.

    PubMed

    Alricsson, Marie; Björklund, Glenn; Cronholm, Martin; Olsson, Oscar; Viklund, Peter; Svantesson, Ulla

    2016-02-01

    This study investigated the association between spinal alignment, mobility of the hips and the thoracic spine and low back pain in adolescent cross-country skiers. Cohort of 51 elite cross-country skiers from a cross-country skiing high school in Sweden participated in the study. Sagittal spinal alignment, active range of motion in flexion, extension and rotation of the thoracic spine as well as passive and active extension of the hips were measured. The participants also completed a questionnaire regarding training, competition, skiing technique and occurrence of low back pain. A simple linear regression was calculated to predict pain score based on thoraco-lumbar relation, with a significant (P<0.05) regression equation of y=-0.069x+2.280 (standard error of estimate, 0.034). Participants with greater lordosis than kyphosis were more likely to suffer from low back pain than subjects without this offset. Thoracic mobility and passive or active hip extension showed no correlation with low back pain. Sagittal spinal alignment seems to be related with low back pain among young elite cross-country skiers. This study shows that range of motion of the thoracic spine and hips do not have an effect on the prevalence of low back pain in this population.

  6. Cross-Country Skiing as a Self-Efficacy Intervention with an Adolescent Female: An Innovative Application of Bandura's Theory to Therapeutic Recreation.

    ERIC Educational Resources Information Center

    Ferguson, Daniel D.; Jones, Karna

    2001-01-01

    Used Bandura's theory of self-efficacy as a basis for designing a therapeutic recreation intervention (cross-country skiing) for an adolescent girl with severe depression and oppositional defiant disorder in a long-term residential treatment facility. The intervention facilitated increased self- confidence and helped her discover positive ways to…

  7. Spinal alignment, mobility of the hip and thoracic spine and prevalence of low back pain in young elite cross-country skiers

    PubMed Central

    Alricsson, Marie; Björklund, Glenn; Cronholm, Martin; Olsson, Oscar; Viklund, Peter; Svantesson, Ulla

    2016-01-01

    This study investigated the association between spinal alignment, mobility of the hips and the thoracic spine and low back pain in adolescent cross-country skiers. Cohort of 51 elite cross-country skiers from a cross-country skiing high school in Sweden participated in the study. Sagittal spinal alignment, active range of motion in flexion, extension and rotation of the thoracic spine as well as passive and active extension of the hips were measured. The participants also completed a questionnaire regarding training, competition, skiing technique and occurrence of low back pain. A simple linear regression was calculated to predict pain score based on thoraco-lumbar relation, with a significant (P<0.05) regression equation of y=−0.069x+2.280 (standard error of estimate, 0.034). Participants with greater lordosis than kyphosis were more likely to suffer from low back pain than subjects without this offset. Thoracic mobility and passive or active hip extension showed no correlation with low back pain. Sagittal spinal alignment seems to be related with low back pain among young elite cross-country skiers. This study shows that range of motion of the thoracic spine and hips do not have an effect on the prevalence of low back pain in this population. PMID:26933656

  8. Running Pace Decrease during a Marathon Is Positively Related to Blood Markers of Muscle Damage

    PubMed Central

    Del Coso, Juan; Fernández, David; Abián-Vicen, Javier; Salinero, Juan José; González-Millán, Cristina; Areces, Francisco; Ruiz, Diana; Gallo, César; Calleja-González, Julio; Pérez-González, Benito

    2013-01-01

    Background Completing a marathon is one of the most challenging sports activities, yet the source of running fatigue during this event is not completely understood. The aim of this investigation was to determine the cause(s) of running fatigue during a marathon in warm weather. Methodology/Principal Findings We recruited 40 amateur runners (34 men and 6 women) for the study. Before the race, body core temperature, body mass, leg muscle power output during a countermovement jump, and blood samples were obtained. During the marathon (27 °C; 27% relative humidity) running fatigue was measured as the pace reduction from the first 5-km to the end of the race. Within 3 min after the marathon, the same pre-exercise variables were obtained. Results Marathoners reduced their running pace from 3.5 ± 0.4 m/s after 5-km to 2.9 ± 0.6 m/s at the end of the race (P<0.05), although the running fatigue experienced by the marathoners was uneven. Marathoners with greater running fatigue (> 15% pace reduction) had elevated post-race myoglobin (1318 ± 1411 v 623 ± 391 µg L−1; P<0.05), lactate dehydrogenase (687 ± 151 v 583 ± 117 U L−1; P<0.05), and creatine kinase (564 ± 469 v 363 ± 158 U L−1; P = 0.07) in comparison with marathoners that preserved their running pace reasonably well throughout the race. However, they did not differ in their body mass change (−3.1 ± 1.0 v −3.0 ± 1.0%; P = 0.60) or post-race body temperature (38.7 ± 0.7 v 38.9 ± 0.9 °C; P = 0.35). Conclusions/Significance Running pace decline during a marathon was positively related with muscle breakdown blood markers. To elucidate if muscle damage during a marathon is related to mechanistic or metabolic factors requires further investigation. PMID:23460881

  9. Risk Factors for Self-Reported Exercise-Related Leg Pain in High School Cross-Country Athletes

    PubMed Central

    Reinking, Mark F.; Austin, Tricia M.; Hayes, Ann M.

    2010-01-01

    Abstract Context: Prevention of exercise-related leg pain (ERLP) has not been successful because ERLP risk factors are not well known. Objective: To determine the percentage of high school cross-country (XC) athletes who reported a history of ERLP in their running careers, to identify the percentage of athletes who reported an occurrence of ERLP during 1 XC season, and to investigate the association of selected factors (age, high school year, years of high school running, sex, ERLP history, body mass index [BMI], foot type, and training distance) and the occurrence of ERLP. Design: Prospective cohort study. Setting: Six local high schools. Patients or Other Participants: One hundred twenty-five high school XC athletes (62 females, 63 males). Main Outcome Measure(s): All athletes completed an initial ERLP questionnaire, and foot type was visually assessed. After the season, athletes were asked to complete a Web-based questionnaire regarding the seasonal occurrence of ERLP. Statistical analyses of differences (t tests) and associations (χ2, relative risk) were conducted. Results: A total of 103 of the 125 athletes (82.4%) reported a history of ERLP, with 81 athletes reporting ERLP occurrence within the month preceding completion of the initial questionnaire. Bilateral medial leg pain was the most common ERLP presentation. More than half of the athletes (58.4%) with an ERLP history reported that the pain had interfered with XC participation. Ninety-three athletes responded to the postseason questionnaire, and 45 (48.0%) reported ERLP seasonal occurrence. Most athletes (97.8%) who experienced the seasonal occurrence of ERLP had a history of ERLP. No associations were noted between ERLP history or seasonal occurrence and age, high school year, years of high school running, sex, BMI, foot type, or training distance. Conclusions: Both a history of ERLP and the seasonal occurrence of ERLP were common among these XC athletes. The only risk factor identified for ERLP season

  10. Is inequality at the heart of it? Cross-country associations of income inequality with cardiovascular diseases and risk factors.

    PubMed

    Kim, Daniel; Kawachi, Ichiro; Hoorn, Stephen Vander; Ezzati, Majid

    2008-04-01

    Despite a number of cross-national studies that have examined the associations between income inequality and broad health outcomes such as life expectancy and all-cause mortality, investigations of the cross-country relations between income inequality and cardiovascular disease (CVD) morbidity, mortality, and risk factors are sparse. We analyzed the cross-national relations between income inequality and age-standardized mean body mass index (BMI), serum total cholesterol, systolic blood pressure (SBP), obesity prevalence, smoking impact ratio (SIR), and age-standardized and age-specific disability-adjusted life-years (DALYs) and mortality rates from coronary heart disease (CHD) and stroke, controlling for multiple country-level factors and specifying 5- to 10-year lag periods. In multivariable analyses primarily limited to industrialized countries, countries in the middle and highest (vs. lowest) tertiles of income inequality had higher absolute age-standardized obesity prevalences in both sexes. Higher income inequality was also related to higher mean SBP in both sexes, and higher SIR in women. In analyses of larger sets of countries with available data, positive associations were observed between higher income inequality and mean BMI, obesity prevalence, and CHD DALYs and mortality rates. Associations with stroke outcomes were inverse, yet became positive with the inclusion of eastern bloc and other countries in recent economic/political transition. China was also identified to be an influential data point, with the positive associations with stroke mortality rates becoming attenuated with its inclusion. Overall, our findings are compatible with harmful effects of income inequality at the national scale on CVD morbidity, mortality, and selected risk factors, particularly BMI/obesity. Future studies should consider income inequality as an independent contributor to variations in CVD burden globally.

  11. Automatic Classification of the Sub-Techniques (Gears) Used in Cross-Country Ski Skating Employing a Mobile Phone

    PubMed Central

    Stöggl, Thomas; Holst, Anders; Jonasson, Arndt; Andersson, Erik; Wunsch, Tobias; Norström, Christer; Holmberg, Hans-Christer

    2014-01-01

    The purpose of the current study was to develop and validate an automatic algorithm for classification of cross-country (XC) ski-skating gears (G) using Smartphone accelerometer data. Eleven XC skiers (seven men, four women) with regional-to-international levels of performance carried out roller skiing trials on a treadmill using fixed gears (G2left, G2right, G3, G4left, G4right) and a 950-m trial using different speeds and inclines, applying gears and sides as they normally would. Gear classification by the Smartphone (on the chest) and based on video recordings were compared. Formachine-learning, a collective database was compared to individual data. The Smartphone application identified the trials with fixed gears correctly in all cases. In the 950-m trial, participants executed 140 ± 22 cycles as assessed by video analysis, with the automatic Smartphone application giving a similar value. Based on collective data, gears were identified correctly 86.0% ± 8.9% of the time, a value that rose to 90.3% ± 4.1% (P < 0.01) with machine learning from individual data. Classification was most often incorrect during transition between gears, especially to or from G3. Identification was most often correct for skiers who made relatively few transitions between gears. The accuracy of the automatic procedure for identifying G2left, G2right, G3, G4left and G4right was 96%, 90%, 81%, 88% and 94%, respectively. The algorithm identified gears correctly 100% of the time when a single gear was used and 90% of the time when different gears were employed during a variable protocol. This algorithm could be improved with respect to identification of transitions between gears or the side employed within a given gear. PMID:25365459

  12. Assessment of Heart Rate Variability Thresholds from Incremental Treadmill Tests in Five Cross-Country Skiing Techniques.

    PubMed

    Mendia-Iztueta, Ibai; Monahan, Kristen; Kyröläinen, Heikki; Hynynen, Esa

    2016-01-01

    The assessment of heart rate variability (HRV) thresholds (HRVTs) as an alternative of Ventilatory thresholds (VTs) is a relatively new approach with increasing popularity which has not been conducted in cross-country (XC) skiing yet. The main purpose of the present study was to assess HRVTs in the five main XC skiing-related techniques, double poling (DP), diagonal striding (DS), Nordic walking (NW), V1 skating (V1), and V2 skating (V2).Ten competitive skiers completed these incremental treadmill tests until exhaustion with a minimum of one to two recovery days in between each test. Ventilatory gases, HRV and poling frequencies were measured. The first HRV threshold (HRVT1) was assessed using two time-domain analysis methods, and the second HRV threshold (HRVT2) was assessed using two non-time varying frequency-domain analysis methods. HRVT1 was assessed by plotting the mean successive difference (MSD) and standard deviation (SD) of normalized R-R intervals to workload. HRVT1 was assessed by plotting high frequency power (HFP) and the HFP relative to respiratory sinus arrhythmia (HFPRSA) with workload. HRVTs were named after their methods (HRVT1-SD; HRVT1-MSD; HRVT2-HFP; HRVT2-HFP-RSA). The results showed that the only cases where the proposed HRVTs were good assessors of VTs were the HRVT1-SD of the DS test, the HRVT1-MSD of the DS and V2 tests, and the HRVT2-HFP-RSA of the NW test. The lack of a wider success of the assessment of HRVTs was reasoned to be mostly due to the high entrainment between the breathing and poling frequencies. As secondary finding, a novel Cardiolocomotor coupling mode was observed in the NW test. This new Cardiolocoomtor coupling mode corresponded to the whole bilateral poling cycle instead of corresponding to each poling action as it was reported to the date by the existing literature. PMID:26727112

  13. Descriptive, cross-country analysis of the nurse practitioner workforce in six countries: size, growth, physician substitution potential

    PubMed Central

    Maier, Claudia B; Barnes, Hilary; Aiken, Linda H; Busse, Reinhard

    2016-01-01

    Objectives Many countries are facing provider shortages and imbalances in primary care or are projecting shortfalls for the future, triggered by the rise in chronic diseases and multimorbidity. In order to assess the potential of nurse practitioners (NPs) in expanding access, we analysed the size, annual growth (2005–2015) and the extent of advanced practice of NPs in 6 Organisation for Economic Cooperation and Development (OECD) countries. Design Cross-country data analysis of national nursing registries, regulatory bodies, statistical offices data as well as OECD health workforce and population data, plus literature scoping review. Setting/participants NP and physician workforces in 6 OECD countries (Australia, Canada, Ireland, the Netherlands, New Zealand and USA). Primary and secondary outcome measures The main outcomes were the absolute and relative number of NPs per 100 000 population compared with the nursing and physician workforces, the compound annual growth rates, annual and median percentage changes from 2005 to 2015 and a synthesis of the literature on the extent of advanced clinical practice measured by physician substitution effect. Results The USA showed the highest absolute number of NPs and rate per population (40.5 per 100 000 population), followed by the Netherlands (12.6), Canada (9.8), Australia (4.4), and Ireland and New Zealand (3.1, respectively). Annual growth rates were high in all countries, ranging from annual compound rates of 6.1% in the USA to 27.8% in the Netherlands. Growth rates were between three and nine times higher compared with physicians. Finally, the empirical studies emanating from the literature scoping review suggested that NPs are able to provide 67–93% of all primary care services, yet, based on limited evidence. Conclusions NPs are a rapidly growing workforce with high levels of advanced practice potential in primary care. Workforce monitoring based on accurate data is critical to inform educational capacity

  14. Clinical and Laboratory Responses of Cross-Country Skiing for a 24-H World Record: Case Report.

    PubMed

    Niemelä, Markus; Juvonen, Jukka; Kangastupa, Päivikki; Niemelä, Onni; Juvonen, Tatu

    2015-12-01

    The physiological consequences of ultra-endurance cross-country skiing in cold conditions are poorly known. We report here clinical, echocardiographic and laboratory findings from a 41-y old male elite skier in a world record trial for 24-h skiing. The athlete completed a total of 406.8 km outdoors with the temperature ranging between -24°C and -5°C during the 24-h period. Post exercise, notable increases from baseline values were observed in myoglobin (50-fold), creatinine kinase (30-fold) and proBNP (6-fold), whereas troponin T or troponin I levels remained unchanged. At baseline, echocardiographic findings showed cardiac hypertrophy and after skiing, a 5% reduction of left-ventricular end-diastolic dimension. Increases in markers of kidney (creatinine) and liver function (alanine aminotransferase), serum uric acid, C-reactive protein and white blood cell counts were also noted. In addition, electrolyte disturbances including hyponatremia, hypophosphatemia and hypocalcaemia were noted during the follow-up. The data indicates that a prolonged period of high-intensity skiing leads to muscle, heart and kidney affection and activation of inflammation even in an experienced elite skier. The observed health effects underscore the need for strict medical surveillance of participants in extreme sports with long duration. Key pointsAn elite athlete was able to ski over 400 km during 24 hours with an outdoor temperature ranging between -5 °C and -24 °C.Several postrace abnormalities occurred in biomarkers of muscle, heart, kidney, liver and inflammation status.Serum troponins, specific markers of myocardial cell damage, remained stable.The report supports careful medical surveillance of participants in extreme sports with long duration.

  15. Assessment of Heart Rate Variability Thresholds from Incremental Treadmill Tests in Five Cross-Country Skiing Techniques

    PubMed Central

    Mendia-Iztueta, Ibai; Monahan, Kristen

    2016-01-01

    The assessment of heart rate variability (HRV) thresholds (HRVTs) as an alternative of Ventilatory thresholds (VTs) is a relatively new approach with increasing popularity which has not been conducted in cross-country (XC) skiing yet. The main purpose of the present study was to assess HRVTs in the five main XC skiing-related techniques, double poling (DP), diagonal striding (DS), Nordic walking (NW), V1 skating (V1), and V2 skating (V2).Ten competitive skiers completed these incremental treadmill tests until exhaustion with a minimum of one to two recovery days in between each test. Ventilatory gases, HRV and poling frequencies were measured. The first HRV threshold (HRVT1) was assessed using two time-domain analysis methods, and the second HRV threshold (HRVT2) was assessed using two non-time varying frequency-domain analysis methods. HRVT1 was assessed by plotting the mean successive difference (MSD) and standard deviation (SD) of normalized R-R intervals to workload. HRVT1 was assessed by plotting high frequency power (HFP) and the HFP relative to respiratory sinus arrhythmia (HFPRSA) with workload. HRVTs were named after their methods (HRVT1-SD; HRVT1-MSD; HRVT2-HFP; HRVT2-HFP-RSA). The results showed that the only cases where the proposed HRVTs were good assessors of VTs were the HRVT1-SD of the DS test, the HRVT1-MSD of the DS and V2 tests, and the HRVT2-HFP-RSA of the NW test. The lack of a wider success of the assessment of HRVTs was reasoned to be mostly due to the high entrainment between the breathing and poling frequencies. As secondary finding, a novel Cardiolocomotor coupling mode was observed in the NW test. This new Cardiolocoomtor coupling mode corresponded to the whole bilateral poling cycle instead of corresponding to each poling action as it was reported to the date by the existing literature. PMID:26727112

  16. Automatic classification of the sub-techniques (gears) used in cross-country ski skating employing a mobile phone.

    PubMed

    Stöggl, Thomas; Holst, Anders; Jonasson, Arndt; Andersson, Erik; Wunsch, Tobias; Norström, Christer; Holmberg, Hans-Christer

    2014-10-31

    The purpose of the current study was to develop and validate an automatic algorithm for classification of cross-country (XC) ski-skating gears (G) using Smartphone accelerometer data. Eleven XC skiers (seven men, four women) with regional-to-international levels of performance carried out roller skiing trials on a treadmill using fixed gears (G2left, G2right, G3, G4left, G4right) and a 950-m trial using different speeds and inclines, applying gears and sides as they normally would. Gear classification by the Smartphone (on the chest) and based on video recordings were compared. Formachine-learning, a collective database was compared to individual data. The Smartphone application identified the trials with fixed gears correctly in all cases. In the 950-m trial, participants executed 140 ± 22 cycles as assessed by video analysis, with the automatic Smartphone application giving a similar value. Based on collective data, gears were identified correctly 86.0% ± 8.9% of the time, a value that rose to 90.3% ± 4.1% (P < 0.01) with machine learning from individual data. Classification was most often incorrect during transition between gears, especially to or from G3. Identification was most often correct for skiers who made relatively few transitions between gears. The accuracy of the automatic procedure for identifying G2left, G2right, G3, G4left and G4right was 96%, 90%, 81%, 88% and 94%, respectively. The algorithm identified gears correctly 100% of the time when a single gear was used and 90% of the time when different gears were employed during a variable protocol. This algorithm could be improved with respect to identification of transitions between gears or the side employed within a given gear.

  17. Assessment of Heart Rate Variability Thresholds from Incremental Treadmill Tests in Five Cross-Country Skiing Techniques.

    PubMed

    Mendia-Iztueta, Ibai; Monahan, Kristen; Kyröläinen, Heikki; Hynynen, Esa

    2016-01-01

    The assessment of heart rate variability (HRV) thresholds (HRVTs) as an alternative of Ventilatory thresholds (VTs) is a relatively new approach with increasing popularity which has not been conducted in cross-country (XC) skiing yet. The main purpose of the present study was to assess HRVTs in the five main XC skiing-related techniques, double poling (DP), diagonal striding (DS), Nordic walking (NW), V1 skating (V1), and V2 skating (V2).Ten competitive skiers completed these incremental treadmill tests until exhaustion with a minimum of one to two recovery days in between each test. Ventilatory gases, HRV and poling frequencies were measured. The first HRV threshold (HRVT1) was assessed using two time-domain analysis methods, and the second HRV threshold (HRVT2) was assessed using two non-time varying frequency-domain analysis methods. HRVT1 was assessed by plotting the mean successive difference (MSD) and standard deviation (SD) of normalized R-R intervals to workload. HRVT1 was assessed by plotting high frequency power (HFP) and the HFP relative to respiratory sinus arrhythmia (HFPRSA) with workload. HRVTs were named after their methods (HRVT1-SD; HRVT1-MSD; HRVT2-HFP; HRVT2-HFP-RSA). The results showed that the only cases where the proposed HRVTs were good assessors of VTs were the HRVT1-SD of the DS test, the HRVT1-MSD of the DS and V2 tests, and the HRVT2-HFP-RSA of the NW test. The lack of a wider success of the assessment of HRVTs was reasoned to be mostly due to the high entrainment between the breathing and poling frequencies. As secondary finding, a novel Cardiolocomotor coupling mode was observed in the NW test. This new Cardiolocoomtor coupling mode corresponded to the whole bilateral poling cycle instead of corresponding to each poling action as it was reported to the date by the existing literature.

  18. Clinical and Laboratory Responses of Cross-Country Skiing for a 24-H World Record: Case Report

    PubMed Central

    Niemelä, Markus; Juvonen, Jukka; Kangastupa, Päivikki; Niemelä, Onni; Juvonen, Tatu

    2015-01-01

    The physiological consequences of ultra-endurance cross-country skiing in cold conditions are poorly known. We report here clinical, echocardiographic and laboratory findings from a 41-y old male elite skier in a world record trial for 24-h skiing. The athlete completed a total of 406.8 km outdoors with the temperature ranging between -24°C and –5°C during the 24-h period. Post exercise, notable increases from baseline values were observed in myoglobin (50-fold), creatinine kinase (30-fold) and proBNP (6-fold), whereas troponin T or troponin I levels remained unchanged. At baseline, echocardiographic findings showed cardiac hypertrophy and after skiing, a 5% reduction of left-ventricular end-diastolic dimension. Increases in markers of kidney (creatinine) and liver function (alanine aminotransferase), serum uric acid, C-reactive protein and white blood cell counts were also noted. In addition, electrolyte disturbances including hyponatremia, hypophosphatemia and hypocalcaemia were noted during the follow-up. The data indicates that a prolonged period of high-intensity skiing leads to muscle, heart and kidney affection and activation of inflammation even in an experienced elite skier. The observed health effects underscore the need for strict medical surveillance of participants in extreme sports with long duration. Key points An elite athlete was able to ski over 400 km during 24 hours with an outdoor temperature ranging between –5 °C and –24 °C. Several postrace abnormalities occurred in biomarkers of muscle, heart, kidney, liver and inflammation status. Serum troponins, specific markers of myocardial cell damage, remained stable. The report supports careful medical surveillance of participants in extreme sports with long duration. PMID:26664265

  19. Alterations in aerobic energy expenditure and neuromuscular function during a simulated cross-country skiathlon with the skating technique.

    PubMed

    Fabre, Nicolas; Mourot, Laurent; Zoppirolli, Chiara; Andersson, Erik; Willis, Sarah J; Holmberg, Hans-Christer

    2015-04-01

    Here, we tested the hypothesis that aerobic energy expenditure (AEE) is higher during a simulated 6-km (2 loops of 3-km each) "skiathlon" than during skating only on a treadmill and attempted to link any such increase to biomechanical and neuromuscular responses. Six elite male cross-country skiers performed two pre-testing time-trials (TT) to determine their best performances and to choose an appropriate submaximal speed for collection of physiological, biomechanical and neuromuscular data during two experimental sessions (exp). Each skier used, in randomized order, either the classical (CL) or skating technique (SK) for the first 3-km loop, followed by transition to the skating technique for the second 3-km loop. Respiratory parameters were recorded continuously. The EMG activity of the triceps brachii (TBr) and vastus lateralis (VLa) muscles during isometric contractions performed when the skiers were stationary (i.e., just before the first loop, during the transition, and after the second loop); their corresponding activity during dynamic contractions; and pole and plantar forces during the second loop were recorded. During the second 3-km of the TT, skating speed was significantly higher for the SK-SK than CL-SK. During this second loop, AEE was also higher (+1.5%) for CL-SKexp than SK-SKexp, in association with higher VLa EMG activity during both isometric and dynamic contractions, despite no differences in plantar or pole forces, poling times or cycle rates. Although the underlying mechanism remains unclear, during a skiathlon, the transition between the sections of classical skiing and skating alters skating performance (i.e., skiing speed), AEE and neuromuscular function.

  20. The influence of training and mental skills preparation on injury incidence and performance in marathon runners.

    PubMed

    Hamstra-Wright, Karrie L; Coumbe-Lilley, John E; Kim, Hajwa; McFarland, Jose A; Huxel Bliven, Kellie C

    2013-10-01

    There has been a considerable increase in the number of participants running marathons over the past several years. The 26.2-mile race requires physical and mental stamina to successfully complete it. However, studies have not investigated how running and mental skills preparation influence injury and performance. The purpose of our study was to describe the training and mental skills preparation of a typical group of runners as they began a marathon training program, assess the influence of training and mental skills preparation on injury incidence, and examine how training and mental skills preparation influence marathon performance. Healthy adults (N = 1,957) participating in an 18-week training program for a fall 2011 marathon were recruited for the study. One hundred twenty-five runners enrolled and received 4 surveys: pretraining, 6 weeks, 12 weeks, posttraining. The pretraining survey asked training and mental skills preparation questions. The 6- and 12-week surveys asked about injury incidence. The posttraining survey asked about injury incidence and marathon performance. Tempo runs during training preparation had a significant positive relationship to injury incidence in the 6-week survey (ρ[93] = 0.26, p = 0.01). The runners who reported incorporating tempo and interval runs, running more miles per week, and running more days per week in their training preparation ran significantly faster than did those reporting less tempo and interval runs, miles per week, and days per week (p ≤ 0.05). Mental skills preparation did not influence injury incidence or marathon performance. To prevent injury, and maximize performance, while marathon training, it is important that coaches and runners ensure that a solid foundation of running fitness and experience exists, followed by gradually building volume, and then strategically incorporating runs of various speeds and distances.

  1. Sex differences in elite swimming with advanced age are less than marathon running.

    PubMed

    Senefeld, J; Joyner, M J; Stevens, A; Hunter, S K

    2016-01-01

    The sex difference in marathon performance increases with finishing place and age of the runner but whether this occurs among swimmers is unknown. The purpose was to compare sex differences in swimming velocity across world record place (1st-10th), age group (25-89 years), and event distance. We also compared sex differences between freestyle swimming and marathon running. The world's top 10 swimming times of both sexes for World Championship freestyle stroke, backstroke, breaststroke, and butterfly events and the world's top 10 marathon times in 5-year age groups were obtained. Men were faster than women for freestyle (12.4 ± 4.2%), backstroke (12.8 ± 3.0%), and breaststroke (14.5 ± 3.2%), with the greatest sex differences for butterfly (16.7 ± 5.5%). The sex difference in swimming velocity increased across world record place for freestyle (P < 0.001), breaststroke, and butterfly for all age groups and distances (P < 0.001) because of a greater relative drop-off between first and 10th place for women. The sex difference in marathon running increased with the world record place and the sex difference for marathon running was greater than for swimming (P < 0.001). The sex difference in swimming increased with world record place and age, but was less than for marathon running. Collectively, these results suggest more depth in women's swimming than marathon running. PMID:25648250

  2. Effects of Sprint versus High-Intensity Aerobic Interval Training on Cross-Country Mountain Biking Performance: A Randomized Controlled Trial

    PubMed Central

    Inoue, Allan; Impellizzeri, Franco M.; Pires, Flávio O.; Pompeu, Fernando A. M. S.; Deslandes, Andrea C.; Santos, Tony M.

    2016-01-01

    Objectives The current study compared the effects of high-intensity aerobic training (HIT) and sprint interval training (SIT) on mountain biking (MTB) race simulation performance and physiological variables, including peak power output (PPO), lactate threshold (LT) and onset of blood lactate accumulation (OBLA). Methods Sixteen mountain bikers (mean ± SD: age 32.1 ± 6.4 yr, body mass 69.2 ± 5.3 kg and VO2max 63.4 ± 4.5 mL∙kg-1∙min-1) completed graded exercise and MTB performance tests before and after six weeks of training. The HIT (7–10 x [4–6 min—highest sustainable intensity / 4–6 min—CR100 10–15]) and SIT (8–12 x [30 s—all-out intensity / 4 min—CR100 10–15]) protocols were included in the participants’ regular training programs three times per week. Results Post-training analysis showed no significant differences between training modalities (HIT vs. SIT) in body mass, PPO, LT or OBLA (p = 0.30 to 0.94). The Cohen’s d effect size (ES) showed trivial to small effects on group factor (p = 0.00 to 0.56). The interaction between MTB race time and training modality was almost significant (p = 0.08), with a smaller ES in HIT vs. SIT training (ES = -0.43). A time main effect (pre- vs. post-phases) was observed in MTB race performance and in several physiological variables (p = 0.001 to 0.046). Co-variance analysis revealed that the HIT (p = 0.043) group had significantly better MTB race performance measures than the SIT group. Furthermore, magnitude-based inferences showed HIT to be of likely greater benefit (83.5%) with a lower probability of harmful effects (0.8%) compared to SIT. Conclusion The results of the current study suggest that six weeks of either HIT or SIT may be effective at increasing MTB race performance; however, HIT may be a preferable strategy. Trial Registration ClinicalTrials.gov NCT01944865 PMID:26789124

  3. Certain surfactants significantly enhance the activity of antibiotics in the mouse model of MTB and drug resistant MTB infection and effectively remove the bacteria from a pulmonary cavity in human ex-vivo study.

    PubMed

    Risin, Semyon A; Hunter, Robert L; Kobak, Mikhail; Ariel, Boris; Vishnevsky, Boris; Erokhin, Vladislav; Demikhova, Olga; Bocharova, Irina; Stoops, James K

    2014-01-01

    Surfactants have the potential to overcome natural resistance of MTB to antibiotics which is mediated by barriers that impede the penetration of drugs to their targets. A major component of this barrier is trehalose dimycolate (TDM) which surrounds the bacteria with a thick lipid shield. In this study dodecyl maltoside (DDM) was evaluated for this purpose. This surfactant is an excellent cellular permeabilizing agent with associated low toxicity. The administration of the surfactant as an aerosol into the lungs of the infected mice achieved a 5-10 times enhancement of the isoniazid (INH) treatment gauged by the reduction of the colony forming units. This study also established proof of principle that surfactants alone applied as an aerosol can reduce the bacteria count in lungs infected with MTB. The potential of the surfactant in the therapy of human cavitary TB was also investigated using a surgically removed lung from a patient with extreme drug resistant MTB (XDR-TB). A cavity in this lung was flushed with DDM solution ex-vivo. The procedure readily removed the bacteria, excessive amounts of TDM and necrotic tissue from the cavity. These studies demonstrate that DDM can disrupt the layers of TDM and free embedded MTB and, consequently, surfactants have promise as a proficient modality for the treatment of pulmonary MTB.

  4. 78 FR 10128 - Expansion/Reorganization of Foreign-Trade Subzone 70T; Marathon Petroleum Company LP; Detroit, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    ... Marathon Petroleum Company LP refinery in Detroit, Michigan. (B-42-2012, docketed 6/1/2012); Whereas, notice inviting public comment has been given in the Federal Register (77 FR 33716-33717) and the... Foreign-Trade Zones Board Expansion/Reorganization of Foreign-Trade Subzone 70T; Marathon...

  5. 76 FR 54764 - Marathon Power LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Marathon Power LLC; Supplemental Notice That Initial Market-Based Rate...-referenced proceeding of Marathon Power LLC's application for market-based rate authority, with...

  6. The Use of a Modified Marathon in Conjunction with Group Counseling in Short-term Treatment of Alcoholics

    ERIC Educational Resources Information Center

    Gazda, G. M.; And Others

    1971-01-01

    Two conclusions drawn from the application of the modified marathon to a short term treatment center were that the modified marathon had the advantages of holding" alcoholics for treatment once they were sober and it enhanced the quality of typical group counseling and therapy treatment. (Author)

  7. The Effects of 16 Hour Long Marathon Groups on the Ways that Female Drug Users Perceive Women.

    ERIC Educational Resources Information Center

    Page, Richard C.

    1984-01-01

    Evaluated the effectiveness of three 16-hour-long unstructured marathon groups composed of female illicit drug users in a woman's prison (N=78), using evaluative adjective pairs of the semantic differential concept Women. Marathon groups rated women as more successful and more pleasurable than did controls. (JAC)

  8. Effects of training and anthropometric factors on marathon and 100 km ultramarathon race performance

    PubMed Central

    Tanda, Giovanni; Knechtle, Beat

    2015-01-01

    Background Marathon (42 km) and 100 km ultramarathon races are increasing in popularity. The aim of the present study was to investigate the potential associations of anthropometric and training variables with performance in these long-distance running competitions. Methods Training and anthropometric data from a large cohort of marathoners and 100 km ultramarathoners provided the basis of this work. Correlations between training and anthropometric indices of subjects and race performance were assessed using bivariate and multiple regression analyses. Results A combination of volume and intensity in training was found to be suitable for prediction of marathon and 100 km ultramarathon race pace. The relative role played by these two variables was different, in that training volume was more important than training pace for the prediction of 100 km ultramarathon performance, while the opposite was found for marathon performance. Anthropometric characteristics in terms of body fat percentage negatively affected 42 km and 100 km race performance. However, when this factor was relatively low (ie, less than 15% body fat), the performance of 42 km and 100 km races could be predicted solely on the basis of training indices. Conclusion Mean weekly training distance run and mean training pace were key predictor variables for both marathon and 100 km ultramarathon race performance. Predictive correlations for race performance are provided for runners with a relatively low body fat percentage. PMID:25995653

  9. Plantar Pressures During Long Distance Running: An Investigation of 10 Marathon Runners

    PubMed Central

    Hohmann, Erik; Reaburn, Peter; Tetsworth, Kevin; Imhoff, Andreas

    2016-01-01

    The objective of this study was to record plantar pressures using an in-shoe measuring system before, during, and after a marathon run in ten experienced long-distance runners with a mean age of 37.7 ± 11.5 years. Peak and mean plantar pressures were recorded before, after, and every three km during a marathon race. There were no significant changes over time in peak and mean plantar pressures for either the dominant or non-dominant foot. There were significant between foot peak and mean plantar pressure differences for the total foot (p = 0.0001), forefoot (p = 0.0001), midfoot (p = 0.02 resp. p = 0.006), hindfoot (p = 0.0001), first ray (p = 0.01 resp. p = 0.0001) and MTP (p = 0.05 resp. p = 0.0001). Long-distance runners do not demonstrate significant changes in mean or peak plantar foot pressures over the distance of a marathon race. However, athletes consistently favoured their dominant extremity, applying significantly higher plantar pressures through their dominant foot over the entire marathon distance. Key points Fatigue does not increase foot pressures Every runner has a dominant foot where pressures are higher and that he/she favours Foot pressures do not increase over the distance of a marathon run PMID:27274662

  10. The effect of HIV coinfection, HAART and TB treatment on cytokine/chemokine responses to Mycobacterium tuberculosis (Mtb) antigens in active TB patients and latently Mtb infected individuals.

    PubMed

    Kassa, Desta; de Jager, Wilco; Gebremichael, Gebremedhin; Alemayehu, Yodit; Ran, Leonie; Fransen, Justin; Wolday, Dawit; Messele, Tsehaynesh; Tegbaru, Belete; Ottenhoff, Tom H M; van Baarle, Debbie

    2016-01-01

    Identification of Mtb specific induced cytokine/chemokine host biomarkers could assist in developing novel diagnostic, prognostic and therapeutic tools for TB. Levels of IFN-γ, IL-2, IL-17, IL-10, IP-10 and MIP-1α were measured in supernatants of whole blood stimulated with Mtb specific fusion protein ESAT-6/CFP-10 using xMAP technology. The study groups were HIV positive TB patients (HIV(+)TB(+)), HIV negative TB patients (HIV(-)TB(+)), HIV positive tuberculin skin test positive (TST+) (HIV(+)TST(+)), HIV negative TST+ (HIV(-)TST(+)), and HIV(-)TST(-) individuals. Compared to HIV(-)TST(-), latent TB infection led to increased levels of IP-10, IFN-γ and IL-17, while levels of IL-2 and IP-10 were increased with active TB. Levels of IFN-γ, IL-17, MIP-1α, and IL-10 were increased in HIV(-)TST(+) individuals compared to HIV(-)TB(+) patients. HIV coinfection decreased the level of IFN-γ, IL-17, IP-10 and IL-2. After six months (M6) of anti-TB treatment (ATT) in HIV(-)TB(+) patients, IFN-γ, IL-10, and MIP-1α levels normalized. After M6 and M18 of ATT plus HAART in HIV(+)TB(+) patients, levels of MIP-1α and IL-10 normalized, while this was not the case for IFN-γ, IL-2, IL-17, and IP-10 levels. In HIV(+)TST(+) patients on HAART, levels of IFN-γ, IL-17, IL-10 and MIP-1α normalized, while no change in the levels of IL-2 and IP-10 were observed. In conclusion, the simultaneous measurement of IFN-γ, IL-17 and IP-10 may assist in diagnosing LTBI; IL-2 and IP-10 may assist in diagnosing active TB; while IFN-γ, IL-17, MIP-1α, and IL-10 levels could help to discriminate LTBI and active TB. In addition, IL-10 and MIP-1α levels could help to monitor responses to TB treatment and HAART.

  11. COBAS® TaqMan® MTB, smear positivity grade and MGIT culture; correlation analyses of three methods for bacillary quantification.

    PubMed

    Chikamatsu, Kinuyo; Aono, Akio; Kato, Tomoko; Takaki, Akiko; Yamada, Hiroyuki; Sasaki, Yuka; Izumi, Kiyohiko; Yi, Lina; Mitarai, Satoshi

    2016-01-01

    We investigated the correlation between the cycle threshold (Ct) value of the COBAS(®) TaqMan(®) MTB (TaqMan MTB), the mycobacterial smear positivity grade, and the time to detection (TTD) in the Mycobacteria Growth Indicator Tube (MGIT) for quantification of Mycobacterium tuberculosis (MTB). For 57 sputum samples, significant correlations were observed between the Ct value, the smear positivity grade, and the MGIT TTD (Spearman's rank correlation coefficient: r(s) = -0.940, P < 0.001 and Pearson's correlation coefficient: r(p) = 0.737, P < 0.001). In addition, a correlation was observed between the number of bacteria estimated based on the smear positivity grade and the number of MTB bacilli calculated by the Ct value (r(s) = 0.930, P < 0.001). This study has demonstrated the possible estimation of the smear positivity grade and MGIT TTD using the Ct value of TaqMan MTB, which is based on a real-time PCR system, for diagnostic samples.

  12. Effects of intensity and duration in aerobic high-intensity interval training in highly trained junior cross-country skiers.

    PubMed

    Sandbakk, Øyvind; Sandbakk, Silvana B; Ettema, Gertjan; Welde, Boye

    2013-07-01

    The purpose of this study was to test whether a long duration of aerobic high-intensity interval training is more effective than shorter intervals at a higher intensity in highly trained endurance athletes. The sample comprised of 12 male and 9 female, national-level, junior cross-country skiers (age, 17.5 ± 0.4 years, maximal oxygen uptake (V[Combining Dot Above]O2max): 67.4 ± 7.7 ml min kg), who performed 8-week baseline and 8-week intervention training periods on dry land. During the intervention period, a short-interval group (SIG, n = 7) added 2 weekly sessions with short duration intervals (2- to 4-minute bouts, total duration of 15-20 minutes), a long-interval group (LIG; n = 7) added 2 weekly sessions with long duration intervals (5- to 10-minute bouts, total duration of 40-45 minutes). The interval sessions were performed with the athletes' maximal sustainable intensity. A control group (CG; n = 7) added 2 weekly sessions with low-intensity endurance training at 65-74% of maximal heart rate. Before and after the intervention period, the skiers were tested for time-trial performance on 12-km roller-ski skating and 7-km hill run. V[Combining Dot Above]O2max and oxygen uptake at the ventilatory threshold (V[Combining Dot Above]O2VT) were measured during treadmill running. After the intervention training period, the LIG-improved 12-km roller ski, 7-km hill run, V[Combining Dot Above]O2max, and V[Combining Dot Above]O2VT by 6.8 ± 4.0%, 4.8 ± 2.6%, 3.7 ± 1.6%, and 5.8 ± 3.3%, respectively, from pre- to posttesting, and improved both performance tests and V[Combining Dot Above]O2VT when compared with the SIG and the CG (all p < 0.05). The SIG improved V[Combining Dot Above]O2max by 3.5 ± 3.2% from pre- to posttesting (p < 0.05), whereas the CG remained unchanged. As hypothesized, a long duration of aerobic high-intensity interval training improved endurance performance and oxygen uptake at the ventilatory threshold more than shorter intervals at a higher

  13. A systematic assessment of the current capacity to act in nutrition in West Africa: cross-country similarities and differences

    PubMed Central

    Sodjinou, Roger; Bosu, William K.; Fanou, Nadia; Déart, Lucie; Kupka, Roland; Tchibindat, Félicité; Baker, Shawn

    2014-01-01

    Background Although it is widely accepted that lack of capacity is one of the barriers to scaling up nutrition in West Africa, there is a paucity of information about what capacities exist and the capacities that need to be developed to accelerate progress toward improved nutrition outcomes in the region. Objective To systematically assess the current capacity to act in nutrition in the West Africa region and explore cross-country similarities and differences. Design Data were collected from 13 West African countries through interviews with government officials, key development partners, tertiary-level training institutions, and health professional schools. The assessment was based on a conceptual framework of four interdependent levels (tools; skills; staff and infrastructure; and structures, systems and roles). In each of the surveyed countries, we assessed capacity assets and gaps at individual, organizational, and systemic levels. Results Important similarities and differences in capacity assets and gaps emerged across all the surveyed countries. There was strong momentum to improve nutrition in nearly all the surveyed countries. Most of the countries had a set of policies on nutrition in place and had set up multisectoral, multi-stakeholder platforms to coordinate nutrition activities, although much remained to be done to improve the effectiveness of these platforms. Many initiatives aimed to reduce undernutrition were ongoing in the region, but there did not seem to be clear coordination between them. Insufficient financial resources to implement nutrition activities were a major problem in all countries. The bulk of financial allocations for nutrition was provided by development partners, even though some countries, such as Niger, Nigeria, and Senegal, had a national budget line for nutrition. Sporadic stock-outs of nutrition supplies were reported in most of the countries as a result of a weak logistic and supply chain system. They also had a critical

  14. Determinants of a simulated cross-country skiing sprint competition using V2 skating technique on roller skis.

    PubMed

    Mikkola, Jussi; Laaksonen, Marko; Holmberg, Hans-Christer; Vesterinen, Ville; Nummela, Ari

    2010-04-01

    The present study investigated the performance-predicting factors of a simulated cross-country (XC) skiing sprint competition on roller skis, on a slow surface. Sixteen elite male XC skiers performed a simulated sprint competition (4 x 850 m heat with a 20-minute recovery) using V2 skating technique on an indoor tartan track. Heat velocities, oxygen consumption, and peak lactate were measured during or after the heats. Maximal skiing velocity was measured by performing a 30-m speed test. Explosive and maximal force production in the upper body was determined by bench press (BP). Subjects also performed maximal anaerobic skiing test (MAST) and the 2 x 2-km double poling (DP) test. The maximal velocity of MAST (VMAST) and velocities at 3 (V3), 5 (V5), 7 (V7) mmol.L lactate levels in MAST were determined. In the 2 x 2-km test, DP economy (VO2SUBDP) and maximal 2-km DP velocity (VDP2KM) were determined. The best single performance-predicting factors for the sprint performance were VDP2KM (r = 0.73, p < 0.01), V7 (r = 0.70, p < 0.01), and VO2SUBDP (r = -0.70, p < 0.01). Faster skiers in sprint simulation had a higher absolute VO2 (L.min) (p < 0.05-0.01) during sprint heats, and higher anaerobic skiing power (VMAST, p < 0.05) and better anaerobic skiing economy (V3, V5, V7, p < 0.05-0.001) than slower skiers. Faster skiers were also stronger in BP, with regard to both absolute (p < 0.01) and relative (p < 0.05) values. In addition, anaerobic characteristics seem to be of importance at the beginning of the XC skiing sprint competition, whereas the aerobic characteristics become more important as the XC skiing sprint competition progressed. This study indicates that sprint skiers should emphasize sport-specific upper body training, and training skiing economy at high speeds.

  15. Impact of the Boston Marathon Bombing and Its Aftermath on Refugees and Survivors of Torture.

    PubMed

    Piwowarczyk, Linda; Rous, Dana; Mancuso, Anna; Flinton, Kathleen; Hastings, Erica; Forbush, Leigh; Shepherd, Amy

    2016-08-01

    On April 15, 2013, Boston residents and guests gathered for the Boston Marathon. Two explosives at the finish line killed three people and injured hundreds of others. As part of our clinical encounters, patients of the Boston Center for Refugee Health & Human Rights were asked about the marathon bombing. We were concerned about the high level of armed security as many of our patients had been detained in their countries of origin. Eighty patients seen between April 16 and July 7, 2013 were asked about their experience of the Boston Marathon bombing and its aftermath. A retrospective chart review was undertaken and data analyzed using Atlas.ti & SPSS. Approximately 86 % of those interviewed were reminded of their past trauma. The following themes emerged: triggering and trauma related symptoms, content specific cognitive schemas, recognition of the universality of violence, fears of discrimination, issues surrounding safety, and specific concerns of Muslims. PMID:26289501

  16. Impact of the Boston Marathon Bombing and Its Aftermath on Refugees and Survivors of Torture.

    PubMed

    Piwowarczyk, Linda; Rous, Dana; Mancuso, Anna; Flinton, Kathleen; Hastings, Erica; Forbush, Leigh; Shepherd, Amy

    2016-08-01

    On April 15, 2013, Boston residents and guests gathered for the Boston Marathon. Two explosives at the finish line killed three people and injured hundreds of others. As part of our clinical encounters, patients of the Boston Center for Refugee Health & Human Rights were asked about the marathon bombing. We were concerned about the high level of armed security as many of our patients had been detained in their countries of origin. Eighty patients seen between April 16 and July 7, 2013 were asked about their experience of the Boston Marathon bombing and its aftermath. A retrospective chart review was undertaken and data analyzed using Atlas.ti & SPSS. Approximately 86 % of those interviewed were reminded of their past trauma. The following themes emerged: triggering and trauma related symptoms, content specific cognitive schemas, recognition of the universality of violence, fears of discrimination, issues surrounding safety, and specific concerns of Muslims.

  17. Imaging of lower extremity trauma from Boston Marathon bombing.

    PubMed

    Konwinski, Ryan R; Singh, Ajay; Soto, Jorge

    2016-10-01

    The goal of this study is to describe the imaging features of lower extremity blast injuries in patients encountered in the radiology departments from the Boston Marathon bombings. A total of 115 patients presented to four acute care hospitals on April 15, 2013, 43 of whom presented with lower extremity injuries and were included in this study. The imaging findings of primary, secondary, tertiary, and quaternary blast injuries were evaluated. Forty-one of 43 patients sustained secondary blast injuries to the lower extremities with 31 patients (70 %) having retained shrapnel, seven patients (16 %) having soft tissue lacerations without retained shrapnel, and ten patients (23 %) having lower extremity amputation (7 % double amputees). Eight of these patients (20 %) had lower extremity fractures, and five patients (12 %) had vascular injuries. Two of the 43 patients (5 %) had only tertiary injuries, and five of 43 patients (12 %) were noted to have lower extremity burns, consistent with quaternary blast injury. No primary blast injury occurred in the lower extremities. A vast majority of lower extremity injuries were from secondary blast injury, most commonly from retained shrapnel in 70 % of patients and 23 % of patients sustaining lower extremity amputation. Retained shrapnel in the lower extremity was most commonly ball bearings and pressure cooker fragments, and most injuries affected the leg, followed by the thigh and foot. PMID:27272899

  18. Fluoride concentrations in a crystalline bedrock aquifer Marathon County, Wisconsin

    NASA Astrophysics Data System (ADS)

    Ozsvath, David L.

    2006-05-01

    Water samples from 2,789 private water-supply wells in Marathon County, Wisconsin reveal that fluoride concentrations in the crystalline bedrock range from <0.01 to 7.60 mg/L, with 0.6% of the values exceeding the Environmental Protection Agency’s (EPA’s) maximum contaminant level of 4 mg/L, and 8.6% exceeding the EPA’s secondary maximum contaminant level of 2.0 mg/L. Roughly a quarter of the wells contain dissolve fluoride within the range considered optimal for human health (between 0.5 and 1.5 mg/L), whereas 63.3% fall below 0.5 mg/L. Consistent with studies conducted in other regions, felsic rocks have significantly higher fluoride concentrations than mafic and metasedimentary rocks. Syenites yield the most fluoriferous groundwaters, but the highest median concentration occurs in a sodium-plagioclase granite. A relationship between plagioclase composition and fluoride concentrations suggests that dissolved fluoride levels are controlled by fluorite solubility and that higher fluoride concentrations are found in soft, sodium-rich groundwater.

  19. Low energy availability in the marathon and other endurance sports.

    PubMed

    Loucks, Anne B

    2007-01-01

    Energy availability is the amount of dietary energy remaining after exercise training for all other metabolic processes. Excessively low energy availability impairs reproductive and skeletal health, although genetics and age may alter an individual's initial conditions and sensitivity when low energy availability is imposed. Many marathon runners and other endurance athletes reduce energy availability either (i) intentionally to modify body size and composition for improving performance; (ii) compulsively in a psychopathological pattern of disordered eating; or (iii) inadvertently because there is no strong biological drive to match energy intake to activity-induced energy expenditure. Inadvertent low energy availability is more extreme when consuming a low fat, high carbohydrate diet. Low energy availability, reproductive disorders, low bone mineral density and stress fractures are more common in female than male athletes. Functional menstrual disorders caused by low energy availability should be diagnosed by excluding diseases that also disrupt menstrual cycles. To determine energy availability (in units of kilocalories or kilojoules per kilogram of fat-free mass), athletes can record their diets and use diet analysis software to calculate energy intake, measure energy expenditure during exercise using a heart monitor and measure fat-free mass using a bioelectrical impedance body composition scale. All are commercially available at consumer prices.

  20. Imaging of lower extremity trauma from Boston Marathon bombing.

    PubMed

    Konwinski, Ryan R; Singh, Ajay; Soto, Jorge

    2016-10-01

    The goal of this study is to describe the imaging features of lower extremity blast injuries in patients encountered in the radiology departments from the Boston Marathon bombings. A total of 115 patients presented to four acute care hospitals on April 15, 2013, 43 of whom presented with lower extremity injuries and were included in this study. The imaging findings of primary, secondary, tertiary, and quaternary blast injuries were evaluated. Forty-one of 43 patients sustained secondary blast injuries to the lower extremities with 31 patients (70 %) having retained shrapnel, seven patients (16 %) having soft tissue lacerations without retained shrapnel, and ten patients (23 %) having lower extremity amputation (7 % double amputees). Eight of these patients (20 %) had lower extremity fractures, and five patients (12 %) had vascular injuries. Two of the 43 patients (5 %) had only tertiary injuries, and five of 43 patients (12 %) were noted to have lower extremity burns, consistent with quaternary blast injury. No primary blast injury occurred in the lower extremities. A vast majority of lower extremity injuries were from secondary blast injury, most commonly from retained shrapnel in 70 % of patients and 23 % of patients sustaining lower extremity amputation. Retained shrapnel in the lower extremity was most commonly ball bearings and pressure cooker fragments, and most injuries affected the leg, followed by the thigh and foot.

  1. Systematic review: Comparison of Xpert MTB/RIF, LAMP and SAT methods for the diagnosis of pulmonary tuberculosis.

    PubMed

    Yan, Liping; Xiao, Heping; Zhang, Qing

    2016-01-01

    Technological advances in nucleic acid amplification have led to breakthroughs in the early detection of PTB compared to traditional sputum smear tests. The sensitivity and specificity of loop-mediated isothermal amplification (LAMP), simultaneous amplification testing (SAT), and Xpert MTB/RIF for the diagnosis of pulmonary tuberculosis were evaluated. A critical review of previous studies of LAMP, SAT, and Xpert MTB/RIF for the diagnosis of pulmonary tuberculosis that used laboratory culturing as the reference method was carried out together with a meta-analysis. In 25 previous studies, the pooled sensitivity and specificity of the diagnosis of tuberculosis were 93% and 94% for LAMP, 96% and 88% for SAT, and 89% and 98% for Xpert MTB/RIF. The I(2) values for the pooled data were >80%, indicating significant heterogeneity. In the smear-positive subgroup analysis of LAMP, the sensitivity increased from 93% to 98% (I(2) = 2.6%), and specificity was 68% (I(2) = 38.4%). In the HIV-infected subgroup analysis of Xpert MTB/RIF, the pooled sensitivity and specificity were 79% (I(2) = 72.9%) and 99% (I(2) = 64.4%). In the HIV-negative subgroup analysis for Xpert MTB/RIF, the pooled sensitivity and specificity were 72% (I(2) = 49.6%) and 99% (I(2) = 64.5%). LAMP, SAT and Xpert MTB/RIF had comparably high levels of sensitivity and specificity for the diagnosis of tuberculosis. The diagnostic sensitivity and specificity of three methods were similar, with LAMP being highly sensitive for the diagnosis of smear-positive PTB. The cost effectiveness of LAMP and SAT make them particularly suitable tests for diagnosing PTB in developing countries. PMID:26786658

  2. Myosin Light Chain Kinase (MLCK) Gene Influences Exercise Induced Muscle Damage during a Competitive Marathon

    PubMed Central

    Valero, Marjorie; Lara, Beatriz; Salinero, Juan José; Gallo-Salazar, César; Areces, Francisco

    2016-01-01

    Myosin light chain kinase (MLCK) phosphorylates the regulatory light chain (RLC) of myosin producing increases in force development during skeletal muscle contraction. It has been suggested that MLCK gene polymorphisms might alter RLC phosphorylation thereby decreasing the ability to produce force and to resist strain during voluntary muscle contractions. Thus, the genetic variations in the MLCK gene might predispose some individuals to higher values of muscle damage during exercise, especially during endurance competitions. The aim of this investigation was to determine the influence of MLCK genetic variants on exercise-induced muscle damage produced during a marathon. Sixty-seven experienced runners competed in a marathon race. The MLCK genotype (C37885A) of these marathoners was determined. Before and after the race, a sample of venous blood was obtained to assess changes in serum myoglobin concentrations and leg muscle power changes were measured during a countermovement jump. Self-reported leg muscle pain and fatigue were determined by questionnaires. A total of 59 marathoners (88.1%) were CC homozygotes and 8 marathoners (11.9%) were CA heterozygotes. The two groups of participants completed the race with a similar time (228 ± 33 vs 234 ± 39 min; P = 0.30) and similar self-reported values for fatigue (15 ± 2 vs 16 ± 2 A.U.; P = 0.21) and lower-limb muscle pain (6.2 ± 1.7 vs 6.6 ± 1.8 cm; P = 0.29). However, CC marathoners presented higher serum myoglobin concentrations (739 ± 792 vs 348 ± 144 μg·mL-1; P = 0.03) and greater pre-to-post- race leg muscle power reduction (-32.7 ± 15.7 vs -21.2 ± 21.6%; P = 0.05) than CA marathoners. CA heterozygotes for MLCK C37885A might present higher exercise-induced muscle damage after a marathon competition than CC counterparts. PMID:27483374

  3. Myosin Light Chain Kinase (MLCK) Gene Influences Exercise Induced Muscle Damage during a Competitive Marathon.

    PubMed

    Del Coso, Juan; Valero, Marjorie; Lara, Beatriz; Salinero, Juan José; Gallo-Salazar, César; Areces, Francisco

    2016-01-01

    Myosin light chain kinase (MLCK) phosphorylates the regulatory light chain (RLC) of myosin producing increases in force development during skeletal muscle contraction. It has been suggested that MLCK gene polymorphisms might alter RLC phosphorylation thereby decreasing the ability to produce force and to resist strain during voluntary muscle contractions. Thus, the genetic variations in the MLCK gene might predispose some individuals to higher values of muscle damage during exercise, especially during endurance competitions. The aim of this investigation was to determine the influence of MLCK genetic variants on exercise-induced muscle damage produced during a marathon. Sixty-seven experienced runners competed in a marathon race. The MLCK genotype (C37885A) of these marathoners was determined. Before and after the race, a sample of venous blood was obtained to assess changes in serum myoglobin concentrations and leg muscle power changes were measured during a countermovement jump. Self-reported leg muscle pain and fatigue were determined by questionnaires. A total of 59 marathoners (88.1%) were CC homozygotes and 8 marathoners (11.9%) were CA heterozygotes. The two groups of participants completed the race with a similar time (228 ± 33 vs 234 ± 39 min; P = 0.30) and similar self-reported values for fatigue (15 ± 2 vs 16 ± 2 A.U.; P = 0.21) and lower-limb muscle pain (6.2 ± 1.7 vs 6.6 ± 1.8 cm; P = 0.29). However, CC marathoners presented higher serum myoglobin concentrations (739 ± 792 vs 348 ± 144 μg·mL-1; P = 0.03) and greater pre-to-post- race leg muscle power reduction (-32.7 ± 15.7 vs -21.2 ± 21.6%; P = 0.05) than CA marathoners. CA heterozygotes for MLCK C37885A might present higher exercise-induced muscle damage after a marathon competition than CC counterparts. PMID:27483374

  4. Selected scientific aspects of marathon racing. An update on fluid replacement, immune function, psychological factors and the gender difference.

    PubMed

    Sparling, P B; Nieman, D C; O'Connor, P J

    1993-02-01

    Four topics are addressed: fluid/fuel replacement during the marathon, marathoning and susceptibility to infection, psychological aspects of elite marathoners and the gender gap in marathon performance. Although these topics are diverse, they all relate to practical questions raised by coaches and athletes. Evidence from laboratory and field studies indicates that it is advisable for marathoners to consume 800 to 1000 L/h of sports drink providing 45 to 60 g/h of carbohydrate. It is strongly suggested to practice fluid consumption during training sessions as it is probable that tolerance to drinking during running is a trainable adaptation. Epidemiological and clinical research support the concept that marathon training and racing increase the runner's risk of upper respiratory tract infections because of negative changes in immune function. Susceptibility to infection may be reduced by proper nutrition, adequate sleep, appropriate recovery between vigorous workouts and minimal exposure to sick people during periods of heavy training and major races. Although psychological research in this area is still limited, evidence suggests that elite marathoners rely primarily on associative strategies during competition while judiciously dissociating in order to cope with pain. It is recommended that coaches and athletes interested in employing psychological interventions seek assistance from professionals well trained in the fields of both psychology and exercise science. Will women soon outrun men? Over the past 2 decades societal views and training practices of women distance runners have changed greatly, yet certain performance-related biological differences between men and women are unlikely to change.

  5. Performance characteristics of the new Abbott Real Time MTB assay for detection of Mycobacterium tuberculosis complex in respiratory specimens.

    PubMed

    Vinuesa, Víctor; Navarro, David; Poujois, Sandrine; Zaragoza, Susana; Borrás, Rafael

    2016-03-01

    The performance of the Abbott Real Time MTB assay for detection of Mycobacterium tuberculosis complex in respiratory specimens was evaluated using a standard culture as the reference. The overall concordance between both methods was 0.95. The assay displayed an excellent sensitivity (100% for smear-positive/92.3% for smear-negative specimens) and specificity (100%).

  6. The Use of Xpert MTB/Rif for Active Case Finding among TB Contacts in North West Province, South Africa.

    PubMed

    Lebina, Limakatso; Fuller, Nigel; Osoba, Tolu; Scott, Lesley; Motlhaoleng, Katlego; Rakgokong, Modiehi; Abraham, Pattamukkil; Variava, Ebrahim; Martinson, Neil Alexander

    2016-01-01

    Introduction. Tuberculosis is a major cause of morbidity and mortality especially in high HIV burden settings. Active case finding is one strategy to potentially reduce TB disease burden. Xpert MTB/Rif has recently been recommended for diagnosis of TB. Methods. Pragmatic randomized trial to compare diagnosis rate and turnaround time for laboratory testing for Xpert MTB/Rif with TB microscopy and culture in household contacts of patients recently diagnosed with TB. Results. 2464 household contacts enrolled into the study from 768 active TB index cases. 1068 (44%) were unable to give sputum, but 24 of these were already on TB treatment. 863 (53%) participants sputum samples were tested with smear and culture and 2.7% (23/863; CI: 1.62-3.78) were diagnosed with active TB. Xpert MTB/Rif was used in 515 (21%) participants; active TB was diagnosed in 1.6% (8/515; CI: 0.52-2.68). Discussion and Conclusions. Additional 31 cases were diagnosed with contact tracing of household members. When Xpert MTB/Rif is compared with culture, there is no significant difference in diagnostic yield. PMID:27493800

  7. Molecular Polymorphism in the MTA and MTB Mating Type Genes of Tetrahymena thermophila and Related Asexual Species.

    PubMed

    Booth, Laurie; Wolfe, Benjamin; Doerder, F Paul

    2015-01-01

    Each of the seven mating types of Tetrahymena thermophila is determined by a pair of large genes, MTA and MTB, whose expression peaks at early conjugation. Each protein consists of a mating-type specific domain and a common transmembrane domain. To assess variation in natural populations, regions of both domains from wild isolates expressing mating types V and VII were analyzed. Corresponding regions of amicronucleates incapable of mating also were examined. MTA and MTB showed high haplotype diversity, with greater sequence variation in MTB. Mating type VII was less variable than mating type V, suggesting more recent origin. No polymorphism distinguished between mat1- and mat2-like alleles encoding different arrays of mating types, nor did polymorphisms give evidence of population structure. MTA and MTB variants have different phylogenies, suggesting independent rather than concerted evolution, and are under weak purifying selection. Codon usage is less biased than for housekeeping genes, and reassigned glutamine encoding stop codons are preferentially used. Amicronucleate T. thermophila and closely related nsp15 and nsp25 have higher levels of nucleotide and amino acid substitution, consistent with cox1 distances. The results suggest that complete sequencing of mating type genes of wild isolates coupled with functional analysis will be informative.

  8. The Use of Xpert MTB/Rif for Active Case Finding among TB Contacts in North West Province, South Africa

    PubMed Central

    Osoba, Tolu; Scott, Lesley; Motlhaoleng, Katlego; Rakgokong, Modiehi; Martinson, Neil Alexander

    2016-01-01

    Introduction. Tuberculosis is a major cause of morbidity and mortality especially in high HIV burden settings. Active case finding is one strategy to potentially reduce TB disease burden. Xpert MTB/Rif has recently been recommended for diagnosis of TB. Methods. Pragmatic randomized trial to compare diagnosis rate and turnaround time for laboratory testing for Xpert MTB/Rif with TB microscopy and culture in household contacts of patients recently diagnosed with TB. Results. 2464 household contacts enrolled into the study from 768 active TB index cases. 1068 (44%) were unable to give sputum, but 24 of these were already on TB treatment. 863 (53%) participants sputum samples were tested with smear and culture and 2.7% (23/863; CI: 1.62–3.78) were diagnosed with active TB. Xpert MTB/Rif was used in 515 (21%) participants; active TB was diagnosed in 1.6% (8/515; CI: 0.52–2.68). Discussion and Conclusions. Additional 31 cases were diagnosed with contact tracing of household members. When Xpert MTB/Rif is compared with culture, there is no significant difference in diagnostic yield. PMID:27493800

  9. Evaluation of the Cepheid Xpert MTB/RIF assay for direct detection of Mycobacterium tuberculosis complex in respiratory specimens.

    PubMed

    Marlowe, Elizabeth M; Novak-Weekley, Susan M; Cumpio, Joven; Sharp, Susan E; Momeny, Michelle A; Babst, Anna; Carlson, Jonathan S; Kawamura, Masae; Pandori, Mark

    2011-04-01

    A total of 217 specimens submitted for routine smear and culture from three different sites within the western United States were used to evaluate the GeneXpert MTB/RIF assay (for research use only) (Cepheid, Sunnyvale, CA). Overall agreement compared to culture was 89% (98% for smear positives and 72% for smear negatives) for detection of Mycobacterium tuberculosis. PMID:21289151

  10. The Use of Xpert MTB/Rif for Active Case Finding among TB Contacts in North West Province, South Africa.

    PubMed

    Lebina, Limakatso; Fuller, Nigel; Osoba, Tolu; Scott, Lesley; Motlhaoleng, Katlego; Rakgokong, Modiehi; Abraham, Pattamukkil; Variava, Ebrahim; Martinson, Neil Alexander

    2016-01-01

    Introduction. Tuberculosis is a major cause of morbidity and mortality especially in high HIV burden settings. Active case finding is one strategy to potentially reduce TB disease burden. Xpert MTB/Rif has recently been recommended for diagnosis of TB. Methods. Pragmatic randomized trial to compare diagnosis rate and turnaround time for laboratory testing for Xpert MTB/Rif with TB microscopy and culture in household contacts of patients recently diagnosed with TB. Results. 2464 household contacts enrolled into the study from 768 active TB index cases. 1068 (44%) were unable to give sputum, but 24 of these were already on TB treatment. 863 (53%) participants sputum samples were tested with smear and culture and 2.7% (23/863; CI: 1.62-3.78) were diagnosed with active TB. Xpert MTB/Rif was used in 515 (21%) participants; active TB was diagnosed in 1.6% (8/515; CI: 0.52-2.68). Discussion and Conclusions. Additional 31 cases were diagnosed with contact tracing of household members. When Xpert MTB/Rif is compared with culture, there is no significant difference in diagnostic yield.

  11. Marathon Running Fails to Influence RBC Survival Rates in Iron-Replete Women.

    ERIC Educational Resources Information Center

    Steenkamp, Irene; And Others

    1986-01-01

    This study used radiolabeling to measure red blood cell (RBC) survival rates in six iron-replete female marathon runners, and urinary tests were conducted to search for secondary evidence of RBC damage. The hypothesized RBC fragmentation was not disclosed. (Author/MT)

  12. Attracting Primary School Children to Mathematics: The Case of a City Mathematical Marathon

    ERIC Educational Resources Information Center

    Applebaum, Mark; Freiman, Viktor

    2013-01-01

    In this paper we report on the first year of an online competition in which 480 students took part. After a brief presentation of the organizational structure of the marathon and general data about students' participation, we discuss findings from questionnaires about participants' attitudes towards mathematics, technology, and their perception of…

  13. Writing Marathons Help Build Middle School Students' College Aspirations and Strengthen Their Literacy Skills

    ERIC Educational Resources Information Center

    Radcliffe, Rich A.; Stephens, Liz C.

    2010-01-01

    Young adolescents' low scores on the National Assessment of Educational Progress (NAEP) force the question of whether these students will be ready for college in four years. Our efforts to build a college-going culture emphasize strengthening students' writing skills by using preservice teachers to lead writing marathons for at-risk middle school…

  14. The University of California Institute of Environmental Stress Marathon Field Studies

    ERIC Educational Resources Information Center

    Maron, Michael B.

    2014-01-01

    In 1973, the Institute of Environmental Stress of the University of California-Santa Barbara, under the direction of Steven M. Horvath, began a series of field and laboratory studies of marathon runners during competition. As one of Horvath's graduate students, many of these studies became part of my doctoral dissertation. The rationale for…

  15. Gait Characteristics over the Course of a Race in Recreational Marathon Competitors

    ERIC Educational Resources Information Center

    Bertram, John E. A.; Prebeau-Menezes, Leif; Szarko, Matthew J.

    2013-01-01

    We analyzed gait and function of the supporting limb in participants of a marathon race at three stages: prerace, midrace (18 km), and near the end of the race (36 km). We confirmed that the most successful runners were able to maintain running speed for the duration of the race with little change in speed or gait. Speed slowed progressively…

  16. Developing a Data Visualization System for the Bank of America Chicago Marathon (Chicago, Illinois USA).

    PubMed

    Hanken, Taylor; Young, Sam; Smilowitz, Karen; Chiampas, George; Waskowski, David

    2016-10-01

    As one of the largest marathons worldwide, the Bank of America Chicago Marathon (BACCM; Chicago, Illinois USA) accumulates high volumes of data. Race organizers and engaged agencies need the ability to access specific data in real-time. This report details a data visualization system designed for the Chicago Marathon and establishes key principles for event management data visualization. The data visualization system allows for efficient data communication among the organizing agencies of Chicago endurance events. Agencies can observe the progress of the race throughout the day and obtain needed information, such as the number and location of runners on the course and current weather conditions. Implementation of the system can reduce time-consuming, face-to-face interactions between involved agencies by having key data streams in one location, streamlining communications with the purpose of improving race logistics, as well as medical preparedness and response. Hanken T , Young S , Smilowitz K , Chiampas G , Waskowski D . Developing a data visualization system for the Bank of America Chicago Marathon (Chicago, Illinois USA). Prehosp Disaster Med. 2016;31(5):572-577. PMID:27491334

  17. Developing a Data Visualization System for the Bank of America Chicago Marathon (Chicago, Illinois USA).

    PubMed

    Hanken, Taylor; Young, Sam; Smilowitz, Karen; Chiampas, George; Waskowski, David

    2016-10-01

    As one of the largest marathons worldwide, the Bank of America Chicago Marathon (BACCM; Chicago, Illinois USA) accumulates high volumes of data. Race organizers and engaged agencies need the ability to access specific data in real-time. This report details a data visualization system designed for the Chicago Marathon and establishes key principles for event management data visualization. The data visualization system allows for efficient data communication among the organizing agencies of Chicago endurance events. Agencies can observe the progress of the race throughout the day and obtain needed information, such as the number and location of runners on the course and current weather conditions. Implementation of the system can reduce time-consuming, face-to-face interactions between involved agencies by having key data streams in one location, streamlining communications with the purpose of improving race logistics, as well as medical preparedness and response. Hanken T , Young S , Smilowitz K , Chiampas G , Waskowski D . Developing a data visualization system for the Bank of America Chicago Marathon (Chicago, Illinois USA). Prehosp Disaster Med. 2016;31(5):572-577.

  18. Leg skinfold thicknesses and race performance in male 24-hour ultra-marathoners.

    PubMed

    Knechtle, Beat; Knechtle, Patrizia; Rüst, Christoph Alexander; Rosemann, Thomas

    2011-04-01

    The association of skinfold thicknesses with race performance has been investigated in runners competing over distances of ≤50 km. This study investigated a potential relation between skinfold thicknesses and race performance in male ultra-marathoners completing >50 km in 24 hours. Variables of anthropometry, training, and previous performance were related to race performance in 63 male ultra-marathoners aged 46.9 (standard deviation [SD] 10.3) years, standing 1.78 (SD 0.07) m in height, and weighing 73.3 (SD 7.6) kg. The runners clocked 146.1 (SD 43.1) km during the 24 hours. In the bivariate analysis, several variables were associated with race performance: body mass (r = -0.25); skinfold thickness at axilla (r = -0.37), subscapula (r = -0.28), abdomen (r = -0.31), and suprailiaca (r = -0.30); the sum of skinfold thicknesses (r = -0.32); percentage body fat (r = -0.32); weekly kilometers run (r = 0.31); personal best time in a marathon (r = -0.58); personal best time in a 100-km ultra-run (r = -0.31); and personal best performance in a 24-hour run (r = 0.46). In the multivariate analysis, no anthropometric or training variable was related to race performance. In conclusion, in contrast to runners up to distances of 50 km, skinfold thicknesses of the lower limbs were not related to race performance in 24-hour ultra-marathoners.

  19. Effects of Structure of Marathon Group Therapy and Locus of Control on Therapeutic Outcome

    ERIC Educational Resources Information Center

    Kilmann, Peter R.; Howell, Robert J.

    1974-01-01

    This study compared the outcome of external and internal scorers on the locus of control scale and considered the association between internal-external orientation and direct and nondirect marathon group therapy. The findings suggest that internals are better therapeutic risks than externals, regardless of a direct or nondirect therapist…

  20. Marathons versus Spaced Groups: Skin Conductance and the Effects of Time Distribution on Encounter Group Learning.

    ERIC Educational Resources Information Center

    Loomis, Thomas P.

    1988-01-01

    Randomly assigned 41 students to 2 twice-weekly groups, which met for 3 hours eight times; 2 marathons, which met continuously for 24 hours; and nontreatment control group. Treatment groups had significant positive changes on 14 of 15 measured personality variables between pre- and post-test, and positive change on all dependent measures between…

  1. Self-Perception and Interpersonal Behavior Changes in Marathon and Time-Extended Encounter Groups

    ERIC Educational Resources Information Center

    Marks, Michael W.; Vestre, Norris D.

    1974-01-01

    College students (N=27) were assigned to a time-extended or a marathon group or a control condition to evaluate the effects of encounter experiences on self-perception and interpersonal behavior. Both experimental groups showed significantly greater changes in self-perceptions from pretest to posttest than the control group. (Author)

  2. 'How to know what you need to do': a cross-country comparison of maternal health guidelines in Burkina Faso, Ghana and Tanzania

    PubMed Central

    2012-01-01

    Background Initiatives to raise the quality of care provided to mothers need to be given priority in Sub Saharan Africa (SSA). The promotion of clinical practice guidelines (CPGs) is a common strategy, but their implementation is often challenging, limiting their potential impact. Through a cross-country perspective, this study explored CPGs for maternal health in Burkina Faso, Ghana, and Tanzania. The objectives were to compare factors related to CPG use including their content compared with World Health Organization (WHO) guidelines, their format, and their development processes. Perceptions of their availability and use in practice were also explored. The overall purpose was to further the understanding of how to increase CPGs' potential to improve quality of care for mothers in SSA. Methods The study was a multiple case study design consisting of cross-country comparisons using document review and key informant interviews. A conceptual framework to aid analysis and discussion of results was developed, including selected domains related to guidelines' implementability and use by health workers in practice in terms of usability, applicability, and adaptability. Results The study revealed few significant differences in content between the national guidelines for maternal health and WHO recommendations. There were, however, marked variations in the format of CPGs between the three countries. Apart from the Ghanaian and one of the Tanzanian CPGs, the levels of both usability and applicability were assessed as low or medium. In all three countries, the use of CPGs by health workers in practice was perceived to be limited. Conclusion Our cross-country study suggests that it is not poor quality of content or lack of evidence base that constitute the major barrier for CPGs to positively impact on quality improvement in maternal care in SSA. It rather emphasises the need to prioritise the format of guidelines to increase their usability and applicability and to consider

  3. The effectiveness of stretch-shortening cycling in upper-limb extensor muscles during elite cross-country skiing with the double-poling technique.

    PubMed

    Zoppirolli, Chiara; Holmberg, Hans-Christer; Pellegrini, Barbara; Quaglia, Diego; Bortolan, Lorenzo; Schena, Federico

    2013-12-01

    This investigation was designed to evaluate the effectiveness of stretch-shortening cycling (SSC(EFF)) in upper-limb extensor muscles while cross-country skiing using the double-poling technique (DP). To this end, SSC(EFF) was analyzed in relation to DP velocity and performance. Eleven elite cross-country skiers performed an incremental test to determine maximal DP velocity (V(max)). Thereafter, cycle characteristics, elbow joint kinematics and poling forces were monitored on a treadmill while skiing at two sub-maximal and racing velocity (85% of V(max)). The average EMG activities of the triceps brachii and latissimus dorsi muscles were determined during the flexion and extension sub-phases of the poling cycle (EMG(FLEX), EMG(EXT)), as well as prior to pole plant (EMG(PRE)). SSC(EFF) was defined as the ratio of aEMG(FLEX) to aEMG(EXT). EMG(PRE) and EMG(FLEX) increased with velocity for both muscles (P < 0.01), as did SSC(EFF) (from 0.9 ± 0.3 to 1.3 ± 0.5 for the triceps brachii and from 0.9 ± 0.4 to 1.5 ± 0.5 for the latissimus dorsi) and poling force (from 253 ± 33 to 290 ± 36N; P < 0.05). Furthermore, SSC(EFF) was positively correlated to Vmax, to EMG(PRE) and EMG(FLEX) (P < 0.05). The neuromuscular adaptations made at higher velocities, when more poling force must be applied to the ground, exert a major influence on the DP performance of elite cross-country skiers.

  4. Men are More Likely than Women to Slow in the Marathon

    PubMed Central

    Deaner, Robert O.; Carter, Rickey E.; Joyner, Michael J.; Hunter, Sandra K.

    2014-01-01

    Studies of non-elite distance runners suggest that men are more likely than women to slow their pace in the marathon. Purpose This study determined the reliability of the sex difference in pacing across many marathons, and after adjusting women’s performances by 12% to address men’s greater maximal oxygen uptake and also incorporating information on racing experience. Methods Data was acquired from 14 U.S. marathons in 2011, and encompassed 91,929 performances. For 2,929 runners, we obtained experience data from a race-aggregating website. We operationalized pace maintenance as percentage change in pace observed in the second half of the marathon relative to the first half. Pace maintenance was analyzed as a continuous variable and as two categorical variables: “maintain the pace,” defined as slowing < 10%; and “marked slowing,” defined as slowing ≥30%. Results The mean change in pace was 15.6% and 11.7% for men and women, respectively (P<0.0001). This sex difference was significant for all 14 marathons. The odds for women were 1.46 (95% CI: 1.41 to 1.50, P<0.0001) times higher than men to maintain the pace and 0.36 (95% CI: 0.34–0.38; P<0.0001) times that of men to exhibit marked slowing. Slower finishing times were associated with greater slowing, especially in men (interaction, P<.0001). However, the sex difference in pacing occurred across age and finishing-time groups. Making the 12% adjustment to women’s performances lessened the magnitude of the sex difference in pacing but not its occurrence. Although greater experience was associated with lesser slowing, controlling for the experience variables did not eliminate the sex difference in pacing. Conclusions The sex difference in pacing is robust. It may reflect sex differences in physiology, decision making, or both. PMID:24983344

  5. The relationship between age and running time in elite marathoners is U-shaped.

    PubMed

    Lara, Beatriz; Salinero, Juan José; Del Coso, Juan

    2014-04-01

    Several investigations have demonstrated that running performance gradually decreases with age by using runners >25 years grouped in 5-year age brackets. The aim of this study was to determine the relationship between race time in marathon and age in elite marathoners by including all ages and 1-year intervals. Running times of the top ten men and women at 1-year intervals (from 18 to 75 years) in the New York City marathon were analyzed for the 2010 and 2011 races. Gender differences in performance times were analyzed between 18 and 70 years of age. The relationship between running time and runner's age was U-shaped: the lowest race time was obtained at 27 years (149 ± 14 min) in men and at 29 years (169 ± 17 min) in women. Before this age (e.g., 27 years for men and 29 years for women), running time increased by 4.4 ± 4.0 % per year in men and 4.4 ± 4.3 % per year in women. From this age on, running time increased by 2.4 ± 8.1 % per year in men and 2.5 ± 9.9 % per year in women. The sex difference in running time remained stable at ~18.7 ± 3.1 % from 18 to 57 years of age. After this, sex difference progressively increased with advancing age. In summary, endurance runners obtained their best performance in the marathon at 27 years in men and 29 in women. Thus, elite marathon runners should program their long-term training to obtain maximal performance during their late 20s.

  6. Tectonic interpretation of the westernmost part of the Ouachita-Marathon (Hercynian) orogenic belt, west Texas Mexico

    NASA Astrophysics Data System (ADS)

    Shurbet, D. H.; Cebull, S. E.

    1987-05-01

    The disposition of the Ouachita-Marathon orogenic belt as it extends through west Texas into Mexico has been the subject of diverse interpretations. However, an explanation developed earlier for the general shape of the Ouachita-Marathon orogenic belt in the southern United States, which was based on the relation of craton margin to direction of Paleozoic plate motion, is adequate to account for the belt's puzzling disposition upon entering Mexico. It is suggested that crustal thickness, gravity, and geologic data indicate that the orogen follows the shape of the craton margin, which swings around a reentrant south of the Marathon region and extends southward into Mexico. In Mexico the orogen apparently ends in association with the westernmost of the Ouachita-Marathon zones of transform offset.

  7. A 10-year follow-up study of pulmonary function in symptomatic elite cross-country skiers--athletes and bronchial dysfunctions.

    PubMed

    Vergès, Samuel; Flore, Patrice; Blanchi, Marie-Philippe Rousseau; Wuyam, Bernard

    2004-12-01

    A high prevalence of asthma-like symptoms and abnormal bronchial reactivity to various stimuli has been reported among endurance athletes. This report presents the cases of three cross-country skiers who have shown a progressive development of airway obstruction during their sport careers. The observed decline in FEV1, FEV1/FVC and/or FVC (FEV, forced expiratory volume; FVC, forced expiratory vital capacity) was greater than expected from longitudinal regression equations describing the ageing effect on pulmonary function. The three subjects encountered abnormal respiratory discomfort during their sport activity which was not systematically associated with abnormal bronchial reactivity (either to methacholine or exercise hyperventilation). At the end of the follow-up periods (9-12 years), all three skiers presented objective signs of airflow limitations during intense exercise. This report suggests that repeated chronic hyperventilation of cold dry air in cross-country skiers for several years can induce permanent bronchial disorders which may include remodeling processes and induce ventilatory limitations during intense exercise.

  8. Effect of an intense period of competition on race performance and self-reported illness in elite cross-country skiers.

    PubMed

    Svendsen, I S; Gleeson, M; Haugen, T A; Tønnessen, E

    2015-12-01

    The aim of this study was to determine whether participating in a cross-country skiing stage race (Tour de Ski; TDS) affects subsequent illness incidence, training, and race performance. Self-reported training and illness data from 44 male and female elite cross-country skiers were included. In total, 127 years of data were collected (2-3 seasons per athlete). Illness incidence, training load, and performance in international competitions were calculated for athletes who did and did not participate in TDS. Forty-eight percent of athletes reported becoming ill during or in the days immediately after taking part in TDS vs 16% of athletes who did not participate. In both groups, illness incidence was somewhat lower for female athletes. For male athletes, race performance was significantly worse for 6 weeks following TDS vs 6 weeks before TDS. Furthermore, while female athletes who participated in TDS performed relatively better than controls in Olympics/World Championships, male athletes who participated in TDS typically performed worse in subsequent major championships. Participating in TDS appears to result in ∼ 3-fold increase in risk of illness in this period. Male athletes appear more prone to illness and also see a drop in race performance following TDS, possibly linked to differences in training load before and after the event.

  9. Effect of an intense period of competition on race performance and self-reported illness in elite cross-country skiers.

    PubMed

    Svendsen, I S; Gleeson, M; Haugen, T A; Tønnessen, E

    2015-12-01

    The aim of this study was to determine whether participating in a cross-country skiing stage race (Tour de Ski; TDS) affects subsequent illness incidence, training, and race performance. Self-reported training and illness data from 44 male and female elite cross-country skiers were included. In total, 127 years of data were collected (2-3 seasons per athlete). Illness incidence, training load, and performance in international competitions were calculated for athletes who did and did not participate in TDS. Forty-eight percent of athletes reported becoming ill during or in the days immediately after taking part in TDS vs 16% of athletes who did not participate. In both groups, illness incidence was somewhat lower for female athletes. For male athletes, race performance was significantly worse for 6 weeks following TDS vs 6 weeks before TDS. Furthermore, while female athletes who participated in TDS performed relatively better than controls in Olympics/World Championships, male athletes who participated in TDS typically performed worse in subsequent major championships. Participating in TDS appears to result in ∼ 3-fold increase in risk of illness in this period. Male athletes appear more prone to illness and also see a drop in race performance following TDS, possibly linked to differences in training load before and after the event. PMID:25818900

  10. Resveratrol exerts no effect on inflammatory response and delayed onset muscle soreness after a marathon in male athletes.

    PubMed Central

    Laupheimer, M W; Perry, M; Benton, S; Malliaras, P; Maffulli, N

    2014-01-01

    Objective We investigated whether the inflammatory response and delayed onset of muscle soreness after a marathon are altered by resveratrol, a natural polyphenolic flavonoid antioxidant. Design: Double blind placebo-controlled randomised pilot study. Setting: London Marathon. Participants: Marathon race participants Interventions: 7 healthy male athletes were randomised to receive Resveratrol (600 mg Resveratrol daily for 7 days immediately before the marathon) or a placebo. Main Outcome Measurements: Blood samples taken 48 hours before and 18–32 hours after the marathon were analysed for white blood cell count (WBC) and C-reactive protein (CRP). A VAS score was taken at the same times as the blood samples to assess delayed onset muscle soreness. Results: There were no significant differences between the two groups in terms of changes occurring between pre- and post- tests for WBC, CRP or VAS. Conclusions: There were no differences in immune response or delayed onset muscle soreness between resveratrol and placebo after a marathon. Further investigations are needed with longer treatment time and higher doses, analysing additional parameters such interleukins for a possible effect of resveratrol on the inflammatory response due to extensive exercise. To avoid a type II error, 17 subjects in each group would be required. PMID:25147765

  11. Evaluation of the implementation of the Xpert® MTB/RIF assay in Fiji

    PubMed Central

    Gounder, S.; Reid, S. A.

    2014-01-01

    Setting: All Xpert® MTB/RIF tests performed in the three TB (tuberculosis) treatment centres in Fiji from June 2012 to February 2013. Objectives: To determine 1) the number of Xpert tests performed in each centre, 2) the association between sputum quality and Xpert results, 3) the agreement of Xpert with acid-fast bacilli (AFB) smear microscopy and TB culture and 4) error rates. Design: Retrospective review of records. Results: A total of 415 Xpert tests were performed in the study period. Mycobacterium tuberculosis was detected in 69 (16.6%) samples. No rifampicin resistance was detected. M. tuberculosis was detected from 60 (18.7%) good-quality sputum samples. A total of 43 (10.4%) errors occurred during this period. M. tuberculosis was detected in 10 (2.9%) smear-negative specimens. There was a substantial and an almost perfect agreement between Xpert and AFB microscopy (κ = 0.793) and culture results (κ = 0.818), respectively. Conclusion: Although a good correlation between Xpert and the two tests were shown in the study, Xpert should not replace the routine first-line TB diagnostic tests used in Fiji for reasons related to logistics and sustainability. A further evaluation of the assay's performance is required over a longer time period to gauge its diagnostic value in detecting smear-negative, Xpert-positive cases in Fiji. PMID:26400807

  12. Mixed impact of Xpert® MTB/RIF on tuberculosis diagnosis in Cambodia

    PubMed Central

    Moore, B. K.; Kyle, R. P.; Eng, B.; Nong, K.; Pevzner, E. S.; Eam, K. K.; Eang, M. T.; Killam, W. P.

    2016-01-01

    Setting: National Tuberculosis (TB) Program sites in northwest Cambodia. Objective: To evaluate the impact of Xpert® MTB/RIF at point of care (POC) as compared to non-POC sites on the diagnostic evaluation of people living with the human immunodeficiency virus (PLHIV) with TB symptoms and patients with possible multidrug-resistant (MDR) TB. Design: Observational cohort of patients undergoing routine diagnostic evaluation for TB following the rollout of Xpert. Results: Between October 2011 and June 2013, 431 of 822 (52%) PLHIV with TB symptoms and 240/493 (49%) patients with possible MDR-TB underwent Xpert. Xpert was more likely to be performed when available as POC. A smaller proportion of PLHIV at POC sites were diagnosed with TB than at non-POC sites; however, at POC sites, a higher proportion of those diagnosed with TB were bacteriologically positive. There was poor agreement between Xpert and other tests such as smear microscopy and culture. Overall, the evaluation of patients with possible MDR-TB increased following Xpert rollout, yet for patients confirmed as having drug resistance on drug susceptibility testing, only 46% had rifampin resistance that would be identified with Xpert. Conclusion: Although utilization of Xpert was low, it may have contributed to an increase in evaluations for possible MDR-TB and a decline in empiric treatment for PLHIV when available as POC. PMID:27358807

  13. Evaluation of GeneXpert MTB/RIF assay for direct diagnosis of pulmonary tuberculosis

    PubMed Central

    Moussa, Husseiny Sh.; Bayoumi, Faten S.; Ali, Ahmed M.

    2016-01-01

    Objectives: To evaluate the performance of GeneXpert MTB/RIF assay for direct diagnosis of pulmonary tuberculosis (PTB). Methods: This is a cross-sectional study conducted between October 2013 and February 2016 at Abbassaia Chest Hospital and Ain Shams University Hospital, Cairo, Egypt. Inclusion criteria were adults between 18 and 60 years with suspected PTB and classified into 5 clinical categories based on their clinical, radiological, and laboratory findings: confirmed TB, probable TB, possible TB, unlikely TB, and not TB. Two sputum samples from each participant were analyzed by GX and the results were compared by conventional culture. Results: In total, 218 participants were enrolled: 71 had confirmed TB; 112, highly probable TB; 20, probable TB; 10, unlikely TB; and 5, no TB. The sensitivity and specificity of the GX assay were 93% and 98.3% respectively. GeneXpert was positive in 93% of confirmed TB and 2.2% of probable TB cases. Conclusions: GeneXpert is a rapid and promising technique with good sensitivity (93%) and specificity (98.3%), but it cannot be used as a standalone PTB diagnostic tool. There is a need for more GX evaluation studies in countries with low TB incidence. PMID:27652357

  14. Xpert MTB/RIF detection of rifampin resistance and time to treatment initiation in Harare, Zimbabwe

    PubMed Central

    Metcalfe, John Z.; Makumbirofa, Salome; Makamure, Beauty; Sandy, Charles; Bara, Wilbert; Mason, Peter; Hopewell, Philip C.

    2016-01-01

    Background Patients at elevated risk of drug-resistant tuberculosis are prioritized for testing with Xpert MTB/RIF® (“Xpert”), though clinical utility in this population is understudied. Design From November 2011 to June 2014, consecutive outpatients with history of prior tuberculosis in high-density suburbs of Harare, Zimbabwe were tested with Xpert, solid and liquid culture, and the microscopically-observed drug susceptibility assay. Diagnostic accuracy for rifampin-resistance and time to second-line regimens were ascertained. The rpoB gene was sequenced in cases of culture-confirmed rifampin resistance and genotypic sensitivity. Results Among 352 retreatment patients, 71 (20%) had rifampin-resistant, 98 (28%) rifampin-susceptible, 64 (18%) culture-negative/Xpert-positive, and 119 (34%) culture-negative/Xpert-negative TB. Xpert was 86% (95% CI 75-93%) sensitive and 98% (95% CI 92-100%) specific for rifampin-resistant TB. The positive predictive value of Xpert-determined rifampin resistance for MDR-TB was 82% (95% CI 70-91%). Fifty-nine of 71 (83%) participants initiated SLDs, with a median time to regimen initiation of 18 days (IQR, 10-44 days). Conclusion The diagnostic accuracy of Xpert for rifampin-resistance is high, though predictive value for MDR-TB is lower than anticipated. Xpert allows for faster SLD initiation under programmatic conditions, relative to culture-based drug susceptibility testing. PMID:27287639

  15. Xpert MTB/RIF - why the lack of morbidity and mortality impact in intervention trials?

    PubMed

    Auld, Andrew F; Fielding, Katherine L; Gupta-Wright, Ankur; Lawn, Stephen D

    2016-08-01

    Compared with smear microscopy, the Xpert MTB/RIF assay (Xpert), with superior accuracy and capacity to diagnose rifampicin resistance, has advanced TB diagnostic capability. However, recent trials of Xpert impact have not demonstrated reductions in patient morbidity and mortality. We conducted a narrative review of Xpert impact trials to summarize which patient-relevant outcomes Xpert has improved and explore reasons for no observed morbidity or mortality reductions. We searched PubMed, Google Scholar, Cochrane Library and Embase and identified eight trials meeting inclusion criteria: three individually randomized, three cluster-randomized, and two pre-post trials. In six trials Xpert increased diagnostic yield of bacteriologically-confirmed TB from sputa and in four trials Xpert shortened time to TB treatment. However, all-cause mortality was similar between arms in all six trials reporting this outcome, and the only trial to assess Xpert impact on morbidity reported no impact. Trial characteristics that might explain lack of observed impact on morbidity and mortality include: higher rates of empiric TB treatment in microscopy compared with Xpert arms, enrollment of study populations not comprised exclusively of populations most likely to benefit from Xpert, and health system weaknesses. So far as equipoise exists, future trials that address past limitations are needed to inform Xpert use in resource-limited settings. PMID:27638038

  16. A model of tuberculosis screening for pregnant women in resource-limited settings using Xpert MTB/RIF.

    PubMed

    Turnbull, Eleanor R; Kancheya, Nzali G; Harris, Jennifer B; Topp, Stephanie M; Henostroza, German; Reid, Stewart E

    2012-01-01

    Timely diagnosis and treatment of maternal tuberculosis (TB) is important to reduce morbidity and mortality for both the mother and child, particularly in women who are coinfected with HIV. The World Health Organization (WHO) recommends the integration of TB/HIV screening into antenatal services but available diagnostic tools are slow and insensitive, resulting in delays in treatment initiation. Recently the WHO endorsed Xpert MTB/RIF, a highly sensitive, real-time PCR assay for Mycobacterium tuberculosis that simultaneously detects rifampicin resistance directly from sputum and provides results within 100 minutes. We propose a model for same-day TB screening and diagnosis of all pregnant women at antenatal care using Xpert MTB/RIF. Pilot studies are urgently required to evaluate strategies for the integration of TB screening into antenatal clinics using new diagnostic technologies.

  17. Multicenter Feasibility Study To Assess External Quality Assessment Panels for Xpert MTB/RIF Assay in South Africa

    PubMed Central

    Albert, Heidi; Gilpin, Chris; Alexander, Heather; DeGruy, Kyle; Stevens, Wendy

    2014-01-01

    External quality assessment (EQA) for the Xpert MTB/RIF assay is part of the quality system required for clinical and laboratory practice. Five newly developed EQA panels that use different matrices, including a lyophilized sample (Vircell, Granada, Spain), a dried tube specimen (CDC), liquid (Maine Molecular Quality Control, Inc. [MMQCI], Scarborough, ME), artificial sputum (Global Laboratory Initiative [GLI]), and a dried culture spot (National Health Laboratory Services [NHLS]), were evaluated at 11 GeneXpert testing sites in South Africa. The panels comprised Mycobacterium tuberculosis complex (MTBC)-negative, MTBC-positive (including rifampin [RIF] susceptible and RIF resistant), and nontuberculosis mycobacterial material that was inactivated and safe for transportation. Twelve qualitative and quantitative variables were scored as acceptable (1) or unacceptable (0); the overall panel performance score for the Vircell, CDC, GLI, and NHLS panels was 9 of 12, while the MMQCI panel scored 6 of 12 (owing to the need for cold chain maintenance). All panels showed good compatibility with Xpert MTB/RIF testing, and none showed PCR inhibition. The use of a liquid or dry matrix did not appear to be a distinguishing criterion, as both matrices had reduced scores on insufficient volumes, a need for extra consumables, and the ability to transfer to the Xpert MTB/RIF cartridge. EQA is an important component of the quality system required for diagnostic testing programs, but it must be complemented by routine monitoring of performance indicators and instrument verification. This study aims to introduce EQA concepts for Xpert MTB/RIF testing and evaluates five potential EQA panels. PMID:24789182

  18. The sea urchin metallothionein system: Comparative evaluation of the SpMTA and SpMTB metal-binding preferences☆

    PubMed Central

    Tomas, Mireia; Domènech, Jordi; Capdevila, Mercè; Bofill, Roger; Atrian, Sílvia

    2013-01-01

    Metallothioneins (MTs) constitute a superfamily of ubiquitous metal-binding proteins of low molecular weight and high Cys content. They are involved in metal homeostasis and detoxification, amongst other proposed biological functions. Two MT isoforms (SpMTA and SpMTB) have been reported in the echinoderm Strongylocentrotus purpuratus (sea urchin), both containing 20 Cys residues and presenting extremely similar sequences, although showing distinct tissular and ontogenic expression patterns. Although exhaustive information is available for the Cd(II)-SpMTA complex, this including the full resolution of its 3D structure, no data has been reported concerning either SpMTA Zn(II) and Cu(I) binding properties, or the characterization of SpMTB at protein level. In this work, both the SpMTA and SpMTB isoforms, as well as their separate α and β domains, have been recombinantly synthesized in the presence of Zn(II), Cd(II) or Cu(II), and the corresponding metal complexes have been analyzed using electrospray mass spectrometry, and CD, ICP-AES and UV–vis spectroscopies. The results clearly show a better performance of isoform A when binding Zn(II) and Cd(II), and of isoform B when coordinating Cu(I). Thus, our results confirm the differential metal binding preference of SpMTA and SpMTB, which, together with the reported induction pattern of the respective genes, highlights how also in Echinodermata the MT polymorphism may be linked to the evolution of different physiological roles. PMID:23847757

  19. Evaluation of GenoFlow DR-MTB Array Test for Detection of Rifampin and Isoniazid Resistance in Mycobacterium tuberculosis

    PubMed Central

    Molina-Moya, B.; Kazdaglis, G.; Lacoma, A.; Prat, C.; Gómez, A.; Villar-Hernández, R.; García-García, E.; Haba, L.; Maldonado, J.; Samper, S.; Ruiz-Manzano, J.; Ausina, V.

    2016-01-01

    The aim of this study was to evaluate the GenoFlow DR-MTB array test (DiagCor Bioscience, Hong Kong) on 70 cultured isolates and 50 sputum specimens. The GenoFlow array test showed good sensitivity and specificity compared to the phenotypic Bactec 460TB. This array accurately detected mutations in rpoB, katG, and inhA associated with resistance to rifampin and isoniazid. PMID:26865688

  20. Evaluation of GenoFlow DR-MTB Array Test for Detection of Rifampin and Isoniazid Resistance in Mycobacterium tuberculosis.

    PubMed

    Molina-Moya, B; Kazdaglis, G; Lacoma, A; Prat, C; Gómez, A; Villar-Hernández, R; García-García, E; Haba, L; Maldonado, J; Samper, S; Ruiz-Manzano, J; Ausina, V; Domínguez, J

    2016-04-01

    The aim of this study was to evaluate the GenoFlow DR-MTB array test (DiagCor Bioscience, Hong Kong) on 70 cultured isolates and 50 sputum specimens. The GenoFlow array test showed good sensitivity and specificity compared to the phenotypic Bactec 460TB. This array accurately detected mutations inrpoB,katG, andinhAassociated with resistance to rifampin and isoniazid. PMID:26865688

  1. SAR Studies on Trisubstituted Benzimidazoles as Inhibitors of Mtb FtsZ for the Development of Novel Antitubercular Agents

    PubMed Central

    Awasthi, Divya; Kumar, Kunal; Knudson, Susan E.; Slayden, Richard A.; Ojima, Iwao

    2014-01-01

    FtsZ, an essential protein for bacterial cell division, is a highly promising therapeutic target, especially for the discovery and development of new-generation anti-TB agents. Following up the identification of two lead 2,5,6-trisubstituted benzimidazoles, 1 and 2, targeting Mtb-FtsZ in our previous study, an extensive SAR study for optimization of these lead compounds was performed through systematic modification of the 5 and 6 positions. This study has successfully led to the discovery of a highly potent advanced lead 5f (MIC 0.06 µg/mL) and several other compounds with comparable potencies. These advanced lead compounds possess a dimethylamino group at the 6 position. The functional groups at the 5 position exhibit substantial effects on the antibacterial activity as well. In vitro experiments such as the FtsZ polymerization inhibitory assay and TEM analysis of Mtb-FtsZ treated with 5f and others indicate that Mtb-FtsZ is the molecular target for their antibacterial activity. PMID:24266862

  2. Runners as sport tourists: the experience and travel behaviors of Ljubljana Marathon participants.

    PubMed

    Rauter, Samo; Doupona Topić, Mojca

    2014-09-01

    The study analysed the experiences of participants on mass sport events, and explained the influence of such sport events on the lifestyle of runners. The study sample consisted of 664 participants of the 15th Ljubljana Marathon. The TRPS questionnaire was adjusted to establish the tourist roles. The role of sport tourists was assumed by 29.8% of all participants. Sport tourists who take various trips mainly for sport purposes (66.7%) participate more often in mass sport events at home and abroad and are more physically active in their leisure time. Moreover, 13 in-depth interviews were conducted with selected marathon participants. It was established that different travel behaviour and experiences from earlier sport events have influenced on their lifestyles. PMID:25420373

  3. Runners as sport tourists: the experience and travel behaviors of Ljubljana Marathon participants.

    PubMed

    Rauter, Samo; Doupona Topić, Mojca

    2014-09-01

    The study analysed the experiences of participants on mass sport events, and explained the influence of such sport events on the lifestyle of runners. The study sample consisted of 664 participants of the 15th Ljubljana Marathon. The TRPS questionnaire was adjusted to establish the tourist roles. The role of sport tourists was assumed by 29.8% of all participants. Sport tourists who take various trips mainly for sport purposes (66.7%) participate more often in mass sport events at home and abroad and are more physically active in their leisure time. Moreover, 13 in-depth interviews were conducted with selected marathon participants. It was established that different travel behaviour and experiences from earlier sport events have influenced on their lifestyles. PMID:25507357

  4. Marathon: An Open Source Software Library for the Analysis of Markov-Chain Monte Carlo Algorithms.

    PubMed

    Rechner, Steffen; Berger, Annabell

    2016-01-01

    We present the software library marathon, which is designed to support the analysis of sampling algorithms that are based on the Markov-Chain Monte Carlo principle. The main application of this library is the computation of properties of so-called state graphs, which represent the structure of Markov chains. We demonstrate applications and the usefulness of marathon by investigating the quality of several bounding methods on four well-known Markov chains for sampling perfect matchings and bipartite graphs. In a set of experiments, we compute the total mixing time and several of its bounds for a large number of input instances. We find that the upper bound gained by the famous canonical path method is often several magnitudes larger than the total mixing time and deteriorates with growing input size. In contrast, the spectral bound is found to be a precise approximation of the total mixing time. PMID:26824442

  5. Marathon: An Open Source Software Library for the Analysis of Markov-Chain Monte Carlo Algorithms.

    PubMed

    Rechner, Steffen; Berger, Annabell

    2016-01-01

    We present the software library marathon, which is designed to support the analysis of sampling algorithms that are based on the Markov-Chain Monte Carlo principle. The main application of this library is the computation of properties of so-called state graphs, which represent the structure of Markov chains. We demonstrate applications and the usefulness of marathon by investigating the quality of several bounding methods on four well-known Markov chains for sampling perfect matchings and bipartite graphs. In a set of experiments, we compute the total mixing time and several of its bounds for a large number of input instances. We find that the upper bound gained by the famous canonical path method is often several magnitudes larger than the total mixing time and deteriorates with growing input size. In contrast, the spectral bound is found to be a precise approximation of the total mixing time.

  6. Smectite deposits in Marathon Valley, Endeavour Crater, Mars, identified using CRISM hyperspectral reflectance data

    NASA Astrophysics Data System (ADS)

    Fox, V. K.; Arvidson, R. E.; Guinness, E. A.; McLennan, S. M.; Catalano, J. G.; Murchie, S. L.; Powell, K. E.

    2016-05-01

    The ~100 m wide Marathon Valley crosscuts the Cape Tribulation rim segment of the 22 km diameter, Noachian-age Endeavour impact crater on Mars. Single-scattering albedo spectra retrieved from three Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) Full-Resolution Targeted (FRT, regularized to 18 m/pixel) and two Along Track Oversampled (ATO, regularized to 12 m/pixel) observations indicate the presence of Fe3+-Mg2+ smectite exposures located in Marathon Valley with combination vibration metal-OH absorption strength comparable to smectite spectral signatures in Mawrth Vallis. The Opportunity rover was directed to the exposures and documented the presence of Shoemaker formation impact breccias that have been isochemically altered, likely by fracture-controlled aqueous fluids.

  7. Marathon: An Open Source Software Library for the Analysis of Markov-Chain Monte Carlo Algorithms

    PubMed Central

    Rechner, Steffen; Berger, Annabell

    2016-01-01

    We present the software library marathon, which is designed to support the analysis of sampling algorithms that are based on the Markov-Chain Monte Carlo principle. The main application of this library is the computation of properties of so-called state graphs, which represent the structure of Markov chains. We demonstrate applications and the usefulness of marathon by investigating the quality of several bounding methods on four well-known Markov chains for sampling perfect matchings and bipartite graphs. In a set of experiments, we compute the total mixing time and several of its bounds for a large number of input instances. We find that the upper bound gained by the famous canonical path method is often several magnitudes larger than the total mixing time and deteriorates with growing input size. In contrast, the spectral bound is found to be a precise approximation of the total mixing time. PMID:26824442

  8. Twitter as a Sentinel in Emergency Situations: Lessons from the Boston Marathon Explosions

    PubMed Central

    Cassa, Christopher A.; Chunara, Rumi; Mandl, Kenneth; Brownstein, John S

    2013-01-01

    Immediately following the Boston Marathon attacks, individuals near the scene posted a deluge of data to social media sites. Previous work has shown that these data can be leveraged to provide rapid insight during natural disasters, disease outbreaks and ongoing conflicts that can assist in the public health and medical response. Here, we examine and discuss the social media messages posted immediately after and around the Boston Marathon bombings, and find that specific keywords appear frequently prior to official public safety and news media reports. Individuals immediately adjacent to the explosions posted messages within minutes via Twitter which identify the location and specifics of events, demonstrating a role for social media in the early recognition and characterization of emergency events. *Christopher Cassa and Rumi Chunara contributed equally to this work. PMID:23852273

  9. Devonian Novaculites as source of oil in Marathon-Ouachita thrust system

    SciTech Connect

    Zemmels, I.; Grizzle, P.L.; Walters, C.C.; Haney, F.R.

    1985-02-01

    The Arkansas Novaculite of southern Oklahoma and the Caballos Novaculite of west Texas (both Devonian) form fractured reservoirs in the Marathon-Ouachita thrust system. These formations were examined to ascertain their petroleum potential. Findings include the following. (1) The thermal maturity of the thrust system conforms to the maturity of the sequence that it has overthrust, suggesting that this allochthonous facies is not anomalously mature. (2) Shale units within the novaculites contain oil-prone organic matter in sufficient concentrations to constitute source rocks. (3) The composition of oils from Isom Springs field in southern Oklahoma and from McKay Creek field in west Texas is virtually identical and generally resembles Devonian oils in Oklahoma and west Texas. The authors concluded that the Devonian novaculites of the Marathon-Ouachita thrust system are self sourcing and do not require a fortuitous juxtaposition of source rocks of a different age to produce a commercial deposit.

  10. Will the age of peak ultra-marathon performance increase with increasing race duration?

    PubMed Central

    2014-01-01

    Background Recent studies found that the athlete’s age of the best ultra-marathon performance was higher than the athlete’s age of the best marathon performance and it seemed that the athlete’s age of peak ultra-marathon performance increased in distance-limited races with rising distance. Methods We investigated the athlete’s age of peak ultra-marathon performance in the fastest finishers in time-limited ultra-marathons from 6 hrs to 10 d. Running performance and athlete’s age of the fastest women and men competing in 6 hrs, 12 hrs, 24 hrs, 48 hrs, 72 hrs, 144 hrs (6 d) and 240 hrs (10 d) were analysed for races held between 1975 and 2012 using analysis of variance and multi-level regression analysis. Results The athlete’s ages of the ten fastest women ever in 6 hrs, 12 hrs, 24 hrs, 48 hrs, 72 hrs, 6 d and 10 d were 41 ± 9, 41 ± 6, 42 ± 5, 46 ± 5, 44 ± 6, 42 ± 4, and 37 ± 4 yrs, respectively. The athlete’s age of the ten fastest women was different between 48 hrs and 10 d. For men, the athlete’s ages were 35 ± 6, 37 ± 9, 39 ± 8, 44 ± 7, 48 ± 3, 48 ± 8 and 48 ± 6 yrs, respectively. The athlete’s age of the ten fastest men in 6 hrs and 12 hrs was lower than the athlete’s age of the ten fastest men in 72 hrs, 6 d and 10 d, respectively. Conclusion The athlete’s age of peak ultra-marathon performance did not increase with rising race duration in the best ultra-marathoners. For the fastest women ever in time-limited races, the athlete’s age was lowest in 10 d (~37 yrs) and highest in 48 hrs (~46 yrs). For men, the athlete’s age of the fastest ever in 6 hrs (~35 yrs) and 12 hrs (~37 yrs) was lower than the athlete’s age of the ten fastest in 72 hrs (~48 yrs), 6 d (~48 yrs) and 10 d (~48 yrs). The differences in the athlete’s age of peak performance between female and male ultra-marathoners for the different race durations need further

  11. Case study: Nutrition and training periodization in three elite marathon runners.

    PubMed

    Stellingwerf, Trent

    2012-10-01

    Laboratory-based studies demonstrate that fueling (carbohydrate; CHO) and fluid strategies can enhance training adaptations and race-day performance in endurance athletes. Thus, the aim of this case study was to characterize several periodized training and nutrition approaches leading to individualized race-day fluid and fueling plans for 3 elite male marathoners. The athletes kept detailed training logs on training volume, pace, and subjective ratings of perceived exertion (RPE) for each training session over 16 wk before race day. Training impulse/load calculations (TRIMP; min × RPE = load [arbitrary units; AU]) and 2 central nutritional techniques were implemented: periodic low-CHO-availability training and individualized CHO- and fluid-intake assessments. Athletes averaged ~13 training sessions per week for a total average training volume of 182 km/wk and peak volume of 231 km/wk. Weekly TRIMP peaked at 4,437 AU (Wk 9), with a low of 1,887 AU (Wk 16) and an average of 3,082 ± 646 AU. Of the 606 total training sessions, ~74%, 11%, and 15% were completed at an intensity in Zone 1 (very easy to somewhat hard), Zone 2 (at lactate threshold) and Zone 3 (very hard to maximal), respectively. There were 2.5 ± 2.3 low-CHO-availability training bouts per week. On race day athletes consumed 61 ± 15 g CHO in 604 ± 156 ml/hr (10.1% ± 0.3% CHO solution) in the following format: ~15 g CHO in ~150 ml every ~15 min of racing. Their resultant marathon times were 2:11:23, 2:12:39 (both personal bests), and 2:16:17 (a marathon debut). Taken together, these periodized training and nutrition approaches were successfully applied to elite marathoners in training and competition. PMID:23011657

  12. Effect of cimetidine on marathon-associated gastrointestinal symptoms and bleeding.

    PubMed

    Moses, F M; Baska, R S; Peura, D A; Deuster, P A

    1991-10-01

    Occult gastrointestinal bleeding occurs in 8-30% of marathon runners. We hypothesized that cimetidine would decrease bleeding by reducing acid-mediated injury and conducted a blinded, placebo-controlled prospective trial to determine the impact of cimetidine on gastrointestinal symptoms and bleeding during a marathon. Thirty participants in the 1989 Marine Corps or New York City marathons completed pre- and postrace: (1) a questionnaire evaluating demographic, medication usage, training history, and gastrointestinal symptoms; (2) three consecutive stool Hemoccult (HO) cards; and (3) a stool Hemoquant (HQ). Fourteen runners (CR) took 800 mg of cimetidine by mouth 2 hr before the start and 16 runners (PR) took placebo. Three subjects were HO+ prerace and were not analyzed. Three subjects failed to take drug as directed and were analyzed as PR. Five of 14 PR and two of 13 CR were HO+ postrace (P greater than 0.05). Prerace HQ values (PR: 1.49 +/- 0.6 and CR: 0.60 +/- 0.1 mg hemoglobin/g stool) were not significantly different from postrace HQ values (PR: 0.73 +/- 0.2 and CR: 0.86 +/- 0.2 mg Hgb/g stool). Despite postrace HO+ conversion, no individual postrace HQ became abnormal. The frequency of gastrointestinal symptoms was similar for CR and PR, as well as HO- and HO+ individuals. Cimetidine did not significantly affect occult gastrointestinal bleeding as measured by HO or HQ results. This suggests that marathon-associated gastrointestinal symptoms and bleeding may be due to lesions other than acid-mediated disease or hemorrhagic gastritis.

  13. Biochemical and Hematological Changes Following the 120-Km Open-Water Marathon Swim

    PubMed Central

    Drygas, Wojciech; Rębowska, Ewa; Stępień, Ewa; Golański, Jacek; Kwaśniewska, Magdalena

    2014-01-01

    Data on physiological effects and potential risks of a ultraendurance swimming are scarce. This report presents the unique case of a 61-year old athlete who completed a non-stop open-water 120-km ultramarathon swim on the Warta River, Poland. Pre-swimming examinations revealed favorable conditions (blood pressure, 110/70 mmHg; rest heart rate, 54 beats/minute, ejection fraction, 60%, 20.2 metabolic equivalents in a maximal exercise test). The swimming time and distance covered were 27 h 33 min and 120 km, respectively. Blood samples for hematological and biochemical parameters were collected 30 min, 4 hrs, 10 hrs and 8 days after the swim. The body temperature of the swimmer was 36.7°C before and 35.1°C after the swim. The hematological parameters remained within the reference range in the postexercise period except for leucocytes (17.5 and 10.6 x G/l noted 30 minutes and 4 hours after the swim, respectively). Serum urea, aspartate aminotransferase and C-reactive protein increased above the reference range reaching 11.3 mmol/l, 1054 nmol/l/s and 25.9 mg/l, respectively. Symptomatic hyponatremia was not observed. Although the results demonstrate that an experienced athlete is able to complete an ultra-marathon swim without negative health consequences, further studies addressing the potential risks of marathon swimming are required. Key points Data on biochemical changes due to long-distance swimming are scarce. This report presents the unique case of a 61-year old athlete who completed a non-stop open-water 120-km ultramarathon swim. An experienced athlete is able to complete an ultra-marathon swim without serious health consequences. Regarding the growing popularity of marathon swimming further studies addressing the potential risks of such exhaustive exercise are required. PMID:25177192

  14. Analysis of performance and age of the fastest 100-mile ultra-marathoners worldwide

    PubMed Central

    Rüst, Christoph Alexander; Knechtle, Beat; Rosemann, Thomas; Lepers, Romuald

    2013-01-01

    OBJECTIVES: The performance and age of peak ultra-endurance performance have been investigated in single races and single race series but not using worldwide participation data. The purpose of this study was to examine the changes in running performance and the age of peak running performance of the best 100-mile ultra-marathoners worldwide. METHOD: The race times and ages of the annual ten fastest women and men were analyzed among a total of 35,956 finishes (6,862 for women and 29,094 for men) competing between 1998 and 2011 in 100-mile ultra-marathons. RESULTS: The annual top ten performances improved by 13.7% from 1,132±61.8 min in 1998 to 977.6±77.1 min in 2011 for women and by 14.5% from 959.2±36.4 min in 1998 to 820.6±25.7 min in 2011 for men. The mean ages of the annual top ten fastest runners were 39.2±6.2 years for women and 37.2±6.1 years for men. The age of peak running performance was not different between women and men (p>0.05) and showed no changes across the years. CONCLUSION: These findings indicated that the fastest female and male 100-mile ultra-marathoners improved their race time by ∼14% across the 1998–2011 period at an age when they had to be classified as master athletes. Future studies should analyze longer running distances (>200 km) to investigate whether the age of peak performance increases with increased distance in ultra-marathon running. PMID:23778421

  15. Biochemical and hematological changes following the 120-km open-water marathon swim.

    PubMed

    Drygas, Wojciech; Rębowska, Ewa; Stępień, Ewa; Golański, Jacek; Kwaśniewska, Magdalena

    2014-09-01

    Data on physiological effects and potential risks of a ultraendurance swimming are scarce. This report presents the unique case of a 61-year old athlete who completed a non-stop open-water 120-km ultramarathon swim on the Warta River, Poland. Pre-swimming examinations revealed favorable conditions (blood pressure, 110/70 mmHg; rest heart rate, 54 beats/minute, ejection fraction, 60%, 20.2 metabolic equivalents in a maximal exercise test). The swimming time and distance covered were 27 h 33 min and 120 km, respectively. Blood samples for hematological and biochemical parameters were collected 30 min, 4 hrs, 10 hrs and 8 days after the swim. The body temperature of the swimmer was 36.7°C before and 35.1°C after the swim. The hematological parameters remained within the reference range in the postexercise period except for leucocytes (17.5 and 10.6 x G/l noted 30 minutes and 4 hours after the swim, respectively). Serum urea, aspartate aminotransferase and C-reactive protein increased above the reference range reaching 11.3 mmol/l, 1054 nmol/l/s and 25.9 mg/l, respectively. Symptomatic hyponatremia was not observed. Although the results demonstrate that an experienced athlete is able to complete an ultra-marathon swim without negative health consequences, further studies addressing the potential risks of marathon swimming are required. Key pointsData on biochemical changes due to long-distance swimming are scarce.This report presents the unique case of a 61-year old athlete who completed a non-stop open-water 120-km ultramarathon swim.An experienced athlete is able to complete an ultra-marathon swim without serious health consequences.Regarding the growing popularity of marathon swimming further studies addressing the potential risks of such exhaustive exercise are required.

  16. THE RELATIONSHIP BETWEEN ISOTONIC PLANTAR FLEXOR ENDURANCE, NAVICULAR DROP, AND EXERCISE-RELATED LEG PAIN IN A COHORT OF COLLEGIATE CROSS-COUNTRY RUNNERS

    PubMed Central

    Reinking, Mark F.; Rauh, Mitchell J.

    2012-01-01

    Purpose: The purpose of this study was to examine the relationships between isotonic ankle plantar flexor endurance (PFE), foot pronation as measured by navicular drop, and exercise-related leg pain (ERLP). Background: Exercise-related leg pain is a common occurrence in competitive and recreational runners. The identification of factors contributing to the development of ERLP may help guide methods for the prevention and management of overuse injuries. Methods: Seventy-seven (44 males, 33 females) competitive runners from five collegiate cross-country (XC) teams consented to participate in the study. Isotonic ankle PFE and foot pronation were measured using the standing heel-rise and navicular drop (ND) tests, respectively. Demographic information, anthropometric measurements, and ERLP history were also recorded. Subjects were then prospectively tracked for occurrence of ERLP during the 2009 intercollegiate cross-country season. Multivariate logistic regression analysis was used to examine the relationships between isotonic ankle joint PFE and ND and the occurrence of ERLP. Results: While no significant differences were identified for isotonic ankle PFE between groups of collegiate XC runners with and without ERLP, runners with a ND >10 mm were almost 7 times (OR=6.6, 95% CI=1.2–38.0) more likely to incur medial ERLP than runners with ND <10 mm. Runners with a history of ERLP in the month previous to the start of the XC season were 12 times (OR=12.3, 95% CI=3.1–48.9) more likely to develop an in-season occurrence of ERLP. Conclusion: While PFE did not appear to be a risk factor in the development of ERLP in this group of collegiate XC runners, those with a ND greater than 10 mm may be at greater odds of incurring medial ERLP. Level of Evidence: 2b. PMID:22666641

  17. Optimal V.O2max-to-mass ratio for predicting 15 km performance among elite male cross-country skiers

    PubMed Central

    Carlsson, Tomas; Carlsson, Magnus; Hammarström, Daniel; Rønnestad, Bent R; Malm, Christer B; Tonkonogi, Michail

    2015-01-01

    The aim of this study was 1) to validate the 0.5 body-mass exponent for maximal. oxygen uptake (V.O2max) as the optimal predictor of performance in a 15 km classical-technique skiing competition among elite male cross-country skiers and 2) to evaluate the influence of distance covered on the body-mass exponent for V.O2max among elite male skiers. Twenty-four elite male skiers (age: 21.4±3.3 years [mean ± standard deviation]) completed an incremental treadmill roller-skiing test to determine their V.O2max. Performance data were collected from a 15 km classical-technique cross-country skiing competition performed on a 5 km course. Power-function modeling (ie, an allometric scaling approach) was used to establish the optimal body-mass exponent for V.O2max to predict the skiing performance. The optimal power-function models were found to be racespeed=8.83⋅(V˙O2maxm−0.53)0.66 and lapspeed=5.89⋅(V˙O2maxm−(0.49+0.0181lap))0.43e0.010age, which explained 69% and 81% of the variance in skiing speed, respectively. All the variables contributed to the models. Based on the validation results, it may be recommended that V.O2max divided by the square root of body mass (mL · min−1 · kg−0.5) should be used when elite male skiers’ performance capability in 15 km classical-technique races is evaluated. Moreover, the body-mass exponent for V.O2max was demonstrated to be influenced by the distance covered, indicating that heavier skiers have a more pronounced positive pacing profile (ie, race speed gradually decreasing throughout the race) compared to that of lighter skiers. PMID:26719730

  18. Are gender differences in upper-body power generated by elite cross-country skiers augmented by increasing the intensity of exercise?

    PubMed

    Hegge, Ann Magdalen; Myhre, Kenneth; Welde, Boye; Holmberg, Hans-Christer; Sandbakk, Øyvind

    2015-01-01

    In the current study, we evaluated the impact of exercise intensity on gender differences in upper-body poling among cross-country skiers, as well as the associated differences in aerobic capacity, maximal strength, body composition, technique and extent of training. Eight male and eight female elite skiers, gender-matched for level of performance by FIS points, carried out a 4-min submaximal, and a 3-min and 30-sec maximal all-out test of isolated upper-body double poling on a Concept2 ski ergometer. Maximal upper-body power and strength (1RM) were determined with a pull-down exercise. In addition, body composition was assessed with a DXA scan and training during the previous six months quantified from diaries. Relative to the corresponding female values (defined as 100%), the power output produced by the men was 88%, 95% and 108% higher during the submaximal, 3-min and 30-sec tests, respectively, and peak power in the pull-down strength exercise was 118% higher (all P<0.001). During the ergometer tests the work performed per cycle by the men was 97%, 102% and 91% greater, respectively, and the men elevated their cycle rate to a greater extent at higher intensities (both P<0.01). Furthermore, men had a 61% higher VO2peak, 58% higher 1RM, relatively larger upper-body mass (61% vs 56%) and reported considerably more upper-body strength and endurance training (all P<0.05). In conclusion, gender differences in upper-body power among cross-country skiers augmented as the intensity of exercise increased. The gender differences observed here are greater than those reported previously for both lower- and whole-body sports and coincided with greater peak aerobic capacity and maximal upper-body strength, relatively more muscle mass in the upper-body, and more extensive training of upper-body strength and endurance among the male skiers.

  19. Are Gender Differences in Upper-Body Power Generated by Elite Cross-Country Skiers Augmented by Increasing the Intensity of Exercise?

    PubMed Central

    Hegge, Ann Magdalen; Myhre, Kenneth; Welde, Boye; Holmberg, Hans-Christer; Sandbakk, Øyvind

    2015-01-01

    In the current study, we evaluated the impact of exercise intensity on gender differences in upper-body poling among cross-country skiers, as well as the associated differences in aerobic capacity, maximal strength, body composition, technique and extent of training. Eight male and eight female elite skiers, gender-matched for level of performance by FIS points, carried out a 4-min submaximal, and a 3-min and 30-sec maximal all-out test of isolated upper-body double poling on a Concept2 ski ergometer. Maximal upper-body power and strength (1RM) were determined with a pull-down exercise. In addition, body composition was assessed with a DXA scan and training during the previous six months quantified from diaries. Relative to the corresponding female values (defined as 100%), the power output produced by the men was 88%, 95% and 108% higher during the submaximal, 3-min and 30-sec tests, respectively, and peak power in the pull-down strength exercise was 118% higher (all P<0.001). During the ergometer tests the work performed per cycle by the men was 97%, 102% and 91% greater, respectively, and the men elevated their cycle rate to a greater extent at higher intensities (both P<0.01). Furthermore, men had a 61% higher VO2peak, 58% higher 1RM, relatively larger upper-body mass (61% vs 56%) and reported considerably more upper-body strength and endurance training (all P<0.05). In conclusion, gender differences in upper-body power among cross-country skiers augmented as the intensity of exercise increased. The gender differences observed here are greater than those reported previously for both lower- and whole-body sports and coincided with greater peak aerobic capacity and maximal upper-body strength, relatively more muscle mass in the upper-body, and more extensive training of upper-body strength and endurance among the male skiers. PMID:26000713

  20. In silico screening for novel inhibitors of DNA polymerase III alpha subunit of Mycobacterium tuberculosis (MtbDnaE2, H37Rv).

    PubMed

    Jadaun, Alka; Sudhakar D, Raja; Subbarao, N; Dixit, Aparna

    2015-01-01

    Tuberculosis, a pandemic disease is caused by Mycobacterium tuberculosis (Mtb). DNA polymerase III encoded by DnaE2 of Mtb is specifically required for its survival in vivo, and hence can be considered to be a potential drug target. Amino acid sequence analysis of the MtbDnaE2 and its human counterpart does not show any significant similarity. Therefore, a 3D model of the MtbDnaE2 was generated using Modeller 9v10 with the template structure of E. Coli DNA polymerase III alpha subunit (2HNH_A). The generated models were validated using a number of programmes such as RAMPAGE/PROCHECK, VERIFY_3D, and ProSA. MtbDnaE2 has few conserved residues and four conserved domains similar to that present in DNA polymerase III of E. coli. In silico screening was performed with bioactive anti-tuberculosis compounds and 6-AU (a known inhibitor of DNA polymerase III of Bacillus subtilis) and its analogues against the modeled MtbDnaE2 structure. Docking was performed using GOLD v5.2 software which resulted in the identification of top ten compounds with high GOLD fitness scores and binding affinity (X-Score). To further evaluate the efficacy of these compounds, in silico ADMET analysis was performed using MedChem Designer v3. Given their high binding affinity to the targeted MtbDnaE2, which is essential for DNA replication in the Mtb and good ADMET properties, these compounds are promising candidates for further evaluation and development as anti-tubercular agents.

  1. In Silico Screening for Novel Inhibitors of DNA Polymerase III Alpha Subunit of Mycobacterium tuberculosis (MtbDnaE2, H37Rv)

    PubMed Central

    Jadaun, Alka; Sudhakar D, Raja; Subbarao, N.; Dixit, Aparna

    2015-01-01

    Tuberculosis, a pandemic disease is caused by Mycobacterium tuberculosis (Mtb). DNA polymerase III encoded by DnaE2 of Mtb is specifically required for its survival in vivo, and hence can be considered to be a potential drug target. Amino acid sequence analysis of the MtbDnaE2 and its human counterpart does not show any significant similarity. Therefore, a 3D model of the MtbDnaE2 was generated using Modeller 9v10 with the template structure of E. Coli DNA polymerase III alpha subunit (2HNH_A). The generated models were validated using a number of programmes such as RAMPAGE/PROCHECK, VERIFY_3D, and ProSA. MtbDnaE2 has few conserved residues and four conserved domains similar to that present in DNA polymerase III of E. coli. In silico screening was performed with bioactive anti-tuberculosis compounds and 6-AU (a known inhibitor of DNA polymerase III of Bacillus subtilis) and its analogues against the modeled MtbDnaE2 structure. Docking was performed using GOLD v5.2 software which resulted in the identification of top ten compounds with high GOLD fitness scores and binding affinity (X-Score). To further evaluate the efficacy of these compounds, in silico ADMET analysis was performed using MedChem Designer v3. Given their high binding affinity to the targeted MtbDnaE2, which is essential for DNA replication in the Mtb and good ADMET properties, these compounds are promising candidates for further evaluation and development as anti-tubercular agents. PMID:25811866

  2. Effect of carbohydrate intake on half-marathon performance of well-trained runners.

    PubMed

    Burke, Louise M; Wood, Clare; Pyne, David B; Telford, D Richard; Saunders, Philo U

    2005-12-01

    Eighteen highly-trained runners ran two half marathons in mild environmental conditions, 3 wk apart, consuming either 426 +/- 227 mL of a flavored placebo drink (PLACEBO) or an equivalent volume of water (386 +/- 185 mL) and a commercial gel (GEL) supplying 1.1 +/- 0.2 g/kg body mass (BM) carbohydrate (CHO). Voluntary consumption of this fluid was associated with a mean BM change of approximately 2.4%. Runners performed better in their second race by 0.9% or 40 s (P = 0.03). Three runners complained of gastrointestinal discomfort in GEL trial, which produced a clear impairment of half-marathon performance by 2.4% or 105 s (P=0.03). The effect of GEL on performance was trivial: time was improvedby 0.3% or 14 s compared with PLACEBO (P = 0.52). Consuming the gel was associated with a 2.4% slower time through the 2 x 200 m feed zone; adding a trivial approximately 2 s to race time. Although benefits to half marathon performance were not detected, the theoretical improvement during 1-h exercise with CHO intake merits further investigation. PMID:16521844

  3. Cardiorespiratory demands during an inline speed skating marathon race: a case report.

    PubMed

    Stangier, Carolin; Abel, Thomas; Mierau, Julia; Hollmann, Wildor; Strüder, Heiko K

    2016-09-01

    This study was designed to investigate the intensity profile during an inline speed skating marathon road race. A highly-trained male athlete (20 y, 73.4 kg, 178 cm, V̇O2 peak: 60.8 mL·kg-1·min-1) participated in a marathon road race. Oxygen uptake (V̇O2), respiratory exchange ratio (RER), heart rate (HR) and speed were measured using a portable gas analysis system with a HR monitor and GPS-Sensor integrated. The athlete´s peak V̇O2, HR and speed at ventilatory thresholds were assessed during an incremental field test (22 km·h-1, increase 2 km·h-1 every 5 min) one week before the race. During the race, the absolute time spent in the "easy intensity zone" (V̇O2 below VT1) was 1 min, 49 min "moderate intensity zone" (V̇O2 between VT1 and VT2), and 26 min in the "hard intensity zone" (V̇O2 above VT2). The average HR was 171±6 bpm, corresponding to 95% of the maximum. This study shows that inline speed skating road races over a marathon are conducted at moderate to high V̇O2 and heart rate levels. The physiological racing pattern is very intermittent, requiring both a high level of aerobic and anaerobic capacity.

  4. Strategies to enhance immune function for marathon runners : what can be done?

    PubMed

    Akerström, Thorbjörn C A; Pedersen, Bente K

    2007-01-01

    Marathoners are at an increased risk of developing upper respiratory tract infections (URTIs) following races and periods of hard training, which are associated with temporary changes in the immune system. The majority of the reported changes are decreases in function or concentration of certain immune cells. During this period of immune suppression, by some referred to as an 'open window' in immune function, it has been hypothesised that viruses and bacteria might gain a foothold, which would increase the risk of infections. In light of this, nutritional interventions that can enhance immune function and reduce the risk of URTIs have been sought. This paper focuses on the effect of glutamine, vitamin C, bovine colostrum and glucose. Although, some of these supplements can affect the physiological and immune changes associated with marathon racing, none of the supplements discussed have consistently been shown to reduce the risk of URTIs and therefore cannot be recommended for use as enhancers of immune function in marathon runners. PMID:17465623

  5. Cardiorespiratory demands during an inline speed skating marathon race: a case report.

    PubMed

    Stangier, Carolin; Abel, Thomas; Mierau, Julia; Hollmann, Wildor; Strüder, Heiko K

    2016-09-01

    This study was designed to investigate the intensity profile during an inline speed skating marathon road race. A highly-trained male athlete (20 y, 73.4 kg, 178 cm, V̇O2 peak: 60.8 mL·kg-1·min-1) participated in a marathon road race. Oxygen uptake (V̇O2), respiratory exchange ratio (RER), heart rate (HR) and speed were measured using a portable gas analysis system with a HR monitor and GPS-Sensor integrated. The athlete´s peak V̇O2, HR and speed at ventilatory thresholds were assessed during an incremental field test (22 km·h-1, increase 2 km·h-1 every 5 min) one week before the race. During the race, the absolute time spent in the "easy intensity zone" (V̇O2 below VT1) was 1 min, 49 min "moderate intensity zone" (V̇O2 between VT1 and VT2), and 26 min in the "hard intensity zone" (V̇O2 above VT2). The average HR was 171±6 bpm, corresponding to 95% of the maximum. This study shows that inline speed skating road races over a marathon are conducted at moderate to high V̇O2 and heart rate levels. The physiological racing pattern is very intermittent, requiring both a high level of aerobic and anaerobic capacity. PMID:26745782

  6. Do women reduce the gap to men in ultra-marathon running?

    PubMed

    Knechtle, Beat; Valeri, Fabio; Nikolaidis, Pantelis T; Zingg, Matthias A; Rosemann, Thomas; Rüst, Christoph A

    2016-01-01

    The aim of the present study was to examine sex differences across years in performance of runners in ultra-marathons lasting from 6 h to 10 days (i.e. 6, 12, 24, 48, 72, 144, and 240 h). Data of 32,187 finishers competing between 1975 and 2013 with 93,109 finishes were analysed using multiple linear regression analyses. With increasing age, the sex gap for all race durations increased. Across calendar years, the gap between women and men decreased in 6, 72, 144 and 240 h, but increased in 24 and 48 h. The men-to-women ratio differed among age groups, where a higher ratio was observed in the older age groups, and this relationship varied by distance. In all durations of ultra-marathon, the participation of women and men varied by age (p < 0.001), indicating a relatively low participation of women in the older age groups. In summary, between 1975 and 2013, women were able to reduce the gap to men for most of timed ultra-marathons and for those age groups where they had relatively high participation. PMID:27350909

  7. The central governor model of exercise regulation applied to the marathon.

    PubMed

    Noakes, Timothy D

    2007-01-01

    Two popular models hold that performance during exercise is limited by chemical factors acting either in the exercising muscles or in the brain producing either 'peripheral' or 'central' fatigue, respectively. A common feature of both models is that neither allows humans to 'anticipate' what will happen in the future and modify their exercise response accordingly. The peripheral fatigue model predicts that exercise terminates only after there has been catastrophic failure in one or more body systems and only when all the available motor units in the active muscles have been activated. The marathon race provides evidence that human athletes race 'in anticipation' by setting a variable pace at the start, dependent in part on the environmental conditions and the expected difficulty of the course, with the capacity to increase that pace near the finish. Marathoners also finish such races without evidence for a catastrophic failure of homeostasis characterised by the development of a state of absolute fatigue in which all the available motor units in their active muscles are recruited. These findings are best explained by the action of a central (brain) neural control that regulates performance in the marathon 'in anticipation' specifically to prevent biological harm.

  8. Prior Design for Dependent Dirichlet Processes: An Application to Marathon Modeling

    PubMed Central

    F. Pradier, Melanie; J. R. Ruiz, Francisco; Perez-Cruz, Fernando

    2016-01-01

    This paper presents a novel application of Bayesian nonparametrics (BNP) for marathon data modeling. We make use of two well-known BNP priors, the single-p dependent Dirichlet process and the hierarchical Dirichlet process, in order to address two different problems. First, we study the impact of age, gender and environment on the runners’ performance. We derive a fair grading method that allows direct comparison of runners regardless of their age and gender. Unlike current grading systems, our approach is based not only on top world records, but on the performances of all runners. The presented methodology for comparison of densities can be adopted in many other applications straightforwardly, providing an interesting perspective to build dependent Dirichlet processes. Second, we analyze the running patterns of the marathoners in time, obtaining information that can be valuable for training purposes. We also show that these running patterns can be used to predict finishing time given intermediate interval measurements. We apply our models to New York City, Boston and London marathons. PMID:26821155

  9. On site assessment of cardiac function and neural regulation in amateur half marathon runners

    PubMed Central

    Dalla Vecchia, Laura; Traversi, Egidio; Porta, Alberto; Lucini, Daniela; Pagani, Massimo

    2014-01-01

    Objective Strenuous exercise variably modifies cardiovascular function. Only few data are available on intermediate levels of effort. We therefore planned a study in order to address the hypothesis that a half marathon distance would result in transient changes of cardiac mechanics, neural regulation and biochemical profile suggestive of a complex, integrated adaptation. Methods We enrolled 35 amateur athletes (42±7 years). Supine and standing heart rate variability and a complete echocardiographic evaluation were assessed on site after the completion of a half marathon (postrace) and about 1 month after (baseline). Biochemical tests were also measured postrace. Results Compared to baseline, the postrace left ventricular end-diastolic volume was smaller, peak velocity of E wave was lower, peak velocity of A wave higher, and accordingly the E/A ratio lower. The postrace heart and respiratory rate were higher and variance of RR interval lower, together with a clear shift towards a sympathetic predominance in supine position and a preserved response to orthostasis. At baseline, athletes were characterised by a lower, although still predominant, sympathetic drive with a preserved physiological response to standing. Conclusions Immediately after a half marathon there are clear marks that an elevated sympathetic cardiac drive outlasts the performance, together with decreased left ventricular diastolic volumes and slight modifications of the left ventricular filling pattern without additional signs of diastolic dysfunction or indices of transient left or right ventricular systolic abnormalities. Furthermore, no biochemical indices of any permanent cardiac damage were found. PMID:25332775

  10. Prior Design for Dependent Dirichlet Processes: An Application to Marathon Modeling.

    PubMed

    F Pradier, Melanie; J R Ruiz, Francisco; Perez-Cruz, Fernando

    2016-01-01

    This paper presents a novel application of Bayesian nonparametrics (BNP) for marathon data modeling. We make use of two well-known BNP priors, the single-p dependent Dirichlet process and the hierarchical Dirichlet process, in order to address two different problems. First, we study the impact of age, gender and environment on the runners' performance. We derive a fair grading method that allows direct comparison of runners regardless of their age and gender. Unlike current grading systems, our approach is based not only on top world records, but on the performances of all runners. The presented methodology for comparison of densities can be adopted in many other applications straightforwardly, providing an interesting perspective to build dependent Dirichlet processes. Second, we analyze the running patterns of the marathoners in time, obtaining information that can be valuable for training purposes. We also show that these running patterns can be used to predict finishing time given intermediate interval measurements. We apply our models to New York City, Boston and London marathons. PMID:26821155

  11. Petroleum geochemistry of Texas and Oklahoma oils from the Marathon/Ouachita fold belt

    SciTech Connect

    Curiale, J.A. )

    1991-03-01

    The Marathon uplift of west Texas and the Ouachita Mountains of Oklahoma and Arkansas comprise the surface expressions of a Paleozoic orogenic belt extending across the south-central United States. A century of petroleum exploration in the Marathon and Ouachita exposures has yielded several oil discoveries. In this study, detailed molecular, elemental, and isotopic data are presented for nine Texas oils, five Oklahoma oils, and four Oklahoma solid bitumens, all associated with thrust belt rocks of the Marathons and Ouachitas. Oil-oil and oil-solid bitumen correlations are proposed, and the character of the organic matter in the source rock(s) is deduced from the chemistry of the oils and solid bitumens. All 18 samples are sourced from the same (or very similar) organic matter. This indicates that they are probably cogenetic, despite geographic separations of hundreds of miles. Chemical differences in these samples derive from secondary effects, including biodegradation (e.g., solid bitumens) and differing levels of thermal maturity. The occurrence of unusual chemical compounds (certain bisnor- and trisnor-hopanes) in all samples probably indicates the presence of anaerobic bacteria in the depositional environment. Source deductions from oil chemistry suggest that an Ordovician unit is responsible for these oils and solid bitumens. This conclusion is consistent with previous literature suggesting an Upper Ordovician source for Oklahoma Ouachita oils and supports tectonic reconstructions of the region during Ordovician time.

  12. Xpert MTB/RIF: a New Pillar in Diagnosis of Extrapulmonary Tuberculosis?▿

    PubMed Central

    Vadwai, Viral; Boehme, Catharina; Nabeta, Pamela; Shetty, Anjali; Alland, David; Rodrigues, Camilla

    2011-01-01

    Approximately 10 to 15% of tuberculosis (TB) cases in India are estimated to have extrapulmonary disease, and due to a lack of diagnostic means, they often remain untreated. The early detection of Mycobacterium tuberculosis and multidrug resistance is a priority in TB diagnosis to improve the successful treatment rate of TB and reduce transmission. The Xpert MTB/RIF (Xpert) test, recently endorsed by the World Health Organization for the detection of pulmonary TB, was evaluated to test its utility in 547 patients with suspected extrapulmonary tuberculosis. Five hundred forty-seven extrapulmonary specimens were split and processed simultaneously for both culture (solid and liquid) and Xpert testing. For culture, the sensitivity was low, 53% (150/283 specimens). Xpert sensitivity and specificity results were assessed in comparison to a composite reference standard made up of smear and culture results and clinical, radiological, and histological findings. The sensitivity of the Xpert assay was 81% (228/283 specimens) (64% [89/138] for smear-negative cases and 96% [139/145] for smear-positive cases), with a specificity of 99.6%. The sensitivity was found to be high for the majority of specimen types (63 to 100%) except for cerebrospinal fluid, the sensitivity of which was 29% (2/7 specimens). The Xpert test correctly identified 98% of phenotypic rifampin (RIF)-resistant cases and 94% of phenotypic RIF-susceptible cases. Sequencing of the 6 discrepant samples resolved 3 of them, resulting in an increased specificity of 98%. In conclusion, the results of this study suggest that the Xpert test also shows good potential for the diagnosis of extrapulmonary TB and that its ease of use makes it applicable for countries where TB is endemic. PMID:21593262

  13. Operational lessons drawn from pilot implementation of Xpert MTB/Rif in Brazil

    PubMed Central

    Durovni, Betina; Saraceni, Valeria; Cordeiro-Santos, Marcelo; Cavalcante, Solange; Soares, Elizabeth; Lourenço, Cristina; Menezes, Alexandre; van den Hof, Susan; Cobelens, Frank

    2014-01-01

    Abstract Problem The World Health Organization has endorsed the Xpert MTB/RIF (Xpert), an automated polymerase-chain-reaction-based assay, for the rapid diagnosis of tuberculosis. However, large-scale use of a new technology calls for preparation and adaptation. Approach A pilot implementation study was conducted in two Brazilian cities to explore the replacement of sputum smear microscopy with Xpert. The laboratories included covered 70% of the tuberculosis cases diagnosed, had no overlap in population catchment areas, handled different workloads and were randomly shifted to Xpert. Sputum samples were collected through the same routine procedures. Before the study the medical information system was prepared for the recording of Xpert results. Laboratory technicians were trained to operate Xpert machines and health workers were taught how to interpret the results. Local setting The average annual tuberculosis incidence in Brazil is around 90 cases per 100 000 population. However, co-infection with the human immunodeficiency virus and multidrug resistance are relatively infrequent (10% and < 2%, respectively). Relevant changes Of the tested sputum samples, 7.3% were too scanty for Xpert and had to be examined microscopically. Ten per cent of Xpert equipment needed replacement, but spare parts were not readily available in the country. Absence of patient identification numbers led to the introduction of errors in the medical information system. Lessons learnt For nationwide scale-up, a local service provider is needed to maintain the Xpert system. Ensuring cartridge availability is also essential. The capacity to perform smear microscopy should be retained. The medical information system needs updating to allow efficient use of Xpert. PMID:25177076

  14. Evaluation of the Cobas TaqMan MTB real-time PCR assay for direct detection of Mycobacterium tuberculosis in respiratory specimens.

    PubMed

    Lee, Meng-Rui; Chung, Kuei-Pin; Wang, Hao-Chien; Lin, Chih-Bin; Yu, Chong-Jen; Lee, Jen-Jyh; Hsueh, Po-Ren

    2013-08-01

    The Cobas TaqMan MTB assay is a real-time PCR (qPCR) kit for rapid detection of Mycobacterium tuberculosis from clinical specimens. There are, however, limited studies validating its performance. We performed a prospective study in two hospitals in Taiwan on 586 respiratory specimens. By using culture as the reference method, the sensitivity and specificity of the Cobas TaqMan MTB assay were found to be 82.7 and 96.5 %, respectively. The sensitivity of the Cobas TaqMan MTB assay in acid-fast stain-negative respiratory specimens was only 34.9 %. Five specimens from five patients were positive for M. tuberculosis by the Cobas TaqMan MTB assay but were negative for M. tuberculosis by conventional culture methods. A diagnosis of pulmonary tuberculosis (TB) was made based on clinical and radiological findings as well as the response to anti-TB treatment in these five patients. Addition of data from these five specimens with discrepant results (PCR vs culture) from patients with symptoms clinically compatible with TB increased the sensitivity of the Cobas TaqMan MTB assay to 83.1 %. The Cobas TaqMan MTB assay is a rapid identification tool with a high degree of specificity for the direct detection of M. tuberculosis in respiratory specimens. The sensitivity for detecting acid-fast smear-negative respiratory specimens, however, is low.

  15. Magnetic resonance imaging of myocardial injury and ventricular torsion after marathon running.

    PubMed

    Hanssen, Henner; Keithahn, Alexandra; Hertel, Gernot; Drexel, Verena; Stern, Heiko; Schuster, Tibor; Lorang, Dan; Beer, Ambros J; Schmidt-Trucksäss, Arno; Nickel, Thomas; Weis, Michael; Botnar, Rene; Schwaiger, Markus; Halle, Martin

    2011-02-01

    Recent reports provide indirect evidence of myocardial injury and ventricular dysfunction after prolonged exercise. However, existing data is conflicting and lacks direct verification of functional myocardial alterations by CMR [cardiac MR (magnetic resonance)]. The present study sought to examine structural myocardial damage and modification of LV (left ventricular) wall motion by CMR imaging directly after a marathon. Analysis of cTnT (cardiac troponin T) and NT-proBNP (N-terminal pro-brain natriuretic peptide) serum levels, echocardiography [pulsed-wave and TD (tissue Doppler)] and CMR were performed before and after amateur marathon races in 28 healthy males aged 41 ± 5 years. CMR included LGE (late gadolinium enhancement) and myocardial tagging to assess myocardial injury and ventricular motion patterns. Echocardiography indicated alterations of diastolic filling [decrease in E/A (early transmitral diastolic filling velocity/late transmitral diastolic filling velocity) ratio and E' (tissue Doppler early transmitral diastolic filling velocity)] postmarathon. All participants had a significant increase in NT-proBNP and/or cTnT levels. However, we found no evidence of LV LGE. MR tagging demonstrated unaltered radial shortening, circumferential and longitudinal strain. Myocardial rotation analysis, however, revealed an increase of maximal torsion by 18.3% (13.1 ± 3.8 to 15.5 ± 3.6 °; P=0.002) and maximal torsion velocity by 35% (6.8 ± 1.6 to 9.2 ± 2.5 °·s-1; P<0.001). Apical rotation velocity during diastolic filling was increased by 1.23 ± 0.33 °·s-1 after marathon (P<0.001) in a multivariate analysis adjusted for heart rate, whereas peak untwist rate showed no relevant changes. Although marathon running leads to a transient increase of cardiac biomarkers, no detectable myocardial necrosis was observed as evidenced by LGE MRI (MR imaging). Endurance exercise induces an augmented systolic wringing motion of the myocardium and increased diastolic filling

  16. Do Xpert MTB/RIF Cycle Threshold Values Provide Information about Patient Delays for Tuberculosis Diagnosis?

    PubMed Central

    Ssengooba, Willy; Respeito, Durval; Mambuque, Edson; Blanco, Silvia; Bulo, Helder; Mandomando, Inacio; de Jong, Bouke C.; Cobelens, Frank G.; García-Basteiro, Alberto L.

    2016-01-01

    Introduction Early diagnosis and initiation to appropriate treatment is vital for tuberculosis (TB) control. The XpertMTB/RIF (Xpert) assay offers rapid TB diagnosis and quantitative estimation of bacterial burden through Cycle threshold (Ct) values. We assessed whether the Xpert Ct value is associated with delayed TB diagnosis as a potential monitoring tool for TB control programme performance. Materials and Methods This analysis was nested in a prospective study under the routine TB surveillance procedures of the National TB Control Program in Manhiça district, Maputo province, Mozambique. Presumptive TB patients were tested using smear microscopy and Xpert. We explored the association between Xpert Ct values and self-reported delay of Xpert-positive TB patients as recorded at the time of diagnosis enrolment. Patients with >60 days of TB symptoms were considered to have long delays. Results Of 1,483 presumptive TB cases, 580 were diagnosed as TB of whom 505 (87.0%) were due to pulmonary TB and 302 (94.1%) were Xpert positive. Ct values (range, 9.7–46.4) showed a multimodal distribution. The median (IQR) delay was 30 (30–45) days. Ct values showed no correlation with delay (R2 = 0.001, p = 0.621), nor any association with long delays: adjusted odds ratios (AOR) (95% confidence interval [CI]) comparing to >28 cycles 0.99 (0.50–1.96; p = 0.987) for 23–28 cycles, 0.93 (0.50–1.74; p = 0.828) for 16–22 cycles; and 1.05 (0.47–2.36; p = 0.897) for <16 cycles. Being HIV-negative (AOR [95% CI]), 2.05 (1.19–3.51, p = 0.009) and rural residence 1.74 (1.08–2.81, p = 0.023), were independent predictors of long delays. Conclusion Xpert Ct values were not associated with patient delay for TB diagnosis and cannot be used as an indicator of TB control program performance. PMID:27611466

  17. Evaluation of the implementation of the Xpert® MTB/RIF assay in Fiji.

    PubMed

    Gounder, A; Gounder, S; Reid, S A

    2014-09-21

    Contexte : Tous les tests Xpert® MTB/RIF réalisés dans les trois centres de traitement anti-tuberculeux aux Fidji entre juin 2012 et février 2013.Objectifs : Déterminer 1) le nombre de tests Xpert réalisés dans chaque centre, 2) l'association entre la qualité des crachats et le résultat du test Xpert, 3) l'accord entre Xpert et la microscopie des crachats acido alcoolo résistant (AFB) et la culture, et 4) le taux d'erreurs.Schéma : Revue rétrosp ective de dossiers.Résultats : Un total de 415 tests Xpert a été réalisé pendant la période d'étude. Mycobacterium tuberculosis a été détecté dans 69 (16.6%) échantillons. Aucune résistance à la rifampicine n'a été décelée. M. tuberculosis a été identifié dans 60 (18,7%) échantillons de crachats de bonne qualité. Un total de 43 (10,4%) erreurs sont survenues pendant la période d'étude. M. tuberculosis a été identifié dans 10 (2,9%) spécimens à frottis négatif. Il y a eu une concordance substantielle et presque parfaite entre les résultats du Xpert et ceux de la microscopie AFB (κ = 0,793) et de la culture (κ = 0,818), respectivement.Conclusion : En dépit de la bonne corrélation entre Xpert et les deux autres tests mise en évidence dans l'étude, Xpert ne peut toujours pas remplacer les tests de diagnostic de routine utilisés en première intention aux Fidji, en raison de contraintes logistiques et de problèmes de pérennité. Il est nécessaire de réaliser une évaluation ultérieure de la performance de ce test sur une période plus longue afin de mesurer sa valeur diagnostique dans la détection de cas à frottis négatif, Xpert positif aux Fidji.

  18. Mixed impact of Xpert(®) MTB/RIF on tuberculosis diagnosis in Cambodia.

    PubMed

    Auld, S C; Moore, B K; Kyle, R P; Eng, B; Nong, K; Pevzner, E S; Eam, K K; Eang, M T; Killam, W P

    2016-06-21

    Contexte : Sites du Programme National contre la Tuberculose (TB) dans le nord-ouest du Cambodge.Objectif : Evaluer l'impact du Xpert(®) MTB/RIF dans des sites où il est réalisé sur place (POC) comparés aux autres sites sur le diagnostic des personnes vivant avec le VIH (PVVIH) et ayant des symptômes de TB ainsi que des patients présumées de TB multirésistante (MDR).Schéma : Cohorte d'observation de patients bénéficiant d'une évaluation diagnostique de routine pour la TB après le lancement de l'Xpert.Résultats : Entre octobre 2011 et juin 2013, 431/822 (52%) PVVIH ayant des symptômes de TB et 240/493 (49%) patients avec suspicion de TB-MDR ont eu un test Xpert. L'Xpert a été réalisé plus souvent lorsqu'il était disponible en POC. Une plus faible proportion de PVVIH a eu un diagnostic de TB dans les sites POC que dans les sites non-POC ; cependant, dans les sites POC, une proportion plus élevée des patients ayant eu un diagnostic de TB a eu une bactériologie positive. L'accord entre l'Xpert et les autres tests (par exemple la microscopie de frottis ou la culture) a été médiocre. Dans l'ensemble, l'évaluation des patients présumées de TB-MDR a augmenté après le lancement de l'Xpert, mais parmi les patients ayant eu une pharmacorésistance confirmée par test de pharmacosensibilité, seulement 46% ont eu une résistance à la rifampicine qui aurait été identifiée par Xpert.Conclusion : Même si l'utilisation de l'Xpert a été faible, l'Xpert pourrait avoir contribué à une augmentation de l'évaluation des suspicions de TB-MDR et à un déclin du traitement empirique des PVVIH quand il est disponible sur place.

  19. Added value of molecular assay Xpert MTB/RIF compared to sputum smear microscopy to assess the risk of tuberculosis transmission in a low-prevalence country.

    PubMed

    Opota, O; Senn, L; Prod'hom, G; Mazza-Stalder, J; Tissot, F; Greub, G; Jaton, K

    2016-07-01

    Airborne precautions are required at hospital admission for patients with suspected pulmonary tuberculosis. The isolation is maintained until 3 serially collected sputum smears are acid-fast bacilli negative, a time- and labor-intensive method with limited sensitivity and specificity, which has a great impact on patient flow management. We evaluated the possibility of replacing the result of microscopy by the semiquantitative result of the molecular point-of-care test Xpert MTB/RIF to assess patients' transmission risk to quickly guide airborne isolation decisions in low-endemic countries. The performance of the Xpert MTB/RIF, used as a first-line test, was compared to the results of microscopy for specimens (n=242) collected from May 2010 to December 2014 in Lausanne, Switzerland. The sensitivity and specificity of Xpert MTB/RIF were 91.5% (65/71) and 99.6% (170/171), respectively, vs. 64.8% (46/71) and 94.2% (161/171) for microscopy. Samples with negative Xpert MTB/RIF were all smear negative for Mycobacterium tuberculosis (negative predictive value, 100%). The semiquantitative results of Xpert MTB/RIF-high, medium, low or very low-were found to correlate with acid-fast bacilli detection: positive predictive value of 100% (6/6), 96.5% (27/28), 52.2% (12/23) and 11.1% (1/9) respectively. Finally, when including clinical criteria, we identified 11 smear-negative but Xpert MTB/RIF-positive patients with a significant transmission potential. In conclusion, our data support the introduction of an Xpert MTB/RIF-based strategy as a replacement of smear microscopy for a faster and more accurate management of tuberculosis patients' transmission risk in a low-prevalence country. PMID:27139592

  20. Xpert®MTB/RIF for the Diagnosis of Tuberculosis in a Remote Arctic Setting: Impact on Cost and Time to Treatment Initiation

    PubMed Central

    Oxlade, Olivia; Sugarman, Jordan; Alvarez, Gonzalo G.; Pai, Madhukar; Schwartzman, Kevin

    2016-01-01

    Background Tuberculosis (TB) remains a significant health problem in the Canadian Arctic. Substantial health system delays in TB diagnosis can occur, in part due to the lack of capacity for onsite microbiologic testing. A study recently evaluated the yield and impact of a rapid automated PCR test (Xpert®MTB/RIF) for the diagnosis of TB in Iqaluit (Nunavut). We conducted an economic analysis to evaluate the expected cost relative to the expected reduction in time to treatment initiation, with the addition of Xpert®MTB/RIF to the current diagnostic and treatment algorithms used in this setting. Methods A decision analysis model compared current microbiologic testing to a scenario where Xpert®MTB/RIF was added to the current diagnostic algorithm for active TB, and incorporated costs and clinical endpoints from the Iqaluit study. Several sensitivity analyses that considered alternative use were also considered. We estimated days to TB diagnosis and treatment initiation, health system costs, and the incremental cost per treatment day gained for each individual evaluated for possible TB. Results With the addition of Xpert®MTB/RIF, costs increased while days to TB treatment initiation were reduced. The incremental cost per treatment day gained (per individual investigated for TB) was $164 (95% uncertainty range $85, $452). In a sensitivity analysis that considered hospital discharge after a single negative Xpert®MTB/RIF, the Xpert®MTB/RIF scenario was cost saving. Interpretation Adding Xpert®MTB/RIF to the current diagnostic algorithm for TB in Nunavut appears to reduce time to diagnosis and treatment at reasonable cost. It may be especially well suited to overcome some of the other logistical barriers that are unique to this and other remote communities. PMID:26990299

  1. Added value of molecular assay Xpert MTB/RIF compared to sputum smear microscopy to assess the risk of tuberculosis transmission in a low-prevalence country.

    PubMed

    Opota, O; Senn, L; Prod'hom, G; Mazza-Stalder, J; Tissot, F; Greub, G; Jaton, K

    2016-07-01

    Airborne precautions are required at hospital admission for patients with suspected pulmonary tuberculosis. The isolation is maintained until 3 serially collected sputum smears are acid-fast bacilli negative, a time- and labor-intensive method with limited sensitivity and specificity, which has a great impact on patient flow management. We evaluated the possibility of replacing the result of microscopy by the semiquantitative result of the molecular point-of-care test Xpert MTB/RIF to assess patients' transmission risk to quickly guide airborne isolation decisions in low-endemic countries. The performance of the Xpert MTB/RIF, used as a first-line test, was compared to the results of microscopy for specimens (n=242) collected from May 2010 to December 2014 in Lausanne, Switzerland. The sensitivity and specificity of Xpert MTB/RIF were 91.5% (65/71) and 99.6% (170/171), respectively, vs. 64.8% (46/71) and 94.2% (161/171) for microscopy. Samples with negative Xpert MTB/RIF were all smear negative for Mycobacterium tuberculosis (negative predictive value, 100%). The semiquantitative results of Xpert MTB/RIF-high, medium, low or very low-were found to correlate with acid-fast bacilli detection: positive predictive value of 100% (6/6), 96.5% (27/28), 52.2% (12/23) and 11.1% (1/9) respectively. Finally, when including clinical criteria, we identified 11 smear-negative but Xpert MTB/RIF-positive patients with a significant transmission potential. In conclusion, our data support the introduction of an Xpert MTB/RIF-based strategy as a replacement of smear microscopy for a faster and more accurate management of tuberculosis patients' transmission risk in a low-prevalence country.

  2. HIV/AIDS health care challenges for cross-country migrants in low- and middle-income countries: a scoping review

    PubMed Central

    Suphanchaimat, Rapeepong; Sommanustweechai, Angkana; Khitdee, Chiraporn; Thaichinda, Chompoonut; Kantamaturapoj, Kanang; Leelahavarong, Pattara; Jumriangrit, Pensom; Topothai, Thitikorn; Wisaijohn, Thunthita; Putthasri, Weerasak

    2014-01-01

    Introduction HIV/AIDS has been one of the world’s most important health challenges in recent history. The global solidarity in responding to HIV/AIDS through the provision of antiretroviral therapy (ART) and encouraging early screening has been proved successful in saving lives of infected populations in past decades. However, there remain several challenges, one of which is how HIV/AIDS policies keep pace with the growing speed and diversity of migration flows. This study therefore aimed to examine the nature and the extent of HIV/AIDS health services, barriers to care, and epidemic burdens among cross-country migrants in low-and middle-income countries. Methods A scoping review was undertaken by gathering evidence from electronic databases and gray literature from the websites of relevant international initiatives. The articles were reviewed according to the defined themes: epidemic burdens of HIV/AIDS, barriers to health services and HIV/AIDS risks, and the operational management of the current health systems for HIV/AIDS. Results Of the 437 articles selected for an initial screening, 35 were read in full and mapped with the defined research questions. A high HIV/AIDS infection rate was a major concern among cross-country migrants in many regions, in particular sub-Saharan Africa. Despite a large number of studies reported in Africa, fewer studies were found in Asia and Latin America. Barriers of access to HIV/AIDS services comprised inadequate management of guidelines and referral systems, discriminatory attitudes, language differences, unstable legal status, and financial hardship. Though health systems management varied across countries, international partners consistently played a critical role in providing support for HIV/AIDS services to uninsured migrants and refugees. Conclusion It was evident that HIV/AIDS health care problems for migrants were a major concern in many developing nations. However, there was little evidence suggesting if the current

  3. Contribution of Upper-Body Strength, Body Composition, and Maximal Oxygen Uptake to Predict Double Poling Power and Overall Performance in Female Cross-Country Skiers.

    PubMed

    Østerås, Sindre; Welde, Boye; Danielsen, Jørgen; van den Tillaar, Roland; Ettema, Gertjan; Sandbakk, Øyvind

    2016-09-01

    Østerås, S, Welde, B, Danielsen, J, van den Tillaar, R, Ettema, G, and Sandbakk, Ø. Contribution of upper-body strength, body composition, and maximal oxygen uptake to predict double poling power and overall performance in female cross-country skiers. J Strength Cond Res 30(9): 2557-2564, 2016-Maximal oxygen uptake (V[Combining Dot Above]O2max) is regarded as the most performance-differentiating physiological measure in cross-country (XC) skiing. In addition, upper-body strength and lean mass have been associated with double poling (DP) power in XC skiers. In this study, we tested upper-body maximal strength, lean mass, and V[Combining Dot Above]O2max's contributions to predict DP power production of different durations and the overall XC skiing performance level of elite female XC skiers. Thirteen skiers (V[Combining Dot Above]O2max: 64.9 ± 4.2 ml·kg·min) performed one 30-second and one 3-minute DP performance test using a ski ergometer. The International Ski Federation's (FIS) ranking points determined their overall XC skiing performance. The skiers performed three 1-repetition maximal strength tests in poling-specific exercises that isolated the elbow extension, shoulder extension, and trunk flexion movements. Body composition was determined by a DXA scan, and V[Combining Dot Above]O2max was tested in an incremental running test. Multiple regressions were used to predict power production in the 30-second and 3-minute tests and FIS points. The 2 best predictions of 30-second DP power were lean upper-body mass and maximal upper-body strength (with the 3 strength tests normalized and pooled together as one variable) (R = 0.84 and 0.81, p < 0.001). Along with V[Combining Dot Above]O2max, the same 2 variables were the best predictions of both 3-minute DP power (R = 0.60 and 0.44, p ≤ 0.05) and overall XC skiing performance (R = 0.43 and 0.40, p ≤ 0.05). Although the importance of upper-body strength and lean mass to predict DP power production and the

  4. A Comparison of Anthropometric and Training Characteristics between Female and Male Half-Marathoners and the Relationship to Race Time

    PubMed Central

    Friedrich, Miriam; Rüst, Christoph A.; Rosemann, Thomas; Knechtle, Patrizia; Barandun, Ursula; Lepers, Romuald; Knechtle, Beat

    2013-01-01

    Purpose Lower limb skin-fold thicknesses have been differentially associated with sex in elite runners. Front thigh and medial calf skin-fold appear to be related to 1,500m and 10,000m time in men but 400m time in women. The aim of the present study was to compare anthropometric and training characteristics in recreational female and male half-marathoners. Methods The association between both anthropometry and training characteristics and race time was investigated in 83 female and 147 male recreational half marathoners using bi- and multi-variate analyses. Results In men, body fat percentage (β=0.6), running speed during training (β=-3.7), and body mass index (β=1.9) were related to half-marathon race time after multi-variate analysis. After exclusion of body mass index, r2 decreased from 0.51 to 0.49, but body fat percentage (β=0.8) and running speed during training (β=-4.1) remained predictive. In women, body fat percentage (β=0.75) and speed during training (β=-6.5) were related to race time (r2=0.73). For women, the exclusion of body mass index had no consequence on the predictive variables for half-marathon race time. Conclusion To summarize, in both female and male recreational half-marathoners, both body fat percentage and running speed during training sessions were related to half-marathon race times when corrected with co-variates after multi-variate regression analyses. PMID:24868427

  5. Sex differences in 24-hour ultra-marathon performance - A retrospective data analysis from 1977 to 2012

    PubMed Central

    Peter, Laura; Rüst, Christoph Alexander; Knechtle, Beat; Rosemann, Thomas; Lepers, Romuald

    2014-01-01

    OBJECTIVES: This study examined the changes in running performance and the sex differences between women and men in 24-hour ultra-marathons held worldwide from 1977 to 2012. METHOD: Changes in running speed and ages of the fastest 24-hour ultra-marathoners were determined using single- and multi-level regression analyses. RESULTS: From 1977 to 2012, the sex differences in 24-hour ultra-marathon performance were 4.6±0.5% for all women and men, 13.3% for the annual fastest finishers, 12.9±0.8% for the top 10 and 12.2±0.4% for the top 100 finishers. Over time, the sex differences decreased for the annual fastest finishers to 17%, for the annual 10 fastest finishers to 11.3±2.2% and for the annual 100 fastest finishers to 14.2±1.8%. For the annual fastest men, the age of peak running speed increased from 23 years (1977) to 53 years (2012). For the annual 10 and 100 fastest men, the ages of peak running speed were unchanged at 40.9±2.5 and 44.4±1.1 years, respectively. For women, the ages of the annual fastest, the annual 10 fastest and the annual 100 fastest remained unchanged at 43.0±6.1, 43.2±2.6 and 43.8±0.8 years, respectively. CONCLUSION: The gap between the annual top, annual top 10 and annual top 100 female and male 24-hour ultra-marathoners decreased over the last 35 years; however, it seems unlikely that women will outrun men in 24-hour ultra-marathons in the near future. The fastest 24-hour ultra-marathoners worldwide achieved their peak performance at the age of master athletes (>35 years). PMID:24473558

  6. Opportunity, Geologic and Structural Context of Aqueous Alteration in Noachian Outcrops, Marathon Valley and Rim and Endeavour Crater

    NASA Technical Reports Server (NTRS)

    Crumpler, L. S.; Arvidson, R. E.; Mittlefehldt, D. W.; Jolliff, B. L.; Farrand, W. H.; Fox, V.; Golombek, M. P.

    2016-01-01

    In its 12th year of exploration and 1600 sols since arrival at the rim of the 22 km-diameter Noachian Endeavour impact crater, Mars Exploration Rover Opportunity traversed from the summit of the western rim segment "Cape Tribulation" to "Marathon Valley", a shallow trough dissecting the rim and the site of strong orbital detection of smectites. In situ analysis of the exposures within Marathon Valley is establishing some of the geologic and geochemical controls on the aqueous alteration responsible for smectite detection known to occur in crater rims throughout Noachian terrains of Mars.

  7. How Hinge Positioning in Cross-Country Ski Bindings Affect Exercise Efficiency, Cycle Characteristics and Muscle Coordination during Submaximal Roller Skiing

    PubMed Central

    Bolger, Conor M.; Sandbakk, Øyvind; Ettema, Gertjan; Federolf, Peter

    2016-01-01

    The purposes of the current study were to 1) test if the hinge position in the binding of skating skis has an effect on gross efficiency or cycle characteristics and 2) investigate whether hinge positioning affects synergistic components of the muscle activation in six lower leg muscles. Eleven male skiers performed three 4-min sessions at moderate intensity while cross-country ski-skating and using a klapskate binding. Three different positions were tested for the binding’s hinge, ranging from the front of the first distal phalange to the metatarsal-phalangeal joint. Gross efficiency and cycle characteristics were determined, and the electromyographic (EMG) signals of six lower limb muscles were collected. EMG signals were wavelet transformed, normalized, joined into a multi-dimensional vector, and submitted to a principle component analysis (PCA). Our results did not reveal any changes to gross efficiency or cycle characteristics when altering the hinge position. However, our EMG analysis found small but significant effects of hinge positioning on muscle coordinative patterns (P < 0.05). The changed patterns in muscle activation are in alignment with previously described mechanisms that explain the effects of hinge positioning in speed-skating klapskates. Finally, the within-subject results of the EMG analysis suggested that in addition to the between-subject effects, further forms of muscle coordination patterns appear to be employed by some, but not all participants. PMID:27203597

  8. The impact of health care resources, socioeconomic status, and demographics on life expectancy: a cross-country study in three Southeast Asian countries.

    PubMed

    Chan, Moon Fai

    2015-03-01

    This study aimed to examine the impact of health care resources, socioeconomic status, and demographic changes on life expectancy in Indonesia, Philippines, and Vietnam. This was a cross-country study to collect annual data (1980-2008) from each target country. Life expectancy was the dependent variable and health care resources, socioeconomic status, and demographics were the 3 main determinants. Structural equation modeling was employed, and the results indicate that the availability of more health care resources (Indonesia: coefficient = .47, P = .008; Philippines: coefficient = .48, P = .017; Vietnam: coefficient = .48, P = .004) and higher levels of socioeconomic advantages (Indonesia: coefficient = .41, P = .014; Vietnam: coefficient = .34, P = .026) are more likely to increase life expectancy. In contrast, demographic changes are more likely to increase life expectancy because of the wide range of health care resources. These findings suggest that more effort, particularly during economic downturns, should be put into removing the barriers that impede access to health care services and increasing preventive care for the population that currently has less access to health care in communities where there is a shortage of medical resources.

  9. How Hinge Positioning in Cross-Country Ski Bindings Affect Exercise Efficiency, Cycle Characteristics and Muscle Coordination during Submaximal Roller Skiing.

    PubMed

    Bolger, Conor M; Sandbakk, Øyvind; Ettema, Gertjan; Federolf, Peter

    2016-01-01

    The purposes of the current study were to 1) test if the hinge position in the binding of skating skis has an effect on gross efficiency or cycle characteristics and 2) investigate whether hinge positioning affects synergistic components of the muscle activation in six lower leg muscles. Eleven male skiers performed three 4-min sessions at moderate intensity while cross-country ski-skating and using a klapskate binding. Three different positions were tested for the binding's hinge, ranging from the front of the first distal phalange to the metatarsal-phalangeal joint. Gross efficiency and cycle characteristics were determined, and the electromyographic (EMG) signals of six lower limb muscles were collected. EMG signals were wavelet transformed, normalized, joined into a multi-dimensional vector, and submitted to a principle component analysis (PCA). Our results did not reveal any changes to gross efficiency or cycle characteristics when altering the hinge position. However, our EMG analysis found small but significant effects of hinge positioning on muscle coordinative patterns (P < 0.05). The changed patterns in muscle activation are in alignment with previously described mechanisms that explain the effects of hinge positioning in speed-skating klapskates. Finally, the within-subject results of the EMG analysis suggested that in addition to the between-subject effects, further forms of muscle coordination patterns appear to be employed by some, but not all participants.

  10. The efficiency of health care production in OECD countries: A systematic review and meta-analysis of cross-country comparisons.

    PubMed

    Varabyova, Yauheniya; Müller, Julia-Maria

    2016-03-01

    There has been an ongoing interest in the analysis and comparison of the efficiency of health care systems using nonparametric and parametric applications. The objective of this study was to review the current state of the literature and to synthesize the findings on health system efficiency in OECD countries. We systematically searched five electronic databases through August 2014 and identified 22 studies that analyzed the efficiency of health care production at the country level. We summarized these studies with view on their sample, methods, and utilized variables. We developed and applied a checklist of 14 items to assess the quality of the reviewed studies along four dimensions: reporting, external validity, bias, and power. Moreover, to examine the internal validity of findings we meta-analyzed the efficiency estimates reported in 35 models from ten studies. The qualitative synthesis of the literature indicated large differences in study designs and methods. The meta-analysis revealed low correlations between country rankings suggesting a lack of internal validity of the efficiency estimates. In conclusion, methodological problems of existing cross-country comparisons of the efficiency of health care systems draw into question the ability of these comparisons to provide meaningful guidance to policy-makers.

  11. Natural Killer cell activation distinguishes M. tuberculosis-mediated Immune reconstitution syndrome (IRIS) from chronic HIV and HIV-MTB co-infection

    PubMed Central

    Conradie, F.; Foulkes, A.S.; Ive, P.; Yin, X.; Roussos, K.; Glencross, D.K.; Lawrie, D.; Stevens, W.; Montaner, L.J.; Sanne; Azzoni, L.

    2011-01-01

    Background With increased access to antiretroviral treatment (ART), Immune Reconstitution Inflammatory Syndrome (IRIS) in Mycobacterium tuberculosis (MTB)-infected populations remains a clinical challenge. We studied a cross-sectional cohort of HIV-infected subjects in Johannesburg (South Africa) to help define the immune correlates that best distinguish IRIS from ongoing MTB cases. Methods We studied HIV+ subjects developing MTB-related unmasking IRIS (u-TB-IRIS) after ART initiation; control groups were HIV subjects and HIV-TB co-infected subjects with comparable ART treatment. Testing was conducted with whole blood-based 4-color flow cytometry and plasma-based Luminex cytokine assessment. Results NK cell activation, C-reactive protein and IL-8 serum concentration were significantly higher in u-TB-IRIS subjects as compared to both control groups. In addition, all MTB co-infected subjects, independent of clinical presentation, had higher neutrophils and T cell activation, together with lower lymphocytes, CD4+ T cell and myeloid DC counts. Using conditional inference tree analysis we show that elevated NK cell activation in combination with lymphocyte count characterizes the immunological profile of u-TB-IRIS. Conclusions Our results support a role for innate immune effectors in the immunopathogenesis of unmasking MTB-related IRIS, and identify new immune parameters defining this pathology. PMID:21826013

  12. Regulation of electrolyte and fluid metabolism in multi-stage ultra-marathoners.

    PubMed

    Knechtle, B; Knechtle, P; Rüst, C A; Gnädinger, M; Imoberdorf, R; Kohler, G; Rosemann, T; Ballmer, P

    2012-11-01

    The purposes of this study were (i) to determine the prevalence of exercise-associated hyponatremia (EAH) in multi-stage ultra-marathoners and (ii) to gain more insight into fluid and electrolyte regulation during a multi-stage race. Body mass, sodium concentration ([Na⁺]), potassium concentration ([K⁺]), creatinine, urea, specific gravity, and osmolality in urine were measured in 25 male ultra-marathoners in the 'Swiss Jura Marathon' 2008 with 11,000 m gain of altitude over 7 stages covering 350 km, before and after each stage. Haemoglobin, haematocrit, creatinine, urea, [Na⁺], [K⁺], and osmolality were measured in plasma before stage 1 and after stages 1, 3, 5, and 7. Two athletes (8%) showed plasma [Na⁺] <135 mmol/l. Body mass, plasma [Na⁺], and plasma [K⁺] remained unchanged (p>0.05). Urine specific gravity (p<0.001) and osmolality in both plasma (p<0.01) and urine (p<0.001) were increased and haematocrit (p<0.0001), haemoglobin (p<0.0001) and plasma albumin were decreased (p<0.001). Plasma volume (p<0.01) and plasma urea (p<0.001) were increased. The K⁺/Na⁺ ratio in urine increased >1.0 after each stage and returned to <1.0 the morning of the next stage (p<0.001). To summarize, more sodium than potassium was excreted during rest. The increased urinary sodium losses during rest are compatible with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) or the cerebral salt-wasting syndrome (CSWS). Further studies are needed to determine the antidiuretic hormone (ADH) and both the atrial natriuretic peptide (ANP) and the brain natriuretic peptide (BNP) during multi-stage races.

  13. Regulation of electrolyte and fluid metabolism in multi-stage ultra-marathoners.

    PubMed

    Knechtle, B; Knechtle, P; Rüst, C A; Gnädinger, M; Imoberdorf, R; Kohler, G; Rosemann, T; Ballmer, P

    2012-11-01

    The purposes of this study were (i) to determine the prevalence of exercise-associated hyponatremia (EAH) in multi-stage ultra-marathoners and (ii) to gain more insight into fluid and electrolyte regulation during a multi-stage race. Body mass, sodium concentration ([Na⁺]), potassium concentration ([K⁺]), creatinine, urea, specific gravity, and osmolality in urine were measured in 25 male ultra-marathoners in the 'Swiss Jura Marathon' 2008 with 11,000 m gain of altitude over 7 stages covering 350 km, before and after each stage. Haemoglobin, haematocrit, creatinine, urea, [Na⁺], [K⁺], and osmolality were measured in plasma before stage 1 and after stages 1, 3, 5, and 7. Two athletes (8%) showed plasma [Na⁺] <135 mmol/l. Body mass, plasma [Na⁺], and plasma [K⁺] remained unchanged (p>0.05). Urine specific gravity (p<0.001) and osmolality in both plasma (p<0.01) and urine (p<0.001) were increased and haematocrit (p<0.0001), haemoglobin (p<0.0001) and plasma albumin were decreased (p<0.001). Plasma volume (p<0.01) and plasma urea (p<0.001) were increased. The K⁺/Na⁺ ratio in urine increased >1.0 after each stage and returned to <1.0 the morning of the next stage (p<0.001). To summarize, more sodium than potassium was excreted during rest. The increased urinary sodium losses during rest are compatible with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) or the cerebral salt-wasting syndrome (CSWS). Further studies are needed to determine the antidiuretic hormone (ADH) and both the atrial natriuretic peptide (ANP) and the brain natriuretic peptide (BNP) during multi-stage races. PMID:22638835

  14. Pre-race dietary carbohydrate intake can independently influence sub-elite marathon running performance.

    PubMed

    Atkinson, G; Taylor, C E; Morgan, N; Ormond, L R; Wallis, G A

    2011-08-01

    We examined whether selected anthropometric and nutritional factors influenced field-based marathon running performance. An internet-based data collection tool allowed competitors in the 2009 London Marathon (n=257, mean ± SD age: 39 ± 8 years, finish time: 273.8 ± 59.5 min) to record a range of anthropometric, training and nutritional predictors. Multivariate statistical methods were used to quantify the change in running speed mediated by a unit change in each predictor via the 95% confidence interval for each covariate-controlled regression slope ( B). Gender ( B=1.22 to 1.95 km/h), body mass index ( B=-0.14 to -0.27 km/h), training distance ( B=0.01 to 0.04 km/h) and the amount of carbohydrate consumed the day before the race ( B=0.08 to 0.26 km/h) were significant predictors, collectively accounting for 56% of the inter-individual variability in running speed (P<0.0005). Further covariate-adjusted analysis revealed that those competitors who consumed carbohydrate the day before the race at a quantity of >7 g/kg body mass had significantly faster overall race speeds (P=0.01) and maintained their running speed during the race to a greater extent than with those who consumed <7 g/kg body mass (P=0.02). We conclude that, in addition to gender, body size and training, pre-race day carbohydrate intake can significantly and independently influence marathon running performance.

  15. The University of California Institute of Environmental Stress marathon field studies.

    PubMed

    Maron, Michael B

    2014-03-01

    In 1973, the Institute of Environmental Stress of the University of California-Santa Barbara, under the direction of Steven M. Horvath, began a series of field and laboratory studies of marathon runners during competition. As one of Horvath's graduate students, many of these studies became part of my doctoral dissertation. The rationale for studying runners under race conditions was based on my belief as a marathoner that runners would push themselves much harder while competing than under simulated conditions in the laboratory. Horvath's ready support of the studies likely had its roots in his graduate training at the Harvard Fatigue Laboratory, a laboratory well known for its field studies of individuals working in extreme environments. This report describes the studies of 1973-1975, focusing on how the measurements were made and detailing the learning experiences of a new graduate student. In 1973, blood chemistry and fluid shifts were studied in six runners before and for 3 days after a race. This was the first modern study to systematically examine the recovery process. In 1974, oxygen consumption was measured every 3 mi. in two runners during the race. In 1975, rectal temperature and five skin temperatures were evaluated in the same two runners every 1.4 mi. of the race. The latter two studies were the first to make such measurements under race conditions. The Institute of Environmental Stress marathon studies demonstrated the possibility of making measurements during competition without disrupting performance, enhanced our understanding of human exercise capacity under competitive conditions, and provided new insight into the postrace recovery process.

  16. Anthropometric Characteristics of Chinese Professional Female Marathoners and Predicted Variables for Their Personal Bests.

    PubMed

    Yang, Xian-Gang; Wang, Yang; Bao, Da-Peng; Hu, Yang

    2015-12-01

    To investigate anthropometric characteristics of Chinese professional female marathoners and suitable predicted variables correlated with their personal bests (PB), 96 Chinese female long-distance runners were divided into international (< 2 h 34 min), national (2 h 34 min~2 h 45 min) and average (2 h 45 min~3 h 19 min) levels according to their PB in marathon during the process of talent identification for London Olympic Games. Selected anthropometric variables, including height, body mass, percentages of body fat, girths, breadths, lengths and skin-folds were measured. Only iliac crest skin-fold of international athletes was significantly lower than it is in national group. Girth of forearm and lower limbs, length of lower limbs, and all skin-folds of national athletes were significantly lower than those from average level group. Percentages of body fat, girth of forearm and calf, length of lower limbs, and skin-folds at sites of subscapular, abdominal and iliac crest of athletes from average level group were significantly higher than those in international athletes. Positive correlation was found between forearm girth and PB, and between the subscapular, abdominal, iliac crest and triceps surae skin-folds and PB for total athletes. Negative correlation between biiliac breadth and PB in international athletes, and positive correlations between abdominal and triceps surae skin-folds and PB in national athletes were found. For average runners, high positive correlation was found between upper arm girth and PB, and between subscapular, abdominal, iliac crest and triceps surae skin-folds and PB. The findings suggested that compared to stride length, stride frequency and efficiency were more important factors influencing running performance, which were in accordance with running technique in Chinese female marathoners. PMID:26987158

  17. CFTR genotype-related body water and electrolyte balance during a marathon.

    PubMed

    Del Coso, J; Lara, B; Salinero, J J; Areces, F; Ruiz-Vicente, D; Gallo-Salazar, C; Abián-Vicén, J; Cacabelos, R

    2016-09-01

    The aim of this investigation was to determine the influence of CFTR genotype on body water and electrolyte balance during a marathon. Fifty-one experienced runners completed a marathon race. Before and after the race, body mass and a sample of venous blood were obtained. During the race, sweat samples were collected using sweat patches, and fluid and electrolyte intake were obtained using self-reported questionnaires. Thirty-eight participants (74.5% of the total) were 7T/7T homozygotes, 11 (21.6%) were 7T/9T heterozygotes, and one participant presented the rare genotype 5T/7T. Another participant with 9T/9T presented the mutation p.L206W. Participants with 7T/7T showed higher sweat sodium concentrations (42.2 ± 21.6 mmol/L) than 7T/9T (29.0 ± 24.7 mmol/L; P = 0.04). The runner with the 5T/7T genotype (10.2 mmol/L) and the participant with the p.L206W mutation (20.5 mmol/L) exhibited low-range sweat sodium concentrations. However, post-race serum sodium concentration was similar in 7T/7T and 7T/9T (142.1 ± 1.3 and 142.4 ± 1.6 mmol/L, respectively; P = 0.27) and did not show abnormalities in participants with the 5T/7T genotype (140.0 mmol/L) and the p.L206W mutation (143.0 mmol/L). Runners with the CFTR-7T/7T genotype exhibited increased sweat sodium concentrations during a marathon. However, this phenotype was not related with increased likelihood of suffering body water and electrolyte imbalances during real competitions.

  18. Structure of the Mycobacterium tuberculosis Flavin Dependent Thymidylate Synthase (MtbThyX) at 2.0 Å Resolution

    SciTech Connect

    Sampathkumar, Parthasarathy; Turley, Stewart; Ulmer, Jonathan E.; Rhie, Ho Gun; Hopkins Sibley, Carol; Hol, Wim G.J.

    2010-07-20

    A novel flavin-dependent thymidylate synthase was identified recently as an essential gene in many archaebacteria and some pathogenic eubacteria. This enzyme, ThyX, is a potential antibacterial drug target, since humans and most eukaryotes lack the thyX gene and depend upon the conventional thymidylate synthase (TS) for their dTMP requirements. We have cloned and overexpressed the thyX gene (Rv2754c) from Mycobacterium tuberculosis in Escherichia coli. The M. tuberculosis ThyX (MtbThyX) enzyme complements the E. coli {chi}2913 strain that lacks its conventional TS activity. The crystal structure of the homotetrameric MtbThyX was determined in the presence of the cofactor FAD and the substrate analog, 5-bromo-2'-deoxyuridine-5'-monophosphate (BrdUMP). In the active site, which is formed by three monomers, FAD is bound in an extended conformation with the adenosine ring in a deep pocket and BrdUMP in a closed conformation near the isoalloxazine ring. Structure-based mutational studies have revealed a critical role played by residues Lys165 and Arg168 in ThyX activity, possibly by governing access to the carbon atom to be methylated of a totally buried substrate dUMP.

  19. Rhythm Analyses Of Melodies Used To Obtain Women Marathon Gold Medal

    NASA Astrophysics Data System (ADS)

    Tacano, Munecazu; Yokokura, Saburo; Kajiwara, Yoko; Pavelka, Jan; Tanuma, Nobuhisa; Uemura, Tatsuhisa; Hashiguchi, Sumihisa; Sikula, Josef

    2005-11-01

    In Athena Olympics in 2004 a Japanese girl got the gold medal in Women Marathon games. Just before the beginning, she was listening to some domestic melodies in order to concentrate on the race. The rhythm or power of that music is found to have the typical 1/f noise characteristics. The 1/f music is found effective to concentrate as well as to relax themselves for a fairly long time range, while some short time trial runner uses a kind of white noise like music.

  20. Compositions of Diverse Noachian Lithologies at Marathon Valley, Endeavour Crater Rim, Mars

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Gellert, Ralf; Yen, Albert S.; Ming, Douglas W.; Van Bommel, Scott; Farrand, William H.; Arvidson, Raymond E.; Rice, James W., Jr.

    2015-01-01

    Mars Exploration Rover Opportunity has been exploring Meridiani Planum for 11+ years, and is presently investigating the geology of rim segments of 22 km diameter, Noachian-aged Endeavour crater. The Alpha Particle X-ray Spectrometer has determined the compositions of a pre-impact lithology and impact breccias representing ejecta from the crater. Opportunity is now investigating the head (higher elevation, western end) of Marathon Valley. This valley cuts eastward through the central portion of the Cape Tribulation rim segment and provides a window into the lower stratigraphic record of the rim. At the head of Marathon Valley is a shallow (few 10s of cm), ovoid depression approximately 27×36 m in size, named Spirit of Saint Louis, that is surrounded by approximately 20-30 cm wide zone of more reddish rocks (red zone). Opportunity has just entered a region of Marathon Valley that shows evidence for Fe-Mg smectite in Compact Reconnaissance Imaging Spectrometer for Mars spectra indicating areally extensive and distinct lithologic units and/or styles of aqueous alteration. Rocks at the head of Marathon Valley and within Spirit of Saint Louis are breccias (valley-head rocks). In some areas, layering inside Spirit of Saint Louis appears continuous with the rocks outside. The valley-head rocks are of similar, generally basaltic composition. The continuity in composition, texture and layering suggest the valley-head rocks are coeval breccias, likely from the Endeavour impact. These local breccias are similar in non-volatile-element composition to breccias investigated elsewhere on the rim. Rocks within the red zone are like those on either side in texture, but have higher Al, Si and Ge, and lower S, Mn, Fe, Ni and Zn as compared to rocks on either side. The valley-head rocks have higher S than most Endeavour rim breccias, while red zone rocks are like those latter breccias in S. Patches within the rocks outside Spirit of Saint Louis have higher Al, Si and Ge indicating

  1. [Hyponatremic encephalopathy with non-cardiogenic pulmonary edema. Development following marathon run].

    PubMed

    Wellershoff, G

    2013-04-01

    This article presents the case of a 52-year-old woman who developed exercise-associated hyponatremia (EAH) complicated by non-cardiogenic pulmonary edema after a marathon run. The condition of EAH is a potentially life-threatening complication of endurance exercise. The main cause seems to be inadequate intake of free water during or following exercise with enduring antidiuresis due to nonosmotic stimulation of ADH secretion. Known risk factors are female gender, slow running pace and lack of weight loss. Emergency therapy is fluid restriction and bolus infusion of 3% NaCl solution to rapidly reduce brain edema. PMID:23381723

  2. Effects of running the Bostom Marathon on plasma concentrations of large neutral amino acids

    NASA Technical Reports Server (NTRS)

    Conlay, L. A.; Wurtman, R. J.; Lopez G-Coviella, I.; Blusztajn, J. K.; Vacanti, C. A.; Logue, M.; During, M.; Caballero, B.; Maher, T. J.; Evoniuk, G.

    1989-01-01

    Plasma large neutral amino acid concentrations were measured in thirty-seven subjects before and after completing the Boston Marathon. Concentrations of tyrosine, phenylalanine, and methionine increased, as did their 'plasma ratios' (i.e., the ratio of each amino acid's concentration to the summed plasma concentrations of the other large neutral amino acids which compete with it for brain uptake). No changes were noted in the plasma concentrations of tryptophan, leucine, isoleucine, nor valine; however, the 'plasma ratios' of valine, leucine, and isoleucine all decreased. These changes in plasma amino acid patterns may influence neurotransmitter synthesis.

  3. Comparison of AdvanSure TB/NTM PCR and COBAS TaqMan MTB PCR for Detection of Mycobacterium tuberculosis Complex in Routine Clinical Practice.

    PubMed

    Cho, Won-Hyung; Won, Eun-Jeong; Choi, Hyun-Jung; Kee, Seung-Jung; Shin, Jong-Hee; Ryang, Dong-Wook; Suh, Soon-Pal

    2015-05-01

    The AdvanSure tuberculosis/non-tuberculous mycobacterium (TB/NTM) PCR (LG Life Science, Korea) and COBAS TaqMan Mycobacterium tuberculosis (MTB) PCR (Roche Diagnostics, USA) are commonly used in clinical microbiology laboratories. We aimed to evaluate these two commercial real-time PCR assays for detection of MTB in a large set of clinical samples over a two-year period. AdvanSure TB/NTM PCR and COBAS TaqMan MTB PCR were performed on 9,119 (75.2%) and 3,010 (24.8%) of 12,129 (9,728 respiratory and 2,401 non-respiratory) MTB specimens, with 361 (4.0%) and 102 (3.4%) acid-fast bacilli (AFB)-positive results, respectively. In MTB culture, 788 (6.5%) MTB and 514 (4.2%) NTM were identified. The total sensitivity and specificity of the AdvanSure assay were 67.8% (95% confidence interval [CI], 63.9-71.6) and 98.3% (95% CI, 98.0-98.6), while those of the COBAS TaqMan assay were 67.2% (95% CI, 60.0-73.8) and 98.4% (95% CI, 97.9-98.9), respectively. The sensitivities and specificities of the AdvanSure and COBAS TaqMan assays for AFB-positive and AFB-negative samples were comparable. Furthermore, the AdvanSure assay showed fewer invalid results compared with the COBAS TaqMan assay (5.0 vs. 20.4 invalid results/1,000 tests, P<0.001). AdvanSure assay represents a comparable yet more reliable method than COBAS TaqMan for the identification of mycobacteria in routine clinical microbiology.

  4. VNIR Multispectral Observations of Rocks at Spirit of St. Louis Crater and Marathon Valley on Th Rim of Endeavour Crater Made by the Opportunity Rover Pancam

    NASA Technical Reports Server (NTRS)

    Farrand, W. H.; Johnson, J. R.; Bell, J. F., III; Mittlefehldt, D.W.

    2016-01-01

    The Mars Exploration Rover Opportunity has been exploring the western rim of the 22 km diameter Endeavour crater since August, 2011. Recently, Opportunity has reached a break in the Endeavour rim that the rover team has named Mara-thon Valley. This is the site where orbital observations from the MRO CRISM imaging spectrometer indicated the presence of iron smectites. On the outer western portion of Marathon Valley, Opportunity explored the crater-form feature dubbed Spirit of St. Louis (SoSL) crater. This presentation describes the 430 to 1009 nm (VNIR) reflectance, measured by the rover's Pancam, of rock units present both at Spirit of St. Louis and within Marathon Valley.

  5. Effect of compression stockings on physiological responses and running performance in division III collegiate cross-country runners during a maximal treadmill test.

    PubMed

    Rider, Brian C; Coughlin, Adam M; Hew-Butler, Tamara D; Goslin, Brian R

    2014-06-01

    There is a growing trend for runners to use compression stockings (CS) to improve performance. The purpose of this study was to determine the effect of CS on physiological variables associated with running performance. Participants were 10 NCAA division III cross-country runners. The study used a randomized, crossover design with 2 conditions (with CS and without CS). Both conditions consisted of a maximal treadmill test that involved 3-minute stages of increasing speed and incline, separated by a minute and one-half walking recovery stage. Seven days later, the participants repeated the maximal test but switched CS condition. Heart rate, blood lactate (BLa), blood lactate threshold, maximal oxygen consumption (VO2max), respiratory exchange ratio, rating of perceived exertion, and time to fatigue were measured. Before and during the maximal treadmill tests, the variables showed no significant difference (p ≤ 0.05) between the CS conditions. Blood lactate was lower while wearing CS when measured during recovery at the 1-minute (CS = 13.3 ± 2.9 mmol · L(-1), non-CS = 14.8 ± 2.8 mmol · L(-1), p = 0.03) and the 5-minute (CS = 11.0 ± 2.7 mmol · L(-1), non-CS = 12.8 ± 2.8 mmol · L(-1), p = 0.02) periods. Time to fatigue was longer without CS (CS = 23.570 ± 2.39 minutes, non-CS = 23.93 ± 2.49 minutes, p = 0.04). These findings suggest that CS may not improve running performance, but could lend credence to certain manufacturers' claims of improved recovery through lower BLa values after exercise.

  6. Comparing results of an exact vs. an approximate (Bayesian) measurement invariance test: a cross-country illustration with a scale to measure 19 human values.

    PubMed

    Cieciuch, Jan; Davidov, Eldad; Schmidt, Peter; Algesheimer, René; Schwartz, Shalom H

    2014-01-01

    One of the most frequently used procedures for measurement invariance testing is the multigroup confirmatory factor analysis (MGCFA). Muthén and Asparouhov recently proposed a new approach to test for approximate rather than exact measurement invariance using Bayesian MGCFA. Approximate measurement invariance permits small differences between parameters otherwise constrained to be equal in the classical exact approach. However, extant knowledge about how results of approximate measurement invariance tests compare to the results of the exact measurement invariance test is missing. We address this gap by comparing the results of exact and approximate cross-country measurement invariance tests of a revised scale to measure human values. Several studies that measured basic human values with the Portrait Values Questionnaire (PVQ) reported problems of measurement noninvariance (especially scalar noninvariance) across countries. Recently Schwartz et al. proposed a refined value theory and an instrument (PVQ-5X) to measure 19 more narrowly defined values. Cieciuch et al. tested its measurement invariance properties across eight countries and established exact scalar measurement invariance for 10 of the 19 values. The current study applied the approximate measurement invariance procedure on the same data and established approximate scalar measurement invariance even for all 19 values. Thus, the first conclusion is that the approximate approach provides more encouraging results for the usefulness of the scale for cross-cultural research, although this finding needs to be generalized and validated in future research using population data. The second conclusion is that the approximate measurement invariance is more likely than the exact approach to establish measurement invariance, although further simulation studies are needed to determine more precise recommendations about how large the permissible variance of the priors may be.

  7. Cross-Country Differences in the Additive Effects of Socioeconomics, Health Behaviors and Medical Comorbidities on Disability among Older Adults with Heart Disease

    PubMed Central

    Assari, Shervin

    2015-01-01

    Abstract Background: Patients with heart disease experience limited activities of daily living (ADL). This is a cross-country comparison of the additive effects of Socioeconomics, health behaviors, and the number of medical comorbidities on disability among patients with heart disease. Methods: The current study used a cross-sectional design. Data came from the Research on Early Life and Aging Trends and Effects (RELATE). The current analysis utilized data on elderly individuals (age ≥60 y) from 13 countries. The outcome was any ADL limitation (i.e. bathing, dressing, using toilet, transferring, lifting heavy things, shopping, and eating meals). Socioeconomics (i.e. age, gender, education, and income), health behaviors (i.e. exercise, smoking, and drinking), and number of chronic medical conditions (i.e. hypertension, respiratory, arthritis, stroke, and diabetes) were entered into country-specific logistic regressions, considering at least one limitation in ADL as the main outcome. Results: Number of comorbid medical conditions and age were positively associated with disability in 85% of the countries. Physical activity and drinking were linked to disability in 54%and 31% of countries, respectively. Higher education and income were associated with lower disability in 31% and 23% of the countries, respectively. Female gender was associated with higher disability only in 15% of the countries. Smoking was not associated with disability, while the effects of socioeconomics, drinking, exercise, and medical comorbidities were controlled. Conclusion: Determinants of disability depend on the country; accordingly, locally designed health promotion interventions may be superior to the universal interventions for patients with heart disease. Medical comorbidities, however, should be universally diagnosed and treated. PMID:26157460

  8. Airway hyperresponsiveness to methacholine, adenosine 5-monophosphate, mannitol, eucapnic voluntary hyperpnoea and field exercise challenge in elite cross-country skiers

    PubMed Central

    Sue-Chu, Malcolm; Brannan, John D; Anderson, Sandra D; Chew, Nora; Bjermer, Leif

    2010-01-01

    Background Methacholine hyperresponsiveness is prevalent in elite athletes. Comparative studies have hitherto been limited to methacholine, eucapnic voluntary hyperpnoea and exercise. This study investigated airway responsiveness to these stimuli as well as to adenosine 5′-monophosphate (AMP) and mannitol, in 58 cross-country ski athletes. Methods Exhaled nitric oxide concentration (FENO), spirometry and bronchial challenge in random order with methacholine, AMP and mannitol were consecutively performed on three study days in the autumn. Specific IgE to eight aeroallergens and a self-completed questionnaire about respiratory symptoms, allergy and asthmatic medication were also performed on day 1. Eucapnic voluntary hyperventilation (EVH) and field exercise tests were randomly performed in 33 of the skiers on two study days in the following winter. Results Of 25 (43%) skiers with airway hyperresponsiveness (AHR), 23, five and three skiers were hyperresponsive to methacholine, AMP and mannitol, respectively. Methacholine hyperresponsiveness was more prevalent in subjects without asthma-like symptoms. The FENO was not significantly different in skiers with and without methacholine hyperresponsiveness. Four of 14 skiers with and four of 19 skiers without methacholine hyperresponsiveness were hyperresponsive to EVH or exercise challenge. AHR to any stimulus was present in 16 asymptomatic and nine symptomatic skiers. Asthma-like symptoms were not correlated with AHR to any stimulus. Conclusions Methacholine hyperresponsiveness is more common in asymptomatic skiers and is a poor predictor of hyperresponsiveness to mannitol and hyperpnoea. The low prevalence of hyperresponsiveness to indirect stimuli may suggest differences in the pathogenesis of methacholine hyperresponsiveness in elite skiers and non-athletes. PMID:20460257

  9. Impact of the initial classic section during a simulated cross-country skiing skiathlon on the cardiopulmonary responses during the subsequent period of skate skiing.

    PubMed

    Mourot, Laurent; Fabre, Nicolas; Andersson, Erik; Willis, Sarah J; Hébert-Losier, Kim; Holmberg, Hans-Christer

    2014-08-01

    The aim of this study was to assess potential changes in the performance and cardiorespiratory responses of elite cross-country skiers following transition from the classic (CL) to the skating (SK) technique during a simulated skiathlon. Eight elite male skiers performed two 6 km (2 × 3 km) roller-skiing time trials on a treadmill at racing speed: one starting with the classic and switching to the skating technique (CL1-SK2) and another employing the skating technique throughout (SK1-SK2), with continuous monitoring of gas exchanges, heart rates, and kinematics (video). The overall performance times in the CL1-SK2 (21:12 ± 1:24) and SK1-SK2 (20:48 ± 2:00) trials were similar, and during the second section of each performance times and overall cardiopulmonary responses were also comparable. However, in comparison with SK1-SK2, the CL1-SK2 trial involved significantly higher increases in minute ventilation (V̇E, 89.8 ± 26.8 vs. 106.8 ± 17.6 L·min(-1)) and oxygen uptake (V̇O2; 3.1 ± 0.8 vs 3.5 ± 0.5 L·min(-1)) 2 min after the transition as well as longer time constants for V̇E, V̇O2, and heart rate during the first 3 min after the transition. This higher cardiopulmonary exertion was associated with ∼3% faster cycle rates. In conclusion, overall performance during the 2 time trials did not differ. The similar performance times during the second sections were achieved with comparable mean cardiopulmonary responses. However, the observation that during the initial 3-min post-transition following classic skiing cardiopulmonary responses and cycle rates were slightly higher supports the conclusion that an initial section of classic skiing exerts an impact on performance during a subsequent section of skate skiing.

  10. Comparing results of an exact vs. an approximate (Bayesian) measurement invariance test: a cross-country illustration with a scale to measure 19 human values

    PubMed Central

    Cieciuch, Jan; Davidov, Eldad; Schmidt, Peter; Algesheimer, René; Schwartz, Shalom H.

    2014-01-01

    One of the most frequently used procedures for measurement invariance testing is the multigroup confirmatory factor analysis (MGCFA). Muthén and Asparouhov recently proposed a new approach to test for approximate rather than exact measurement invariance using Bayesian MGCFA. Approximate measurement invariance permits small differences between parameters otherwise constrained to be equal in the classical exact approach. However, extant knowledge about how results of approximate measurement invariance tests compare to the results of the exact measurement invariance test is missing. We address this gap by comparing the results of exact and approximate cross-country measurement invariance tests of a revised scale to measure human values. Several studies that measured basic human values with the Portrait Values Questionnaire (PVQ) reported problems of measurement noninvariance (especially scalar noninvariance) across countries. Recently Schwartz et al. proposed a refined value theory and an instrument (PVQ-5X) to measure 19 more narrowly defined values. Cieciuch et al. tested its measurement invariance properties across eight countries and established exact scalar measurement invariance for 10 of the 19 values. The current study applied the approximate measurement invariance procedure on the same data and established approximate scalar measurement invariance even for all 19 values. Thus, the first conclusion is that the approximate approach provides more encouraging results for the usefulness of the scale for cross-cultural research, although this finding needs to be generalized and validated in future research using population data. The second conclusion is that the approximate measurement invariance is more likely than the exact approach to establish measurement invariance, although further simulation studies are needed to determine more precise recommendations about how large the permissible variance of the priors may be. PMID:25249996

  11. Comparing results of an exact vs. an approximate (Bayesian) measurement invariance test: a cross-country illustration with a scale to measure 19 human values.

    PubMed

    Cieciuch, Jan; Davidov, Eldad; Schmidt, Peter; Algesheimer, René; Schwartz, Shalom H

    2014-01-01

    One of the most frequently used procedures for measurement invariance testing is the multigroup confirmatory factor analysis (MGCFA). Muthén and Asparouhov recently proposed a new approach to test for approximate rather than exact measurement invariance using Bayesian MGCFA. Approximate measurement invariance permits small differences between parameters otherwise constrained to be equal in the classical exact approach. However, extant knowledge about how results of approximate measurement invariance tests compare to the results of the exact measurement invariance test is missing. We address this gap by comparing the results of exact and approximate cross-country measurement invariance tests of a revised scale to measure human values. Several studies that measured basic human values with the Portrait Values Questionnaire (PVQ) reported problems of measurement noninvariance (especially scalar noninvariance) across countries. Recently Schwartz et al. proposed a refined value theory and an instrument (PVQ-5X) to measure 19 more narrowly defined values. Cieciuch et al. tested its measurement invariance properties across eight countries and established exact scalar measurement invariance for 10 of the 19 values. The current study applied the approximate measurement invariance procedure on the same data and established approximate scalar measurement invariance even for all 19 values. Thus, the first conclusion is that the approximate approach provides more encouraging results for the usefulness of the scale for cross-cultural research, although this finding needs to be generalized and validated in future research using population data. The second conclusion is that the approximate measurement invariance is more likely than the exact approach to establish measurement invariance, although further simulation studies are needed to determine more precise recommendations about how large the permissible variance of the priors may be. PMID:25249996

  12. Development and Application of a Next Generation Air Sensor Network for the Hong Kong Marathon 2015 Air Quality Monitoring.

    PubMed

    Sun, Li; Wong, Ka Chun; Wei, Peng; Ye, Sheng; Huang, Hao; Yang, Fenhuan; Westerdahl, Dane; Louie, Peter K K; Luk, Connie W Y; Ning, Zhi

    2016-01-01

    This study presents the development and evaluation of a next generation air monitoring system with both laboratory and field tests. A multi-parameter algorithm was used to correct for the impact of environmental conditions on the electrochemical sensors for carbon monoxide (CO) and nitrogen dioxide (NO2) pollutants. The field evaluation in an urban roadside environment in comparison to designated monitors showed good agreement with measurement error within 5% of the pollutant concentrations. Multiple sets of the developed system were then deployed in the Hong Kong Marathon 2015 forming a sensor-based network along the marathon route. Real-time air pollution concentration data were wirelessly transmitted and the Air Quality Health Index (AQHI) for the Green Marathon was calculated, which were broadcast to the public on an hourly basis. The route-specific sensor network showed somewhat different pollutant patterns than routine air monitoring, indicating the immediate impact of traffic control during the marathon on the roadside air quality. The study is one of the first applications of a next generation sensor network in international sport events, and it demonstrated the usefulness of the emerging sensor-based air monitoring technology in rapid network deployment to supplement existing air monitoring.

  13. Expanding What It Means to Make Evidence-Based Claims: Online Comments and the Boston Marathon Bombings

    ERIC Educational Resources Information Center

    Chandler-Olcott, Kelly

    2014-01-01

    This article argues that exploration of media coverage of a story like the Boston Marathon bombings, including online comments posted by readers, can support youth in reflecting on and thinking critically about a tragedy while offering opportunities for literacy pedagogy consistent with the goals of the Common Core State Standards for English…

  14. "We Are Not Terrorists," but More Likely Transnationals: Reframing Understandings about Immigrants in Light of the Boston Marathon Bombings

    ERIC Educational Resources Information Center

    Kasun, G. Sue

    2013-01-01

    The Boston Marathon bombings in April 2013 created a new kind of discomfort in the United States about "self-radicalized" terrorists, particularly related to Muslim immigrants. The two suspected bombers, brothers with Chechen backgrounds, had attended U.S. public schools. News media portrayed the brothers as "immigrants" and…

  15. Branched-chain amino acid supplementation during a 100-km ultra-marathon--a randomized controlled trial.

    PubMed

    Knechtle, Beat; Mrazek, Claudia; Wirth, Andrea; Knechtle, Patrizia; Rüst, Christoph Alexander; Senn, Oliver; Rosemann, Thomas; Imoberdorf, Reinhard; Ballmer, Peter

    2012-01-01

    Ultra-marathon running is supposed to increase the parameters of skeletal muscle damage and impair renal function. The purpose of this study was to investigate the effect of branched-chain amino acid supplementation on skeletal muscle damage and renal function during a 100-km ultra-marathon. Twenty-eight athletes were randomly divided into two groups, one group using branched-chain amino acid supplementation (BCAA) and a control group (CON). The athletes in the BCAA group were supplemented with a total of 50 g of an amino acid concentrate including 20 g of BCAA. The intake of energy, antioxidants and parameters of both skeletal muscle damage and renal function were determined. Race time was not different between BCAA and CON when controlled for the personal best time in a 100-km ultra-marathon. Neither the intake of energy and antioxidants nor the parameters of skeletal muscle damage and renal function were different between BCAA and CON. We concluded that BCAA-supplementation before and during a 100-km ultra-marathon had no effect on performance, skeletal muscle damage or renal function. PMID:23007065

  16. Branched-chain amino acid supplementation during a 100-km ultra-marathon--a randomized controlled trial.

    PubMed

    Knechtle, Beat; Mrazek, Claudia; Wirth, Andrea; Knechtle, Patrizia; Rüst, Christoph Alexander; Senn, Oliver; Rosemann, Thomas; Imoberdorf, Reinhard; Ballmer, Peter

    2012-01-01

    Ultra-marathon running is supposed to increase the parameters of skeletal muscle damage and impair renal function. The purpose of this study was to investigate the effect of branched-chain amino acid supplementation on skeletal muscle damage and renal function during a 100-km ultra-marathon. Twenty-eight athletes were randomly divided into two groups, one group using branched-chain amino acid supplementation (BCAA) and a control group (CON). The athletes in the BCAA group were supplemented with a total of 50 g of an amino acid concentrate including 20 g of BCAA. The intake of energy, antioxidants and parameters of both skeletal muscle damage and renal function were determined. Race time was not different between BCAA and CON when controlled for the personal best time in a 100-km ultra-marathon. Neither the intake of energy and antioxidants nor the parameters of skeletal muscle damage and renal function were different between BCAA and CON. We concluded that BCAA-supplementation before and during a 100-km ultra-marathon had no effect on performance, skeletal muscle damage or renal function.

  17. Development and Application of a Next Generation Air Sensor Network for the Hong Kong Marathon 2015 Air Quality Monitoring.

    PubMed

    Sun, Li; Wong, Ka Chun; Wei, Peng; Ye, Sheng; Huang, Hao; Yang, Fenhuan; Westerdahl, Dane; Louie, Peter K K; Luk, Connie W Y; Ning, Zhi

    2016-01-01

    This study presents the development and evaluation of a next generation air monitoring system with both laboratory and field tests. A multi-parameter algorithm was used to correct for the impact of environmental conditions on the electrochemical sensors for carbon monoxide (CO) and nitrogen dioxide (NO2) pollutants. The field evaluation in an urban roadside environment in comparison to designated monitors showed good agreement with measurement error within 5% of the pollutant concentrations. Multiple sets of the developed system were then deployed in the Hong Kong Marathon 2015 forming a sensor-based network along the marathon route. Real-time air pollution concentration data were wirelessly transmitted and the Air Quality Health Index (AQHI) for the Green Marathon was calculated, which were broadcast to the public on an hourly basis. The route-specific sensor network showed somewhat different pollutant patterns than routine air monitoring, indicating the immediate impact of traffic control during the marathon on the roadside air quality. The study is one of the first applications of a next generation sensor network in international sport events, and it demonstrated the usefulness of the emerging sensor-based air monitoring technology in rapid network deployment to supplement existing air monitoring. PMID:26861336

  18. Development and Application of a Next Generation Air Sensor Network for the Hong Kong Marathon 2015 Air Quality Monitoring

    PubMed Central

    Sun, Li; Wong, Ka Chun; Wei, Peng; Ye, Sheng; Huang, Hao; Yang, Fenhuan; Westerdahl, Dane; Louie, Peter K.K.; Luk, Connie W.Y.; Ning, Zhi

    2016-01-01

    This study presents the development and evaluation of a next generation air monitoring system with both laboratory and field tests. A multi-parameter algorithm was used to correct for the impact of environmental conditions on the electrochemical sensors for carbon monoxide (CO) and nitrogen dioxide (NO2) pollutants. The field evaluation in an urban roadside environment in comparison to designated monitors showed good agreement with measurement error within 5% of the pollutant concentrations. Multiple sets of the developed system were then deployed in the Hong Kong Marathon 2015 forming a sensor-based network along the marathon route. Real-time air pollution concentration data were wirelessly transmitted and the Air Quality Health Index (AQHI) for the Green Marathon was calculated, which were broadcast to the public on an hourly basis. The route-specific sensor network showed somewhat different pollutant patterns than routine air monitoring, indicating the immediate impact of traffic control during the marathon on the roadside air quality. The study is one of the first applications of a next generation sensor network in international sport events, and it demonstrated the usefulness of the emerging sensor-based air monitoring technology in rapid network deployment to supplement existing air monitoring. PMID:26861336

  19. Cumulative exposure to prior collective trauma and acute stress responses to the Boston marathon bombings.

    PubMed

    Garfin, Dana Rose; Holman, E Alison; Silver, Roxane Cohen

    2015-06-01

    The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metropolitan Boston (n = 846) and New York City (n = 941) completed Internet-based surveys shortly after the Boston Marathon bombings. Cumulative direct exposure and indirect exposure to prior community trauma and acute stress symptoms were assessed. Acute stress levels did not differ between Boston and New York metropolitan residents. Cumulative direct and indirect, live-media-based exposure to 9/11, Superstorm Sandy, and the Sandy Hook shooting were positively associated with acute stress responses in the covariate-adjusted model. People who experience multiple community-based traumas may be sensitized to the negative impact of subsequent events, especially in communities previously exposed to similar disasters. PMID:25896419

  20. Pacing, packing and sex-based differences in Olympic and IAAF World Championship marathons.

    PubMed

    Hanley, Brian

    2016-09-01

    The aim of this study was to describe pacing profiles and packing behaviours of athletes in Olympic and World Championship marathons. Finishing and split times were collated for 673 men and 549 women across nine competitions. The mean speeds for each intermediate 5 km and end 2.2 km segments were calculated. Medallists of both sexes maintained even-paced running from 10 km onwards whereas slower finishers dropped off the lead pack at approximately half-distance. Athletes who ran with the same opponents throughout slowed the least in the second half (P < 0.001, men: ES ≥ 1.19; women: ES ≥ 1.06), whereas other strategies such as moving between packs or running alone were less successful. Overall, women slowed less (P < 0.001, ES = 0.44) and were more likely to run a negative split (P < 0.001), and their more conservative start meant fewer women dropped out (P < 0.001). This also meant that women medallists sped up in the final 2.2 km, which might have decided the medal positions. Marathon runners are advised to identify rivals with similar abilities and ambitions to run alongside provided they start conservatively. Coaches should note important sex-based differences in tactics adopted and design training programmes accordingly. PMID:26736042

  1. Persistent effects of a marathon run on the pituitary-testicular axis.

    PubMed

    Tanaka, H; Cléroux, J; de Champlain, J; Ducharme, J R; Collu, R

    1986-04-01

    Plasma levels of testosterone (T), LH, FSH, prolactin (PRL), cortisol (F), dehydroepiandrosterone sulfate (DHAS), noradrenaline (NA), NA sulfate (NAS), adrenaline (A) and A sulfate (AS) were measured in 7 adult males before and immediately after a marathon run as well as every morning for 5 days after the run. While plasma T levels fell significantly on the first and the second postmarathon day, those of LH rose significantly during the first 3 postrun days. Plasma PRL and F values increased significantly only at the end of the marathon. Plasma levels of NA and NAS rose significantly at the end of the run and again on days 2 and 5 postmarathon, respectively. A similar pattern was observed for A and AS except for the second peak of free A. These results show that a strenuous physical exercise leads to a persistent relative insensitivity to LH of the testicular T biosynthetic machinery, while the feedback mechanisms operating at the hypothalamic-pituitary level are normal. Furthermore, they suggest that catecholamines may be responsible for the prolonged inhibitory effect of stress on T biosynthesis.

  2. The impact of a 24-h ultra-marathon on salivary antimicrobial protein responses.

    PubMed

    Gill, S K; Teixeira, A M; Rosado, F; Hankey, J; Wright, A; Marczak, S; Murray, A; Costa, R J S

    2014-10-01

    Depressed oral respiratory mucosal immunity and increased incidence of upper respiratory symptoms are commonly reported after bouts of prolonged exercise. The current study observed the impact of a 24-h continuous overnight ultra-marathon competition (distance range: 122-208 km; ambient temperature range: 0-20 °C) on salivary antimicrobial protein responses and incidence of upper respiratory symptoms. Body mass, unstimulated saliva and venous blood samples were taken from ultra-endurance runners (n=25) and controls (n=17), before and immediately after competition. Upper respiratory symptoms were assessed during and until 4-weeks after event completion. Samples were analyzed for salivary IgA, lysozyme, α-amylase and cortisol in addition to plasma osmolality. Decreased saliva flow rate (p<0.001), salivary IgA (p<0.001) and lysozyme (p=0.015) secretion rates, and increased salivary α-amylase secretion rate (p<0.001) and cortisol responses (p<0.001) were observed post-competition in runners, with no changes being observed in controls. No incidences of upper respiratory symptoms were reported by participants. A 24-h continuous overnight ultra-marathon resulted in the depression of some salivary antimicrobial protein responses, but no incidences of upper respiratory symptoms were evident during or following competition. Salivary antimicrobial protein synergism, effective management of non-infectious episodes, maintaining euhydration, and (or) favourable environmental influences could have accounted for the low prevalence of upper respiratory symptoms. PMID:24886918

  3. Impact of different running distances on muscle and lymphocyte DNA damage in amateur marathon runners.

    PubMed

    Ryu, Jae Hoon; Paik, Il Young; Woo, Jin Hee; Shin, Ki Ok; Cho, Su Youn; Roh, Hee Tae

    2016-01-01

    [Purpose] The aim of this study was to investigate the impact of different marathon running distances (10 km, 21 km, and 42.195 km) on muscle and lymphocyte DNA damage in amateur marathon runners. [Subjects and Methods] Thirty male amateur runners were randomly assigned to 10 km, 21 km, and 42 km groups, with 10 subjects in each group. Blood samples were collected before and after the races and on the 3rd day of recovery to examine levels of muscle damage (creatine kinase and lactate dehydrogenase) and lymphocyte DNA damage (DNA in the tail, tail length, and tail moment). [Results] Serum creatine kinase, serum lactate dehydrogenase, and tail moment were significantly higher after the races compared with before the races in all groups. In addition, the 42 km group showed significantly higher levels of creatine kinase, lactate dehydrogenase, and tail moment than the 10 km and 21 km groups after the races. [Conclusion] Strenuous endurance exercise can cause muscle and lymphocyte DNA damage, and the extent of such damage can increase as running distance increases. PMID:27065529

  4. Influence of tart cherry juice on indices of recovery following marathon running.

    PubMed

    Howatson, G; McHugh, M P; Hill, J A; Brouner, J; Jewell, A P; van Someren, K A; Shave, R E; Howatson, S A

    2010-12-01

    This investigation determined the efficacy of a tart cherry juice in aiding recovery and reducing muscle damage, inflammation and oxidative stress. Twenty recreational Marathon runners assigned to either consumed cherry juice or placebo for 5 days before, the day of and for 48 h following a Marathon run. Markers of muscle damage (creatine kinase, lactate dehydrogenase, muscle soreness and isometric strength), inflammation [interleukin-6 (IL-6), C-reactive protein (CRP) and uric acid], total antioxidant status (TAS) and oxidative stress [thiobarbituric acid reactive species (TBARS) and protein carbonyls] were examined before and following the race. Isometric strength recovered significantly faster (P=0.024) in the cherry juice group. No other damage indices were significantly different. Inflammation was reduced in the cherry juice group (IL-6, P<0.001; CRP, P<0.01; uric acid, P<0.05). TAS was ~10% greater in the cherry juice than the placebo group for all post-supplementation measures (P<0.05). Protein carbonyls was not different; however, TBARS was lower in the cherry juice than the placebo at 48 h (P<0.05). The cherry juice appears to provide a viable means to aid recovery following strenuous exercise by increasing total antioxidative capacity, reducing inflammation, lipid peroxidation and so aiding in the recovery of muscle function.

  5. Effects of warming temperatures on winning times in the Boston marathon.

    PubMed

    Miller-Rushing, Abraham J; Primack, Richard B; Phillips, Nathan; Kaufmann, Robert K

    2012-01-01

    It is not known whether global warming will affect winning times in endurance events, and counterbalance improvements in race performances that have occurred over the past century. We examined a time series (1933-2004) from the Boston Marathon to test for an effect of warming on winning times by men and women. We found that warmer temperatures and headwinds on the day of the race slow winning times. However, 1.6°C warming in annual temperatures in Boston between 1933 and 2004 did not consistently slow winning times because of high variability in temperatures on race day. Starting times for the race changed to earlier in the day beginning in 2006, making it difficult to anticipate effects of future warming on winning times. However, our models indicate that if race starting times had not changed and average race day temperatures had warmed by 0.058°C/yr, a high-end estimate, we would have had a 95% chance of detecting a consistent slowing of winning marathon times by 2100. If average race day temperatures had warmed by 0.028°C/yr, a mid-range estimate, we would have had a 64% chance of detecting a consistent slowing of winning times by 2100.

  6. Impact of different running distances on muscle and lymphocyte DNA damage in amateur marathon runners

    PubMed Central

    Ryu, Jae Hoon; Paik, Il Young; Woo, Jin Hee; Shin, Ki Ok; Cho, Su Youn; Roh, Hee Tae

    2016-01-01

    [Purpose] The aim of this study was to investigate the impact of different marathon running distances (10 km, 21 km, and 42.195 km) on muscle and lymphocyte DNA damage in amateur marathon runners. [Subjects and Methods] Thirty male amateur runners were randomly assigned to 10 km, 21 km, and 42 km groups, with 10 subjects in each group. Blood samples were collected before and after the races and on the 3rd day of recovery to examine levels of muscle damage (creatine kinase and lactate dehydrogenase) and lymphocyte DNA damage (DNA in the tail, tail length, and tail moment). [Results] Serum creatine kinase, serum lactate dehydrogenase, and tail moment were significantly higher after the races compared with before the races in all groups. In addition, the 42 km group showed significantly higher levels of creatine kinase, lactate dehydrogenase, and tail moment than the 10 km and 21 km groups after the races. [Conclusion] Strenuous endurance exercise can cause muscle and lymphocyte DNA damage, and the extent of such damage can increase as running distance increases. PMID:27065529

  7. ENDOCRINE RESPONSE TO AN ULTRA-MARATHON IN PRE- AND POST-MENOPAUSAL WOMEN

    PubMed Central

    Verzosa, M.L.S.

    2014-01-01

    Ultra-endurance competitions are becoming increasingly popular but there is limited research on female participants. The purpose of this study was to examine changes in estrogen and the IGF-I system in women after an ultra-marathon. Six pairs of pre- and post- menopausal women were matched for race finish times;mean finish time was 20 hours. Blood samples were drawn 24 hours before the race, at the finish, and 24 hours into recovery. Samples were analysed for estradiol, total IGF-I, IGFBP-1, and intact IGFBP-3. There was a significant increase in estradiol following the race in both groups (P < 0.05). Total IGF-I decreased after the race (P < 0.01) and remained lower in recovery. IGFBP-1 increased after the race (P < 0.001) but returned to pre-race levels after 24 hours, while intact IGFBP-3 was significantly lower post-race and in recovery (P < 0.001). Postmenopausal women had significantly lower estradiol at baseline, but there were no other group differences. These results demonstrate that among recreational female runners, an ultra-marathon is associated with IGF system changes that are consistent with an energy-deficient, catabolic state. Further research is needed to confirm the effect of these endocrine changes on health and performance. PMID:24899777

  8. Turning laboratory findings into therapy: a marathon goal that has to be reached

    PubMed Central

    Kotlan, Beatrix; Stroncek, David F.; Marincola, Francesco M.

    2012-01-01

    The mission of translational research involves difficult tasks to be accomplished for its ultimate goal, i.e. the introduction of novel, effective therapeutic strategies in the clinic to diminish human suffering and cure life-threatening diseases. Translational research (also referred to as translational medicine) facilitates the translation of investment in biomedical research into successful medical treatment. This includes the transfer of diagnostic and therapeutic advances by proving their efficacy in large evidence-based trials. Through the study of humans novel insights about disease are brought back to the laboratory to identify new, observation-based strategies. This “two-way road” (“bench to bedside and bedside to bench”) process includes formulating guidelines for drug development and principles for new therapeutic strategies; initiating clinical investigations that provide the biological basis for new therapies, and related clinical trials; defining therapeutic targets and clinical endpoints. It requires a systematic approach beginning with specimen sampling, patient data collection, laboratory investigations, data analysis, preclinical testing, clinical trials, treatment efficacy monitoring, and finally the evaluation of therapeutic result. The marathon well symbolizes the enormous efforts undertaken by clinicians, scientists, regulators, ethicists, patient advocates, drug developers, and others, coordinately attempting to overcome obstacles along this road toward the final “marathon goal in medicine”. PMID:19776705

  9. Detection of changes in the fractal scaling of heart rate and speed in a marathon race

    NASA Astrophysics Data System (ADS)

    Billat, Véronique L.; Mille-Hamard, Laurence; Meyer, Yves; Wesfreid, Eva

    2009-09-01

    The aim of this study was to detect changes in the fractal scaling behavior of heart rate and speed fluctuations when the average runner’s speed decreased with fatigue. Scaling analysis in heart rate (HR) and speed (S) dynamics of marathon runners was performed using the detrended fluctuation analysis (DFA) and the wavelet based structure function. We considered both: the short-range ( α1) and the long-range ( α2) scaling exponents for the DFA method separated by a change-point, n0=64=5.3 min (box length), the same for all the races. The variability of HR and S decreased in the second part of the marathon race, while the cardiac cost time series (i.e. the number of cardiac beats per meter) increased due to the decreasing speed behavior. The scaling exponents α1 and α2 of HR and α1 of S, increased during the race ( p<0.01) as did the HR wavelet scaling exponent ( τ). These findings provide evidence of the significant effect of fatigue induced by long exercise on the heart rate and speed variability.

  10. Study of weather and thermal comfort influence on sport performance: prognostic analysis applied to Rio de Janeiro's city marathon

    NASA Astrophysics Data System (ADS)

    Pallotta, M.; Herdies, D. L.; Gonçalves, L. G.

    2013-05-01

    There is nowadays a growing interest in the influence and impacts of weather and climate in human life. The weather conditions analysis shows the utility of this type of tool when applied in sports. These conditions act as a differential in strategy and training, especially for outdoor sports. This study had as aim objective develop weather forecast and thermal comfort evaluation targeted to sports, and hoped that the results can be used to the development of products and weather service in the Olympic Games 2016 in Rio de Janeiro City. The use of weather forecast applied to the sport showed to be efficient for the case of Rio de Janeiro City Marathon, especially due to the high spatial resolution. The WRF simulations for the three marathons studied showed good results for temperature, atmospheric pressure, and relative humidity. On the other hand, the forecast of the wind showed a pattern of overestimation of the real situation in all cases. It was concluded that the WRF model provides, in general, more representative simulations from 36 hours in advance, and with 18 hours of integration they were even better, describing efficiently the synoptic situation that would be found. A review of weather conditions and thermal comfort at specific points of the marathon route showed that there are significant differences between the stages of the marathon, which makes possible to plan the competition strategy under the thermal comfort. It was concluded that a relationship between a situation more thermally comfortable (uncomfortable) and the best (worst) time in Rio de Janeiro City Marathon

  11. Xpert(®) MTB/RIF under routine conditions in diagnosing pulmonary tuberculosis: a study in two hospitals in Pakistan.

    PubMed

    Shah, S K; Kumar, A M V; Dogar, O F; Khan, M A; Qadeer, E; Tahseen, S; Masood, F; Chandio, A K; Edginton, M E

    2013-03-21

    Xpert(®) MTB/RIF testing was offered to consecutive patients with presumptive tuberculosis (TB) attending two hospitals in Pakistan during April-May 2012, in addition to routine diagnostic protocol (smear microscopy, chest radiography and clinical judgement). We assessed the relative contribution of each tool in detecting pulmonary TB under routine conditions. Of 606 participants, 121 (20%) were detected as pulmonary TB: 46 (38%) by microscopy, 38 (31%) by Xpert alone and 37 (31%) on clinical and radiological grounds; 41 (65%) were detected by both Xpert and microscopy. One patient had rifampicin resistance. Although Xpert detected approximately twice as many TB cases as microscopy (n = 79, 65%), clinical judgement remained favoured by clinicians even when smear and Xpert were negative.

  12. A cross-country comparison of intensive care physicians’ beliefs about their transfusion behaviour: A qualitative study using the theoretical domains framework

    PubMed Central

    2012-01-01

    guideline is important for other professionals), and Motivation and goals (opposing beliefs about the importance of restrictive transfusion and compatibility with other goals), were also identified in this study. Similar to the UK study, the Theory of Planned Behaviour, Social Cognitive Theory, Operant Learning Theory, Action Planning, and Knowledge-Attitude-Behaviour model were identified as potentially relevant theories and models for further study. Personal project analysis was added to the Canadian study to explore the Motivation and goals domain in further detail. Conclusions A wide range of beliefs was identified by the Canadian ICU physicians as likely to influence their transfusion behaviour. We were able to demonstrate similar though not identical results in a cross-country comparison. Designing targeted behaviour-change interventions based on unique beliefs identified by physicians from two countries are more likely to encourage restrictive transfusion in ICU physicians in respective countries. This needs to be tested in future prospective clinical trials. PMID:22999460

  13. Comparison of Xpert MTB/RIF with Other Nucleic Acid Technologies for Diagnosing Pulmonary Tuberculosis in a High HIV Prevalence Setting: A Prospective Study

    PubMed Central

    Scott, Lesley E.; McCarthy, Kerrigan; Gous, Natasha; Nduna, Matilda; Van Rie, Annelies; Sanne, Ian; Venter, Willem F.; Duse, Adrian; Stevens, Wendy

    2011-01-01

    Background The Xpert MTB/RIF (Cepheid) non-laboratory-based molecular assay has potential to improve the diagnosis of tuberculosis (TB), especially in HIV-infected populations, through increased sensitivity, reduced turnaround time (2 h), and immediate identification of rifampicin (RIF) resistance. In a prospective clinical validation study we compared the performance of Xpert MTB/RIF, MTBDRplus (Hain Lifescience), LightCycler Mycobacterium Detection (LCTB) (Roche), with acid fast bacilli (AFB) smear microscopy and liquid culture on a single sputum specimen. Methods and Findings Consecutive adults with suspected TB attending a primary health care clinic in Johannesburg, South Africa, were prospectively enrolled and evaluated for TB according to the guidelines of the National TB Control Programme, including assessment for smear-negative TB by chest X-ray, clinical evaluation, and HIV testing. A single sputum sample underwent routine decontamination, AFB smear microscopy, liquid culture, and phenotypic drug susceptibility testing. Residual sample was batched for molecular testing. For the 311 participants, the HIV prevalence was 70% (n = 215), with 120 (38.5%) culture-positive TB cases. Compared to liquid culture, the sensitivities of all the test methodologies, determined with a limited and potentially underpowered sample size (n = 177), were 59% (47%–71%) for smear microscopy, 76% (64%–85%) for MTBDRplus, 76% (64%–85%) for LCTB, and 86% (76%–93%) for Xpert MTB/RIF, with specificities all >97%. Among HIV+ individuals, the sensitivity of the Xpert MTB/RIF test was 84% (69%–93%), while the other molecular tests had sensitivities reduced by 6%. TB detection among smear-negative, culture-positive samples was 28% (5/18) for MTBDRplus, 22% (4/18) for LCTB, and 61% (11/18) for Xpert MTB/RIF. A few (n = 5) RIF-resistant cases were detected using the phenotypic drug susceptibility testing methodology. Xpert MTB/RIF detected four of these five cases

  14. Localized and Areally Extensive Alterations in Marathon Valley, Endeavour Crater Rim, Mars

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Gellert, Ralf; Van Bommel, Scott; Arvidson, Raymond E.; Clark, Benton C.; Cohen, Barbara A.; Farrand, William H.; Ming, Douglas W.; Schroeder, Christian; Yen, Albert S.; Jolliff, Bradley L.

    2016-01-01

    Mars Exploration Rover Opportunity is exploring the rim of 22 km diameter, Noachian-aged Endeavour crater. Marathon Valley cuts through the central region of the western rim providing a window into the local lower rim stratigraphic record. Spectra from the Compact Reconnaissance Imaging Spectrometer for Mars show evidence for the occurrence of Fe-Mg smectite in this valley, indicating areally extensive and distinct lithologic units and/or styles of aqueous alteration. The Alpha Particle X-ray Spectrometer has determined the compositions of 59 outcrop targets on untreated, brushed and abraded surfaces. Rocks in the Marathon Valley region are soft breccias composed of mm- to cm-sized darker clasts set in a lighter-toned, finegrained matrix. They are basaltic in non-volatile-element composition and compositionally similar to breccias investigated elsewhere on the rim. Alteration styles recorded in the rocks include: (1) Enrichments in Si, Al, Ti and Cr in more reddish-colored rock, consistent with leaching of more soluble cations and/or precipitation of Si +/- Al, Ti, Cr from fluids. Coprecipitation of Ge-rich phases with Si occurred in the western area only; high water:rock is indicated. Pancam multispectral observations indicate higher nanophase ferric oxide contents, but the rocks have lower Fe contents. The highly localized nature of the red zones indicate they cannot be the source of the widespread smectite signature observed from orbit. (2) Outcrops separated by approximately 65 m show common compositional changes between brushed and abraded (approximately 1 mm deep) targets: increases in S and Mg; decreases in Al, Cl and Ca. These changes are likely due to relatively recent, surface-related alteration of valley rocks and formation of surface coatings under low water:rock. (3) One target, from the center of a region of strong CRISM smectite signature, shows modest differences in composition (higher Si, K; lower Mn) compared to most Marathon Valley rocks, while

  15. CFTR genotype-related body water and electrolyte balance during a marathon.

    PubMed

    Del Coso, J; Lara, B; Salinero, J J; Areces, F; Ruiz-Vicente, D; Gallo-Salazar, C; Abián-Vicén, J; Cacabelos, R

    2016-09-01

    The aim of this investigation was to determine the influence of CFTR genotype on body water and electrolyte balance during a marathon. Fifty-one experienced runners completed a marathon race. Before and after the race, body mass and a sample of venous blood were obtained. During the race, sweat samples were collected using sweat patches, and fluid and electrolyte intake were obtained using self-reported questionnaires. Thirty-eight participants (74.5% of the total) were 7T/7T homozygotes, 11 (21.6%) were 7T/9T heterozygotes, and one participant presented the rare genotype 5T/7T. Another participant with 9T/9T presented the mutation p.L206W. Participants with 7T/7T showed higher sweat sodium concentrations (42.2 ± 21.6 mmol/L) than 7T/9T (29.0 ± 24.7 mmol/L; P = 0.04). The runner with the 5T/7T genotype (10.2 mmol/L) and the participant with the p.L206W mutation (20.5 mmol/L) exhibited low-range sweat sodium concentrations. However, post-race serum sodium concentration was similar in 7T/7T and 7T/9T (142.1 ± 1.3 and 142.4 ± 1.6 mmol/L, respectively; P = 0.27) and did not show abnormalities in participants with the 5T/7T genotype (140.0 mmol/L) and the p.L206W mutation (143.0 mmol/L). Runners with the CFTR-7T/7T genotype exhibited increased sweat sodium concentrations during a marathon. However, this phenotype was not related with increased likelihood of suffering body water and electrolyte imbalances during real competitions. PMID:26282188

  16. Increase in finishers and improvement of performance of masters runners in the Marathon des Sables

    PubMed Central

    Jampen, Saskia Carolin; Knechtle, Beat; Rüst, Christoph Alexander; Lepers, Romuald; Rosemann, Thomas

    2013-01-01

    Aim The aim of the study was to examine finisher and performance trends of ultrarunners in the Marathon des Sables, the world’s largest multistage ultramarathon. Methods The age and running speed was analyzed for 6945 finishes of 909 women and 6036 men between 2003 and 2012 at the Marathon des Sables covering about 240 km in the Moroccan desert. Results The number of finishes increased significantly for both women and men from 2003–2012. The annual number of finishes increased in age groups: 30–34 years (r2 = 0.50; P = 0.021), 45–49 years (r2 = 0.81; P = 0.0004), and 50–54 years (r2 = 0.46; P = 0.029) for women and in all age groups older than 35 years for men (35–39 years: r2 = 0.64, P = 0.0054; 40–44 years: r2 = 0.67, P = 0.0036; 45–49 years: r2 = 0.77, P = 0.0007; 50–54 years: r2 = 0.72, P = 0.0018; 55–59 years: r2 = 0.42, P = 0.041; and 60–64 years: r2 = 0.67, P = 0.0038). The fastest running speed was achieved by runners in the age group of 35–39 years for both sexes. The mean age of overall finishers was 41.0 ± 9.1 years for women and 41.3 ± 9.5 years for men. For men, running speed improved for athletes in the age group of 35–39 years (r2 = 0.44; P = 0.036) and of 40–44 years (r2 = 0.51; P = 0.019), while it decreased for athletes in the age group of 30–34 years (r2 = 0.66, P = 0.0039). For women, running speed remained stable during the study period for athletes in all age groups. Conclusion These data suggest that the number of finishers of masters runners older than 40 years increased for both sexes at the Marathon des Sables, as has been previously observed for single-stage ultramarathons. In contrast to women, men aged 35 to 44 years improved running speed during the study period. Future studies are needed to investigate the reasons for the growing numbers of masters athletes in endurance sports and their improvement in performance. PMID:23776392

  17. The Protective Effect of the Mycobacterium bovis BCG Vaccine Is Increased by Coadministration with the Mycobacterium tuberculosis 72-Kilodalton Fusion Polyprotein Mtb72F in M. tuberculosis-Infected Guinea Pigs

    PubMed Central

    Brandt, Lise; Skeiky, Yasir A. W.; Alderson, Mark R.; Lobet, Yves; Dalemans, Wilfried; Turner, Oliver C.; Basaraba, Randall J.; Izzo, Angelo A.; Lasco, Todd M.; Chapman, Philip L.; Reed, Steven G.; Orme, Ian M.

    2004-01-01

    A tuberculosis vaccine candidate consisting of a 72-kDa polyprotein or fusion protein based upon the Mtb32 and Mtb39 antigens of Mycobacterium tuberculosis and designated Mtb72F was tested for its protective capacity as a potential adjunct to the Mycobacterium bovis BCG vaccine in the mouse and guinea pig models of this disease. Formulation of recombinant Mtb72F (rMtb72F) in an AS02A adjuvant enhanced the Th1 response to BCG in mice but did not further reduce the bacterial load in the lungs after aerosol challenge infection. In the more stringent guinea pig disease model, rMtb72F delivered by coadministration with BCG vaccination significantly improved the survival of these animals compared to BCG alone, with some animals still alive and healthy in their appearance at >100 weeks post-aerosol challenge. A similar trend was observed with guinea pigs in which BCG vaccination was boosted by DNA vaccination, although this increase was not statistically significant due to excellent protection conferred by BCG alone. Histological examination of the lungs of test animals indicated that while BCG controls eventually died from overwhelming lung consolidation, the majority of guinea pigs receiving BCG mixed with rMtb72F or boosted twice with Mtb72F DNA had mostly clear lungs with minimal granulomatous lesions. Lesions were still prominent in guinea pigs receiving BCG and the Mtb72F DNA boost, but there was considerable evidence of lesion healing and airway remodeling and reestablishment. These data support the hypothesis that the coadministration or boosting of BCG vaccination with Mtb72F may limit the lung consolidation seen with BCG alone and may promote lesion resolution and healing. Collectively, these data suggest that enhancing BCG is a valid vaccination strategy for tuberculosis that is worthy of clinical evaluation. PMID:15501795

  18. Personal best times in an Olympic distance triathlon and in a marathon predict Ironman race time in recreational male triathletes

    PubMed Central

    Rüst, Christoph Alexander; Knechtle, Beat; Knechtle, Patrizia; Rosemann, Thomas; Lepers, Romuald

    2011-01-01

    Background The purpose of this study was to define predictor variables for recreational male Ironman triathletes, using age and basic measurements of anthropometry, training, and previous performance to establish an equation for the prediction of an Ironman race time for future recreational male Ironman triathletes. Methods Age and anthropometry, training, and previous experience variables were related to Ironman race time using bivariate and multivariate analysis. Results A total of 184 recreational male triathletes, of mean age 40.9 ± 8.4 years, height 1.80 ± 0.06 m, and weight 76.3 ± 8.4 kg completed the Ironman within 691 ± 83 minutes. They spent 13.9 ± 5.0 hours per week in training, covering 6.3 ± 3.1 km of swimming, 194.4 ± 76.6 km of cycling, and 45.0 ± 15.9 km of running. In total, 149 triathletes had completed at least one marathon, and 150 athletes had finished at least one Olympic distance triathlon. They had a personal best time of 130.4 ± 44.2 minutes in an Olympic distance triathlon and of 193.9 ± 31.9 minutes in marathon running. In total, 126 finishers had completed both an Olympic distance triathlon and a marathon. After multivariate analysis, both a personal best time in a marathon (P < 0.0001) and in an Olympic distance triathlon (P < 0.0001) were the best variables related to Ironman race time. Ironman race time (minutes) might be partially predicted by the following equation: (r2 = 0.65, standard error of estimate = 56.8) = 152.1 + 1.332 × (personal best time in a marathon, minutes) + 1.964 × (personal best time in an Olympic distance triathlon, minutes). Conclusion These results suggest that, in contrast with anthropometric and training characteristics, both the personal best time in an Olympic distance triathlon and in a marathon predict Ironman race time in recreational male Ironman triathletes. PMID:24198578

  19. Threat perception after the Boston Marathon bombings: The effects of personal relevance and conceptual framing.

    PubMed

    Wormwood, Jolie Baumann; Lynn, Spencer K; Feldman Barrett, Lisa; Quigley, Karen S

    2016-01-01

    We examined how the Boston Marathon bombings affected threat perception in the Boston community. In a threat perception task, participants attempted to "shoot" armed targets and avoid shooting unarmed targets. Participants viewing images of the bombings accompanied by affectively negative music and text (e.g., "Terror Strikes Boston") made more false alarms (i.e., more errors "shooting" unarmed targets) compared to participants viewing the same images accompanied by affectively positive music and text (e.g., "Boston Strong") and participants who did not view bombing images. This difference appears to be driven by decreased sensitivity (i.e., decreased ability to distinguish guns from non-guns) as opposed to a more liberal bias (i.e., favouring the "shoot" response). Additionally, the more strongly affected the participant was by the bombings, the more their sensitivity was reduced in the negatively framed condition, suggesting that this framing was particularly detrimental to the most vulnerable individuals in the affected community. PMID:25707419

  20. The role of salt and glucose replacement drinks in the marathon.

    PubMed

    Murray, Bob

    2007-01-01

    There is a large and growing body of scientific evidence that documents the benefits of ingesting salt and glucose (carbohydrates) during prolonged exercise. Those benefits include maintenance of cardiovascular function, enhanced carbohydrate oxidation, blunted decline in plasma sodium concentration and improved performance. The consumption of approximately 1g of carbohydrate per kilogram of bodyweight per hour appears sufficient to improve performance in prolonged exercise. Research also indicates that approximately 450mg of sodium per hour is the minimum amount required to maintain plasma volume and slow the decline in plasma sodium concentration that can accompany prolonged exercise in some runners. Adequate carbohydrate and electrolyte intake can be achieved by consuming a well formulated sports drink at regular intervals during exercise, in volumes designed to minimise dehydration. For marathon runners, this could range from approximately 400mL to >1.5L per hour, depending upon individual sweating rates.

  1. Plastic surgeons and the management of trauma: from the JFK assassination to the Boston Marathon bombing.

    PubMed

    Luce, Edward A; Hollier, Larry H; Lin, Samuel J

    2013-11-01

    The fiftieth anniversary of the death by assassination of President John Kennedy is an opportunity to pay homage to his memory and also reflect on the important role plastic surgeons have played in the management of trauma. That reflection included a hypothetical scenario, a discussion of the surgical treatment of Kennedy (if he survived) and Governor Connally. The scenario describes the management of cranioplasty in the presence of scalp soft-tissue contracture, reconstruction of the proximal trachea, reconstitution of the abdominal wall, and restoration of a combined radius and soft-tissue defect. The development of diagnostic and therapeutic advances over the past 50 years in the care of maxillofacial trauma is described, including the evolution of imaging, timing of surgery, and operative techniques. Finally, contemporary measures of triage in situations involving mass casualties, as in the Boston Marathon bombings, complete the dedication to President Kennedy.

  2. Threat perception after the Boston Marathon bombings: The effects of personal relevance and conceptual framing.

    PubMed

    Wormwood, Jolie Baumann; Lynn, Spencer K; Feldman Barrett, Lisa; Quigley, Karen S

    2016-01-01

    We examined how the Boston Marathon bombings affected threat perception in the Boston community. In a threat perception task, participants attempted to "shoot" armed targets and avoid shooting unarmed targets. Participants viewing images of the bombings accompanied by affectively negative music and text (e.g., "Terror Strikes Boston") made more false alarms (i.e., more errors "shooting" unarmed targets) compared to participants viewing the same images accompanied by affectively positive music and text (e.g., "Boston Strong") and participants who did not view bombing images. This difference appears to be driven by decreased sensitivity (i.e., decreased ability to distinguish guns from non-guns) as opposed to a more liberal bias (i.e., favouring the "shoot" response). Additionally, the more strongly affected the participant was by the bombings, the more their sensitivity was reduced in the negatively framed condition, suggesting that this framing was particularly detrimental to the most vulnerable individuals in the affected community.

  3. The effects of marathon swimming on serum leptin and plasma neuropeptide Y levels.

    PubMed

    Karamouzis, Ioannis; Karamouzis, Michael; Vrabas, Ioannis S; Christoulas, Kosmas; Kyriazis, Nikitas; Giannoulis, Eleftherios; Mandroukas, Konstantinos

    2002-02-01

    It seems likely that the neuropeptide Y (NPY)-leptin axis is involved in the regulation of energy expenditure in man. The purpose of this study was to observe the effect of a model of intense prolonged exercise-mediated energy expenditure (25 km swim race in 6.9-10.5 hours) on leptin and NPY concentrations in male long-distance swimmers. Sixteen long-distance swimmers (mean age 25, range 18-45 years) who took part in a 25 km sea swimming competition (Toroneos golf, Chalkidiki, Greece) participated in the study. Mean competition time was 8.5 hours (range 6.5-10.5). The participants were allowed food and beverage intake ad libitum before and throughout the 25 km race. Venous blood samples were taken prior and immediately after the race for the measurement of serum leptin and plasma NPY. Non-esterified free fatty acids (NEFFA) and glycerol levels were determined as indicators of adipose tissue lipids mobilization. Results showed that leptin levels after marathon swimming were significantly reduced (p<0.001) in all athletes. There was a statistically significant negative correlation (r=-0.812, p<0.01) between the values of leptin and glycerol just after the termination of swimming. Blood serum glycerol and free fatty acid levels were significantly increased (p<0.001) in all swimmers. Plasma NPY levels were also increased (p<0.01) in 81.2% of the swimmers. Linear regression analysis revealed a significant negative correlation between the values of leptin and NPY (r=-0.789, p<0.01). In conclusion, these data support our initial hypothesis that appropriate changes in leptin and NPY take place during marathon swimming to compensate for the negative energy balance produced due to this prolonged effort. This indicates the NPY-leptin axis involvement in the regulation of energy expenditure in man. PMID:11939485

  4. Monitoring the dynamic behaviors of the Bosporus Bridge by GPS during Eurasia Marathon

    NASA Astrophysics Data System (ADS)

    Erdoǧan, H.; Akpınar, B.; Gülal, E.; Ata, E.

    2007-08-01

    Engineering structures, like bridges, dams and towers are designed by considering temperature changes, earthquakes, wind, traffic and pedestrian loads. However, generally, it can not be estimated that these structures may be affected by special, complex and different loads. So it could not be known whether these loads are dangerous for the structure and what the response of the structures would be to these loads. Such a situation occurred on the Bosporus Bridge, which is one of the suspension bridges connecting the Asia and Europe continents, during the Eurasia Marathon on 2 October 2005, in which 75 000 pedestrians participated. Responses of the bridge to loads such as rhythmic running, pedestrian walking, vehicle passing during the marathon were observed by a real-time kinematic (RTK) Global Positioning System (GPS), with a 2.2-centimeter vertical accuracy. Observed responses were discussed in both time domain and frequency domain by using a time series analysis. High (0.1-1 Hz) and low frequencies (0.00036-0.01172 Hz) of observed bridge responses under 12 different loads which occur in different quantities, different types and different time intervals were calculated in the frequency domain. It was seen that the calculated high frequencies are similar, except for the frequencies of rhythmic running, which causes a continuously increasing vibration. Any negative response was not determined, because this rhythmic effect continued only for a short time. Also when the traffic load was effective, explicit changes in the bridge movements were determined. Finally, it was seen that bridge frequencies which were calculated from the observations and the finite element model were harmonious. But the 9th natural frequency value of the bridge under all loads, except rhythmic running could not be determined with observations.

  5. Magnetic behaviour of the MTbF{sub 6} fluoroterbates (M=Cd, Ca, Sr, ({alpha}/{beta})-Ba)

    SciTech Connect

    Josse, M.; El-Ghozzi, M.; Avignant, D.; Andre, G.; Bouree, F.; Isnard, O.

    2012-01-15

    Neutron powder diffraction has been performed on the MTbF{sub 6} fluorides (M=Cd, Ca, Sr, ({alpha}/{beta})-Ba). Four of these fluorides (Cd, Ca, Sr, {beta}-Ba) are built of a (pseudo-) tetragonal packing of [TbF{sub 6}]{sup 2-} chains and only differs by the chains relative orientations. Thus this series represents a valuable opportunity to evaluate the Tb{sup 4+}-Tb{sup 4+} magnetic interactions. All the compounds displayed antiferromagnetic order (T{sub N}=2.70 K (Cd), 2.15 K (Ca), 2.60 K (Sr), 2.10 K ({beta}-Ba)), except for the {alpha} form of BaTbF{sub 6}. The crystal structure of this latter fluoroterbate has also been investigated by means of high-resolution neutron powder diffraction. From Neutron Powder Diffraction data, CdTbF{sub 6} and {beta}-BaTbF{sub 6} magnetic structures were determined, together with the metamagnetic behaviour of {beta}-BaTbF{sub 6} as a function of an external magnetic field. A tentative phase diagram is then given for {beta}-BaTbF{sub 6}. Advantage was taken of the polymorphism of the BaTbF{sub 6} fluoroterbate to analyse, on the basis of topological parameters such as bond distances and angles, the magnetic behaviour of its {alpha} and {beta} forms. It was shown that superexchange interactions are present in {beta}-BaTbF{sub 6}, and that these interactions may also rule the magnetic behaviour of the other MTbF{sub 6} (M=Ca, Sr, Cd) tetravalent terbium fluorides. - Graphical abstract: Powder neutron diffraction revealed magnetic order in four of the five investigated fluoroterbates, while crystal chemical analyses of {alpha} and {beta} forms of BaTbF{sub 6} evidenced the existence of superexchange interactions. Highlights: Black-Right-Pointing-Pointer Five fluoroterbates are investigated by Powder Neutron Diffraction (PND). Black-Right-Pointing-Pointer Four of them are antiferromagnetically ordered at 1.4 K. Black-Right-Pointing-Pointer Magnetic structures of {beta}-BaTbF{sub 6} and CdTbF{sub 6} are determined. Black

  6. Structure of the Mtb CarD/RNAP β-lobes complex reveals the molecular basis of interaction, and presents a novel DNA binding domain for Mtb CarD

    PubMed Central

    Gulten, Gulcin; Sacchettini, James C.

    2013-01-01

    SUMMARY CarD from Mycobacterium tuberculosis (Mtb) is an essential protein thought to be involved in stringent response through downregulation of rRNA and ribosomal protein genes. CarD interacts with the β-subunit of RNAP and this interaction is vital for Mtb’s survival during the persistent infection state. We have determined the crystal structure of CarD in complex with the RNAP β-subunit β1 and β2 domains at 2.1 Å resolution. The structure reveals the molecular basis of CarD/RNAP interaction, providing a basis to further our understanding of RNAP regulation by CarD. The structural fold of the CarD N-terminal domain is conserved in RNAP interacting proteins such as TRCF-RID and CdnL, and displays similar interactions to the predicted homology model based on the TRCF/RNAP β1 structure. Interestingly, the structure of the C-terminal domain, which is required for complete CarD function in vivo, represents a novel DNA binding fold. PMID:24055315

  7. Evading the fate of Pheidippides: acute coronary thrombosis in a young marathon runner with minimal atherosclerosis but sickle cell trait.

    PubMed

    Murray, Scott W; Cooper, Robert M; Mills, Joseph D; Palmer, Nicholas D

    2015-08-01

    Marathon running transiently increases the risk of sudden cardiac death. Some previous studies have suggested that this is due to relatively advanced but asymptomatic atherosclerosis. Other theories suggest that potentiation of inflammation and the coagulation cascade, by extremes of exertion, is more important. We present a clinical case of a young, previously fit athlete who felt chest discomfort eight miles into a marathon but finished the race. Shortly after completion he felt very unwell and had chest pain. Ambulance electrocardiograms showed evidence of an evolving anterior myocardial infarction. Invasive assessment with coronary angiography and intravascular ultrasound was able to show the mechanism of thrombosis. Fissuring of a small rim of atherosclerosis potentiated a large pro-thrombotic response, the patient was also found to have sickle cell trait. Medical treatment with blood thinning drugs was able to restore normality to the vessel over a period of two weeks, without the need for angioplasty or stent implantation. PMID:26331117

  8. [Running helps--or how you escape depression without a psychiatrist and end up running a marathon!].

    PubMed

    Knechtle, B; Quarella, A

    2007-09-01

    We describe the case of a 27-year-old woman with adjustment disorder, disturbances of other feelings such as fear, depression, worries, anxiety and anger due to various burdens such as conflict with boyfriend and unclear job situation (ICD-10 f4323); furthermore, a status after intoxication with sleeping pills (ICD-10 X61) due to a difficult family situation. Regular endurance training helped the young woman to get over her serious life crisis and start a new life without psychiatrist and psychopharmaca. Thanks to progressively increasing running training, the patient was able to run a half-marathon in her first training year and aims for marathon and Powerman-Duathlon in the future. PMID:17894119

  9. Discordance between MTB/RIF and Real-Time Tuberculosis-Specific Polymerase Chain Reaction Assay in Bronchial Washing Specimen and Its Clinical Implications

    PubMed Central

    Jo, Yong Suk; Park, Ju-Hee; Lee, Jung Kyu; Heo, Eun Young; Chung, Hee Soon

    2016-01-01

    The prevalence and clinical implications of discordance between Xpert MTB/RIF assays and the AdvanSure TB/NTM real-time polymerase chain reaction (PCR) for bronchial washing specimens have not been studied in pulmonary TB (PTB) patients. The discordant proportion and its clinical impact were evaluated in 320 patients from the bronchoscopy registry whose bronchial washing specimens were tested simultaneously with Xpert MTB/RIF and the TB/NTM PCR assay for three years, and the accuracy of the assays, including the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were studied. The clinical risk factors for discordance and false positivity of assays were also studied. Among 130 patients who were clinically diagnosed with PTB, 64 patients showed positive acid-fast bacilli culture results, 56 patients showed positive results in molecular methods and clinician diagnosed PTB without results of microbiology in 10 patients. The sensitivity, specificity, PPV, and NPV were 80.0%, 98.95%, 98.1%, and 87.9%, respectively, for Xpert MTB/RIF and 81.5%, 92.6%, 88.3%, and 88.0%, respectively, for TB/NTM PCR. The discordant proportion was 16.9% and was higher in culture-negative PTB compared to culture-confirmed PTB (24.3% vs. 9.4%, p = 0.024). However, there were no significant differences in the clinical characteristics, regardless of the discordance. The diagnostic yield increased with an additional assay (7.7% for Xpert MTB/RIF and 9.2% for TB/NTM PCR). False positivity was less common in patients tested with Xpert MTB/RIF (1.05% vs. 7.37%, p = 0.0035). No host-related risk factor for false positivity was identified. The Xpert MTB/RIF and TB/NTM PCR assay in bronchial washing specimens can improve the diagnostic yields for PTB, although there were considerable discordant results without any patient-related risk factors. PMID:27760181

  10. Write-a-Thon: How To Conduct a Writing Marathon in Your Third-to-Fifth-Grade Class.

    ERIC Educational Resources Information Center

    Wilde, Susie

    This book takes the elementary school teacher through all the paces needed to conduct a 2-day writing marathon in the classroom. According to the book, working as a team and having the opportunity to write without interruption are the main goals of a "write-a-thon," but play is a key element to its success. The book explains step-by-step how to:…

  11. Influence of body mass loss and myoglobinuria on the development of muscle fatigue after a marathon in a warm environment.

    PubMed

    Del Coso, Juan; Salinero, Juan José; Abián-Vicen, Javier; González-Millán, Cristina; Garde, Sergio; Vega, Pablo; Pérez-González, Benito

    2013-03-01

    The aim of this study was to determine the changes in body mass and myoglobinuria concentration in recreational runners during a marathon in a warm environment, and the relation of these changes to muscle fatigue. We recruited 138 amateur runners (114 men and 24 women) for the study. Before the race, leg muscle power output was measured during a countermovement jump on a force platform, body weight was measured, and a urine sample was obtained. Within 3 min of race completion (28 °C; 46% relative humidity), the runners repeated the countermovement jump, body weight was measured again, and a second urine sample was obtained. Myoglobin concentration was determined in the urine samples. After the race, mean body mass reduction was 2.2% ± 1.2%. Fifty-five runners (40% of the total) reduced their body mass by less than 2%, and 10 runners (7.2%) reduced their body mass by more than 4%. Only 3 runners increased their body mass after the marathon. Mean leg muscle power reduction was 16% ± 10%. Twenty-four runners reduced their muscle power by over 30%. No myoglobin was detected in the prerace urine specimens, whereas postrace urinary myoglobin concentration increased to 3.5 ± 9.5 μg·mL(-1) (p < 0.05). Muscle power change after the marathon significantly correlated with postrace urine myoglobin concentration (r = -0.55; p < 0.001), but not with body mass change (r = -0.08; p = 0.35). After a marathon in a warm environment, interindividual variability in body mass change was high, but only 7% of the runners reduced their body mass by more than 4%. The correlation between myoglobinuria and muscle power change suggests that muscle fatigue is associated with muscle breakdown.

  12. Power law scaling behavior of physiological time series in marathon races using wavelet leaders and detrended fluctuation analysis

    NASA Astrophysics Data System (ADS)

    Wesfreid, Eva; Billat, Véronique

    2009-02-01

    Data power law scaling behavior is observed in many fields. Velocity of fully developed turbulent flow, telecommunication traffic in networks, financial time series are some examples among many others. The goal of the present contribution is to show the scaling behavior of physiological time series in marathon races using wavelet leaders and the Detrended Fluctuation Analysis. Marathon race is an exhausting exercise, it is referenced as being a model for studying the limits of human ambulatory abilities. We analyzed the athlete's heart rate and speed time series recorded simultaneously. We find that the heart cost time series, number of heart beats per meter, increases with the fatigue appearing during the marathon race, its tendency grows in the second half of the race for all athletes. For most physiological time series, we observed a concave behavior of the wavelet leaders scaling exponents which suggests a multifractal behavior. Otherwise, the Detrended Fluctuation Analysis shows short and long range time-scale power law exponents with the same break point for each physiological time series and each athlete. The short range time-scale exponent increases with fatigue in most physiological signals.

  13. It’s a Matter of Mind! Cognitive Functioning Predicts the Athletic Performance in Ultra-Marathon Runners

    PubMed Central

    Cona, Giorgia; Cavazzana, Annachiara; Paoli, Antonio; Marcolin, Giuseppe; Grainer, Alessandro; Bisiacchi, Patrizia Silvia

    2015-01-01

    The present study was aimed at exploring the influence of cognitive processes on performance in ultra-marathon runners, providing an overview of the cognitive aspects that characterize outstanding runners. Thirty runners were administered a battery of computerized tests right before their participation in an ultra-marathon. Then, they were split according to the race rank into two groups (i.e., faster runners and slower runners) and their cognitive performance was compared. Faster runners outperformed slower runners in trials requiring motor inhibition and were more effective at performing two tasks together, successfully suppressing the activation of the information for one of the tasks when was not relevant. Furthermore, slower runners took longer to remember to execute pre-defined actions associated with emotional stimuli when such stimuli were presented. These findings suggest that cognitive factors play a key role in running an ultra-marathon. Indeed, if compared with slower runners, faster runners seem to have a better inhibitory control, showing superior ability not only to inhibit motor response but also to suppress processing of irrelevant information. Their cognitive performance also appears to be less influenced by emotional stimuli. This research opens new directions towards understanding which kinds of cognitive and emotional factors can discriminate talented runners from less outstanding runners. PMID:26172546

  14. "Personal best times in an olympic distance triathlon and a marathon predict an ironman race time for recreational female triathletes".

    PubMed

    Rüst, Christoph Alexander; Knechtle, Beat; Wirth, Andrea; Knechtle, Patrizia; Ellenrieder, Birte; Rosemann, Thomas; Lepers, Romuald

    2012-06-30

    "The aim of this study was to investigate whether the characteristics of anthropometry, training or previous performance were related to an Ironman race time in recreational female Ironman triathletes. These characteristics were correlated to an Ironman race time for 53 recreational female triathletes in order to determine the predictor variables, and so be able to predict an Ironman race time for future novice triathletes. In the bi-variate analysis, no anthropometric characteristic was related to race time. The weekly cycling kilometers (r = -0.35) and hours (r = -0.32), as well as the personal best time in an Olympic distance triathlon (r = 0.49) and in a marathon (r = 0.74) were related to an Ironman race time (< 0.05). Stepwise multiple regressions showed that both the personal best time in an Olympic distance triathlon ( P = 0.0453) and in a marathon (P = 0.0030) were the best predictors for the Ironman race time (n = 28, r² = 0.53). The race time in an Ironman triathlon might be partially predicted by the following equation (r² = 0.53, n = 28): Race time (min) = 186.3 + 1.595 × (personal best time in an Olympic distance triathlon, min) + 1.318 × (personal best time in a marathon, min) for recreational female Ironman triathletes."

  15. Diagnosis and treatment of TB patients with rifampicin resistance detected using Xpert® MTB/RIF in Zimbabwe

    PubMed Central

    Ade, S.; Harries, A. D.; Ncube, R. T.; Zishiri, C.; Sandy, C.; Mutunzi, H.; Takarinda, K.; Owiti, P.; Mafaune, P.; Chonzi, P.

    2016-01-01

    Setting: In Zimbabwe, there are concerns about the management of tuberculosis (TB) patients with rifampicin (RMP) resistance diagnosed using Xpert® MTB/RIF. Objective: To assess linkages between diagnosis and treatment for these patients in Harare and Manicaland provinces in 2014. Design: A retrospective cohort study. Results: Of 20 329 Xpert assays conducted, 90% were successful, 11% detected Mycobacterium tuberculosis and 4.5% showed RMP resistance. Of 77 patients with RMP-resistant TB diagnosed by Xpert, 70% had samples sent to the reference laboratory for culture and drug susceptibility testing (CDST); 53% of the samples arrived. In 21% the samples showed M. tuberculosis growth, and in 17% the DST results were recorded, all of which confirmed RMP resistance. Of the 77 patients, 34 (44%) never started treatment for multidrug-resistant (MDR) TB, with documented reasons being death, loss to follow-up and incorrect treatment. Of the 43 patients who started MDR-TB treatment, 12 (71%) in Harare and 17 (65%) in Manicaland started within 2 weeks of diagnosis. Conclusion: Xpert has been rolled out successfully in two Zimbabwe provinces. However, the process of confirming CDST for Xpert-diagnosed RMP-resistant TB works poorly, and many patients are either delayed or never initiate MDR-TB treatment. These shortfalls must be addressed at the programmatic level. PMID:27358806

  16. Yield of intensified tuberculosis case-finding activities using Xpert® MTB/RIF among risk groups in Nepal

    PubMed Central

    Baral, S.; Shrestha, P.; Puri, M.; Kandel, S.; Lamichanne, B.; Elsey, H.; Brouwer, M.; Goel, S.; Chinnakali, P.

    2016-01-01

    Setting: Twenty-two districts of Nepal, where intensified case-finding (ICF) activities for tuberculosis (TB) were implemented among risk groups under the TB REACH initiative in collaboration with the National TB Programme from July 2013 to November 2015. Objectives: To assess the yield of TB screening using an algorithm with smear microscopy followed by Xpert® MTB/RIF. Design: A descriptive study using routinely collected data. Results: Of 145 679 individuals screened, 28 574 (19.6%) had presumptive TB; 1239 (4.3%) of these were diagnosed with TB and 1195 (96%) were initiated on anti-tuberculosis treatment. The yield of screening was highest among people living with the human immunodeficiency virus (PLHIV) (6.1%), followed by household contacts (3.5%) and urban slum dwellers (0.5%). Among other risk groups, such as prisoners, factory workers, refugees and individuals with diabetes, the yield was less than 0.5%. The number needed to screen to diagnose an active TB case was 17 for PLHIV, 29 for household contacts and 197 for urban slum dwellers. Of 11 525 patients from ICF and the routine programme, 112 (1%) were diagnosed with multidrug-resistant TB. Conclusion: There was a substantial yield of TB cases among risk groups such as PLHIV and household contacts. Although the yield in urban slum dwellers was found to be moderate, some intervention should nonetheless be targeted because of the large population and poor access to care in this group. PMID:27358808

  17. A Prospective Study of the Prevalence of Tuberculosis and Bacteraemia in Bangladeshi Children with Severe Malnutrition and Pneumonia Including an Evaluation of Xpert MTB/RIF Assay

    PubMed Central

    Chisti, Mohammod Jobayer; Graham, Stephen M.; Duke, Trevor; Ahmed, Tahmeed; Ashraf, Hasan; Faruque, Abu Syed Golam; La Vincente, Sophie; Banu, Sayera; Raqib, Rubhana; Salam, Mohammed Abdus

    2014-01-01

    Background Severe malnutrition is a risk factor for pneumonia due to a wide range of pathogens but aetiological data are limited and the role of Mycobacterium tuberculosis is uncertain. Methods We prospectively investigated severely malnourished young children (<5 years) with radiological pneumonia admitted over a 15-month period. Investigations included blood culture, sputa for microscopy and mycobacterial culture. Xpert MTB/RIF assay was introduced during the study. Study children were followed for 12 weeks following their discharge from the hospital. Results 405 eligible children were enrolled, with a median age of 10 months. Bacterial pathogens were isolated from blood culture in 18 (4.4%) children, of which 72% were Gram negatives. Tuberculosis was confirmed microbiologically in 7% (27/396) of children that provided sputum - 10 by culture, 21 by Xpert MTB/RIF assay, and 4 by both tests. The diagnostic yield from induced sputum was 6% compared to 3.5% from gastric aspirate. Sixty (16%) additional children had tuberculosis diagnosed clinically that was not microbiologically confirmed. Most confirmed tuberculosis cases did not have a positive contact history or positive tuberculin test. The sensitivity and specificity of Xpert MTB/RIF assay compared to culture was 67% (95% CI: 24–94) and 92% (95% CI: 87–95) respectively. Overall case-fatality rate was 17% and half of the deaths occurred in home following discharge from the hospital. Conclusion and Significance TB was common in severely malnourished Bangladeshi children with pneumonia. X-pert MTB/RIF assay provided higher case detection rate compared to sputum microscopy and culture. The high mortality among the study children underscores the need for further research aimed at improved case detection and management for better outcomes. PMID:24695758

  18. Multispectral VNIR Observations by the Opportunity Rover Pancam of Multiple Episodes of Aqueous Alteration in Marathon Valley, Endeavour Crater, Mars

    NASA Technical Reports Server (NTRS)

    Farrand, William H.; Bell, James F., III; Johnson, Jeffrey R.; Arvidson, Raymond E.; Mittlefehldt, David W.; Ruff, Steven W.; Rice, Melissa S.

    2016-01-01

    Since early 2015, the Mars Exploration Rover Opportunity has been exploring the break in the rim of Endeavour Crater dubbed Marathon Valley by the rover team. Marathon Valley was identified by orbital hyperspectral data from the MRO CRISM as having a relatively strong spectral feature in the 2.3 micrometer region indicative of an Mg or Fe-OH combination overtone absorption band indicative of smectite clay. Earlier in its mission, Opportunity examined the Matijevic Hill region on the more northerly Cape York crater rim segment and found evidence for smectite clays in a stratigraphically lower, pre-impact formed unit dubbed the Matijevic formation. However, the smectite exposures in Marathon Valley appear to be associated with the stratigraphically higher Shoemaker formation impact breccia. Evidence for alteration in this unit in Marathon Valley is provided by Pancam multispectral observations in the 430 to 1010 nm visible/near infrared (VNIR) spectral range. Sinuous troughs ("red zones") contain fragmented cobbles and pebbles displaying higher blue-to-red slopes, moderately higher 535 nm band depths, elevated 754 to 934 nm, and negative 934 to 1009 nm slopes. The lack of an absorption at 864 to 904 nm indicates the lack of crystalline red hematite in these red zones, but likely an enrichment in nanophase ferric oxides. The negative 934 to 1009 nm slope is potentially indicative of the presence of adsorbed or structurally bound water. A scuff in a red zone near the southern wall of Marathon Valley uncovered light-toned soils and a pebble with an 803 to 864 nm absorption resembling that of light-toned Fe-sulfate bearing soils uncovered by the Spirit rover in the Columbia Hills of Gusev crater. APXS chemical measurements indicated enrichments of Mg and S in the scuff soils and the pebble, Joseph Field, with the strongest 803 nm band- consistent with Mg and Fe sulfates. The presence of Fe and Mg sulfates can be interpreted as evidence of a potentially later episode of

  19. A 7-day oral supplementation with branched-chain amino acids was ineffective to prevent muscle damage during a marathon.

    PubMed

    Areces, Francisco; Salinero, Juan Jose; Abian-Vicen, Javier; González-Millán, Cristina; Gallo-Salazar, Cesar; Ruiz-Vicente, Diana; Lara, Beatriz; Del Coso, Juan

    2014-05-01

    The aim of this study was to determine the effectiveness of a 7-day oral supplementation with branched-chain amino acids (BCAA) to prevent muscle damage during a marathon. Forty-six experienced runners were randomly divided into two groups, one with BCAA supplementation (n = 25, supplemented with 5 g day(-1) of powdered 1:0.5:0.5 leucine:isoleucine:valine, during the 7 days prior to the competition) and the other as a control group (n = 21, supplemented with an isocaloric placebo). Before the marathon race and within 3 min of finishing, leg muscle power was measured with a maximal countermovement jump and a urine sample was obtained. During the race, running pace was measured by means of a time-chip. Myoglobin concentration was determined in the urine samples as an indirect marker of muscle damage. A visual analog scale (0-10 points) was used to assess leg muscle pain during the race. In the BCAA group, the mean running pace during the marathon was similar to the control group (3.3 ± 0.4 vs. 3.3 ± 0.5 m s(-1), respectively, 0.98). The pre- to post-race reduction in muscle power was similar in both BCAA and control groups (-23.0 ± 16.1 vs. -17.3 ± 13.8 %, P = 0.13). Post-race urine myoglobin concentration was similar in both BCAA and control groups (5.4 ± 7.5 vs. 4.5 ± 8.6 μg mL(-1), P = 0.70). Finally, there were no differences between groups in the perceived muscle pain during the race (6 ± 1 vs. 5 ± 1 points, P = 0.80). A 7-day supplementation of BCAA (5 g day(-1)) did not increase the running performance during a marathon. Furthermore, BCAA supplementation was ineffective to prevent muscle power loss, muscle damage or perceived muscle pain during a marathon race. PMID:24477835

  20. A 7-day oral supplementation with branched-chain amino acids was ineffective to prevent muscle damage during a marathon.

    PubMed

    Areces, Francisco; Salinero, Juan Jose; Abian-Vicen, Javier; González-Millán, Cristina; Gallo-Salazar, Cesar; Ruiz-Vicente, Diana; Lara, Beatriz; Del Coso, Juan

    2014-05-01

    The aim of this study was to determine the effectiveness of a 7-day oral supplementation with branched-chain amino acids (BCAA) to prevent muscle damage during a marathon. Forty-six experienced runners were randomly divided into two groups, one with BCAA supplementation (n = 25, supplemented with 5 g day(-1) of powdered 1:0.5:0.5 leucine:isoleucine:valine, during the 7 days prior to the competition) and the other as a control group (n = 21, supplemented with an isocaloric placebo). Before the marathon race and within 3 min of finishing, leg muscle power was measured with a maximal countermovement jump and a urine sample was obtained. During the race, running pace was measured by means of a time-chip. Myoglobin concentration was determined in the urine samples as an indirect marker of muscle damage. A visual analog scale (0-10 points) was used to assess leg muscle pain during the race. In the BCAA group, the mean running pace during the marathon was similar to the control group (3.3 ± 0.4 vs. 3.3 ± 0.5 m s(-1), respectively, 0.98). The pre- to post-race reduction in muscle power was similar in both BCAA and control groups (-23.0 ± 16.1 vs. -17.3 ± 13.8 %, P = 0.13). Post-race urine myoglobin concentration was similar in both BCAA and control groups (5.4 ± 7.5 vs. 4.5 ± 8.6 μg mL(-1), P = 0.70). Finally, there were no differences between groups in the perceived muscle pain during the race (6 ± 1 vs. 5 ± 1 points, P = 0.80). A 7-day supplementation of BCAA (5 g day(-1)) did not increase the running performance during a marathon. Furthermore, BCAA supplementation was ineffective to prevent muscle power loss, muscle damage or perceived muscle pain during a marathon race.

  1. Effect of BETA 1, 3/1, 6 GLUCAN on Upper Respiratory Tract Infection Symptoms and Mood State in Marathon Athletes.

    PubMed

    Talbott, Shawn; Talbott, Julie

    2009-01-01

    This was a placebo-controlled, double-blind study designed to evaluate the effect of a commercially available dietary supplement on upper-respiratory tract symptoms (URTI) and mood state. Seventy-five marathon runners (35 men, 40 women) ranging in age from 18-53 years, mean age: 36 ± 9, self-administered placebo, 250 mg or 500 mg of BETA 1,3/1,6 GLUCAN (commercial name Wellmune WGP(®)) daily during the 4 week post-marathon trial period following the 2007 Carlsbad Marathon. Subjects filled out the profile of mood state (POMS) assessment and a questionnaire style health log measuring health status and URTI symptoms after 2- and 4-week treatment administrations. During the course of the 4-week study, subjects in the treatment groups (250 mg and 500 mg BETA-GLUCAN per day) reported significantly fewer URTI symptoms, better overall health and decreased confusion, fatigue, tension, and anger, and increased vigor based on the POMS survey compared to placebo. BETA-GLUCAN may prevent URTI symptoms, and improve overall health and mood following a competitive marathon. Key pointsBeta-Glucan supplementation maintains immune function in endurance athletes.Beta-Glucan supplementation reduces post-exercise URTIs in marathon runners.Maintenance of post-exercise immune function is associated with improved mood state, including reduced fatigue and increased vigor in athletes.

  2. Effect of BETA 1, 3/1, 6 GLUCAN on Upper Respiratory Tract Infection Symptoms and Mood State in Marathon Athletes

    PubMed Central

    Talbott, Shawn; Talbott, Julie

    2009-01-01

    This was a placebo-controlled, double-blind study designed to evaluate the effect of a commercially available dietary supplement on upper-respiratory tract symptoms (URTI) and mood state. Seventy-five marathon runners (35 men, 40 women) ranging in age from 18-53 years, mean age: 36 ± 9, self-administered placebo, 250 mg or 500 mg of BETA 1,3/1,6 GLUCAN (commercial name Wellmune WGP®) daily during the 4 week post-marathon trial period following the 2007 Carlsbad Marathon. Subjects filled out the profile of mood state (POMS) assessment and a questionnaire style health log measuring health status and URTI symptoms after 2- and 4-week treatment administrations. During the course of the 4-week study, subjects in the treatment groups (250 mg and 500 mg BETA-GLUCAN per day) reported significantly fewer URTI symptoms, better overall health and decreased confusion, fatigue, tension, and anger, and increased vigor based on the POMS survey compared to placebo. BETA-GLUCAN may prevent URTI symptoms, and improve overall health and mood following a competitive marathon. Key points Beta-Glucan supplementation maintains immune function in endurance athletes. Beta-Glucan supplementation reduces post-exercise URTIs in marathon runners. Maintenance of post-exercise immune function is associated with improved mood state, including reduced fatigue and increased vigor in athletes. PMID:24149590

  3. Alterations in postural control during the world's most challenging mountain ultra-marathon.

    PubMed

    Degache, Francis; Van Zaen, Jérôme; Oehen, Lukas; Guex, Kenny; Trabucchi, Pietro; Millet, Grégoire; Millet, Gégoire

    2014-01-01

    We investigated postural control (PC) effects of a mountain ultra-marathon (MUM): a 330-km trail run with 24000 m of positive and negative change in elevation. PC was assessed prior to (PRE), during (MID) and after (POST) the MUM in experienced ultra-marathon runners (n = 18; finish time = 126 ± 16 h) and in a control group (n = 8) with a similar level of sleep deprivation. Subjects were instructed to stand upright on a posturographic platform over a period of 51.2 seconds using a double-leg stance under two test conditions: eyes open (EO) and eyes closed (EC). Traditional measures of postural stability (center of pressure trajectory analysis) and stabilogram-diffusion analysis (SDA) parameters were analysed. For the SDA, a significantly greater short-term effective diffusion was found at POST compared with PRE in the medio-lateral (ML; Dxs) and antero-posterior (AP) directions (Dys) in runners (p<0.05) The critical time interval (Ctx) in the ML direction was significantly higher at MID (p<0.001) and POST (p<0.05) than at PRE in runners. At MID (p<0.001) and POST (p<0.05), there was a significant difference between the two groups. The critical displacement (Cdx) in the ML was significantly higher at MID and at POST (p<0.001) compared with PRE for runners. A significant difference in Cdx was observed between groups in EO at MID (p<0.05) and POST (p<0.005) in the ML direction and in EC at POST in the ML and AP directions (p<0.05). Our findings revealed significant effects of fatigue on PC in runners, including, a significant increase in Ctx (critical time in ML plan) in EO and EC conditions. Thus, runners take longer to stabilise their body at POST than at MID. It is likely that the mountainous characteristics of MUM (unstable ground, primarily uphill/downhill running, and altitude) increase this fatigue, leading to difficulty in maintaining balance. PMID:24465417

  4. Can neuromuscular fatigue explain running strategies and performance in ultra-marathons?: the flush model.

    PubMed

    Millet, Guillaume Y

    2011-06-01

    While the industrialized world adopts a largely sedentary lifestyle, ultra-marathon running races have become increasingly popular in the last few years in many countries. The ability to run long distances is also considered to have played a role in human evolution. This makes the issue of ultra-long distance physiology important. In the ability to run multiples of 10 km (up to 1000 km in one stage), fatigue resistance is critical. Fatigue is generally defined as strength loss (i.e. a decrease in maximal voluntary contraction [MVC]), which is known to be dependent on the type of exercise. Critical task variables include the intensity and duration of the activity, both of which are very specific to ultra-endurance sports. They also include the muscle groups involved and the type of muscle contraction, two variables that depend on the sport under consideration. The first part of this article focuses on the central and peripheral causes of the alterations to neuromuscular function that occur in ultra-marathon running. Neuromuscular function evaluation requires measurements of MVCs and maximal electrical/magnetic stimulations; these provide an insight into the factors in the CNS and the muscles implicated in fatigue. However, such measurements do not necessarily predict how muscle function may influence ultra-endurance running and whether this has an effect on speed regulation during a real competition (i.e. when pacing strategies are involved). In other words, the nature of the relationship between fatigue as measured using maximal contractions/stimulation and submaximal performance limitation/regulation is questionable. To investigate this issue, we are suggesting a holistic model in the second part of this article. This model can be applied to all endurance activities, but is specifically adapted to ultra-endurance running: the flush model. This model has the following four components: (i) the ball-cock (or buoy), which can be compared with the rate of perceived

  5. Piloting Upfront Xpert MTB/RIF Testing on Various Specimens under Programmatic Conditions for Diagnosis of TB & DR-TB in Paediatric Population

    PubMed Central

    Raizada, Neeraj; Sachdeva, Kuldeep Singh; Swaminathan, Soumya; Kulsange, Shubhangi; Khaparde, Sunil D.; Nair, Sreenivas Achuthan; Khanna, Ashwani; Chopra, Kamal Kishore; Hanif, Mahmud; Sethi, Gulshan Rai; Umadevi, K. R.; Keshav Chander, G.; Saha, Brojakishore; Shah, Amar; Parmar, Malik; Ghediya, Mayank; Jaju, Jyoti; Boehme, Catharina; Paramasivan, Chinnambedu Nainarappan

    2015-01-01

    Background India accounts for one-fifth of the global TB incidence. While the exact burden of childhood TB is not known, TB remains one of the leading causes of childhood mortality in India. Bacteriological confirmation of TB in children is challenging due to difficulty in obtaining quality specimens, in the absence of which diagnosis is largely based on clinical judgement. While testing multiple specimens can potentially contribute to higher proportion of laboratory confirmed paediatric TB cases, lack of high sensitivity tests adds to the diagnostic challenge. We describe here our experiences in piloting upfront Xpert MTB/RIF testing, for diagnosis of TB in paediatric population in respiratory and extra pulmonary specimens, as recently recommended by WHO. Method Xpert MTB/RIF testing was offered to all paediatric (0–14 years) presumptive TB cases (both pulmonary and extra-pulmonary) seeking care at public and private health facilities in the project areas covering 4 cities of India. Results Under this pilot project, 8,370 paediatric presumptive TB & presumptive DR-TB cases were tested between April and–November 2014. Overall, 9,149 specimens were tested, of which 4,445 (48.6%) were non-sputum specimens. Xpert MTB/RIF gave 9,083 (99.2%, CI 99.0–99.4) valid results. Of the 8,143 presumptive TB cases enrolled, 517 (6.3%, CI 5.8–6.9) were bacteriologically confirmed. TB detection rates were two fold higher with Xpert MTB/RIF as compared to smear microscopy. Further, a total of 60 rifampicin resistant TB cases were detected, of which 38 were detected among 512 presumptive TB cases while 22 were detected amongst 227 presumptive DR-TB cases tested under the project. Conclusion Xpert MTB/RIF with advantages of quick turnaround testing-time, high proportion of interpretable results and feasibility of rapid rollout, substantially improved the diagnosis of bacteriologically confirmed TB in children, while simultaneously detecting rifampicin resistance. PMID:26469691

  6. Xpert MTB/RIF Assay Shortens Airborne Isolation for Hospitalized Patients With Presumptive Tuberculosis in the United States

    PubMed Central

    Lippincott, Christopher K.; Miller, Melissa B.; Popowitch, Elena B.; Hanrahan, Colleen F.; Van Rie, Annelies

    2014-01-01

    Background. In the United States, individuals with presumptive pulmonary tuberculosis are placed in airborne infection isolation (AII) and assessed by smear microscopy on 3 respiratory specimens collected 8–24 hours apart. Xpert MTB/RIF assay (Xpert) on 1, 2, or 3 specimens may be more efficient for determining AII discontinuation. Methods. This single-center, observational cohort study of inpatients with presumptive pulmonary tuberculosis enrolled adults with 1 or more sputum specimens submitted for smear microscopy. Smear microscopy and Xpert were performed on each sputum specimen. Clinicians were blinded to Xpert results. The primary endpoint was AII duration. Secondary endpoints were laboratory processing time, strategy-based tuberculosis detection, and sensitivity and specificity. Results. Among 207 subjects, the median AII duration was 68.0 hours (interquartile range [IQR], 47.1–97.5) for smear microscopy compared with 20.8 hours (IQR, 16.8–32.0) for the 1-specimen Xpert, 41.2 hours (IQR, 26.6–54.8) for the 2-specimen Xpert, and 54.0 hours (IQR, 43.3–80.0) for the 3-specimen Xpert strategies (P ≤ .004). Median laboratory processing time for smear microscopy was 2.5 times as long as Xpert (P < .001). The 2- and 3-specimen Xpert and smear microscopy strategies captured all 6 tuberculosis cases. The 1-specimen Xpert strategy missed 1 case. No difference was observed between smear microscopy and Xpert in sensitivity or specificity for detection of Mycobacterium tuberculosis. Conclusions. Xpert-based strategies significantly reduced AII duration compared with the smear-based strategy. The 2-specimen Xpert strategy was most efficient in minimizing AII time while identifying all tuberculosis cases among individuals with presumptive tuberculosis in this low-burden setting. PMID:24729506

  7. The Boston Marathon Bombings Mass Casualty Incident: One Emergency Department's Information Systems Challenges and Opportunities.

    PubMed

    Landman, Adam; Teich, Jonathan M; Pruitt, Peter; Moore, Samantha E; Theriault, Jennifer; Dorisca, Elizabeth; Harris, Sheila; Crim, Heidi; Lurie, Nicole; Goralnick, Eric

    2015-07-01

    Emergency department (ED) information systems are designed to support efficient and safe emergency care. These same systems often play a critical role in disasters to facilitate real-time situation awareness, information management, and communication. In this article, we describe one ED's experiences with ED information systems during the April 2013 Boston Marathon bombings. During postevent debriefings, staff shared that our ED information systems and workflow did not optimally support this incident; we found challenges with our unidentified patient naming convention, real-time situational awareness of patient location, and documentation of assessments, orders, and procedures. As a result, before our next mass gathering event, we changed our unidentified patient naming convention to more clearly distinguish multiple, simultaneous, unidentified patients. We also made changes to the disaster registration workflow and enhanced roles and responsibilities for updating electronic systems. Health systems should conduct disaster drills using their ED information systems to identify inefficiencies before an actual incident. ED information systems may require enhancements to better support disasters. Newer technologies, such as radiofrequency identification, could further improve disaster information management and communication but require careful evaluation and implementation into daily ED workflow.

  8. Blast Injuries: From Improvised Explosive Device Blasts to the Boston Marathon Bombing.

    PubMed

    Singh, Ajay K; Ditkofsky, Noah G; York, John D; Abujudeh, Hani H; Avery, Laura A; Brunner, John F; Sodickson, Aaron D; Lev, Michael H

    2016-01-01

    Although most trauma centers have experience with the imaging and management of gunshot wounds, in most regions blast wounds such as the ones encountered in terrorist attacks with the use of improvised explosive devices (IEDs) are infrequently encountered outside the battlefield. As global terrorism becomes a greater concern, it is important that radiologists, particularly those working in urban trauma centers, be aware of the mechanisms of injury and the spectrum of primary, secondary, tertiary, and quaternary blast injury patterns. Primary blast injuries are caused by barotrauma from the initial increased pressure of the explosive detonation and the rarefaction of the atmosphere immediately afterward. Secondary blast injuries are caused by debris carried by the blast wind and most often result in penetrating trauma from small shrapnel. Tertiary blast injuries are caused by the physical displacement of the victim and the wide variety of blunt or penetrating trauma sustained as a result of the patient impacting immovable objects such as surrounding cars, walls, or fences. Quaternary blast injuries include all other injuries, such as burns, crush injuries, and inhalational injuries. Radiography is considered the initial imaging modality for assessment of shrapnel and fractures. Computed tomography is the optimal test to assess penetrating chest, abdominal, and head trauma. The mechanism of blast injuries and the imaging experience of the victims of the Boston Marathon bombing are detailed, as well as musculoskeletal, neurologic, gastrointestinal, and pulmonary injury patterns from blast injuries.

  9. Anthropometric measurements for assessing insulin sensitivity on patients with metabolic syndrome, sedentaries and marathoners.

    PubMed

    Severeyn, Erika; Wong, Sara; Herrera, Hector; Altuve, Miguel

    2015-08-01

    The diagnosis of low insulin sensitivity is commonly done through the HOMA-IR index, in which fasting insulin and glucose blood levels are evaluated. Insulin and blood glucose levels are used for insulin sensitivity assessment by surrogate methods (HOMA-IR, Matsuda, etc), but anthropometric measurements like body weight, height and waist circumference are not considered, even if these variables also are related to low insulin sensitivity and metabolic syndrome. In this study we evaluate the impact of anthropometric measurements on the HOMA-IR, Matsuda and Caumo indexes to estimate insulin sensitivity. Specifically, we compare insulin sensitivity indexes with and without the anthropometric measurements in their equations on three different groups: patients with metabolic syndrome, sedentaries and marathoners. Results show relationships between anthropometric variables and insulin sensitivity indexes. On the other hand, subjects are mapped differently for insulin sensitivity assessment when anthropometric variables are taken into account. In addition, subjects diagnosed with normal insulin sensitivity could be considered as having low insulin sensitivity when anthropometric variables are considered.

  10. Blast Injuries: From Improvised Explosive Device Blasts to the Boston Marathon Bombing.

    PubMed

    Singh, Ajay K; Ditkofsky, Noah G; York, John D; Abujudeh, Hani H; Avery, Laura A; Brunner, John F; Sodickson, Aaron D; Lev, Michael H

    2016-01-01

    Although most trauma centers have experience with the imaging and management of gunshot wounds, in most regions blast wounds such as the ones encountered in terrorist attacks with the use of improvised explosive devices (IEDs) are infrequently encountered outside the battlefield. As global terrorism becomes a greater concern, it is important that radiologists, particularly those working in urban trauma centers, be aware of the mechanisms of injury and the spectrum of primary, secondary, tertiary, and quaternary blast injury patterns. Primary blast injuries are caused by barotrauma from the initial increased pressure of the explosive detonation and the rarefaction of the atmosphere immediately afterward. Secondary blast injuries are caused by debris carried by the blast wind and most often result in penetrating trauma from small shrapnel. Tertiary blast injuries are caused by the physical displacement of the victim and the wide variety of blunt or penetrating trauma sustained as a result of the patient impacting immovable objects such as surrounding cars, walls, or fences. Quaternary blast injuries include all other injuries, such as burns, crush injuries, and inhalational injuries. Radiography is considered the initial imaging modality for assessment of shrapnel and fractures. Computed tomography is the optimal test to assess penetrating chest, abdominal, and head trauma. The mechanism of blast injuries and the imaging experience of the victims of the Boston Marathon bombing are detailed, as well as musculoskeletal, neurologic, gastrointestinal, and pulmonary injury patterns from blast injuries. PMID:26761543

  11. Airborne and ground reconnaissance of part of the syenite complex near Wausau, Marathon county, Wisconsin

    USGS Publications Warehouse

    Vickers, R.C.

    1955-01-01

    Airborne and ground reconnaissance for radioactive minerals in part of the syenite complex near Wausau, Marathon county, Wis., found 12 radioactive mineral localities. The rocks in the area are of Precambrian age and consist of syenite and nepheline syenite, which have intruded older granite, greenstone, quartzite, and argillite. There are very few outcrops, and much of the bedrock is deeply weathered and covered by residual soil. Thorium-bearing zircon pegatite float was found within the area of syenite and nepheline syenite at four localities. Reddish-brown euhedral to subeuhedral crystals of well-zoned zircon (variety cyrtolite) comprise more than 40 percent of some of the specimens. The radioactive mineral at four localities outside the area of syneites was identified as thorogummite, which occurred in nodular masses in residual soil. Alinement of the thorogummite float and associated radioactivity suggests that the thorogummite has resulted from weathering of narrow veins or pegmatites containing thorium-bearing minerals. Unidentified thorium-bearing minerals were found at three localities, and a specimen of allanite weighing about 2 pounds was found at one locality. Shallow trenches at two of the largest radioactivity anomalies showed that the radioactive material extended down into weathered bedrock. The occurrences might warrant additional physical exploration should there be sufficient demand for thorium. Further reconnaissance in the area would probably result in the discovery of additional occurrences.

  12. Media Use and Exposure to Graphic Content in the Week Following the Boston Marathon Bombings.

    PubMed

    Jones, Nickolas M; Garfin, Dana Rose; Holman, E Alison; Silver, Roxane Cohen

    2016-09-01

    Traditional and new media inform and expose the public to potentially distressing graphic content following disasters, but predictors of media use have received limited attention. We examine media-use patterns after the Boston Marathon bombings (BMB) in a representative national U.S. sample (n = 2888), with representative oversamples from metropolitan Boston (n = 845) and New York City (n = 941). Respondents completed an Internet-based survey 2-4 weeks post-BMB. Use of traditional media was correlated with older age, prior indirect media-based exposure to collective traumas, and direct BMB exposure. New media use was correlated with younger age and prior direct exposure to collective traumas. Increased television and online news viewing were associated with exposure to more graphic content. The relationship between traditional and new media was stronger for young adults than all other age groups. We offer insights about the relationship between prior collective trauma exposures and media use following subsequent disasters and identify media sources likely to expose people to graphic content. PMID:27616665

  13. Psychological effects of the marathon bombing on Boston-area veterans with posttraumatic stress disorder.

    PubMed

    Miller, Mark W; Wolf, Erika J; Hein, Christina; Prince, Lauren; Reardon, Annemarie F

    2013-12-01

    This study examined the psychological impact of the Boston Marathon bombing using data from an ongoing longitudinal study of Boston-area veterans with posttraumatic stress disorder (PTSD; N = 71). Participants were assessed by telephone within 1 week of the end of the event; 42.3% of participants reported being personally affected by the bombings and/or the manhunt that followed. The majority of them reported that the bombing reminded them of their own traumas and/or caused other emotional distress. Examination of change in posttraumatic stress disorder (PTSD) symptoms from a prebombing assessment an average of 2 months earlier to 1 week after the event revealed no significant change in symptoms across the sample as a whole. However, examination of patterns of change at the individual level revealed significant correlations (r = .33; p = .005) between distress at the time of the event and change in total PTSD symptom severity, with this effect accounted for primarily by increases in intrusion and avoidance symptoms (rs = .35 and .31, ps = .002 and .008, respectively). Findings of this study should raise awareness of the potential impact of terror attacks, mass shootings, and other events of this type on the well-being of individuals with histories of trauma and/or pre-existing PTSD.

  14. Psychological effects of the marathon bombing on Boston-area veterans with posttraumatic stress disorder.

    PubMed

    Miller, Mark W; Wolf, Erika J; Hein, Christina; Prince, Lauren; Reardon, Annemarie F

    2013-12-01

    This study examined the psychological impact of the Boston Marathon bombing using data from an ongoing longitudinal study of Boston-area veterans with posttraumatic stress disorder (PTSD; N = 71). Participants were assessed by telephone within 1 week of the end of the event; 42.3% of participants reported being personally affected by the bombings and/or the manhunt that followed. The majority of them reported that the bombing reminded them of their own traumas and/or caused other emotional distress. Examination of change in posttraumatic stress disorder (PTSD) symptoms from a prebombing assessment an average of 2 months earlier to 1 week after the event revealed no significant change in symptoms across the sample as a whole. However, examination of patterns of change at the individual level revealed significant correlations (r = .33; p = .005) between distress at the time of the event and change in total PTSD symptom severity, with this effect accounted for primarily by increases in intrusion and avoidance symptoms (rs = .35 and .31, ps = .002 and .008, respectively). Findings of this study should raise awareness of the potential impact of terror attacks, mass shootings, and other events of this type on the well-being of individuals with histories of trauma and/or pre-existing PTSD. PMID:24343753

  15. Media Use and Exposure to Graphic Content in the Week Following the Boston Marathon Bombings.

    PubMed

    Jones, Nickolas M; Garfin, Dana Rose; Holman, E Alison; Silver, Roxane Cohen

    2016-09-01

    Traditional and new media inform and expose the public to potentially distressing graphic content following disasters, but predictors of media use have received limited attention. We examine media-use patterns after the Boston Marathon bombings (BMB) in a representative national U.S. sample (n = 2888), with representative oversamples from metropolitan Boston (n = 845) and New York City (n = 941). Respondents completed an Internet-based survey 2-4 weeks post-BMB. Use of traditional media was correlated with older age, prior indirect media-based exposure to collective traumas, and direct BMB exposure. New media use was correlated with younger age and prior direct exposure to collective traumas. Increased television and online news viewing were associated with exposure to more graphic content. The relationship between traditional and new media was stronger for young adults than all other age groups. We offer insights about the relationship between prior collective trauma exposures and media use following subsequent disasters and identify media sources likely to expose people to graphic content.

  16. Exertional heat stroke during a cool weather marathon: a case study.

    PubMed

    Roberts, William O

    2006-07-01

    A well-trained male runner in his late 30s collapsed 10 m before the finish line, nearly completing the 42.1-km marathon course in 3 h, 15 min. He was responsive to pain, agitated, diaphoretic, and unable to walk. The race start temperature was 6 degrees C (43 degrees F) with relative humidity of 99% and the 3-h temperature was 9.5 degrees C (49 degrees F) with a 62% relative humidity. Approximately 27 min after his collapse, his rectal temperature in the emergency department was 40.7 degrees C (105.3 degrees F), and his failing respiratory status required intubation. His initial Glasgow coma score was 6-7 of 15. His renal output was minimal until he was cooled and given a large fluid flush. His initial echocardiogram showed a "stunned" myocardium with an ejection fraction of 35%. He had a viral syndrome the week prior to the race and was paced by a "fresh" runner the last 16 km of the race. He left the hospital in 5 d and has now returned to running without problems, although several months passed before he felt well while exercising. Exertional heat stroke can occur in cool conditions, and rectal temperature should be checked in all collapsed runners who do not progress with rapid recovery of vital signs and cognitive function. Runners should be instructed not to compete when ill and should not use nonparticipant pacers during the runs.

  17. Influence of a 100-km ultra-marathon on hepatitis B carrier runners.

    PubMed

    Chiu, Y-H; Hou, S-K; How, C-K; Li, L-H; Kao, W-F; Yang, C-C; Chou, S-L; Shiau, Y-T S; Lam, C; Chen, R-J

    2013-09-01

    This study compares the serological markers between runners who are hepatitis B virus carries (HBVc) and runners who are non-HBVc in a 100-km ultra-marathon race. Blood samples of 8 HBVc and 18 non-HBVc runners were drawn 1 week before, immediately following, and 24 h after the race. Samples were analyzed and compared between the 2 groups for liver function tests, muscle damage markers and oxidative stress cytokines. For HBVc runners, HBV-DNA (hepatitis B virus-deoxyribonucleic acid) levels were also evaluated for virus reactivation. The results demonstrate a statistically significant increase in both immediate and 24-h post-race values for alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), compared with pre-race values. No statistically significant difference was observed between the 2 groups for the values of AST, LDH, CK, hs-CRP, IL-6 and TNF-α either before or after the race. There was also no statistically significant change in the levels of HBV-DNA in HBVc runners. These findings suggest that HBVc runners do not have higher risks of liver function impairment, muscle breakdown and inflammatory response compared to non-HBVc runners in such endurance races. PMID:23444084

  18. Physical Activity Enhances Metabolic Fitness Independently of Cardiorespiratory Fitness in Marathon Runners

    PubMed Central

    Laye, M. J.; Nielsen, M. B.; Hansen, L. S.; Knudsen, T.; Pedersen, B. K.

    2015-01-01

    High levels of cardiovascular fitness (CRF) and physical activity (PA) are associated with decreased mortality and risk to develop metabolic diseases. The independent contributions of CRF and PA to metabolic disease risk factors are unknown. We tested the hypothesis that runners who run consistently >50 km/wk and/or >2 marathons/yr for the last 5 years have superior metabolic fitness compared to matched sedentary subjects (CRF, age, gender, and BMI). Case-control recruitment of 31 pairs of runner-sedentary subjects identified 10 matched pairs with similar VO2max (mL/min/kg) (similar-VO2max). The similar-VO2max group was compared with a group of age, gender, and BMI matched pairs who had the largest difference in VO2max (different-VO2max). Primary outcomes that defined metabolic fitness including insulin response to an oral glucose tolerance test, fasting lipids, and fasting insulin were superior in runners versus sedentary controls despite similar VO2max. Furthermore, performance (velocity at VO2max, running economy), improved exercise metabolism (lactate threshold), and skeletal muscle levels of mitochondrial proteins were superior in runners versus sedentary controls with similar VO2max. In conclusion subjects with a high amount of PA have more positive metabolic health parameters independent of CRF. PA is thus a good marker against metabolic diseases. PMID:25821340

  19. Effect of marathon run and air travel on pre- and post-run soluble d-dimer, microparticle procoagulant activity, and p-selectin levels.

    PubMed

    Parker, Beth A; Augeri, Amanda L; Capizzi, Jeffrey A; Ballard, Kevin D; Kupchak, Brian R; Volek, Jeffrey S; Troyanos, Christopher; Kriz, Peter; D'Hemecourt, Pierre; Thompson, Paul D

    2012-05-15

    D-dimer, microparticles, and p-selectin are venous thrombotic risk markers. Elevated p-selectin is associated with increased cardiovascular events. We examined the effects of exercise and air travel on the markers of vascular risk in marathon runners. Forty-one persons participating in the 114th Boston Marathon (April 19, 2010) were divided into travel (n = 23) and nontravel "control" (n = 18) groups according to whether they lived more than a 4-hour plane flight or less than a 2-hour car trip from Boston. The subjects provided venous blood samples the day before, immediately after, and after returning home the day after the marathon. The blood was analyzed for soluble d-dimer, microparticle procoagulant activity, and p-selectin. D-dimer levels increased more before to immediately after (142 ± 83 to 387 ± 196 ng/mL) in the travel group than in the controls (85 ± 26 to 233 ± 95 ng/mL; p = 0.02). Moreover, 6 travel subjects versus 0 controls had d-dimer values >500 ng/mL after returning home the day after the marathon, the clinical threshold for excluding venous thrombosis (p = 0.03). P-selectin increased with exercise (p <0.01) regardless of travel (p = 0.09) but age was related to p-selectin (p = 0.01) such that older subjects exhibited greater p-selectin values before (r(2) = 0.14; p = 0.02) and after returning home the day after the marathon (r(2) = 0.16, p = 0.01). In conclusion, the combination of exercise and travel increases venous and arterial thrombotic risk. Moreover, the p-selectin levels at rest and after exercise were greater with age. These results might explain the reports of venous thrombosis with air travel after athletic events and the reports of cardiac events in older participants running marathons.

  20. Self-selecting fluid intake while maintaining high carbohydrate availability does not impair half-marathon performance.

    PubMed

    Lee, M J C; Hammond, K M; Vasdev, A; Poole, K L; Impey, S G; Close, G L; Morton, J P

    2014-12-01

    We aimed to test the hypothesis that self-selecting fluid intake but maintaining high exogenous CHO availability (60 g/h) does not compromise half-marathon performance. 15 participants completed 3 half-marathons while drinking a 6% CHO solution to guidelines (DRINK) or a non-caloric solution in self-selected volumes when consuming 3×glucose (20 g) gels (G-GEL) or glucose-fructose (13 g glucose+7 g fructose) gels (GF-GEL) per hour. Fluid intake (DRINK: 1 557±182, G-GEL: 473±234, GF-GEL: 404±144 ml) and percent body mass loss (DRINK: - 0.8±0.9, G-GEL: - 2.0±0.6, GF-GEL: -2.3±1.1) were different (P<0.05) between conditions, though race time did not differ (DRINK: 110.6±14.4, G-GEL: 110.3±14.6, GF-GEL: 113.7±12.8 min). In G-GEL, there was a positive correlation (P<0.05) between body mass loss and race time. Plasma glucose was lower (P<0.05) in GF-GEL compared with other conditions, and total CHO oxidation (DRINK: 3.2±0.5, G-GEL: 3.0±0.4, GF-GEL: 2.6±0.4 g/min) was lower (P=0.06) in this trial. Self-selecting fluid intake but maintaining high CHO availability does not impair half-marathon performance. Additionally, consuming glucose-fructose mixtures in sub-optimal amounts reduces plasma glucose and total rates of CHO oxidation.

  1. Energy balance, macronutrient intake, and hydration status during a 1,230 km ultra-endurance bike marathon.

    PubMed

    Geesmann, Bjoern; Mester, Joachim; Koehler, Karsten

    2014-10-01

    Athletes competing in ultra-endurance events are advised to meet energy requirements, to supply appropriate amounts of carbohydrates (CHO), and to be adequately hydrated before and during exercise. In practice, these recommendations may not be followed because of satiety, gastrointestinal discomfort, and fatigue. The purpose of the study was to assess energy balance, macronutrient intake and hydration status before and during a 1,230-km bike marathon. A group of 14 well-trained participants (VO2max: 63.2 ± 3.3 ml/kg/min) completed the marathon after 42:47 hr. Ad libitum food and fluid intake were monitored throughout the event. Energy expenditure (EE) was derived from power output and urine and blood markers were collected before the start, after 310, 618, and 921 km, after the finish, and 12 hr after the finish. Energy intake (EI; 19,749 ± 4,502 kcal) was lower than EE (25,303 ± 2,436 kcal) in 12 of 14 athletes. EI and CHO intake (average: 57.1 ± 17.7 g/hr) decreased significantly after km 618 (p < .05). Participants ingested on average 392 ± 85 ml/hr of fluid, but fluid intake decreased after km 618 (p < .05). Hydration appeared suboptimal before the start (urine specific gravity: 1.022 ± 0.010 g/ml) but did not change significantly throughout the event. The results show that participants failed to maintain in energy balance and that CHO and fluid intake dropped below recommended values during the second half of the bike marathon. Individual strategies to overcome satiety and fatigue may be necessary to improve eating and drinking behavior during prolonged ultra-endurance exercise.

  2. Whole blood coagulation and platelet activation in the athlete: A comparison of marathon, triathlon and long distance cycling

    PubMed Central

    2010-01-01

    Introduction Serious thrombembolic events occur in otherwise healthy marathon athletes during competition. We tested the hypothesis that during heavy endurance sports coagulation and platelets are activated depending on the type of endurance sport with respect to its running fraction. Materials and Methods 68 healthy athletes participating in marathon (MAR, running 42 km, n = 24), triathlon (TRI, swimming 2.5 km + cycling 90 km + running 21 km, n = 22), and long distance cycling (CYC, 151 km, n = 22) were included in the study. Blood samples were taken before and immediately after completion of competition to perform rotational thrombelastometry. We assessed coagulation time (CT), maximum clot firmness (MCF) after intrinsically activation and fibrin polymerization (FIBTEM). Furthermore, platelet aggregation was tested after activation with ADP and thrombin activating peptide 6 (TRAP) by using multiple platelet function analyzer. Results Complete data sets were obtained in 58 athletes (MAR: n = 20, TRI: n = 19, CYC: n = 19). CT significantly decreased in all groups (MAR -9.9%, TRI -8.3%, CYC -7.4%) without differences between groups. In parallel, MCF (MAR +7.4%, TRI +6.1%, CYC +8.3%) and fibrin polymerization (MAR +14.7%, TRI +6.1%, CYC +8.3%) were significantly increased in all groups. However, platelets were only activated during MAR and TRI as indicated by increased AUC during TRAP-activation (MAR +15.8%) and increased AUC during ADP-activation in MAR (+50.3%) and TRI (+57.5%). Discussion While coagulation is activated during physical activity irrespective of type we observed significant platelet activation only during marathon and to a lesser extent during triathlon. We speculate that prolonged running may increase platelet activity, possibly, due to mechanical alteration. Thus, particularly prolonged running may increase the risk of thrombembolic incidents in running athletes. PMID:20452885

  3. [Effect of ultra-endurance swimming on body composition--marathon swim 2006 from Rapperswil to Zurich].

    PubMed

    Knechtle, B; Baumann, B; Knechtle, P

    2007-04-11

    We measured, during a marathon swimming event 2006 in the lake of Zurich, load intensity, energy intake, energy expenditure and impact on both muscle and fat mass in a trained long-distance swimmer. The swimmer had a load intensity of 125 bpm corresponding to 51% VO2(max). Despite adequate energy intake during the load, an energy deficit of 500 kcal per hour occurred, which resulted in a loss of 1.1 kg body mass within 9 hours of swimming. PMID:17506388

  4. Why we are here: early reflections on the role of reconstructive plastic surgery in the 2013 Boston marathon bombings.

    PubMed

    Carty, Matthew J; Caterson, Edward J; Caterson, Stephanie A; Chun, Yoon S; Erdmann-Sager, Jessica; Hadad, Ivan; Halvorson, Eric G; Orgill, Dennis P; Sampson, Christian E; Talbot, Simon G; Theman, Todd; Eriksson, Elof

    2013-12-01

    The 2013 Boston Marathon bombings resulted in a large and unexpected influx of patients requiring acute multidisciplinary surgical care. The authors describe the surgical management experience of these patients at Brigham & Women's Hospital and Brigham & Women's Faulkner Hospital, with a particular focus on the important role played by reconstructive plastic surgery. The authors suggest that this experience illustrates the value of reconstructive plastic surgery in the treatment of these patients specifically and of trauma patients in general, and argue for the increasing importance of promoting our identity as a specialty.

  5. An increased fluid intake leads to feet swelling in 100-km ultra-marathoners - an observational field study

    PubMed Central

    2012-01-01

    Background An association between fluid intake and changes in volumes of the upper and lower limb has been described in 100-km ultra-marathoners. The purpose of the present study was (i) to investigate the association between fluid intake and a potential development of peripheral oedemas leading to an increase of the feet volume in 100-km ultra-marathoners and (ii) to evaluate a possible association between the changes in plasma sodium concentration ([Na+]) and changes in feet volume. Methods In seventy-six 100-km ultra-marathoners, body mass, plasma [Na+], haematocrit and urine specific gravity were determined pre- and post-race. Fluid intake and the changes of volume of the feet were measured where the changes of volume of the feet were estimated using plethysmography. Results Body mass decreased by 1.8 kg (2.4%) (p < 0.0001); plasma [Na+] increased by 1.2% (p < 0.0001). Haematocrit decreased (p = 0.0005). The volume of the feet remained unchanged (p > 0.05). Plasma volume and urine specific gravity increased (p < 0.0001). Fluid intake was positively related to the change in the volume of the feet (r = 0.54, p < 0.0001) and negatively to post-race plasma [Na+] (r = -0.28, p = 0.0142). Running speed was negatively related to both fluid intake (r = -0.33, p = 0.0036) and the change in feet volume (r = -0.23, p = 0.0236). The change in the volume of the feet was negatively related to the change in plasma [Na+] (r = -0.26, p = 0.0227). The change in body mass was negatively related to both post-race plasma [Na+] (r = -0.28, p = 0.0129) and running speed (r = -0.34, p = 0.0028). Conclusions An increase in feet volume after a 100-km ultra-marathon was due to an increased fluid intake. PMID:22472466

  6. Yield of intensified tuberculosis case-finding activities using Xpert(®) MTB/RIF among risk groups in Nepal.

    PubMed

    Khanal, S; Baral, S; Shrestha, P; Puri, M; Kandel, S; Lamichanne, B; Elsey, H; Brouwer, M; Goel, S; Chinnakali, P

    2016-06-21

    Contexte : Vingt-deux districts du Népal où des activités intensifiées de recherche des cas (ICF) de la tuberculose (TB) ont été mises en œuvre au sein de groupes à risque sous l'égide du projet TB REACH en collaboration avec le programme national TB entre juillet 2013 et novembre 2015.Objectifs : Evaluer le rendement du dépistage de la TB grâce à un algorithme basé sur la microscopie de frottis suivie d'un test Xpert(®) MTB/RIF.Schéma : Etude descriptive basée sur des données recueillies en routine.Résultats : Sur un total de 145 679 individus dépistés, 28 574 (19,6%) ont été présumés atteints de TB ; 1239 (4,3%) d'entre eux ont eu une confirmation du diagnostic de TB ; parmi ces derniers, 1195 (96%) ont mis en route un traitement anti-tuberculose. Le rendement a été le plus élevé parmi les personnes vivant avec le virus l'immunodéficience humaine (PVVIH) (6,1%) suivies par les contacts domiciliaires (3,5%) et les habitants des bidonvilles (0,5%). Dans d'autres groupes à risque comme les prisonniers, les travailleurs d'usine, les réfugiés et les diabétiques, le rendement a été inférieur à 0,5%. Le nombre de personnes à dépister (NNS) pour diagnostiquer un cas de TB active a été de 17 pour les PVVIH, de 29 pour les contacts domiciliaires et de 197 pour les habitants des bidonvilles urbains. Sur 11 525 patients émanant soit du programme ICF soit du dépistage de routine, 112 (1%) ont eu un diagnostic de TB multirésistante.Conclusion : Le rendement en termes de cas de TB dépistés parmi les groupes à risque comme les PVVIH et les contacts domiciliaires a été substantiel. Même si ce rendement a été modeste parmi les habitants des bidonvilles, ceux-ci justifient néanmoins une intervention en raison de leur nombre élevé et de leur médiocre accès aux soins.

  7. Countrywide roll-out of Xpert(®) MTB/RIF in Swaziland: the first three years of implementation.

    PubMed

    Sikhondze, W; Dlamini, T; Khumalo, D; Maphalala, G; Dlamini, S; Zikalala, T; Albert, H; Wambugu, J; Tayler-Smith, K; Ali, E; Ade, S; Harries, A D

    2015-06-21

    Contexte : Tous les 19 laboratoires de santé publique du Swaziland qui ont bénéficié de l'installation de machines Xpert(®) MTB/RIF dans le cadre d'un déploiement dans l'ensemble du pays entre juin 2011 et juin 2014.Objectif : Evaluer l'utilisation et la fonctionnalité du text Xpert de 2011 à juin 2014.Schéma : Etude descriptive de la mise en œuvre du test Xpert grâce à des données recueillies en routine.Resultats : Au total, 48 829 tests Xpert ont été réalisés. Parmi eux, 93% l'ont été avec succès dont 14% qui ont détecté Mycobacterium tuberculosis ; parmi ces derniers, 12% étaient résistants à la rifampicine. La cause la plus fréquente de tests non aboutis a été un résultat qualifié d' « Erreur » (62%). Des laboratoires soutenus par le gouvernement et par des partenaires ont obtenu des résultats similaires. L'utilisation annuelle du test Xpert s'est améliorée, passant de 51% de la capacité maximale en 2011 et 2012 à 74% en 2013 et 2014. Un exercice de suivi et évaluation de tous les sites de tests Xpert en 2014 a mis en évidence une performance généralement bonne, puisque plus de 50% des laboratoires atteignaient un score ⩾80% sur la majorité des éléments. Cependant, des scores médiocres ont été obtenus en ce qui concerne l'utilisation des équipements et leur maintenance (6% des sites atteignant un score ⩾80%), l'audit interne (19% atteignant un score ⩾80%) et le contrôle des procédures (25% atteignant un score ⩾80%).Conclusion : Le déploiement national du test Xpert au Swaziland a été un succès, même si certains problèmes opérationnels ont été identifiés et nécessitent d'être résolus.

  8. Rollout of Xpert(®) MTB/RIF in Northwest Cambodia for the diagnosis of tuberculosis among PLHA.

    PubMed

    Auld, S C; Moore, B K; Killam, W P; Eng, B; Nong, K; Pevzner, E C; Eam, K K; Eang, M T; Warren, D; Whitehead, S J

    2014-12-21

    Objectif : Décrire la mise en œuvre et l'utilisation du test Xpert(R) MTB/RIF afin de diagnostiquer la tuberculose (TB) parmi des personnes vivant avec le VIH/SIDA (virus de l'mmunodéficience humaine/syndrome de l'immunodéficience acquise ; PLHA) au Cambodge.Schéma : Après le déploiement du test Xpert, une évaluation a été réalisée dans quatre provinces du Cambodge entre mars et décembre 2012 afin de déterminer l'utilisation, la performance et le délai d'exécution du Xpert parmi les PLHA. Des données ont été recueillies à partir des dossiers papiers des patients.Résultats : Sur 497 PLHA ayant une grille de symptômes de TB positive, 357 (72%) ont bénéficié d'une microscopie de frottis et 250 (50%) ont eu un test Xpert ; 25 (10%) PLHA testés par Xpert étaient positifs pour la TB et aucun n'était résistant à la rifampicine. L'utilisation du Xpert est passée de 23% à 75% avec un délai d'exécution médian d'un jour. Dans les districts, l'utilisation allait de zéro à 85% et le délai de mise en œuvre allait de zéro à 22 jours.Conclusion : Si les données précoces montrent une utilisation croissante du Xpert chez les PLHA avec une grille de symptômes positive, la majorité des patients bénéficiait initialement d'un diagnostic par examen microscopique de frottis. Les délais de formation et les problèmes posés par l'envoi des spécimens peuvent avoir contribué à la variabilité du recours au Xpert et au délai de sa mise en œuvre, particulièrement dans les endroits dépourvus de possibilité de test Xpert sur place. Davantage de soutien aux programmes, notamment en termes d'envoi des spécimens et de retour des résultats, pourrait faciliter son utilisation appropriée.

  9. Diagnosis and treatment of TB patients with rifampicin resistance detected using Xpert(®) MTB/RIF in Zimbabwe.

    PubMed

    Charambira, K; Ade, S; Harries, A D; Ncube, R T; Zishiri, C; Sandy, C; Mutunzi, H; Takarinda, K; Owiti, P; Mafaune, P; Chonzi, P

    2016-06-21

    Contexte : Au Zimbabwe, la prise en charge des patients tuberculeux ayant une résistance à la rifampicine (RMP) diagnostiqués par Xpert(®) MTB/RIF est préoccupante.Objectif : Evaluer les liens entre le diagnostic et le traitement de ces patients dans les provinces de Harare et de Manicaland en 2014.Schéma : Etude rétrospective de cohorte.Résultats : Sur 20 329 tests Xpert, 90% ont été réussis, 11% ont détecté Mycobacterium tuberculosis et 4,5% ont mis en évidence une résistance à la RMP. Il y a eu 77 patients atteints d'une tuberculose (TB) résistante à la RMP diagnostiqués par Xpert. Parmi eux, 70% ont bénéficié d'un envoi d'échantillon au laboratoire de référence pour une culture et un test de pharmacosensibilité (CDST) ; pour 53% d'entre eux, les échantillons sont arrivés à bon port ; pour 21%, les échantillons ont mis en évidence une croissance de M. tuberculosis ; et chez 17%, les résultats du CDST ont été enregistrés et tous ont confirmé la résistance à la RMP. Sur 77 patients, 34 (44%) n'ont jamais mis en route un traitement pour le TB multirésistante (TB-MDR) ; les motifs documentés étaient le décès, la perte de vue ou un traitement incorrect. Des 43 patients qui ont débuté le traitement de TB-MDR, 12 (71%) à Harare et 17 (65%) au Manicaland ont commencé dans les 2 semaines suivant le diagnostic.Conclusion : L'Xpert a été lancé avec succès dans deux provinces du Zimbabwe. Cependant, le processus de confirmation du CDST pour une TB résistante à la RMP diagnostiquée par Xpert ne fonctionne pas bien, et de nombreux patients sont soit traités avec retard, soit ne démarrent jamais le traitement de TB-MDR. Ces problèmes doivent être examinés par le programme.

  10. Performance of the new automated Abbott RealTime MTB assay for rapid detection of Mycobacterium tuberculosis complex in respiratory specimens.

    PubMed

    Chen, J H K; She, K K K; Kwong, T-C; Wong, O-Y; Siu, G K H; Leung, C-C; Chang, K-C; Tam, C-M; Ho, P-L; Cheng, V C C; Yuen, K-Y; Yam, W-C

    2015-09-01

    The automated high-throughput Abbott RealTime MTB real-time PCR assay has been recently launched for Mycobacterium tuberculosis complex (MTBC) clinical diagnosis. This study would like to evaluate its performance. We first compared its diagnostic performance with the Roche Cobas TaqMan MTB assay on 214 clinical respiratory specimens. Prospective analysis of a total 520 specimens was then performed to further evaluate the Abbott assay. The Abbott assay showed a lower limit of detection at 22.5 AFB/ml, which was more sensitive than the Cobas assay (167.5 AFB/ml). The two assays demonstrated a significant difference in diagnostic performance (McNemar's test; P = 0.0034), in which the Abbott assay presented significantly higher area under curve (AUC) than the Cobas assay (1.000 vs 0.880; P = 0.0002). The Abbott assay demonstrated extremely low PCR inhibition on clinical respiratory specimens. The automated Abbott assay required only very short manual handling time (0.5 h), which could help to improve the laboratory management. In the prospective analysis, the overall estimates for sensitivity and specificity of the Abbott assay were both 100 % among smear-positive specimens, whereas the smear-negative specimens were 96.7 and 96.1 %, respectively. No cross-reactivity with non-tuberculosis mycobacterial species was observed. The superiority in sensitivity of the Abbott assay for detecting MTBC in smear-negative specimens could further minimize the risk in MTBC false-negative detection. The new Abbott RealTime MTB assay has good diagnostic performance which can be a useful diagnostic tool for rapid MTBC detection in clinical laboratories.

  11. Detecting Outliers in Marathon Data by Means of the Andrews Plot

    NASA Astrophysics Data System (ADS)

    Stehlík, Milan; Wald, Helmut; Bielik, Viktor; Petrovič, Juraj

    2011-09-01

    For an optimal race performance, it is important, that the runner keeps steady pace during most of the time of the competition. First time runners or athletes without many competitions often experience an "blow out" after a few kilometers of the race. This could happen, because of strong emotional experiences or low control of running intensity. Competition pace of half marathon of the middle level recreational athletes is approximately 10 sec quicker than their training pace. If an athlete runs the first third of race (7 km) at a pace that is 20 sec quicker than is his capacity (trainability), he would experience an "blow out" in the last third of the race. This would be reflected by reducing the running intensity and inability to keep steady pace in the last kilometers of the race and in the final time as well. In sports science, there are many diagnostic methods ([3], [2], [6]) that are used for prediction of optimal race pace tempo and final time. Otherwise there is lacking practical evidence of diagnostics methods and its use in the field (competition, race). One of the conditions that needs to be carried out is that athletes have not only similar final times, but it is important that they keep constant pace as much as possible during whole race. For this reason it is very important to find outliers. Our experimental group consisted of 20 recreational trained athletes (mean age 32,6 years±8,9). Before the race the athletes were instructed to run on the basis of their subjective feeling and previous experience. The data (running pace of each kilometer, average and maximal heart rate of each kilometer) were collected by GPS-enabled personal trainer Forerunner 305.

  12. Preparation for and physiological responses to competing in the Marathon des Sables: a case report.

    PubMed

    Williams, N; Wickes, S J; Gilmour, K; Barker, N; Scott, J P R

    2014-02-01

    A case study into the preparation and physiological responses of competing in the Marathon des Sables (MDS) was conducted by preparing a male competitor for, and monitoring him during, his first attempt at the race. The aims of this case report were to (a) prepare and monitor an ex-Olympic, male rower (S1) during the 2010 race and; (b) compare his physiological responses and race performance to that of the current MDS record holder (S2). S1 (age 37 y; body mass 94.0 kg; height 1.92 m; VO(2peak) 66.0 ml·kg⁻¹·min⁻¹) and S2 (age 37 y; body mass 60.8 kg; height 1.68 m; VO(2peak) 65.9 ml·kg⁻¹·min⁻¹) completed a heat test and S1 subsequently underwent 7 d of heat acclimation prior to the MDS. Gastro-intestinal temperature (Tgi) and heart rate (HR) were measured for S1 during Stages 2, 4, and 5 of the MDS and pre- and post-stage body mass, and urine specific gravity were measured for all stages. Race time and average speeds were collected for S1 and S2. Total race times for S1 and S2 were 25:29:35 and 19:45:08 h:min:s. S1's mean (± 1 SD) percentage HR range (%HRR=[HR-HRmin]/[HRmax-HRmin]x100) was 66.1 ± 13.4% and Tgi ranged between 36.63-39.65°C. The results provide a case report on the physiological responses of a highly aerobically-trained, but novice ultra-endurance runner competing in the MDS, and allow for a comparison with an elite performer. PMID:24445543

  13. Decreased hypothalamic gonadotropin-releasing hormone secretion in male marathon runners.

    PubMed

    MacConnie, S E; Barkan, A; Lampman, R M; Schork, M A; Beitins, I Z

    1986-08-14

    Hypogonadotropic hypogonadism due to a deficiency in hypothalamic gonadotropin-releasing hormone is common in female athletes ("hypothalamic amenorrhea"). It is not known, however, whether a similar phenomenon occurs in male athletes. We investigated the integrity of the hypothalamic-pituitary-gonadal axis in six highly trained male marathon runners (who were running 125 to 200 km per week). The mean (+/- SEM) frequency of spontaneous luteinizing hormone pulses was diminished in the runners, as compared with healthy controls (2.2 +/- 0.48 vs. 3.6 +/- 0.24 pulses per eight hours, P less than 0.05). The amplitude of the pulses was also low in the runners (0.9 +/- 0.24 vs. 1.6 +/- 0.15 mlU per milliliter; P less than 0.05), and the responses of luteinizing hormone to gradually increasing doses of exogenous gonadotropin-releasing hormone were decreased. Plasma testosterone levels were similar in the two groups and increased equally in response to an intramuscular injection of 2000 units of human chorionic gonadotropin. During short-term intense physical exercise (a treadmill run at 72 percent of maximal oxygen consumption for two hours), the plasma gonadotropin levels in the athletes remained stable, but significant elevations in plasma levels of cortisol, prolactin, and testosterone occurred. We conclude that highly trained male athletes, like their female counterparts, may have a deficiency of hypothalamic gonadotropin-releasing hormone. This condition may be caused by the prolonged, repetitive elevations of gonadal steroids and other hormones known to suppress gonadotropin-releasing hormone secretion that are elicited by their daily exercise.

  14. Media's role in broadcasting acute stress following the Boston Marathon bombings.

    PubMed

    Holman, E Alison; Garfin, Dana Rose; Silver, Roxane Cohen

    2014-01-01

    We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), -2.36, 3.23], but lower nationwide when compared with Boston (b = -2.21; SE = 1.07; 95% CI, -4.31, -0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn't. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities.

  15. Hydration assessment among marathoners using urine specific gravity and bioelectrical impedance analysis.

    PubMed

    Cutrufello, Paul T; Dixon, Curt B; Zavorsky, Gerald S

    2016-01-01

    The present study examined the relationship between urine specific gravity (Usg), body mass (BM) and bioelectrical impedance determined variables [total body water (TBW), per cent TBW and impedance values] before and after a marathon (n = 25 men; 10 women). A significant reduction in BM (pre: 71.2 ± 12.4 kg; post: 69.6 ± 12.0 kg; p < 0.001) and an increase in Usg (pre: 1.009 ± 0.007; post: 1.018 ± 0.009; p < 0.001) was observed post-race. TBW was not significantly decreased (pre: 42.7 ± 8.0 kg; post: 42.4 ± 7.7 kg) while per cent TBW significantly increased post-race (pre: 60.0 ± 3.9%; post: 60.8 ± 3.8%; p < 0.001). Impedance values were significantly greater post-race (pre: 3288 ± 482; post: 3416 ± 492 Ω; p < 0.001). There was no correlation between the change in Usg and the change in BM or any of the bioelectrical impedance determined variables. On average, BM, Usg and impedance values appear to express changes in hydration; however, the observed changes among these variables for a given individual appear to be inconsistent with one another. PMID:27373703

  16. Hydration assessment among marathoners using urine specific gravity and bioelectrical impedance analysis.

    PubMed

    Cutrufello, Paul T; Dixon, Curt B; Zavorsky, Gerald S

    2016-01-01

    The present study examined the relationship between urine specific gravity (Usg), body mass (BM) and bioelectrical impedance determined variables [total body water (TBW), per cent TBW and impedance values] before and after a marathon (n = 25 men; 10 women). A significant reduction in BM (pre: 71.2 ± 12.4 kg; post: 69.6 ± 12.0 kg; p < 0.001) and an increase in Usg (pre: 1.009 ± 0.007; post: 1.018 ± 0.009; p < 0.001) was observed post-race. TBW was not significantly decreased (pre: 42.7 ± 8.0 kg; post: 42.4 ± 7.7 kg) while per cent TBW significantly increased post-race (pre: 60.0 ± 3.9%; post: 60.8 ± 3.8%; p < 0.001). Impedance values were significantly greater post-race (pre: 3288 ± 482; post: 3416 ± 492 Ω; p < 0.001). There was no correlation between the change in Usg and the change in BM or any of the bioelectrical impedance determined variables. On average, BM, Usg and impedance values appear to express changes in hydration; however, the observed changes among these variables for a given individual appear to be inconsistent with one another.

  17. Media’s role in broadcasting acute stress following the Boston Marathon bombings

    PubMed Central

    Holman, E. Alison; Garfin, Dana Rose; Silver, Roxane Cohen

    2014-01-01

    We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), −2.36, 3.23], but lower nationwide when compared with Boston (b = −2.21; SE = 1.07; 95% CI, −4.31, −0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn't. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities. PMID:24324161

  18. Media's role in broadcasting acute stress following the Boston Marathon bombings.

    PubMed

    Holman, E Alison; Garfin, Dana Rose; Silver, Roxane Cohen

    2014-01-01

    We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), -2.36, 3.23], but lower nationwide when compared with Boston (b = -2.21; SE = 1.07; 95% CI, -4.31, -0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn't. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities. PMID:24324161

  19. Marathon Running, Accreditation of Study Programmes and Professional Development in Consultancies: Are They All about the Same? A Cognitive Perspective on Transfer of Training

    ERIC Educational Resources Information Center

    Gruber, Hans

    2013-01-01

    Three challenges are presented which address problems of transfer of training: running marathon, accreditation of study programmes, professional development in consultancies. It is discussed in-how-far and why different approaches to transfer of training stress commonalities or differences between these challenges. The results are used to analyse…

  20. The effects of prolonged running on foot posture: a repeated measures study of half marathon runners using the foot posture index and navicular height

    PubMed Central

    2013-01-01

    Background Different foot postures are associated with alterations in foot function, kinetics and the subsequent occurrence of injury. Little is known about changes in foot posture following prolonged weightbearing exercise. This study aimed to identify changes in foot posture after running a half marathon. Methods Foot posture was measured using the Foot Posture Index (FPI-6) and navicular height in thirty volunteer participants before and after running a half marathon. FPI-6 scores were converted to Rasch logit values and means compared for these and navicular height using an ANOVA. Results There was a 5 mm drop in navicular height in both feet when measured after the half marathon (P < 0.05). The FPI-6 showed a side x time interaction with an increase in score indicating a more ‘pronated’ position in the left foot of + 2 [Rasch value + 1.7] but no change in the right foot (+ 0.4 [+ 0.76]) following the half marathon. Conclusion The apparent differences between the FPI-6 and navicular height on the right foot may be because the FPI-6 takes soft tissue contour changes into consideration whilst the navicular height focuses on skeletal changes. The changes in foot posture towards a more pronated position may have implications for foot function, and therefore risk of injury; shoe fit and comfort and also the effect of therapeutic orthoses worn during prolonged running. PMID:23705863