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1

Implementation of open and closed kinetic chain quadriceps strengthening exercises after anterior cruciate ligament reconstruction.  

PubMed

When working with athletes that have recently undergone anterior cruciate ligament (ACL) reconstructive surgery, a common goal of athletic trainers, strength and conditioning coaches, physicians, and physical therapists is to restore quadriceps strength while protecting the reconstructed ACL and patellofemoral joint from unnecessary stresses. Quadriceps strengthening exercises are often referred to as occurring in the open kinetic chain (OKC) or closed kinetic chain (CKC). Currently, there is little agreement in the literature as to whether only CKC exercises or a combination of OKC and CKC exercise should be performed after ACL reconstruction to strengthen the quadriceps. We believe that a combination of OKC and CKC exercises can be used to effectively and safely strengthen the quadriceps after ACL reconstruction. The purposes of this review are to examine the scientific literature currently available for the effects of OKC and CKC exercise on ACL strain and patellofemoral joint stress, and to present a sound rationale for using a combination of OKC and CKC exercises for quadriceps strengthening after ACL reconstruction. On the basis of our review, both OKC and CKC exercises can be modified and implemented for quadriceps strengthening after ACL reconstruction without causing excessive ACL strain or patellofemoral joint stress. PMID:11726258

Ross, M D; Denegar, C R; Winzenried, J A

2001-11-01

2

Comparison of neuromuscular and quadriceps strengthening exercise in the treatment of varus malaligned knees with medial knee osteoarthritis: a randomised controlled trial protocol  

PubMed Central

Background Osteoarthritis of the knee involving predominantly the medial tibiofemoral compartment is common in older people, giving rise to pain and loss of function. Many people experience progressive worsening of the disease over time, particularly those with varus malalignment and increased medial knee joint load. Therefore, interventions that can reduce excessive medial knee loading may be beneficial in reducing the risk of structural progression. Traditional quadriceps strengthening can improve pain and function in people with knee osteoarthritis but does not appear to reduce medial knee load. A neuromuscular exercise program, emphasising optimal alignment of the trunk and lower limb joints relative to one another, as well as quality of movement performance, while dynamically and functionally strengthening the lower limb muscles, may be able to reduce medial knee load. Such a program may also be superior to traditional quadriceps strengthening with respect to improved pain and physical function because of the functional and dynamic nature. This randomised controlled trial will investigate the effect of a neuromuscular exercise program on medial knee joint loading, pain and function in individuals with medial knee joint osteoarthritis. We hypothesise that the neuromuscular program will reduce medial knee load as well as pain and functional limitations to a greater extent than a traditional quadriceps strengthening program. Methods/Design 100 people with medial knee pain, radiographic medial compartment osteoarthritis and varus malalignment will be recruited and randomly allocated to one of two 12-week exercise programs: quadriceps strengthening or neuromuscular exercise. Each program will involve 14 supervised exercise sessions with a physiotherapist plus four unsupervised sessions per week at home. The primary outcomes are medial knee load during walking (the peak external knee adduction moment from 3D gait analysis), pain, and self-reported physical function measured at baseline and immediately following the program. Secondary outcomes include the external knee adduction moment angular impulse, electromyographic muscle activation patterns, knee and hip muscle strength, balance, functional ability, and quality-of-life. Discussion The findings will help determine whether neuromuscular exercise is superior to traditional quadriceps strengthening regarding effects on knee load, pain and physical function in people with medial knee osteoarthritis and varus malalignment. Trial Registration Australian New Zealand Clinical Trials Registry reference: ACTRN12610000660088 PMID:22141334

2011-01-01

3

Effects of dietary intervention and quadriceps strengthening exercises on pain and function in overweight people with knee pain: randomised controlled trial  

PubMed Central

Objective To determine whether dietary intervention or knee strengthening exercise, or both, can reduce knee pain and improve knee function in overweight and obese adults in the community. Design Pragmatic factorial randomised controlled trial. Setting Five general practices in Nottingham. Participants 389 men and women aged 45 and over with a body mass index (BMI) of ?28.0 and self reported knee pain. Interventions Participants were randomised to dietary intervention plus quadriceps strengthening exercises; dietary intervention alone; quadriceps strengthening exercises alone; advice leaflet only (control group). Dietary intervention consisted of individualised healthy eating advice that would reduce normal intake by 2.5 MJ (600 kcal) a day. Interventions were delivered at home visits over a two year period. Main outcome measures The primary outcome was severity of knee pain scored with the Western Ontario McMaster (WOMAC) osteoarthritis index at 6, 12, and 24 months. Secondary outcomes (all at 24 months) included WOMAC knee physical function and stiffness scores and selected domains on the SF-36 and the hospital anxiety and depression index. Results 289 (74%) participants completed the trial. There was a significant reduction in knee pain in the knee exercise groups compared with those in the non-exercise groups at 24 months (percentage risk difference 11.61, 95% confidence interval 1.81% to 21.41%). The absolute effect size (0.25) was moderate. The number needed to treat to benefit from a ?30% improvement in knee pain at 24 months was 9 (5 to 55). In those randomised to knee exercise improvement in function was evident at 24 months (mean difference ?3.64, ?6.01 to ?1.27). The mean difference in weight loss at 24 months in the dietary intervention group compared with no dietary intervention was 2.95 kg (1.44 to 4.46); for exercise versus no exercise the difference was 0.43 kg (?0.82 to 1.68). This difference in weight loss was not associated with improvement in knee pain or function but was associated with a reduction in depression (absolute effect size 0.19). Conclusions A home based, self managed programme of simple knee strengthening exercises over a two year period can significantly reduce knee pain and improve knee function in overweight and obese people with knee pain. A moderate sustained weight loss is achievable with dietary intervention and is associated with reduced depression but is without apparent influence on pain or function. Trial registration Current Controlled Trials ISRCTN 93206785. PMID:19690345

2009-01-01

4

Closed kinetic chain alone compared to combined open and closed kinetic chain exercises for quadriceps strengthening after anterior cruciate ligament reconstruction with respect to return to sports: a prospective matched follow-up study.  

PubMed

Rehabilitation after anterior cruciate ligament (ACL) reconstruction has focused over the past decade on closed kinetic chain (CKC) exercises due to presumably less strain on the graft than with isokinetic open kinetic chain exercises (OKC); however, recent reports suggest that there are only minor differences in ACL strain values between some CKC and OKC exercises. We studied anterior knee laxity, thigh muscle torque, and return to preinjury sports level in 44 patients with unilateral ACL; group 1 carried out quadriceps strengthening only with CKC while group 2 trained with CKC plus OKC exercises starting from week 6 after surgery. Anterior knee laxity was determined with a KT-1000 arthrometer; isokinetic concentric and eccentric quadriceps and hamstring muscle torque were studied with a Kin-Com dynamometer before and 6 months after surgery. At an average of 31 months after surgery the patients answered a questionnaire regarding their current knee function and physical activity/sports to determine the extent and timing of their recovery. No significant differences in anterior knee laxity were noted between the groups 6 months postsurgery. Patients in group 2 increased their quadriceps torque significantly more than those in group 1, but no differences were found in hamstring torque between the groups. A significantly higher number of patients in group 2 (n = 12) than in group 1 (n = 5) returned to sports at the same level as before the injury (P < 0.05). Patients from group 2 who returned to sports at the same level did so 2 months earlier than those in group 1. Thus the addition of OKC quadriceps training after ACL reconstruction results in a significantly better improvement in quadriceps torque without reducing knee joint stability at 6 months and also leads to a significantly higher number of athletes returning to their previous activity earlier and at the same level as before injury. PMID:11147151

Mikkelsen, C; Werner, S; Eriksson, E

2000-01-01

5

Comparative Study of Hamstring and Quadriceps Strengthening Treatments in the Management of Knee Osteoarthritis  

PubMed Central

[Purpose] Osteoarthritis (OA) of the knee is the most common form of joint disease. It is one of the major causes of impaired function that reduces quality of life (QOL) worldwide. The purpose of this study was to compare exercise treatments for hamstring and quadriceps strength in the management of knee osteoarthritis. [Subjects and Methods] Forty patients with OA knee, aged 50–65 years were divided into 2 groups. The first group (57.65±4.78 years) received hot packs and performed strengthening exercises for the quadriceps and hamstring, and stretching exercises for the hamstring. The second group (58.15±5.11 years) received hot packs and performed strengthening exercises for only the quadriceps, and stretching exercise for the hamstring. Outcome measures were the WOMAC (Western Ontario and McMaster Universities OA index questionnaire), Visual Analogue Scale (VAS) assessment of pain, the Fifty-Foot Walk Test (FWS), and Handheld dynamometry. [Results] There was a significant difference between the groups. The first group showed a more significant result than the second group. [Conclusion] Strengthening of the hamstrings in addition to strengthening of the quadriceps was shown to be beneficial for improving subjective knee pain, range of motion and decreasing the limitation of functional performance of patients with knee osteoarthritis. PMID:25013274

Al-Johani, Ahmed H; Kachanathu, Shaji John; Ramadan Hafez, Ashraf; Al-Ahaideb, Abdulaziz; Algarni, Abdulrahman D; Meshari Alroumi, Abdulmohsen; Alenazi, Aqeel M.

2014-01-01

6

Reduced Quadriceps Activation After Lumbar Paraspinal Fatiguing Exercise  

PubMed Central

Context: Although poor paraspinal muscle endurance has been associated with less quadriceps activation (QA) in persons with a history of low back pain, no authors have addressed the acute neuromuscular response after lumbar paraspinal fatiguing exercise. Objective: To compare QA after lumbar paraspinal fatiguing exercise in healthy individuals and those with a history of low back pain. Design: A 2 × 4 repeated-measures, time-series design. Setting: Exercise and Sport Injury Laboratory. Patients or Other Participants: Sixteen volunteers participated (9 males, 7 females; 8 controls and 8 with a history of low back pain; age = 24.1 ± 3.1 years, height = 173.4 ± 7.1 cm, mass = 72.4 ± 12.1 kg). Intervention(s): Subjects performed 3 sets of isometric lumbar paraspinal fatiguing muscle contractions. Exercise sets continued until the desired shift in lumbar paraspinal electromyographic median power frequency was observed. Baseline QA was compared with QA after each exercise set. Main Outcome Measure(s): An electric burst was superimposed while subjects performed a maximal quadriceps contraction. We used the central activation ratio to calculate QA = (FMVIC/[FMVIC + FBurst])* 100, where F = force and MVIC = maximal voluntary isometric contractions. Quadriceps electromyographic activity was collected at the same time as QA measurements to permit calculation of median frequency during MVIC. Results: Average QA decreased from baseline (87.4% ± 8.2%) after the first (84.5% ± 10.5%), second (81.4% ± 11.0%), and third (78.2% ± 12.7%) fatiguing exercise sets. On average, the group with a history of low back pain showed significantly more QA than controls. No significant change in quadriceps median frequency was noted during the quadriceps MVICs. Conclusions: The quadriceps muscle group was inhibited after lumbar paraspinal fatiguing exercise in the absence of quadriceps fatigue. This effect may be different for people with a history of low back pain compared with healthy controls. PMID:16619099

Hart, Joseph M; Fritz, Julie M; Kerrigan, D. Casey; Saliba, Ethan N; Gansneder, Bruce M; Ingersoll, Christopher D

2006-01-01

7

The Effect of Baseline Quadriceps Activation on Changes in Quadriceps Strength After Exercise Therapy in Subjects with Knee Osteoarthritis  

PubMed Central

Objective The aim of this study was to examine whether pretreatment magnitude of quadriceps activation (QA) helps predict changes in quadriceps strength after exercise therapy in subjects with knee osteoarthritis (OA). We hypothesized that subjects with lower magnitudes of QA (greater failure of muscle activation) would have smaller gains in strength compared to those with higher magnitudes of QA following exercise therapy. Methods 111 subjects with knee OA (70 ?) participated in the study. Baseline measures included demographic information, quadriceps muscle strength and QA using a burst-superimposition isometric torque test. Following baseline testing, subjects underwent a 6 week supervised exercise program designed to improve strength, range of motion, balance and agility, and physical function. On completion of the exercise program, quadriceps strength and QA were re-assessed. Multiple regression analysis was used to determine whether baseline QA predicted quadriceps strength scores at the 2 month follow-up period. Results Bivariate correlations demonstrated that baseline QA was significantly associated with quadriceps strength at baseline (rho = 0.30, p < 0.01) and 2 month follow-up (rho = 0.23, p = 0.01). Greater magnitude of baseline QA correlated to higher strength. While controlling for baseline quadriceps strength and type of exercise therapy, the level of QA did not predict quadriceps strength at the 2 month follow-up (? = ?0.04, p = 0.18). Conclusions Baseline QA did not predict changes in quadriceps strength following exercise therapy. Measurement of QA using the CAR method does not appear to be helpful in identifying subjects with knee OA who will have difficulty improving quadriceps strength with exercise therapy. Investigation of other factors that may affect response to exercise therapy is warranted. PMID:19565548

Scopaz, Kristen A.; Piva, Sara R.; Gil, Alexandra B.; Woollard, Jason D.; Oddis, Chester V.; Fitzgerald, G. Kelley

2009-01-01

8

Quadriceps and Hamstrings Coactivation During Common Therapeutic Exercises  

PubMed Central

Context Anterior tibial shear force and knee valgus moment increase anterior cruciate ligament (ACL) loading. Muscle coactivation of the quadriceps and hamstrings influences anterior tibial shear force and knee valgus moment, thus potentially influencing ACL loading and injury risk. Therefore, identifying exercises that facilitate balanced activation of the quadriceps and hamstrings might be beneficial in ACL injury rehabilitation and prevention. Objective To quantify and compare quadriceps with hamstrings coactivation electromyographic (EMG) ratios during commonly used closed kinetic chain exercises. Design Cross-sectional study. Setting Research laboratory. Patients or Other Participants Twenty-seven healthy, physically active volunteers (12 men, 15 women; age = 22.1 ± 3.1 years, height = 171.4 ± 10 cm, mass = 72.4 ± 16.7 kg). Intervention(s) Participants completed 9 separate closed chain therapeutic exercises in a randomized order. Main Outcome Measure(s) Surface electromyography quantified the activity level of the vastus medialis (VM), vastus lateralis (VL), medial hamstrings (MH), and biceps femoris (BF) muscles. The quadriceps-to-hamstrings (Q:H) coactivation ratio was computed as the sum of average quadriceps (VM, VL) EMG amplitude divided by the sum of average hamstrings (MH, BF) EMG amplitude for each trial. We used repeated-measures analyses of variance to compare Q:H ratios and individual muscle contributions across exercises (? = .05), then used post hoc Tukey analyses. Results We observed a main effect for exercise (F3,79 = 22.6, P < .001). The post hoc Tukey analyses revealed smaller Q:H ratios during the single-limb dead lift (2.87 ± 1.77) than the single-limb squat (5.52 ± 2.89) exercise. The largest Q:H ratios were observed during the transverse-lunge (7.78 ± 5.51, P < .001), lateral-lunge (9.30 ± 5.53, P < .001), and forward-lunge (9.70 ± 5.90, P < .001) exercises. Conclusions The most balanced (smallest) coactivation ratios were observed during the single-limb dead-lift, lateral-hop, transverse-hop, and lateral band-walk exercises. These exercises potentially could facilitate balanced activation in ACL rehabilitation and injury-prevention programs. They also could be used in postinjury rehabilitation programs in a safe and progressive manner. PMID:22889655

Begalle, Rebecca L.; DiStefano, Lindsay J.; Blackburn, Troy; Padua, Darin A.

2012-01-01

9

Effect of quadriceps exercise on synostosis following tibial osteotomy with internal fixation: a finite element simulation  

Microsoft Academic Search

Objective. To clarify the influence of quadriceps muscle exercises on the apposed bony surfaces of the tibia after a high tibial osteotomy. The sl:udy was designed so that the instability at the osteotomy could be evaluated by a finite element simulation.Background. A detailed knowledge of the effects of quadriceps exercises on the healing tibia may lead to a solid rationale

Haruhiko Sato; Shin Morishita

1999-01-01

10

Quadriceps Inhibition After Repetitive Lumbar Extension Exercise in Persons With a History of Low Back Pain  

PubMed Central

Context: A neuromuscular relationship exists between the lumbar extensor and quadriceps muscles during fatiguing exercise. However, this relationship may be different for persons with low back pain (LBP). Objective: To compare quadriceps inhibition after isometric, fatiguing lumbar extension exercise between persons with a history of LBP and control subjects. Design: A 2 × 3 factorial, repeated-measures, time-series design with independent variables of group (persons with a history of LBP, controls) and time (baseline, postexercise set 1, postexercise set 2). Setting: University research laboratory. Patients or Other Participants: Twenty-five subjects with a history of LBP were matched by sex, height, and mass to 25 healthy control subjects. Intervention(s): Electromyography median frequency indexed lumbar paraspinal muscular fatigue while subjects performed 2 sets of isometric lumbar extension exercise. Subjects exercised until a 15% downward shift in median frequency for the first set and a 25% shift for the second set were demonstrated. Main Outcome Measure(s): Knee extension force was measured while subjects performed an isometric maximal quadriceps contraction. During this maximal effort, a percutaneous electric stimulus was applied to the quadriceps, causing a transient, supramaximal increase in force output. We used the ratio between the 2 forces to estimate quadriceps inhibition. Quadriceps electromyographic activity was recorded during the maximal contractions to compare median frequencies over time. Results: Both groups exhibited significantly increased quadriceps inhibition after the first (12.6% ± 10.0%, P < .001) and second (15.2% ± 9.7%, P < .001) exercise sets compared with baseline (9.6% ± 9.3%). However, quadriceps inhibition was not different between groups. Conclusions: Persons with a history of LBP do not appear to be any more or less vulnerable to quadriceps inhibition after fatiguing lumbar extension exercise. PMID:17043693

Hart, Joseph M; Fritz, Julie M; Kerrigan, D. Casey; Saliba, Ethan N; Gansneder, Bruce M; Ingersoll, Christopher D

2006-01-01

11

Closed kinetic chain alone compared to combined open and closed kinetic chain exercises for quadriceps strengthening after anterior cruciate ligament reconstruction with respect to return to sports: a prospective matched follow-up study  

Microsoft Academic Search

Rehabilitation after anterior cruciate ligament (ACL) reconstruction has focused over the past decade on closed kinetic chain (CKC) exercises due to presumably less strain on the graft than with isokinetic open kinetic chain exercises (OKC); however, recent reports suggest that there are only minor differences in ACL strain values between some CKC and OKC exercises. We studied anterior knee laxity,

C. Mikkelsen; S. Werner; E. Eriksson

2000-01-01

12

ISOKINETIC ECCENTRIC EXERCISE OF QUADRICEPS FEMORIS DOES NOT AFFECT RUNNING ECONOMY  

Microsoft Academic Search

Vassilis, P, Vassilios, B, Vassilis, M, Athanasios, JZ, Vassilis, T, Christina, K, and Yiannis, K. Isokinetic eccentric exercise of quadriceps femoris does not affect running economy. JS trength Cond Res 22: 1222-1227, 2008—The purpose of this study was to investigate whether running economy is affected by isokinetic eccentric exercise designed to cause muscle damage. Twenty- four young healthy men performed

PASCHALIS VASSILIS; BALTZOPOULOS VASSILIOS; MOUGIOS VASSILIS; JAMURTAS Z. ATHANASIOS; THEOHARIS VASSILIS; KARATZAFERI CHRISTINA; KOUTEDAKIS YIANNIS

13

The Effects of Quadriceps Strength Following Static and Dynamic Whole Body Vibration Exercise.  

PubMed

Numerous studies have shown performance benefits from including whole-body vibration (WBV) whether as a training modality or an acute exercise protocol when utilized as a component of the resistance training program. Some studies have indicated that performing dynamic exercises as compared to static position exercises while exposed to WBV might be beneficial, however, evidence is lacking. Thus, the purpose of this study was to determine if an acute bout of dynamic vs. static squats performed during WBV results in increases in quadriceps force production via dynamic isokinetic knee extension and flexion exercise. PMID:25268289

Bush, Jill A; Blog, Gabriel L; Kang, Jie; Faigenbaum, Avery D; Ratamess, Nicholas A

2014-09-29

14

Effect of Isometric Quadriceps Exercise on Muscle Strength, Pain, and Function in Patients with Knee Osteoarthritis: A Randomized Controlled Study  

PubMed Central

[Purpose] The aim of present study was to investigate the effects of isometric quadriceps exercise on muscle strength, pain, and function in knee osteoarthritis. [Subjects and Methods] Outpatients (N=42, 21 per group; age range 40–65 years; 13 men and 29 women) with osteoarthritis of the knee participated in the study. The experimental group performed isometric exercises including isometric quadriceps, straight leg raising, and isometric hip adduction exercise 5 days a week for 5 weeks, whereas the control group did not performed any exercise program. The outcome measures or dependent variables selected for this study were pain intensity, isometric quadriceps strength, and knee function. These variables were measured using the Numerical Rating Scale (NRS), strength gauge device, and reduced WOMAC index, respectively. All the measurements were taken at baseline (week 0) and at the end of the trial at week 5. [Results] In between-group comparisons, the maximum isometric quadriceps strength, reduction in pain intensity, and improvement in function in the isometric exercise group at the end of the 5th week were significantly greater than those of the control group (p<0.05). [Conclusion] The 5-week isometric quadriceps exercise program showed beneficial effects on quadriceps muscle strength, pain, and functional disability in patients with osteoarthritis of the knee. PMID:24926143

Anwer, Shahnawaz; Alghadir, Ahmad

2014-01-01

15

Quadriceps Function After Exercise in Patients with Anterior Cruciate Ligament–Reconstructed Knees Wearing Knee Braces  

PubMed Central

Context: Knee braces and neoprene sleeves are commonly worn by people with anterior cruciate ligament reconstructions (ACLRs) during athletic activity. How knee braces and sleeves affect muscle activation in people with ACLRs is unclear. Purpose: To determine the effects of knee braces and neoprene knee sleeves on the quadriceps central activation ratio (CAR) before and after aerobic exercise in people with ACLRs. Design: Crossover study. Patients or Other Participants: Fourteen people with a history of ACLR (9 women, 5 men: age = 23.61 ± 4.44 years, height = 174.09 ± 9.82 cm, mass = 75.35 ± 17.48 kg, months since ACLR = 40.62 ± 20.41). Intervention(s): During each of 3 sessions, participants performed a standardized aerobic exercise protocol on a treadmill. The independent variables were condition (brace, sleeve, or control) and time (baseline, pre-exercise with brace, postexercise with brace, postexercise without brace). Main Outcome Measure(s): Normalized torque measured during a maximal voluntary isometric contraction (TMVIC) and CAR were measured by a blinded assessor using the superimposed burst technique. The CAR was expressed as a percentage of full muscle activation. The quadriceps CAR and TMVIC were measured 4 times during each session: baseline, pre-exercise with brace, postexercise with brace, and postexercise without brace. Results: Immediately after the application of the knee brace, TMVIC decreased (P = .01), but no differences between bracing conditions were observed. We noted reduced TMVIC and CAR (P < .001) after exercise, both with and without the brace. No differences were seen between bracing conditions after aerobic exercise. Conclusions: The decrease in TMVIC immediately after brace application was not accompanied by differences between bracing conditions. Wearing a knee brace or neoprene sleeve did not seem to affect the deterioration of quadriceps function after aerobic exercise. PMID:22488186

Davis, Alexis G.; Pietrosimone, Brian G.; Ingersoll, Christopher D.; Pugh, Kelli; Hart, Joseph M.

2011-01-01

16

Relative Activity of Abdominal Muscles during Commonly Prescribed Strengthening Exercises.  

ERIC Educational Resources Information Center

Examined the relative electromyographic (EMG) activity of upper and lower rectus abdominis (LRA) and external oblique (EOA) muscles during five abdominal strengthening exercises. Isometric and dynamic EMG data indicated that abdominal strengthening exercises activated various abdominal muscle groups. For the LRA and EOA muscle groups, there were…

Willett, Gilbert M.; Hyde, Jennifer E.; Uhrlaub, Michael B.; Wendel, Cara L.; Karst, Gregory M.

2001-01-01

17

Does the Addition of Hip Strengthening to a Knee-focused Exercise Program Improve Outcomes in Patients With Patellofemoral Pain Syndrome?  

PubMed

Patellofemoral pain syndrome (PFPS) is one of the most common disorders affecting the lower extremities. In order to improve function and decrease pain, affected individuals often undergo a guided rehabilitation program. Traditional programs have concentrated on quadriceps strengthening and other knee-focused exercises, but recent literature suggests that adding hip muscle strengthening may improve outcomes. This review was conducted to determine the extent to which current evidence supports the addition of hip muscle strengthening to a knee-focused strengthening and stretching program in the treatment of PFPS. PMID:25365356

Bloomer, Ben A; Durall, Chris J

2014-10-29

18

The effect of sports specialization on musculus quadriceps function after exercise-induced muscle damage.  

PubMed

The primary aim of the present study was to examine the effect of eccentric exercise-induced (100 submaximal eccentric contractions at an angular velocity of 60° s?¹, with 20-s rest intervals) muscle damage on peripheral and central fatigue of quadriceps muscle in well-trained long-distance runners, sprint runners, volleyball players, and untrained subjects. We found that (i) indirect symptoms of exercise-induced muscle damage (prolonged decrease in maximal voluntary contraction, isokinetic concentric torque, and electrically induced (20 Hz) torque) were most evident in untrained subjects, while there were no significant differences in changes of muscle soreness and plasma creatine kinase 48 h after eccentric exercise between athletes and untrained subjects; (ii) low-frequency fatigue was greater in untrained subjects and volleyball players than in sprint runners and long-distance runners; (iii) in all subjects, electrically induced (100 Hz) torque decreased significantly by about 20%, while central activation ratio decreased significantly by about 8% in untrained subjects and sprint runners, and by about 3%-5% in long-distance runners and volleyball players. Thus, trained subjects showed greater resistance to exercise-induced muscle damage for most markers, and long-distance runners had no advantage over sprint runners or volleyball players. PMID:22050132

Skurvydas, Albertas; Brazaitis, Marius; Venck?nas, Tomas; Kamandulis, Sigitas; Stanislovaitis, Aleksas; Zuoza, Aurelijus

2011-12-01

19

Muscle metabolism during fatiguing isometric quadriceps exercise in adolescents and adults.  

PubMed

Children and adolescents are less susceptible to muscle fatigue during repeated bouts of high-intensity exercise than adults, but the physiological basis for these differences is not clear. The purpose of the current investigation was to investigate the muscle metabolic responses, using 31-phosphorus magnetic resonance spectroscopy, during fatiguing isometric quadriceps exercise in 13 adolescents (7 females) and 14 adults (8 females). Participants completed 30 maximal voluntary contractions (6-s duration) separated by 6 s of rest. Fatigue was quantified as the relative decrease in force over the test. Fatigue was not significantly different with age (p = 0.20) or sex (p = 0.63). Metabolic perturbation (change in phosphocreatine, inorganic phosphate, and ADP concentrations) was significantly greater in adults compared with adolescents; no sex effects were present. Muscle pH did not differ with age or sex. Phosphocreatine recovery following exercise was not significantly different with age (p = 0.27) or sex (p = 0.97) but a significant interaction effect was present (p = 0.04). Recovery tended to be faster in boys than men but slower in girls than women, though no significant group differences were identified. The results of this study show that at a comparable level of muscle fatigue, the metabolic profile is profoundly different between adolescents and adults. PMID:24669985

Willcocks, Rebecca J; Fulford, Jonathan; Armstrong, Neil; Barker, Alan R; Williams, Craig A

2014-04-01

20

The effects of aerobic exercise and strengthening exercise on pain pressure thresholds.  

PubMed

[Purpose] We assessed the effects of aerobic exercise and strengthening exercise on pain pressure thresholds (PPTs) over time. [Subjects and Methods] Fifteen healthy participants were recruited and randomly divided into 3 groups: aerobic exercise, strengthening exercise, and control. The subjects in the aerobic group walked on a treadmill for 40?min at 6.5?km/h. The subjects in the strength group performed circuit training that included bench press, lat pull down, biceps curl, triceps extension, and shoulder press based on the perceived exertion for 40?min. The subjects in the control group rested without any exercise in a quiet room for 40?min. The PPTs of 5 potential muscle trigger points before exercise, and immediately after 10 and 40?min of exercise or rest were measured using an electronic algometer (JTECH Medical, USA). The Friedman's, Kruskal-Wallis, and Mann-Whitney tests were performed using SPSS 18.0 (IBM, Korea). [Results] The PPTs of all subjects decreased after 10?min of exercise, but the difference was not statistically significant. The PPTs of the control group decreased after 40?min. Furthermore, the PPTs of 3 muscles increased after 40?min of aerobic exercise and of 6 muscles after 40?min of strengthening exercise. No significant difference in PPTs was noted among the groups. [Conclusion] The results show that 40?min is a more appropriate exercise time, although the efficacy of controlling pain did not differ between strengthening exercise and aerobic exercise. PMID:25140106

Lee, Han Suk

2014-07-01

21

Importance of Attenuating Quadriceps Activation Deficits after Total Knee Arthroplasty  

PubMed Central

Total knee arthroplasty (TKA) is associated with persistent quadriceps dysfunction. Since quadriceps dysfunction impairs functional performance, minimizing quadriceps dysfunction by attenuating central activation deficits early after surgery may improve function later in life. Rehabilitation strategies incorporating neuromuscular electrical stimulation and early, aggressive quadriceps strengthening may prove beneficial. Further, surgical approaches such as minimally invasive TKA may minimize post-operative quadriceps dysfunction. PMID:22249398

Thomas, Abbey C.; Stevens-Lapsley, Jennifer E.

2012-01-01

22

Early versus late start of open kinetic chain quadriceps exercises after ACL reconstruction with patellar tendon or hamstring grafts: a prospective randomized outcome study.  

PubMed

The purpose of the present investigation was to evaluate physical outcome after anterior cruciate ligament (ACL) reconstruction with early versus late initiation of open kinetic chain (OKC) exercises for the quadriceps in patients operated on either patellar tendon or hamstring grafts. Sixty-eight patients, 36 males and 32 females, with either patellar tendon graft (34 patients) or hamstring graft (34 patients) were enrolled in this study. All patients were randomly allocated to either early (the 4th postoperative week) or late (the 12th postoperative week) start of OKC exercises for the quadriceps, resulting in four subgroups: patellar tendon reconstruction, early start (P4) or late start (P12) of OKC quadriceps exercises, hamstring tendon reconstruction, early start (H4) or late start (H12) of quadriceps OKC exercises. Prior to surgery and 3, 5 and 7 months later, assessments of range of motion (goniometer), anterior knee laxity (KT-1000), postural sway (KAT 2000), thigh muscle torques (Kin-Com dynamometer) and anterior knee pain (anterior knee pain score) were evaluated. No significant group differences were found in terms of range of motion 3, 5 and 7 months postoperatively. The H4 group showed a significantly higher mean difference of laxity over time of 1.0 mm (CI: 0.18-1.86) than the P4 group (P=0.04). Within the same type of surgery, the H4 against the H12, the mean difference over time was 1.2 mm (0.37-2.1) higher in the H4 group than in the H12 group (P=0.01). There were no significant group differences in terms of postural sway or anterior knee pain at the different test occasions. Significant differences in trends (changes over time) were found when comparing the four groups, for both quadriceps muscle torques (P<0.001) and hamstring muscle torques (P<0.001). All groups, except the P4 group, reached preoperative values of quadriceps muscle torques at the 7 months follow-up. In the H4 and the H12 groups, significantly lower hamstring muscle torques at the 7 months follow-up compared with preoperative values were found. In conclusion, early start of OKC quadriceps exercises after hamstring ACL reconstruction resulted in significantly increased anterior knee laxity in comparison with both late start and with early and late start after bone-patellar tendon-bone ACL reconstruction. Furthermore, the early introduction of OKC exercises for quadriceps did not influence quadriceps muscle torques neither in patients operated on patellar tendon nor hamstring tendon grafts. On the contrary, it appears as if the choice of graft affected the strength of the specific muscle more than the type of exercises performed. Our results could not determine the appropriate time for starting OKC quadriceps exercises for patients who have undergone ACL reconstruction with hamstring tendon graft. Future studies of long-term results of anterior knee laxity and functional outcome are needed. PMID:17219226

Heijne, Annette; Werner, Suzanne

2007-04-01

23

Consumption of oxygen and blood flow during exercise and recovery phase evaluated by near-infrared spectroscopy and its relationship to skin forehead, quadriceps, tympanic, and rectal temperatures  

NASA Astrophysics Data System (ADS)

The availability of oxygen in the human vastus medialis muscle and the tympanic, skin forehead, quadriceps, and rectal temperatures has been investigated during exercise test and post-exercise with non-invasive near-infrared spectroscopy, infrared thermometer, and an array of four thermistors, respectively. During exercise time rectal temperature was not recorded, before exercise basal values were obtained, and after exercise all the data for two hours were recorded. The signals from near-infrared spectroscopy have been studied by analogy to forced vibration and viscously damped free vibration. Other models have been used to evaluate the temperatures. The time necessary for the reoxygenation signal to cross the baseline during the post exercise period was from 30 min to over 100 min. The peak of pH values was 5 min post-exercise and to arrive at basal levels needed 25 min to more than 40 min. The peak of rectal temperature starts around 20 - 30 min post-exercise remaining 25 - 40 min at the same value, starting to slip down slowly at variable intervals of several minutes requiring over two hours to arrive at basal levels. The data obtained by near-infrared spectroscopy and skin quadriceps, rectal temperatures confirm that the oxygen consumption remains after exercise in the muscle studied.

Verdaguer-Codina, Joan; Pujol, P.; Drobnic, F.; Galilea, P.; Riera, J.; Pons, V.; Banquells, M.; Ruiz, O.

1995-12-01

24

Which Treatment is More Effective for Functional Ankle Instability: Strengthening or Combined Muscle Strengthening and Proprioceptive Exercises?  

PubMed Central

[Purpose] The purpose of this study was to implement combined muscle strengthening and proprioceptive exercises to examine the effects of combined exercises on functional ankle instability. [Subjects and Methods] Experiments were conducted with 30 adult males and females. The study subjects were randomly assigned to either a control group (Group A), a muscle strengthening exercise group (Group B), or a combined muscle strengthening and proprioceptive exercise group (Group C) consisting of 10 subjects each. In Group A, measurements were only conducted before and after the experiment without any intervention, whereas the exercise programs for Group B and Group C were implemented three days per week for four weeks. [Results] Muscle strength showed significant increases in Groups B and C compared with the control group during plantar flexion, dorsiflexion, inversion, and eversion. The Cumberland ankle instability tool showed significant increases in Group B and Group C compared with Group A and significant increases in Group C compared with Group B. [Conclusion] Applying combined muscle strengthening and proprioceptive exercises to those who have functional ankle instability is more effective than applying only muscle strengthening exercises. PMID:24707089

Kim, Ki-Jong; Kim, Young-Eok; Jun, Hyun-Ju; Lee, Jin-Su; Ji, Sung-Ha; Ji, Sang-Goo; Seo, Tae-Hwa; Kim, Young-Ok

2014-01-01

25

Early versus late start of open kinetic chain quadriceps exercises after ACL reconstruction with patellar tendon or hamstring grafts: a prospective randomized outcome study  

Microsoft Academic Search

The purpose of the present investigation was to evaluate physical outcome after anterior cruciate ligament (ACL) reconstruction\\u000a with early versus late initiation of open kinetic chain (OKC) exercises for the quadriceps in patients operated on either\\u000a patellar tendon or hamstring grafts. Sixty-eight patients, 36 males and 32 females, with either patellar tendon graft (34\\u000a patients) or hamstring graft (34 patients)

Annette Heijne; Suzanne Werner

2007-01-01

26

Treatment of Knee Osteoarthritis in Relation to Hamstring and Quadriceps Strength  

PubMed Central

[Purpose] To assess the effect of hamstring and quadriceps strengthening exercises on pain intensity, gait velocity, maximum isometric strength, and activities of daily living of patients with knee osteoarthritis (OA). [Subjects and Methods] A total of 20 patients with knee OA, 50 to 65?years of age (57.65 ± 4.78?years), received hot packs, strengthening exercises for the quadriceps and the hamstring muscles and stretching exercises for hamstring muscles. Outcome measures included: the Western Ontario and McMaster Universities OA index questionnaire (WOMAC) scores for assessing health status and health outcomes of knee OA; self-reported pain intensity scores, measured using a visual analogue scale; the 50 ft walk test (a measure of gait velocity and function); and handheld dynamometry (a tool used to measure maximum isometric strength of knee extension and flexion). [Results] There was a significant difference between pre- and post-intervention measures of pain intensity, 50 ft walk times, hamstring strength, and quadriceps strength. Significant differences in WOMAC measures were also observed in the subscales of pain, stiffness and physical function, as well as WOMAC total scores. [Conclusion] Strengthening the hamstring muscles in addition to strengthening the quadriceps muscles proved to be beneficial for perceived knee pain, range of motion, and decreasing the limitation of functional performance of patients with knee OA. PMID:24396198

Hafez, Ashraf Ramadan; Al-Johani, Ahmed H.; Zakaria, Abdul Rahim; Al-Ahaideb, Abdulaziz; Buragadda, Syamala; Melam, Ganeswara Rao; Kachanathu, SJ

2013-01-01

27

Cognitive health benefits of strengthening exercise for community-dwelling older adults  

Microsoft Academic Search

While aerobic exercise has been linked to improved performance on cognitive tasks of executive functioning among older adults, not all older adults can avail themselves of such exercise due to physical limitations. In this study, community-dwelling older adults were evaluated on tasks of executive functioning before and after a month-long strengthening, nonaerobic exercise program. A total of 16 participants who

Cay Anderson-Hanley; Joseph P. Nimon; Sarah C. Westen

2010-01-01

28

Stretching and strengthening exercises: Their effect on three-dimensional scapular kinematics  

Microsoft Academic Search

Objective: To quantitatively evaluate the effects of commonly used shoulder exercises on shoulder kinematics and resting posture.Study Design: A repeated-measures design was used with measurements performed before and after a 6-week exercise program.Method: Twenty asymptomatic subjects with forward shoulder posture were recruited. Stretching exercises for the pectoral muscles and resisted strengthening exercises for the scapular retractors and elevators and the

Che-Hsiang Wang; Philip McClure; Neal E. Pratt; Robert Nobilini

1999-01-01

29

Computational biomechanics of knee joint in open kinetic chain extension exercises  

Microsoft Academic Search

Open kinetic chain (OKC) extension exercises are commonly performed to strengthen quadriceps muscles and restore joint function in performance enhancement programs, in exercise therapies and following joint reconstruction. Using a validated 3D nonlinear finite element model, the detailed biomechanics of the entire joint in OKC extension exercises are investigated at 0, 30, 60 and 90° joint angles. Two loading cases

W. Mesfar; A. Shirazi-Adl

2008-01-01

30

An electromyographical comparison of trunk muscle activity during isometric trunk and dynamic strengthening exercises.  

PubMed

The purpose of this study was to compare rectus abdominis and erector spinae muscle activity during isometric (prone bridge [PB] and superman [SM]) and dynamic strengthening exercises (back squat, front squat [FS], and military press). Participants (n = 10, age 21.8 ± 2.6 years; body mass 82.65 ± 10.80 kg, 174.5± 7.2 cm), performed each exercise in a randomized order, using a repeated-measures design. Electromyographical (EMG) activity (sampling at 2,000 Hz) of the rectus abdominis (RA) and the erector spinae (ES) muscles was recorded throughout the duration of the exercises. Intraclass correlations demonstrated the highest levels of reliability for muscle activity during the isometric exercises; however, all exercises demonstrated high level of reliability (r = 0.764-0.998, p ? 0.01). The PB demonstrated significantly greater (p < 0.01) RA activity compared to all other exercises. The ES activity was significantly (p < 0.01) greater during the FS (1.010 ± 0.308 root mean square value [RMS (V)]) and SM (0.951 ± 0.217 RMS[V]) and compared to all other exercises, although there was no significant difference (p > 0.05) between the FS and the SM exercise. The PB may be the most suitable exercise for strengthening the RA, compared to dynamic exercises at a low to moderate load, because of a higher level of muscle activity. The FS may be a useful alternative to isometric exercises when strengthening the ES, because it results in slightly higher muscle activity levels when using only a light to moderate load. Because of the dynamic nature of the FS, this may also be more beneficial in transferring to activities of daily living and sporting environments. PMID:21157393

Comfort, Paul; Pearson, Stephen J; Mather, David

2011-01-01

31

Exercise for patients with osteoporosis: management of vertebral compression fractures and trunk strengthening for fall prevention.  

PubMed

Maintenance of bone health and quality requires mechanical strain, but the mechanical force needs to be within the bone's biomechanical competence. In osteoporosis, compression of vertebral bodies can be insidious. Therefore, absence of pain does not necessarily indicate absence of vertebral microfracture and deformity. Further, patients with previous vertebral fractures are at risk for further vertebral fractures and their associated morbidity. Exercise is a part of the comprehensive management of patients with osteoporosis and has been associated with improvement of quality of life and lowered risk of future fracture. The exercise prescription needs to match the needs of the patient. If exercise is not prescribed properly, then it may have negative consequences. In general, an exercise program, therapeutic or recreational, needs to address flexibility, muscle strength, core stability, cardiovascular fitness, and gait steadiness. As with pharmacotherapy, therapeutic exercises need to be individualized on the basis of musculoskeletal status and an individual's exercise interest. In osteoporosis, axial strength and stability are of primary importance. In particular, a spinal extensor strengthening program should be performed with progressive measured resistance as tolerated. To address falls and fractures, an exercise program should also include balance and lower extremity strength training. Proper dosing of oral cholecalciferol and calcium supplements can enhance the effect of strengthening exercises. Finally, a coordinated approach, such as the Spinal Proprioception Extension Exercise Dynamic (SPEED) program, can improve back extensor strength, the level of physical activity, and locomotion, and reduce back pain and fear and risk of falls. PMID:23174554

Sinaki, Mehrsheed

2012-11-01

32

Effects of individual strengthening exercises on subdivisions of the gluteus medius in a patient with sacroiliac joint pain.  

PubMed

[Purpose] We investigated the effects of individual strengthening exercises for subdivisions of the gluteus medius in a patient with sacroiliac joint pain. [Subject] A 32?year-old female who complained of pain in the posterior area of the left iliac crest and sacroiliac joints over a period of 6 months was the subject of this study. [Methods] She performed individual strengthening exercises for subdivisions of the gluteus medius over 3 weeks. Pain-provocation tests and VAS scores were evaluated before and after the intervention. [Results] After individual strengthening exercises for subdivisions of the gluteus medius, the subject showed no pain in the Gaenslen, Patrick, or REAB tests for the left sacroiliac joint. The VAS score was less the 3/10, compared with 7/10 initially. [Conclusion] Individual strengthening exercises for the subdivisions of the gluteus medius were effective at reducing SI joint pain for this patient. PMID:25276045

Yoo, Won-Gyu

2014-09-01

33

PERCEIVED LOADING AND MUSCLE ACTIVITY DURING HIP STRENGTHENING EXERCISES: COMPARISON OF ELASTIC RESISTANCE AND MACHINE EXERCISES  

PubMed Central

Objective: Decreased hip muscle strength is frequently reported in patients with hip injury or pathology. Furthermore, soccer players suffering from groin injury show decreased strength of hip muscles. Estimating 10?repetition maximum can be time?consuming and difficult, thus, using the Borg category rating 10 scale (Borg CR10 scale) can be a useful tool for estimating the intensity of exercise. The aims of this study were 1) to investigate the feasibility of the use of the Borg CR10 scale for rating strength training intensity of the hip abductor and hip adductor muscles, and 2) to compare hip muscle activity during hip abduction and hip adduction exercises using elastic resistance and isotonic machines, using electromyography (EMG). Methods: EMG activity was recorded from 11 muscles at the hip, thigh and trunk during hip adduction and hip abduction exercises in 16 untrained women, using elastic resistance and isotonic exercise machines. These recordings were normalized to maximal voluntary contraction (MVC) EMG (nEMG). The exercises were performed at four levels of perceived loading reported using the Borg CR10: light (Borg ?2), moderate (Borg >2–<5), heavy (Borg ?5–<7) and near maximum (Borg ?7). Results: Moderate to strong associations were observed between perceived loading and nEMG obtained during the adduction exercise with elastic resistance (r=0.8±0.3) as well as in machine (r=0.69±0.55) and the abduction exercise with elastic resistance (r=0.66±0.29) as well as in machine (r =0.62±0.54). The abduction exercise performed with elastic resistance displayed significantly higher gluteus medius nEMG recruitment than the in machine exercise. Conclusions: The results of this study show that the Borg CR10 scale can be a useful tool for estimating intensity levels during resistance training of the hip adductor and hip abductor muscles. Although elastic resistance and exercise machine seem equally effective for recruiting muscle activity of the hip adductors, the elastic resistance condition was able to demonstrate greater muscle recruitment than the exercise machine during hip abduction. PMID:24377067

Jakobsen, Markus Due; Thorborg, Kristian; Sundstrup, Emil; Jay, Kenneth; Andersen, Lars L.

2013-01-01

34

No effect of forearm band and extensor strengthening exercises for the treatment of tennis elbow: a prospective randomised study  

Microsoft Academic Search

The objective of this prospective randomised study was to analyse the effect of the forearm support band and of strengthening\\u000a exercises for the treatment of tennis elbow. Twenty-nine patients with 30 tennis elbows were randomised into 3 groups of treatment:\\u000a (I) forearm support band, (II) strengthening exercises and (III) both methods. The patients had a standardised examination\\u000a at their first

Rolf Luginbühl; Florian Brunner; Alberto G. Schneeberger

2008-01-01

35

Scapular muscle activity from selected strengthening exercises performed at low and high intensities.  

PubMed

A balanced level of muscle strength between the different parts of the scapular muscles is important in optimizing performance and preventing injuries in athletes. Emerging evidence suggests that many athletes lack balanced strength in the scapular muscles. Evidence-based recommendations are important for proper exercise prescription. This study determines scapular muscle activity during strengthening exercises for scapular muscles performed at low and high intensities (Borg CR10 levels 3 and 8). Surface electromyography (EMG) from selected scapular muscles was recorded during 7 strengthening exercises and expressed as a percentage of the maximal EMG. Seventeen women (aged 24-55 years) without serious disorders participated. Several of the investigated exercises-press-up, prone flexion, one-arm row, and prone abduction at Borg 3 and press-up, push-up plus, and one-arm row at Borg 8-predominantly activated the lower trapezius over the upper trapezius (activation difference [?] 13-30%). Likewise, several of the exercises-push-up plus, shoulder press, and press-up at Borg 3 and 8-predominantly activated the serratus anterior over the upper trapezius (?18-45%). The middle trapezius was activated over the upper trapezius by one-arm row and prone abduction (?21-30%). Although shoulder press and push-up plus activated the serratus anterior over the lower trapezius (?22-33%), the opposite was true for prone flexion, one-arm row, and prone abduction (?16-54%). Only the press-up and push-up plus activated both the lower trapezius and the serratus anterior over the upper trapezius. In conclusion, several of the investigated exercises both at low and high intensities predominantly activated the serratus anterior and lower and middle trapezius, respectively, over the upper trapezius. These findings have important practical implications for exercise prescription for optimal shoulder function. For example, both workers with neck pain and athletes at risk of shoulder impingement (e.g., overhead sports) should perform push-up plus and press-ups to specifically strengthen the serratus anterior and lower trapezius. PMID:22076101

Andersen, Christoffer H; Zebis, Mette K; Saervoll, Charlotte; Sundstrup, Emil; Jakobsen, Markus D; Sjøgaard, Gisela; Andersen, Lars L

2012-09-01

36

Reduced Quadriceps Motor-Evoked Potentials in an Individual with Unilateral Knee Osteoarthritis: A Case Report  

PubMed Central

One male with unilateral osteoarthritis (OA) of the knee underwent testing of corticospinal (CS) excitability (as quantified from motor-evoked potentials (MEPs) in the rectus femoris (RF) using transcranial magnetic stimulation) and quadriceps muscle strength. Baseline data indicated reduced MEP amplitudes in the RF of the affected limb compared to the unaffected limb. Increases in RF MEP amplitudes from both limbs were observed immediately following a 30-minute exercise session focusing on muscle strengthening. Following an 8-week muscle strengthening intervention, the participant exhibited increased MEP amplitudes and muscle strength in the affected limb. These findings suggest that alterations in peripheral muscle function found in patients with knee OA may have an origin centrally within the motor cortex and that interlimb differences may be evident in those with unilateral disease. These findings also suggest that CS excitability may be improved following a muscle strengthening intervention. PMID:22937446

Hunt, Michael A.; Zabukovec, Jeanie R.; Peters, Sue; Pollock, Courtney L.; Linsdell, Meghan A.; Boyd, Lara A.

2011-01-01

37

Strengthening Exercises Improve Symptoms and Quality of Life but Do Not Change Autonomic Modulation in Fibromyalgia: A Randomized Clinical Trial  

PubMed Central

Objective Autonomic dysfunction is an important mechanism that could explain many symptoms observed in fibromyalgia (FM). Exercise is an effective treatment, with benefits potentially mediated through changes in autonomic modulation. Strengthening is one of the less studied exercises in FM, and the acute and chronic effects of strengthening on the autonomic system remain unknown. The objective of this study was to assess the chronic effects of strengthening exercises (STRE) on autonomic modulation, pain perception and the quality of life (QOL) of FM patients. Methods Eighty sedentary women with FM (ACR 1990) were randomly selected to participate in STRE or flexibility (FLEX) exercises in a blinded controlled trial. The intensity of STRE was set at 45% of the estimated load of 1 Repetition Maximum (RM) in 12 different exercises. Outcomes were Visual Analog Scale (VAS) for pain, Heart Rate Variability (HRV) analysis, treadmill test, the sit and reach test (Wells and Dillon’s Bench), maximal repetitions test and handgrip dynamometry; and quality of life by the Fibromyalgia Impact Questionnaire (FIQ), the Beck and Idate Trait-State Inventory (IDATE), a short-form health survey (SF-36). Results The STRE group was more effective to strength gain for all muscles and pain control after 4 and 16 weeks (p<0.05). The FLEX group showed higher improvements in anxiety (p<0.05). Both groups showed improvements in the QOL, and there was no significant difference observed between the groups. There was no change in the HRV of the STRE and FLEX groups. Conclusions Strengthening exercises show greater and more rapid improvements in pain and strength than flexibility exercises. Despite the benefits in fitness, pain, depression, anxiety and quality of life, no effect was observed on the autonomic modulation in both groups. This observation suggests that changes in autonomic modulation are not a target tobe clinically achieved in fibromyalgia. Trial Registration ClinicalTrials.gov NCT02004405 PMID:24651512

Gavi, Maria Bernadete Renoldi Oliveira; Vassalo, Dalton Valentin; Amaral, Fabian Tadeu; Macedo, Danielle Constância Felício; Gava, Pablo Lúcio; Dantas, Eduardo Miranda; Valim, Valéria

2014-01-01

38

Effects of individual strengthening exercises for the stabilization muscles on the nutation torque of the sacroiliac joint in a sedentary worker with nonspecific sacroiliac joint pain  

PubMed Central

[Purpose] We investigated the effects of individual strengthening exercises for the stabilization muscles on the nutation torque of the sacroiliac joint in a sedentary worker with nonspecific sacroiliac joint pain. [Subject] A 36-year-old female complained of pain in the sacroiliac joints. [Methods] The subject performed individual strengthening exercises for the stabilization muscles for nutation torque of the sacroiliac joint for 3 weeks. Pain-provocation tests and visual analog scale (VAS) scores were evaluated before and after the exercises. [Results] After performing the individual strengthening exercises for the erector spinae, rectus abdominis, and biceps femoris muscles for 3 weeks, the subject displayed no pain in the pain provocation tests, and the VAS score was 2/10. [Conclusion] The individual strengthening exercises for the stabilization muscles of the sacroiliac joint performed in the present study appear to be effective for sedentary workers with sacroiliac joint pain.

Yoo, Won-gyu

2015-01-01

39

Home-Based Leg Strengthening Exercise Improves Function One Year After Hip Fracture: A Randomized Controlled Study  

PubMed Central

Objectives Examine the effectiveness of a short term leg strengthening exercise program compared to attentional control on improving strength, walking abilities, and function one year after hip fracture. Design Randomized controlled pilot study. Setting Interventions occurred in patients’ homes. Participants Community-dwelling older adults (n=26) six months post hip fracture at baseline. Intervention Exercise and control participants received interventions by physical therapists twice weekly for 10 weeks. The exercise group received high intensity leg strengthening exercises. The control group received transcutaneous electrical nerve stimulation and mental imagery. Measurements Isometric force production of lower extremity muscles; usual and fast gait speed, six minute walk (6-MW) distance, modified physical performance test (mPPT), and SF-36 physical function. Results The primary endpoint was at one year post fracture. Isometric force production (p<.01), usual and fast gait speed (p=.02 & .03, respectively), 6-MW (p<.01), and mPPT (p<.01) improved at one year post fracture with exercise. Effect sizes were 0.79 for strength, 0.81 for mPPT scores, 0.56 for gait speed, 0.49 for 6-MW, and 0.30 for SF-36 scores. More patients in the exercise group made meaningful changes in gait speed and 6-MW distance than control patients (?2: p=.004). Conclusion A 10-week home-based progressive resistance exercise program was sufficient to achieve moderate to large effects on physical performance and quality of life and may offer an alternative intervention mode for hip fracture patients who are unable to leave home at 6 months after the fracture. The effects were maintained at 3 months after completion of the training program. PMID:20929467

Mangione, Kathleen K.; Craik, Rebecca L.; Palombaro, Kerstin M.; Tomlinson, Susan S.; Hofmann, Mary T.

2010-01-01

40

The Effect of NeuroMuscular Electrical Stimulation on Quadriceps Strength and Knee Function in Professional Soccer Players: Return to Sport after ACL Reconstruction  

PubMed Central

The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction) on the quadriceps muscle. The 80 participants (NMES = 40, control = 40) received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500?Hz, and train of pulses frequency: 50?Hz) three times daily (3 hours of break between treatments), 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months) were applied. The results of this study show that NMES (in presented parameters in experiment) is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741. PMID:24381943

Taradaj, J.; Halski, T.; Kucharzewski, M.; Walewicz, K.; Smykla, A.; Ozon, M.; Slupska, L.; Dymarek, R.; Ptaszkowski, K.; Rajfur, J.; Pasternok, M.

2013-01-01

41

The Effect of Warm-Up and Cool-Down Exercise on Delayed Onset Muscle Soreness in the Quadriceps Muscle: a Randomized Controlled Trial  

PubMed Central

The aim of the present study was to investigate the effect of warm-up and cool-down exercise on delayed onset of muscle soreness at the distal and central parts of rectus femoris following leg resistance exercise. Thirty-six volunteers (21 women, 15 men) were randomly assigned to the warm-up (20 min ergometer cycling prior to the resistance exercise), cool-down (20 min cycling after the resistance exercise), or control group performing resistance exercise only. The resistance exercise consisted of front lunges (10×5 repetitions/sets) with external loading of 40% (women) and 50% (men) of body mass. Primary outcomes were pressure pain threshold along rectus femoris and maximal isometric knee extension force. Data were recorded before the resistance exercise and on the two consecutive days. Pressure pain threshold at the central muscle belly was significantly reduced for the control group on both day 2 and 3 (p?0.003) but not for the warm-up group (p?0.21). For the cool-down group, pressure pain threshold at the central muscle belly was significantly reduced on day 2 (p?0.005) and was also lower compared to the warm-up group (p=0.025). Force was significantly reduced on day 2 and 3 for all groups (p<0.001). This study indicates that aerobic warm-up exercise performed prior to resistance exercise may prevent muscle soreness at the central but not distal muscle regions, but it does not prevent loss of muscle force. PMID:23486850

Olsen, Olav; Sjøhaug, Mona; van Beekvelt, Mireille; Mork, Paul Jarle

2012-01-01

42

Different changes of quantity due to aging in the psoas major and quadriceps femoris muscles in women.  

PubMed

Bone fractures cause disabilities that leave the elderly bedridden and strengthening the muscles of the lower limbs, especially the quadriceps femoris, is the main kinematical method of preventing falls. Recently, however, it has become clear that the psoas major is critical for walking ability. We examined changes due to aging in the size of the psoas major compared with changes in the quadriceps femoris. Bone fractures are more frequent in women than in men; our participants (n=210) were therefore exclusively women ranging in age from 20 to 79 and divided into 6 age groups (n=35 each) in 10-year increments. Cross-sectional areas of the two muscles were measured by an MR scanner for a comparative estimation of muscle size. The psoas major showed the greatest quantity in subjects in their 20s, after which it declined steadily until the 60s and dramatically in the 70s, while the area of the quadriceps femoris was preserved until the 40s and showed no dramatic later decline. Exercise beyond regular daily activities is recommended to prevent the psoas major from decreasing in volume. We also recommend the development of a method of maintaining its muscle volume which would target women younger than 40 and older than 60. PMID:16849833

Takahashi, K; Takahashi, H E; Nakadaira, H; Yamamoto, M

2006-01-01

43

Mechanisms Undlerlying Quadriceps Weakness in Knee Osteoarthritis  

PubMed Central

Purpose To identify determinants of quadriceps weakness among persons with end-stage knee osteoarthritis (OA). Methods One-hundred twenty-three individuals (mean age 64.9 ± 8.5 yr) with Kellgren/Lawrence grade IV knee OA participated. Quadriceps strength (MVIC) and volitional muscle activation (CAR) were measured using a burst superimposition test. Muscle composition (lean muscle cross-sectional area (LMCSA) and fat CSA (FCSA)) were quantified using magnetic resonance imaging. Specific strength (MVIC/LMCSA) was computed. Interlimb differences were analyzed using paired-sample t-tests. Regression analysis was applied to identify determinants of MVIC. An alpha level of 0.05 was adopted. Results The OA limb was significantly weaker, had lower CAR, and had smaller LMCSA than the contralateral limb. CAR explained 17% of the variance in the contralateral limb's MVIC compared with 40% in the OA limb. LMCSA explained 41% of the variance in the contralateral limb's MVIC compared with 27% in the OA limb. Conclusion Both reduced CAR and LMCSA contribute to muscle weakness in persons with knee OA. Similar to healthy elders, the best predictor of strength in the contralateral, nondiseased limb was largely determined by LMCSA, whereas CAR was found to be the primary determinant of strength in the OA limb. Deficits in CAR may undermine the effectiveness of volitional strengthening programs in targeting quadriceps weakness in the OA population. PMID:18379202

PETTERSON, STEPHANIE C.; BARRANCE, PETER; BUCHANAN, THOMAS; BINDER-MACLEOD, STUART; SNYDER-MACKLER, LYNN

2013-01-01

44

Hamstring\\/quadriceps ratios in college football players: A high velocity evaluation  

Microsoft Academic Search

Hamstring\\/quadriceps ratios were assessed on 60 in tercollegiate football players at functional speeds of 90, 180, and 300 deg\\/sec on the Cybex II. The ratio rose as velocity of exercise increased and the quadriceps was stronger than the hamstrings at all speeds. The flexor\\/extensor ratio differed bilaterally at all speeds with ratio lower for the dominant knee.The study helped establish

Maureen G. Stafford; William A. Grana

1984-01-01

45

Targeting quadriceps inhibition with electromyographic biofeedback: a neuroplastic approach.  

PubMed

Weakness of the quadriceps is a common occurrence in patients after knee injury or surgery; this weakness is due to a natural mechanism known as arthrogenic muscle inhibition. If inhibition of the quadriceps persists, it can become detrimental to a patient's function and lead to additional pathologies. A number of therapeutic interventions have be used in the rehabilitation of these patients, but few have proven to be successful. Electromyographic biofeedback is one modality that has demonstrated positive outcomes in patients by restoring quadriceps function. However, the reason for the effectiveness of this modality has yet to be fully explained in the area of rehabilitation. Neuroplasticity is a phenomenon that has gained much attention in rehabilitation, and its potential continues to grow. After an injury, the brain has the ability to enhance recovery by strengthening its neural circuitry. Through rehabilitation, clinicians can use attentional strategies to foster neuroplasticity and promote the recovery of their patients. In this article we provide reasoning for the effectiveness of electromyographic biofeedback using the evidence of neuroplasticity. With this information, we hope to provide clinicians a rationale for using this tool in the rehabilitation of patients with persistent quadriceps inhibition. PMID:24580566

Gabler, Conrad; Kitzman, Patrick H; Mattacola, Carl G

2013-01-01

46

The Prevalence of Quadriceps Weakness in COPD and the Relationship with Disease Severity  

PubMed Central

Rationale and objectives Quadriceps strength relates to exercise capacity and prognosis in chronic obstructive pulmonary disease (COPD). We wished to quantify the prevalence of quadriceps weakness in COPD, and hypothesised that it would not be restricted to patients with severe airflow obstruction or dyspnoea. Methods Predicted quadriceps strength was calculated using a regression equation (incorporating age, gender, height and fat-free mass), based on measurements from 212 healthy subjects. The prevalence of weakness (defined as observed values 1.645 standardised residuals below predicted) was related to GOLD stage and Medical Research Council (MRC) dyspnoea score in two cohorts of stable COPD outpatients recruited from the United Kingdom (n=240) and the Netherlands (n=351). Main results 32% and 33% of UK and Dutch COPD patients had quadriceps weakness. A significant proportion of patients in GOLD stages 1 and 2, or with an MRC dyspnoea score of 1 or 2, had quadriceps weakness (28% and 26% respectively). These values rose to 38% in GOLD stage 4, and 43% in patients with an MRC Score of 4 or 5. Conclusion Quadriceps weakness was demonstrable in one-third of COPD patients attending hospital respiratory outpatient services. Quadriceps weakness exists in the absence of severe airflow obstruction or breathlessness. PMID:19897554

Seymour, JM; Spruit, MA; Hopkinson, NS; Sathyapala, SA; Man, WD-C; Jackson, A; Gosker, HR; Schols, AMWJ; Moxham, J; Polkey, MI; Wouters, EFM

2011-01-01

47

Quadriceps Fatigue Alters Human Muscle Performance during a Novel Weight Bearing Task  

PubMed Central

Limited information is currently available regarding muscle synergistic patterns and triggered reflex responses during dynamic weight bearing activities in the presence of muscle fatigue. Purpose The purpose of this study was to examine the effects of quadriceps muscle fatigue on patterns of muscle activation and performance in response to sudden, unexpected perturbations during a weight-bearing task. Methods Motion of the knee was measured as subjects were asked to track a visual target as accurately as possible while performing a resisted single leg squat task. Random perturbations were delivered in 20% of the trials by unexpectedly releasing the resistance during the flexion phase of the exercise. Absolute and constant errors were calculated to evaluate target tracking performance. Quadriceps and hamstring muscle activity was recorded during both perturbed and unperturbed trials. Twelve healthy females were tested before and after completing a repetitive submaximal eccentric quadriceps fatigue protocol. A second group of 12 females served as controls. Unexpected perturbations elicited long latency responses characterized by facilitation of the quadriceps and inhibition of the hamstrings. Results Muscle fatigue increased the amplitude of the long latency response in vastus lateralis by 4.3% maximum voluntary isometric contraction (p=.004). Changes in tracking error occurred in response to perturbations after fatigue in spite of significantly increased quadriceps muscle activity, especially during the extension phase of the exercise. Conclusion Quadriceps muscle fatigue alters the patterns of coordinated muscle activity and may render subjects less able to cope with unexpected perturbations during weight bearing tasks. PMID:20164810

Ballantyne, Bryon T.; Shields, Richard K.

2010-01-01

48

Influence of Resistance Exercise Training to Strengthen Muscles across Multiple Joints of the Lower Limbs on Dynamic Balance Functions of Stroke Patients  

PubMed Central

[Purpose] The objective of this study was to evaluate the effects of resistance exercise training for strengthening muscles across multiple joints on the dynamic balance function of stroke patients. [Subjects and Methods] Subjects in the training group (n=14) and the control group (n=14) received conservative physical therapy for 30 minutes per day, five days per week, for a period of six weeks. The training group additionally performed three sets (eight to 10 repetitions per set) of resistance exercise at 70% of the 1-repetition maximum (1RM) to strengthen muscles across multiple joints. The control group did the same exercises for the same duration but without resistance. To assess dynamic balance function, before and after the intervention, we measured antero-posterior (A-P) and medio-lateral (M-L) sway distances, the Berg balance scale (BBS), and the timed up and go (TUG) times. [Results] Compared to pre-intervention values, the BBS score showed significant increases in both groups, and A-P and M-L sway distances and TUG times showed significant decreases in both groups. Changes in A-P and M-L sway distances, BBS scores, and TUG times were significantly different between the muscle training group and the control group. [Conclusion] Training involving muscle strength across multiple joints is an effective intervention for improvement of dynamic balance function of stroke patients. PMID:25202193

Son, Sung Min; Park, Myung Kyu; Lee, Na Kyung

2014-01-01

49

Preferential reduction of quadriceps over respiratory muscle strength and bulk after lung transplantation for cystic fibrosis  

PubMed Central

Background: In the absence of complications, recipients of lung transplants for cystic fibrosis have normal pulmonary function but the impact of the procedure on the strength and bulk of respiratory and limb muscles has not been studied. Methods: Twelve stable patients who had undergone lung transplantation for cystic fibrosis 48 months earlier (range 8–95) and 12 normal subjects matched for age, height, and sex were studied. The following parameters were measured: standard lung function, peak oxygen uptake by cycle ergometry, diaphragm surface area by computed tomographic (CT) scanning, diaphragm and abdominal muscle thickness by ultrasonography, twitch transdiaphragmatic and gastric pressures, quadriceps isokinetic strength, and quadriceps cross section by CT scanning, and lean body mass. Diaphragm mass was computed from diaphragm surface area and thickness. Results: Twitch transdiaphragmatic and gastric pressures, diaphragm mass, and abdominal muscle thickness were similar in the two groups but quadriceps strength and cross section were decreased by nearly 30% in the patients. Patients had preserved quadriceps strength per unit cross section but reduced quadriceps cross section per unit lean body mass. The cumulative dose of corticosteroids was an independent predictor of quadriceps atrophy. Peak oxygen uptake showed positive correlations with quadriceps strength and cross section in the two groups, but peak oxygen uptake per unit quadriceps strength or cross section was reduced in the patient group. Conclusions: The diaphragm and abdominal muscles have preserved strength and bulk in patients transplanted for cystic fibrosis but the quadriceps is weak due to muscle atrophy. This atrophy is caused in part by corticosteroid therapy and correlates with the reduction in exercise capacity. PMID:15333856

Pinet, C; Scillia, P; Cassart, M; Lamotte, M; Knoop, C; Melot, C; Estenne, M

2004-01-01

50

Peak Torque, average power, and hamstring\\/quadriceps ratios in nondisabled adults and adults with mental retardation  

Microsoft Academic Search

Objective: To compare isokinetic hamstring and quadriceps peak torque (Nm), average power (watts), and corresponding hamstring\\/quadriceps (HQ) ratios (as percentages) of adult men with Down syndrome (DS), with mental retardation without Down syndrome (NDS), and nondisabled sedentary controls (SC).Design: Repeated measures analysis of variance.Setting: Subjects were tested at a university exercise science laboratory.Subjects: Volunteer sample of 35 subjects: SC (n

Ronald V. Croce; Kenneth H. Pitetti; Michael Horvat; John Miller

1996-01-01

51

CONTRALATERAL EFFECTS OF DISINHIBITORY TENS ON QUADRICEPS FUNCTION IN PEOPLE WITH KNEE OSTEOARTHRITIS FOLLOWING UNILATERAL TREATMENT  

PubMed Central

Background: Quadriceps activation failure is common in patients with tibiofemoral osteoarthritis (TFOA) and has been reported to occur bilaterally following acute and chronic knee injuries. Sensory transcutaneous electrical stimulation (TENS) applied to the knee has increased ipsilateral quadriceps activation, yet it remains unknown if repeated sensory TENS treatments affect activation in the contralateral quadriceps. Objective: To determine the effects of unilateral TENS treatment to the involved leg, in conjunction with 4-weeks of therapeutic exercise, on volitional quadriceps activation in the contralateral leg. Methods: Thirty-three patients with radiographically diagnosed TFOA were randomly assigned to the TENS, placebo, and the control groups. The involved leg was defined as the knee with highest degree of radiographically assessed TFOA. All participants completed a supervised 4-week lower extremity exercise program for the involved leg only. TENS and placebo TENS were worn throughout the rehabilitation sessions as well as during daily activities for those groups on the involved leg. Quadriceps central activation ratio (CAR), a measure of volitional muscular activation, was assessed in the uninvolved leg at baseline, 2-weeks and 4-weeks following the initiation of the intervention. Results: There were no differences between groups for quadriceps CAR (P=0.3). Discussion: Although significant differences were not found, strong to moderate within group effect sizes were calculated for the TENS group at 2 (d = .87) and 4 weeks (d = .54), suggesting that significant differences may be found in a larger population. Conclusions: Contralateral quadriceps CAR was not affected following a 4-week unilateral disinhibitory intervention in this sample. PMID:21589667

Saliba, Susan A.; Hart, Joseph M.; Hertel, Jay; Ingersoll, Christopher D.

2010-01-01

52

... strengthen the fight to end violence against women, and ensure that all women can exercise their right to live in safety in a peaceful society. In Quebec, women make  

E-print Network

intimate partner. ...counter inequalities between women and men, by opposing discrimination against women... strengthen the fight to end violence against women, and ensure that all women can exercise their right to live in safety in a peaceful society. In Quebec, women make up 80% of victims of domestic

Toronto, University of

53

Exercise  

MedlinePLUS

Exercise - National Multiple Sclerosis Society Skip to navigation Skip to content Menu Navigation National Multiple Sclerosis Society Sign In In Your Area ... now Download now Publication Stretching for People with MS Illustrated manual showing range of motion, stretching, and ...

54

Intra- and intermuscular variation in human quadriceps femoris architecture assessed in vivo  

PubMed Central

Despite the functional importance of the human quadriceps femoris in movements such as running, jumping, lifting and climbing, and the known effects of muscle architecture on muscle function, no research has fully described the complex architecture of this muscle group. We used ultrasound imaging techniques to measure muscle thickness, fascicle angle and fascicle length at multiple regions of the four quadriceps muscles in vivo in 31 recreationally active, but non-strength-trained adult men and women. Our analyses revealed a reasonable similarity in the superficial quadriceps muscles, which is suggestive of functional similarity (at least during the uni-joint knee extension task) given that they act via a common tendon. The deep vastus intermedius (VI) is architecturally dissimilar and therefore probably serves a different function(s). Architecture varies significantly along the length of the superficial muscles, which has implications for the accuracy of models that assume a constant intramuscular architecture. It might also have consequences for the efficiency of intra- and intermuscular force transmission. Our results provide some evidence that subjects with a given architecture of one superficial muscle, relative to the rest of the subject sample, also have a similar architecture in other superficial muscles. However, this is not necessarily true for vastus lateralis (VL), and was not the case for VI. Therefore, the relative architecture of one muscle cannot confidently be used to estimate the relative architecture of another. To confirm this, we calculated a value of whole quadriceps architecture by four different methods. Regardless of the method used, we found that the absolute or relative architecture of one muscle could not be used as an indicator of whole quadriceps architecture, although vastus medialis, possibly in concert with VL and the anterior portion of VI, could be used to provide a useful snapshot. Importantly, our estimates of whole quadriceps architecture show a gender difference in whole quadriceps muscle thickness, and that muscle thickness is positively correlated with fascicle angle whereas fascicle length is negatively, although weakly, correlated with fascicle angle. These results are supportive of the validity of estimates of whole quadriceps architecture. These data are interpreted with respect to their implications for neural control strategies, region-specific adaptations in muscle size in response to training, and gender-dependent differences in the response to exercise training. PMID:16928199

Blazevich, Anthony J; Gill, Nicholas D; Zhou, Shi

2006-01-01

55

Aerobic, Muscle- and Bone-Strengthening: What Counts?  

MedlinePLUS

... strengthening Games such as tug of war Modified push-ups (with knees on the floor) Resistance exercises using ... bars Gymnastics Games such as tug of war Push-ups Resistance exercises with exercise bands, weight machines, hand- ...

56

Transcranial Magnetic Stimulation and Volitional Quadriceps Activation  

PubMed Central

Abstract Context: Quadriceps-activation deficits have been reported after meniscectomy. Transcranial magnetic stimulation (TMS) in conjunction with maximal contractions affects quadriceps activation in patients after meniscectomy. Objective: To determine the effect of single-pulsed TMS on quadriceps central activation ratio (CAR) in patients after meniscectomy. Design: Randomized controlled clinical trial. Setting: University laboratory. Patients or Other Participants: Twenty participants who had partial meniscectomy and who had a CAR less than 85% were assigned randomly to the TMS group (7 men, 4 women; age ?=? 38.1 ± 16.2 years, height ?=? 176.8 ± 11.5 cm, mass ?=? 91.8 ± 27.5 kg, postoperative time ?=? 36.7 ± 34.9 weeks) or the control group (7 men, 2 women; age ?=? 38.2 ± 17.5 years, height ?=? 176.5 ± 7.9 cm, mass ?=? 86.2 ± 15.3 kg, postoperative time ?=? 36.6 ± 37.4 weeks). Intervention(s): Participants in the experimental group received TMS over the motor cortex that was contralateral to the involved leg and performed 3 maximal quadriceps contractions with the involved leg. The control group performed 3 maximal quadriceps contractions without the TMS. Main Outcome Measure(s): Quadriceps activation was assessed using the CAR, which was measured in 70° of knee flexion at baseline and at 0, 10, 30, and 60 minutes posttest. The CAR was expressed as a percentage of full activation. Results: Differences in CAR were detected over time (F4,72 ?=? 3.025, P ?=?.02). No interaction (F4,72 ?=? 1.457, P ?=? .22) or between-groups differences (F1,18 ?=? 0.096, P ?=? .76) were found for CAR. Moderate CAR effect sizes were found at 10 (Cohen d ?=? 0.54, 95% confidence interval [CI] ?=? ?0.33, 1.37) and 60 (Cohen d ?=? 0.50, 95% CI ?=? ?0.37, 1.33) minutes in the TMS group compared with CAR at baseline. Strong effect sizes were found for CAR at 10 (Cohen d ?=? 0.82, 95% CI ?=? ?0.13, 1.7) and 60 (Cohen d ?=? 1.06, 95% CI ?=? 0.08, 1.95) minutes in the TMS group when comparing percentage change scores between groups. Conclusions: No differences in CAR were found between groups at selected points within a 60-minute time frame, yet moderate to strong effect sizes for CAR were found at 10 and 60 minutes in the TMS group, indicating increased activation after TMS. PMID:21062180

Gibbons, Christopher E.; Pietrosimone, Brian G.; Hart, Joseph M.; Saliba, Susan A.; Ingersoll, Christopher D.

2010-01-01

57

Measurement of quadriceps endurance by fNIRS  

NASA Astrophysics Data System (ADS)

In this paper, the changes in muscle deoxygenation trends during a sustained isometric quadriceps (chair squat/half squat) endurance exercise were evaluated among twelve male subjects and the relationship between muscle oxygenation and endurance times was investigated by means of functional near-infrared spectroscopy (fNIRS). Neuromuscular activation and predictions of muscle performance decrements during extended fatiguing task was investigated by means of surface electromyography (sEMG). The results of the study showed that in the subjects who maintained exercise longer than five minutes (group 1), mean Hb recovery time (33 [sec.]) was 37.4% less than the others (group 2, 52.7 [sec.]). Also mean HbO II decline amplitude (2.53 [a.u.] in group 1 and 2.07 [a.u.] in group 2) and oxy decline amplitude (8.4 [a.u.] in group 1 and 3.04 [a.u.] in group 2) in the beginning of squat exercise are found to be 22.6% and 176.9% bigger in these group. For the EMG parameters, mean slope of MNF and MDF decline are found to be 57.5% and 42.2% bigger in magnitude in group 2 which indicates higher degree of decrement in mean and median frequencies although their mean squat duration time is less. This indicates higher index of fatigue for this group. It is concluded that training leads to altered oxygenation and oxygen extraction capability in the exercising muscle and investigated fNIRS parameters could be used for endurance evaluation.

Erdem, Devrim; ?ayli, Ömer; Karahan, Mustafa; Akin, A.

2006-02-01

58

Quadriceps and Respiratory Muscle Fatigue Following High-Intensity Cycling in COPD Patients  

PubMed Central

Exercise intolerance in COPD seems to combine abnormal ventilatory mechanics, impaired O2 transport and skeletal muscle dysfunction. However their relatie contribution and their influence on symptoms reported by patients remain to be clarified. In order to clarify the complex interaction between ventilatory and neuromuscular exercise limiting factors and symptoms, we evaluated respiratory muscles and quadriceps contractile fatigue, dynamic hyperinflation and symptoms induced by exhaustive high-intensity cycling in COPD patients. Fifteen gold II-III COPD patients (age = 67±6 yr; BMI = 26.6±4.2 kg.m-2) performed constant-load cycling test at 80% of their peak workload until exhaustion (9.3±2.4 min). Before exercise and at exhaustion, potentiated twitch quadriceps strength (Qtw), transdiaphragmatic (Pdi,tw) and gastric (Pga,tw) pressures were evoked by femoral nerve, cervical and thoracic magnetic stimulation, respectively. Changes in operational lung volumes during exercise were assessed via repetitive inspiratory capacity (IC) measurements. Dyspnoea and leg discomfort were measured on visual analog scale. At exhaustion, Qtw (-33±15%, >15% reduction observed in all patients but two) and Pdi,tw (-20±15%, >15% reduction in 6 patients) were significantly reduced (P<0.05) but not Pga,tw (-6±10%, >15% reduction in 3 patients). Percentage reduction in Qtw correlated with the percentage reduction in Pdi,tw (r=0.66; P<0.05). Percentage reductions in Pdi,tw and Pga,tw negatively correlated with the reduction in IC at exhaustion (r=-0.56 and r=-0.62, respectively; P<0.05). Neither dyspnea nor leg discomfort correlated with the amount of muscle fatigue. In conclusion, high-intensity exercise induces quadriceps, diaphragm and less frequently abdominal contractile fatigue in this group of COPD patients. In addition, the rise in end-expiratory lung volume and diaphragm flattening associated with dynamic hyperinflation in COPD might limit the development of abdominal and diaphragm muscle fatigue. This study underlines that both respiratory and quadriceps fatigue should be considered to understand the complex interplay of factors leading to exercise intolerance in COPD patients. PMID:24324843

Bachasson, Damien; Wuyam, Bernard; Pepin, Jean-Louis; Tamisier, Renaud; Levy, Patrick; Verges, Samuel

2013-01-01

59

Quadriceps Tendon Rupture due to Postepileptic Convulsion  

PubMed Central

We present a case of quadriceps tendon (QT) rupture. QT ruptures can occur in all ages. The cause is mostly traumatic in origin. Spontaneous ruptures that are thought to result from predisposing conditions are rare. Post-convulsion QT ruptures lacking traumas in their history can be overlooked in clinical examinations. This should be born in mind by the attending physician, as early diagnosis and treatment of the condition can lead to satisfactory outcomes. PMID:24944977

Erkut, Adem; Guvercin, Yilmaz; Sahin, Rifat; Keskin, Davut

2014-01-01

60

A Study on the Differences of Quadriceps Femoris Activities by Knee Alignment during Isometric Contraction.  

PubMed

[Purpose] This study attempted to identify how genu varum or valgum affects the electromyographic activities of the vastus medialis, vastus lateralis, and rectus femoris during knee isometric contraction. [Subjects] Fifty-two healthy young adults were enrolled in this study. They were enrolled and classified into three groups by knee alignment conditions: the genu varum, genu valgum, and control groups. [Methods] The electromyographic activity ratio of the vastus medialis to the vastus lateralis and rectus femoris were calculated using the percentage of maximum voluntary contraction. The participants contracted their quadriceps during isometric contraction at 30 and 60° of knee flexion. [Results] The genu varum group had more activity in the vastus medialis than in the vastus lateralis and rectus femoris, whereas the genu valgum group had more activity in the vastus lateralis and rectus femoris than in the vastus medialis. There was a significant difference in the muscle activity ratio between the vastus medialis and vastus lateralis by angle of knee flexion degree only in the genu valgum. There were no significant differences in any of the three groups in terms of the muscle activity ratio of the vastus medialis to the rectus femoris by angle of knee flexion. [Conclusion] The quadriceps femoris was used for different strategies according to knee alignment during isometric contraction at 30 and 60°. This study suggests that rehabilitation training programs used to strengthen the quadriceps should consider the knee alignment conditions of the target subjects. PMID:25435677

Park, Seol; Ko, Yu-Min; Jang, Gwon-Uk; Hwang, Yoon-Tae; Park, Ji-Won

2014-11-01

61

Randomized controlled pilot study of neuromuscular electrical stimulation of the quadriceps in patients with non-small cell lung cancer.  

PubMed

Patients with lung cancer experience muscle wasting and weakness. Therapeutic exercise may be beneficial but is not always practical. An alternative approach may be neuromuscular electrical stimulation (NMES) of the quadriceps muscles, but this has not been formally examined in patients with cancer. Thus, we have undertaken this pilot study to assess feasibility and inform the design of future studies. Sixteen patients were randomized to receive usual care (control group) or usual care plus NMES for four weeks. NMES consisted of daily stimulation to both thighs for up to 30minutes (frequency 50Hz, "on" cycle 11%-25%). Adherence was assessed by a self-report diary and a semistructured evaluation form. Quadriceps muscle strength, exercise endurance, and free-living physical activity were assessed using a Cybex NORM dynamometer, an endurance shuttle walk test, and an ActivPAL accelerometer (mean daily step count), respectively. Changes in outcome from baseline were compared between groups by mean differences and their 95% confidence intervals using independent t-test (P=0.05). Median (range) adherence to the program was 80% (69%-100%). All patients found the NMES device easy to use. Changes in outcome favored the NMES group, with mean differences of 9.4 Nm (21%) in quadriceps muscle strength, 768 steps (15%) in free-living activity, and 138 m (8%) in exercise endurance, but none of the differences were statistically significant. In conclusion, NMES warrants further study in patients with lung cancer. PMID:19748761

Maddocks, Matthew; Lewis, Mary; Chauhan, Alpna; Manderson, Cathann; Hocknell, Joanna; Wilcock, Andrew

2009-12-01

62

Pain and Effusion and Quadriceps Activation and Strength  

PubMed Central

Context: Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive. Objective: To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction. Design: Crossover study. Setting: University research laboratory. Patients or Other Participants: Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers. Intervention(s): All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee. Main Outcome Measure(s): Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced. Results: Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05). Conclusions: Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high. PMID:23672382

Palmieri-Smith, Riann M.; Villwock, Mark; Downie, Brian; Hecht, Garin; Zernicke, Ron

2013-01-01

63

Development and delivery of an exercise intervention for rheumatoid arthritis: Strengthening and stretching for rheumatoid arthritis of the hand (SARAH) trial  

Microsoft Academic Search

This paper describes the development and implementation of a hand exercise intervention for rheumatoid arthritis (RA) as part of a large multi-centred randomised controlled trial in a UK National Health Service (NHS) setting. Participants are eligible if diagnosed with RA according to American College of Rheumatology criteria, have a history of disease activity, functional deficit or impairment in the hand

P. J. Heine; M. A. Williams; E. Williamson; C. Bridle; J. Adams; A. O’Brien; D. Evans; S. E. Lamb

64

J Clin Endocrinol Metab. Author manuscript Exercise restores skeletal muscle glucose delivery but not  

E-print Network

; administration & dosage ; metabolism ; Humans ; Insulin ; administration & dosage ; metabolism ; Male ; Models ; Positron-Emission Tomography ; Quadriceps Muscle ; blood supply ; metabolism ; radionuclide imaging synergistic increasing effects on glucose uptake .[3] Exercise strongly promotes blood flow and glucose uptake

Paris-Sud XI, Université de

65

[Glomus tumor in the quadriceps ligament: a case report].  

PubMed

We report a very rare localization of glomus tumor: the quadriceps ligament. The clinical diagnosis in this 19-year-old male patient was difficult. The final diagnosis was established at pathology examination of the surgical resection specimen. Resection provided cure. A review of the literature confirms that the quadriceps is a very rare localization of glomus tumor, no other cases have been reported previously. PMID:15976672

Wahbi, S; Belkourchia, E; Bouhouch, A; Elkharrazi, M; Moustaine, M R; Elmanouar, M

2005-05-01

66

Diagnosis and management of quadriceps strains and contusions  

Microsoft Academic Search

Injuries to the quadriceps muscle group occur frequently in sports and athletic activities. Muscle strains and contusions\\u000a constitute the majority of these injuries. The clinical presentation and assessment of quadriceps strains and contusions are\\u000a reviewed along with discussion of appropriate imaging used in diagnosis. Treatment protocols for acute injuries are reviewed\\u000a including rehabilitation techniques frequently utilized during recovery. Special consideration

Joel M. Kary

2010-01-01

67

Static vs. Dynamic Acute Stretching Effect on Quadriceps Muscle Activity during Soccer Instep Kicking.  

PubMed

The purpose of this study was to compare the effects of static and dynamic stretching on quadriceps muscle activation during maximal soccer instep kicking. The kicking motion of twelve male college soccer players (body height: 174.66 ± 5.01 cm; body mass: 72.83 ± 4.83 kg; age: 18.83 ± 0.75 years) was captured using six synchronized high-speed infra-red cameras whilst electromyography (EMG) signals from vastus medialis (VM), lateralis (VL) and rectus femoris (RF) were recorded before and after static or dynamic stretching. Analysis of variance designs showed a higher increase in knee extension angular velocity (9.65% vs. -1.45%, p < 0.001), RF (37.5% vs. -8.33%, p < 0.001), VM (12% vs. -12%, p < 0.018), and VL EMG activity (20% vs. -6.67%, p < 0.001) after dynamic stretching exercises. Based on these results, it could be suggested that dynamic stretching is probably more effective in increasing quadriceps muscle activity and knee extension angular velocity during the final swing phase of a maximal soccer instep kick than static stretching. PMID:24511339

Amiri-Khorasani, Mohammadtaghi; Kellis, Eleftherios

2013-12-18

68

Effectiveness of Injury Prevention Programs on Developing Quadriceps and Hamstrings Strength of Young Male Professional Soccer Players  

PubMed Central

Muscular strength is an important factor which is crucial for performance and injury prevention in most sports. The purpose of this study was to evaluate the effects of the FIFA’s Medical Assessment and Research Centre 11+ and HarmoKnee injury prevention programs on knee strength of young professional male soccer players. Thirty-six soccer players (age: 18.9 ± 1.4 years) were divided equally into three groups; the 11+, HarmoKnee and control groups. The programs were performed for 24 sessions. Hamstring and quadriceps strength was measured using the Biodex System 3 at 30°, 60° and 90° of knee flexion. The 11+ increased quadriceps strength in the dominant leg by 19.7% and 47.8% at 60°and 90° knee flexion, respectively, and in the non-dominant leg by 16%, 35.3% and 78.1 % at 30°, 60° and 90° knee flexion, respectively. The HarmoKnee group, however, showed increased quadriceps strength only at 90° i.e., by 85.7% in the dominant leg and 73.8% in the non-dominant leg. As for hamstring strength, only the 11+ group demonstrated an increment by 24.8% and 19.8% at 30° and 60° knee flexion in the dominant leg, and in the non-dominant leg, by 28.7% and 13.7% at 30° and 60° knee flexion, respectively. In conclusion, both warm-up programs improve quadriceps strength. The 11+ demonstrated improvement in hamstring strength while the HarmoKnee program did not indicate any improvement. We suggest adding eccentric hamstring components such as Nordic hamstring exercise to the HarmoKnee program in order to enhance hamstring strength. PMID:24511347

Daneshjoo, Abdolhamid; Rahnama, Nader; Mokhtar, Abdul Halim; Yusof, Ashril

2013-01-01

69

Optimal stimulation parameters to detect deficits in quadriceps voluntary activation.  

PubMed

The purpose of this study was to determine optimal stimulation parameters and calculation methods to estimate quadriceps voluntary activation while minimizing participant discomfort. Twelve healthy adults (8 men and 4 women; mean ± SD, age = 36.8 ± 15.6 years, weight = 76.1 ± 12.9 kg, height = 170.2 ± 8.6 cm). Repeated maximal volitional isometric contractions (MVIC) were performed while imposing 4 stimulation combinations (10 or 2 pulses; 400 or 200 V; and variable or standardized current) with the quadriceps in a relaxed state (resting twitch [RT]) and during an MVIC. Quadriceps activation was quantified by calculating the central activation ratio and the percent activation. Discomfort was quantified using the visual analog scale. When comparing calculation methods between the same stimulation parameters, the central activation ratio calculation method produced quadriceps activation values that were significantly greater (p < 0.009) than those derived using the percent activation calculation method. The doublet pulse stimulus produced less discomfort during the RT (p < 0.04) and MVIC (p < 0.001) when compared with all other combinations using a train of stimuli (10 pulses). Correlations for all estimates of quadriceps activation were strong (r = 0.85-0.99, p < 0.001). A doublet pulse stimulus produced discomfort levels that were over 50% lower than a 10-pulse train of stimuli and correlated well (r > 0.88) with activation levels obtained with a 10-pulse train of stimuli. Therefore, the use of a doublet pulse stimulus provides quadriceps activation information equivalent to other methods while minimizing participant discomfort. PMID:23669820

Grindstaff, Terry L; Threlkeld, A Joseph

2014-02-01

70

Effects of Open and Closed Kinetic Chains of Sling Exercise Therapy on the Muscle Activity of the Vastus Medialis Oblique and Vastus Lateralis  

PubMed Central

[Purpose] The muscle strength of the quadriceps muscle is critical in patellofemoral pain syndrome. The quadriceps muscle supplies the power for dynamic patellar movement, and the vastus medialis oblique (VMO) and vastus lateralis (VL) enable the patella to stabilize during tracking. We followed the theories about open and closed kinetic chain exercises to design two exercises, sling open chain knee extension (SOCKE) exercise and sling closed chain knee extension (SCCKE) exercise. The purpose of our study was to research the changes in quadriceps muscle activity during both exercises. [Methods] Electromyographic analysis was used to explore the different effects of the two exercises. The MVC% was calculated for the VMO and VL during exercise for analysis. [Results] We found that the mean MVC% values of the VMO and VL during the SOCKE exercise were higher than those during the SCCKE exercise. The ratio of the VMO to VL was 1.0 ± 0.19 during the SOCKE exercise and 1.11 ± 0.15 during the SCCKE exercise. [Conclusions] The SOCKE exercise is targeted at quadriceps muscle training and has a recruitment effect on the VMO. The beneficial effect of the SOCKE exercise is better than that of the SCCKE exercise. PMID:25276016

Chang, Wen-Dien; Huang, Wei-Syuan; Lee, Chia-Lun; Lin, Hung-Yu; Lai, Ping-Tung

2014-01-01

71

Quantification method affects estimates of voluntary quadriceps activation.  

PubMed

The aim of this study was to investigate the effect of quantification method on estimates of voluntary quadriceps muscle activation. Twenty-two people with no history of serious lower extremity injuries underwent voluntary quadriceps activation testing at 60 degrees of knee flexion. Estimates of quadriceps activation were derived with: (1) a formula based on the interpolated twitch technique (ITT); (2) the central activation ratio (CAR); and (3) a modified central activation ratio. Predictive equations were developed that describe the relationships between the three methods. Significant differences (P < 0.001) were observed between the estimates of voluntary quadriceps muscle activation obtained using the three methods (ITT percent activation = 93.0 +/- 6.4%, CAR = 95.9 +/- 3.8%, modified CAR = 98.5 +/- 4.1%). Excellent correlation (r = 0.995) was observed between ITT-based percent activation and the CAR method. The associations between these methods and the modified CAR approach were weaker. Quantification method affects activation estimates. The equations developed will assist scientists in accurately comparing the results of studies that use different methods of quantifying activation. PMID:20229578

Krishnan, Chandramouli; Williams, Glenn N

2010-06-01

72

Quadriceps Activation Following Knee Injuries: A Systematic Review  

PubMed Central

Abstract Context: Arthrogenic muscle inhibition is an important underlying factor in persistent quadriceps muscle weakness after knee injury or surgery. Objective: To determine the magnitude and prevalence of volitional quadriceps activation deficits after knee injury. Data Sources: Web of Science database. Study Selection: Eligible studies involved human participants and measured quadriceps activation using either twitch interpolation or burst superimposition on patients with knee injuries or surgeries such as anterior cruciate ligament deficiency (ACLd), anterior cruciate ligament reconstruction (ACLr), and anterior knee pain (AKP). Data Extraction: Means, measures of variability, and prevalence of quadriceps activation (QA) failure (<95%) were recorded for experiments involving ACLd (10), ACLr (5), and AKP (3). Data Synthesis: A total of 21 data sets from 18 studies were initially identified. Data from 3 studies (1 paper reporting data for both ACLd and ACLr, 1 on AKP, and the postarthroscopy paper) were excluded from the primary analyses because only graphical data were reported. Of the remaining 17 data sets (from 15 studies), weighted mean QA in 352 ACLd patients was 87.3% on the involved side, 89.1% on the uninvolved side, and 91% in control participants. The QA failure prevalence ranged from 0% to 100%. Weighted mean QA in 99 total ACLr patients was 89.2% on the involved side, 84% on the uninvolved side, and 98.5% for the control group, with prevalence ranging from 0% to 71%. Thirty-eight patients with AKP averaged 78.6% on the involved side and 77.7% on the contralateral side. Bilateral QA failure was commonly reported in patients. Conclusions: Quadriceps activation failure is common in patients with ACLd, ACLr, and AKP and is often observed bilaterally. PMID:20064053

Hart, Joseph M.; Pietrosimone, Brian; Hertel, Jay; Ingersoll, Christopher D.

2010-01-01

73

MODIFIED CONCEPT 2 TM ROWING MACHINE WITH MANUAL FES CONTROLLER FOR TOTAL BODY EXERCISE IN PARAPLEGIA  

Microsoft Academic Search

Concept 2 indoor rowing machine (Concept 2 Inc., USA), an exercise and training machine for able-bodied population, was modified for total body exercise in paraplegia. A new seating system provides trunk stability and constrains the leg motion to the sagittal plane. A 4-channel electrical stimulator activates the quadriceps and hamstrings in drive and recovery phases of rowing cycle. Force sensing

Rahman Davoodi; Brian Andrews; Garry Wheeler

2001-01-01

74

Eccentric loading for Achilles tendinopathy — strengthening or stretching?  

Microsoft Academic Search

The prescription of eccentric loading is considered as a mainstay of non-operative rehabilitation programmes for mid-substance chronic Achilles tendinopathy. Such exercises have some degree of clinical utility in comparison with concentric training and are often referred to as a strengthening programme. Yet the dose parameters of the eccentric loading do not reflect an optimal strengthening programme and specifically avoid the

G T Allison; C Purdam

2009-01-01

75

Fatigue and rapid hamstring/quadriceps force capacity in professional soccer players.  

PubMed

The aim of this study was to investigate the effect of fatigue induced by an exhaustive laboratory-based soccer-specific exercise on different hamstrings/quadriceps (H:Q) ratios of soccer players. Twenty-two male professional soccer players (23·1 ± 3·4 year) performed maximal eccentric (ecc) and concentric (con) contractions for knee extensors (KE) and flexors (KF) at 60° s(-1) and 180° s(-1) to assess conventional (H(con) :Q(con)) and functional (H(ecc) :Q(con)) ratios. Additionally, they performed maximal voluntary isometric contraction for KE and KF, from which the maximal muscle strength, rate of force development (RFD) and RFD H:Q strength ratio (RFDH:Q) were extracted. Thereafter, subjects were performed an exhaustive laboratory-based soccer-specific exercise and a posttest similar to the pretest. There was significant reduction in H(con) :Q(con) (0·60 ± 0·06 versus 0·58 ± 0·06, P<0·05) and in H(ecc) :Q(con) (1·29 ± 0·2 versus 1·16 ± 0·2, P<0·01) after the soccer-specific exercise. However, no significant difference between Pre and Post exercise conditions was found for RFDH:Q at 0-50 (0·53 ± 0·23 versus 0·57 ± 0·24, P>0·05) and 0-100 ms (0·53 ± 0·17 versus 0·55 ± 0·17, P>0·05). In conclusion, H:Q strength ratios based on peak force values are more affected by fatigue than RFDH:Q obtained during early contraction phase. Thus, fatigue induced by soccer-specific intermittent protocol seems not reduce the potential for knee joint stabilization during the initial phase of voluntary muscle contraction. PMID:23216761

Greco, Camila C; da Silva, Wendell L; Camarda, Sérgio R A; Denadai, Benedito S

2013-01-01

76

Quadriceps Activation Failure After Anterior Cruciate Ligament Rupture Is Not Mediated by Knee Joint Effusion  

PubMed Central

STUDY DESIGN Descriptive prospective cohort study. OBJECTIVES To investigate the relationships between knee joint effusion, quadriceps activation, and quadriceps strength. These relationships may help clinicians better identify impaired quadriceps activation. BACKGROUND After anterior cruciate ligament (ACL) injury, the involved quadriceps may demonstrate weakness. Experimental data have shown that quadriceps activation and strength may be directly mediated by intracapsular joint pressure created by saline injection. An inverse relationship between quadriceps activation and the amount of saline injected has been reported. This association has not been demonstrated for traumatic effusion. We hypothesized that traumatic joint effusion due to ACL rupture and postinjury quadriceps strength would correlate well with quadriceps activation, allowing clinicians to use effusion and strength measurement as a surrogate for electrophysiological assessment of quadriceps activation. METHODS Prospective data were collected on 188 patients within 100 days of ACL injury (average, 27 days) referred from a single surgeon. A complete clinical evaluation of the knee was performed, including ligamentous assessment and assessment of range of motion and effusion. Quadriceps function was electrophysiologically assessed using maximal volitional isometric contraction and burst superimposition techniques to quantify both strength and activation. RESULTS Effusion grade did not correlate with quadriceps central activation ratio (CAR) (zero effusion: mean ± SD CAR, 93.5% ± 5.8%; trace effusion: CAR, 93.8% ± 9.5%; 1+ effusion: CAR, 94.0% ± 7.5%; 2+/3+ effusion: CAR, 90.6% ± 11.1%). These values are lower than normative data from healthy subjects (CAR, 98% ± 3%). CONCLUSION Joint effusion after ACL injury does not directly mediate quadriceps activation failure seen after injury. Therefore, it should not be used as a clinical substitute for electrophysiological assessment of quadriceps activation. Patients presenting to physical therapy after ACL injury should be treated with high-intensity neuromuscular electrical stimulation to help normalize this activation. PMID:22523081

LYNCH, ANDREW D.; LOGERSTEDT, DAVID S.; AXE, MICHAEL J.; SNYDER-MACKLER, LYNN

2013-01-01

77

Pre-synaptic modulation of quadriceps arthrogenic muscle inhibition.  

PubMed

Arthrogenic muscle inhibition (AMI) impedes rehabilitation following knee joint injury by preventing activation of the quadriceps. AMI has been attributed to neuronal reflex activity in which altered afferent input originating from the injured joint results in a diminished efferent motor drive to the quadriceps muscles. Beginning to understand the mechanisms responsible for muscle inhibition following joint injury is vital to control or eliminate this phenomenon. Therefore, the purpose of this investigation is to determine if quadriceps AMI is mediated by a presynaptic regulatory mechanism. Eight adults participated in two sessions: in one session their knee was injected with saline and in the other session it was not. The maximum Hoffmann reflex (H-reflex), M-wave, reflex activation history, plasma epinephrine, and norepinephrine were recorded at: baseline, post needle stick, post lidocaine, and 25 and 45 min post effusion. Measures for the control condition were matched to the effusion condition. The percent of the unconditioned reflex amplitude for reflex activation history and the maximum H-reflex were decreased at 25 and 45 min post effusion as compared to measures taken at baseline, post needle stick, and post lidocaine (P<0.05). No differences were noted for the maximum M-wave or plasma epinephrine and norepinephrine levels in either the effusion or noneffusion admission (P>0.05). No differences were detected at any time interval for any measure during the control admission (P>0.05). Quadriceps AMI elicited via an experimental knee joint effusion is, at least in part, mediated by a presynaptic mechanism. PMID:15685462

Palmieri, Riann M; Weltman, Arthur; Edwards, Jeffrey E; Tom, James A; Saliba, Ethan N; Mistry, Danny J; Ingersoll, Christopher D

2005-07-01

78

Assessing contractile ability of the quadriceps muscle using ultrasound imaging.  

PubMed

Muscle dimension changes on ultrasound imaging (USI) indicate contractile activity. Quadriceps force and rectus femoris (RF) dimensions were examined to assess USI for estimating contraction level. In 15 healthy males, mean age 24.8 years, isometric quadriceps force was measured in 90° knee flexion during submaximal and maximal voluntary contractions (MVCs) and at MVC in extension. Mid-thigh cross-sectional area (CSA), depth and width, and surface electromyography (EMG) of RF were recorded. Muscle width decreased curvilinearly as both force and EMG increased. At MVC, width was 3.2 ± 0.5 cm, 25% smaller than at rest (4.4 ± 0.7 cm), and similar to MVC in extension (-23%). CSA decreased linearly to -18% at MVC. RF thickness increased by only 10% (at 30% to MVC). Similar width changes at MVC in flexion and extension indicate the clinical potential of USI for assessing quadriceps contractility. Sensitivity is limited to assessing strength to within 25% of MVC in young males. PMID:20665511

Delaney, Sinead; Worsley, Peter; Warner, Martin; Taylor, Mark; Stokes, Maria

2010-10-01

79

Effects of Kinesiology Taping on Repositioning Error of the Knee Joint after Quadriceps Muscle Fatigue  

PubMed Central

[Purpose] The purpose of this study was to identify the effects of kinesiology taping on repositioning error of the knee joint after quadriceps muscle fatigue. [Subjects] Thirty healthy adults with no orthopaedic or neurological problems participated in this study. [Methods] The repositioning error of the knee joint was measured using a digital goniometer when the subjects extended their dominant-side knee to a random target angle (30°, 45°, or 60°) with their eyes closed, before and after a quadriceps muscle fatigue protocol, and after application of kinesiology tape. [Results] We found that repositioning errors of the dominant-side knee joint increased after quadriceps fatigue compared with no-fatigue conditions. However, kinesiology taping of the quadriceps muscle and patella after quadriceps fatigue significantly decreased repositioning errors of the knee joint. [Conclusion] These results suggest that quadriceps fatigue increases the repositioning error of the knee joint, whereas application of kinesiology tape decreases fatigue-induced joint repositioning error. PMID:25013297

Han, Jin Tae; Lee, Jung-hoon

2014-01-01

80

Effects of kinesiology taping on repositioning error of the knee joint after quadriceps muscle fatigue.  

PubMed

[Purpose] The purpose of this study was to identify the effects of kinesiology taping on repositioning error of the knee joint after quadriceps muscle fatigue. [Subjects] Thirty healthy adults with no orthopaedic or neurological problems participated in this study. [Methods] The repositioning error of the knee joint was measured using a digital goniometer when the subjects extended their dominant-side knee to a random target angle (30°, 45°, or 60°) with their eyes closed, before and after a quadriceps muscle fatigue protocol, and after application of kinesiology tape. [Results] We found that repositioning errors of the dominant-side knee joint increased after quadriceps fatigue compared with no-fatigue conditions. However, kinesiology taping of the quadriceps muscle and patella after quadriceps fatigue significantly decreased repositioning errors of the knee joint. [Conclusion] These results suggest that quadriceps fatigue increases the repositioning error of the knee joint, whereas application of kinesiology tape decreases fatigue-induced joint repositioning error. PMID:25013297

Han, Jin Tae; Lee, Jung-Hoon

2014-06-01

81

Quadriceps weakness in knee osteoarthritis: the effect on pain and disability  

Microsoft Academic Search

OBJECTIVES(1) To determine the importance of quadriceps strength, structural change, and psychological status in terms of knee pain in the community. (2) To determine the relative importance of quadriceps function, structural change, and psychological status with respect to disability in subjects with knee pain.METHODS300 men and women with pain and 300 controls without pain (aged 40–79) were seen. Isometric quadriceps

Sheila C O’Reilly; Adrian Jones; Ken R Muir; Michael Doherty

1998-01-01

82

Arthrogenic quadriceps inhibition and rehabilitation of patients with extensive traumatic knee injuries.  

PubMed

1. The relationship between joint damage, quadriceps weakness and arthrogenic muscle inhibition was investigated in eight patients who had sustained extensive traumatic knee injury. Isometric and isokinetic quadriceps and hamstring voluntary strength, and quadriceps arthrogenic muscle inhibition during isometric contractions, were measured before and after 4 weeks (approximately 100 h) of intensive rehabilitation. 2. Compared with the uninjured leg, before rehabilitation the injured leg had larger amounts of quadriceps arthrogenic muscle inhibition (P < 0.025), quadriceps (P < 0.0001) and hamstring (P < 0.0001) weakness and severe functional joint instability. There was a negative correlation between the amount of arthrogenic muscle inhibition and quadriceps voluntary contraction force (P < 0.025). 3. After rehabilitation in the injured leg there were small hamstring strength increases (P < 0.05-0.025), but no overall significant quadricep strength increase. Arthrogenic muscle inhibition was statistically unchanged. Severe functional joint instability was still reported by all patients. 4. Previous studies have shown that minimal joint damage evokes relatively less arthrogenic muscle inhibition that does not impede rehabilitation. These data indicate that greater joint damage is associated with greater arthrogenic muscle inhibition, quadriceps weakness and joint instability. Furthermore, intensive rehabilitation had little affect on either quadriceps arthrogenic muscle inhibition or atrophy. PMID:8156741

Hurley, M V; Jones, D W; Newham, D J

1994-03-01

83

Lateral Patellofemoral Ligament Reconstruction Using a Quadriceps Tendon Graft  

PubMed Central

Medial patellar subluxation (MPS) is normally described after a lateral retinacular release. However, isolated MPS in the absence of a previous lateral release does occur. This type of patellar instability is often overlooked, and a high index of suspicion is needed for appropriate diagnosis and treatment. This report describes a technique developed in response to episodes of isolated MPS. The technique uses a partial-thickness graft from the quadriceps tendon to reconstruct the lateral patellofemoral ligament and provide stability to the lateral side of the patella. PMID:25264506

Saper, Michael G.; Shneider, David A.

2014-01-01

84

Electrode Type and Placement Configuration for Quadriceps Activation Evaluation  

PubMed Central

Context: The ability to accurately estimate quadriceps voluntary activation is an important tool for assessing neuromuscular function after a variety of knee injuries. Different techniques have been used to assess quadriceps volitional activation, including various stimulating electrode types and electrode configurations, yet the optimal electrode types and configurations for depolarizing motor units in the attempt to assess muscle activation are unknown. Objective: To determine whether stimulating electrode type and configuration affect quadriceps central activation ratio (CAR) and percentage-of-activation measurements in healthy participants. Design: Crossover study. Setting: Research laboratory. Patients and Other Participants: Twenty participants (13 men, 7 women; age = 26 ± 5.3 years, height = 173.85 ± 7.3 cm, mass = 77.37 ± 16 kg) volunteered. Intervention(s): All participants performed 4 counter-balanced muscle activation tests incorporating 2 different electrode types (self-adhesive, carbon-impregnated) and 2 electrode configurations (vastus, rectus). Main Outcome Measure(s): Quadriceps activation was calculated with the CAR and percentage-of-activation equations, which were derived from superimposed burst and resting torque measurements. Results: No differences were found between conditions for CAR and percentage-of-activation measurements, whereas resting twitch torque was higher in the rectus configuration for both self-adhesive (216 ± 66.98 Nm) and carbon-impregnated (209.1 ± 68.22 Nm) electrodes than in the vastus configuration (209.5 ± 65.5 Nm and 204 ± 62.7 Nm, respectively) for these electrode types (F1,19 = 4.87, P = .04). In addition, resting twitch torque was greater for both electrode configurations with self-adhesive electrodes than with carbon-impregnated electrodes (F1,19 = 9.33, P = .007). Bland-Altman plots revealed acceptable mean differences for agreement between electrode type and configuration for CAR and percentage of activation, but limits of agreement were wide. Conclusions: Although these electrode configurations and types might not necessarily be able to be used interchangeably, differences in electrode type and configuration did not seem to affect CAR and percentage-of-activation outcome measures. PMID:22488187

Pietrosimone, Brian G.; Selkow, Noelle M.; Ingersoll, Christopher D.; Hart, Joseph M.; Saliba, Susan A.

2011-01-01

85

Anterior-posterior and rotational displacement of the tibia elicited by quadriceps contraction  

Microsoft Academic Search

The anterior-posterior displacement and rotation of the tibia elicited by isolated loading of the quadriceps mus cle was determined as a function of joint angle and muscle load using a computerized radiographic tech nique. Data collected from 12 fresh-frozen cadaveric knees demonstrated that quadriceps contraction can result in significant (<7 mm) anterior displacement of the tibia in the range of

Shunji Hirokawa; Moshe Solomonow; Yun Lu; Zong-Ping Lou; Robert DAmbrosia

1992-01-01

86

Quadriceps tendon allografts as an alternative to Achilles tendon allografts: a biomechanical comparison.  

PubMed

Quadriceps tendon with a patellar bone block may be a viable alternative to Achilles tendon for anterior cruciate ligament reconstruction (ACL-R) if it is, at a minimum, a biomechanically equivalent graft. The objective of this study was to directly compare the biomechanical properties of quadriceps tendon and Achilles tendon allografts. Quadriceps and Achilles tendon pairs from nine research-consented donors were tested. All specimens were processed to reduce bioburden and terminally sterilized by gamma irradiation. Specimens were subjected to a three phase uniaxial tension test performed in a custom environmental chamber to maintain the specimens at a physiologic temperature (37 ± 2 °C) and misted with a 0.9 % NaCl solution. There were no statistical differences in seven of eight structural and mechanical between the two tendon types. Quadriceps tendons exhibited a significantly higher displacement at maximum load and significantly lower stiffness than Achilles tendons. The results of this study indicated a biomechanical equivalence of aseptically processed, terminally sterilized quadriceps tendon grafts with bone block to Achilles tendon grafts with bone block. The significantly higher displacement at maximum load, and lower stiffness observed for quadriceps tendons may be related to the failure mode. Achilles tendons had a higher bone avulsion rate than quadriceps tendons (86 % compared to 12 %, respectively). This was likely due to observed differences in bone block density between the two tendon types. This research supports the use of quadriceps tendon allografts in lieu of Achilles tendon allografts for ACL-R. PMID:24414293

Mabe, Isaac; Hunter, Shawn

2014-12-01

87

Exercise May Cut Fall Risk for Some Parkinson's Patients  

MedlinePLUS

... 2014 Related MedlinePlus Pages Exercise and Physical Fitness Parkinson's Disease WEDNESDAY, Dec. 31, 2014 (HealthDay News) -- Exercises that ... and leg strengthening may help some people with Parkinson's disease avoid falls, according to a new clinical trial. ...

88

Expand and Strengthen Interdisciplinary  

E-print Network

Workforce Readiness Adapt to Evolving Educational Models and Support Innovation Establish a Culture of Best to Evolving Educational Models and Support Innovation Establish a Culture of Best Practices Strengthen Program Partnerships Define/Align Benefits and Expectations of Key Partnerships Strengthen Customized Approach

Cui, Yan

89

Open versus closed kinetic chain exercise: issues in rehabilitation after anterior cruciate ligament reconstructive surgery.  

PubMed

What has been called "closed kinetic chain" (CKC) exercise has become popular in the last 5 to 10 years for use after anterior cruciate ligament (ACL) reconstructive surgery. Closed kinetic chain exercises appear to have gained popularity over more traditionally used open kinetic chain (OKC) exercises because many clinicians believe that CKC exercises are safer and more functional. These clinicians also contend that CKC exercise is equally effective as OKC exercise in restoring quadriceps femoris muscle force production following ACL reconstructive surgery. The purpose of this clinical perspective is to examine the evidence concerning OKC and CKC training after ACL reconstructive surgery with regard to these issues and discuss how physical therapists can best apply this knowledge in clinical practice. Based on the review of data, it does not appear that clinicians should completely abandon more traditional OKC exercises and replace them with CKC exercises in postoperative ACL reconstruction rehabilitation programs. Both types of exercise apparently can be modified to minimize (1) the risk of applying excessive strain on the ACL graft and (2) the risk of excessive patellofemoral joint stress. Depending on the functional goals of the patient, both OKC and CKC exercises may be appropriate for simulating functional activities. When improvement in quadriceps femoris muscle function is an essential treatment goal, therapists may need to combine OKC exercises with CKC exercises to provide optimal training stimuli. Suggestions for further research are discussed. [Fitzgerald GK. Open versus closed kinetic chain exercise: issues in rehabilitation after anterior cruciate ligament reconstructive surgery. PMID:9413453

Fitzgerald, G K

1997-12-01

90

Isometric Quadriceps Strength in Women with Mild, Moderate, and Severe Knee Osteoarthritis  

PubMed Central

Objective Quadriceps weakness is a common clinical sign in persons with moderate-to-severe osteoarthritis and results in physical disability; however, minimal data exist to establish whether quadriceps weakness is present in early stages of the disease. Therefore, our purpose was to determine whether quadriceps weakness was present in persons with early radiographic and cartilaginous evidence of osteoarthritis. Further, we sought to determine whether quadriceps strength decreases as osteoarthritis severity increases. Design Three hundred forty-eight women completed radiologic and magnetic resonance imaging evaluation, in addition to strength testing. Anterior-posterior radiographs were graded for tibiofemoral osteoarthritis severity using the Kellgren-Lawrence scale. Scans from magnetic resonance imaging were used to assess medial tibiofemoral and patellar cartilage based on a modification of the Noyes scale. The peak knee extension torque recorded was used to represent strength. Results Quadriceps strength (Nm/kg) was 22% greater in women without radiographic osteoarthritis than in women with osteoarthritis (P < 0.05). Quadriceps strength was also greater in women with Noyes’ medial tibial and femoral cartilage scores of 0 when compared in women with Noyes’ grades 2 and 3–5 (P ? 0.05). Conclusions Women with early evidence of osteoarthritis had less quadriceps strength than women without osteoarthritis as defined by imaging. PMID:20463561

Palmieri-Smith, Riann M.; Thomas, Abbey C.; Karvonen-Gutierrez, Carrie; Sowers, Mary Fran

2012-01-01

91

Relationship Between Intensity of Quadriceps Muscle Neuromuscular Electrical Stimulation and Strength Recovery After Total Knee Arthroplasty  

PubMed Central

Background Neuromuscular electrical stimulation (NMES) can facilitate the recovery of quadriceps muscle strength after total knee arthroplasty (TKA), yet the optimal intensity (dosage) of NMES and its effect on strength after TKA have yet to be determined. Objective The primary objective of this study was to determine whether the intensity of NMES application was related to the recovery of quadriceps muscle strength early after TKA. A secondary objective was to quantify quadriceps muscle fatigue and activation immediately after NMES to guide decisions about the timing of NMES during rehabilitation sessions. Design This study was an observational experimental investigation. Methods Data were collected from 30 people who were 50 to 85 years of age and who received NMES after TKA. These people participated in a randomized controlled trial in which they received either standard rehabilitation or standard rehabilitation plus NMES to the quadriceps muscle to mitigate strength loss. For the NMES intervention group, NMES was applied 2 times per day at the maximal tolerable intensity for 15 contractions beginning 48 hours after surgery over the first 6 weeks after TKA. Neuromuscular electrical stimulation training intensity and quadriceps muscle strength and activation were assessed before surgery and 3.5 and 6.5 weeks after TKA. Results At 3.5 weeks, there was a significant association between NMES training intensity and a change in quadriceps muscle strength (R2=.68) and activation (R2=.22). At 6.5 weeks, NMES training intensity was related to a change in strength (R2=.25) but not to a change in activation (R2=.00). Furthermore, quadriceps muscle fatigue occurred during NMES sessions at 3.5 and 6.5 weeks, whereas quadriceps muscle activation did not change. Limitations Some participants reached the maximal stimulator output during at least 1 treatment session and might have tolerated more stimulation. Conclusions Higher NMES training intensities were associated with greater quadriceps muscle strength and activation after TKA. PMID:22652985

Balter, Jaclyn E.; Wolfe, Pamela; Eckhoff, Donald G.; Schwartz, Robert S.; Schenkman, Margaret; Kohrt, Wendy M.

2012-01-01

92

Relaxation electromechanical delay of the quadriceps during selected movement velocities.  

PubMed

The purpose of this study was to quantify the time between the cessation of EMG activity and cessation of torque production, or relaxation electromechanical delay, (R-EMD) of the quadriceps at three angular movement velocities. A Biodex dynamometer passively moved the right knee of 25 males through a given range at three velocities (10, 60 and 120 degrees per second). Subjects were instructed to actively extend their knees to a visual target, then to immediately relax. Biodex torque and position data, as well as surface EMG from the right Vastus Medialis (VM), Rectus Femoris (RF) and Vastus Lateralis (VL) were sampled simultaneously. EMG cessation was determined when activity fell below a threshold based on the muscle's resting EMG. Torque cessation was determined when the slope of the relaxation curve decreased to 10% of the initial value. R-EMD time for each quadriceps head at each velocity was determined by calculating the difference between these two times. To examine reliability, subjects were retested four days later. Approximately two thirds of the subjects were unable to consistently perform the motor task of abrupt relaxation at some or all of the tested velocities. This variability was ascribed to motor control issues. Average R-EMD times for all subjects, muscle segments and velocities ranged from 249 +/- 68 ms to 276 +/- 51 ms during the first test session, and 239 +/- 46 ms to 300 +/- 59 ms during the second session. These data are important in identification of physiologically meaningful cessation of muscle contraction, and may be beneficial in research studies focusing on the areas of motor control and motor learning, computerized movement analysis, and prediction models for the determination of muscular force from the EMG signal. PMID:8737937

Ferris-Hood, K; Threlkeld, A J; Horn, T S; Shapiro, R

1996-01-01

93

Patellofemoral stressA prospective analysis of exercise treatment in adolescents and adults  

Microsoft Academic Search

Thirty patients, 13 skeletally immature individuals and 17 adults, participated in a prospective study designed to evaluate the effect of isometric quadriceps strength ening exercises on patellofemoral pain. Of the 30 pa tients with anatomically normal lower extremity align ment and no history of previous knee trauma or sur gery, there were 34 knees that had a decrease in peripatellar

Daniel B. ONeill; Lyle J. Micheli; Jon P. Warner

1992-01-01

94

Development of an indoor rowing machine with manual FES controller for total body exercise in paraplegia  

Microsoft Academic Search

Concept 2 indoor rowing machine (Concept 2 Inc., USA) was modified for functional electrical stimulation (FES) rowing exercise in paraplegia. A new seating system provides trunk stability and constrains the leg motion to the sagittal plane. A 4-channel electrical stimulator activates the quadriceps and hamstrings in Drive and Recovery phases of the rowing cycle, respectively. Two force-sensing resistors (FSR) on

Rahman Davoodi; Brian J. Andrews; Garry D. Wheeler; Robert Lederer

2002-01-01

95

Functional plyometric exercises for the throwing athlete.  

PubMed

In this article we provide athletic health care professionals with a variety of functional strengthening exercises to use in improving the muscular strength of the throwing athlete's shoulder. Upper extremity functional plyometric exercise in sport-specific patterns can be an important component of a throwing athlete's rehabilitation. We discuss several plyometric exercises, using the Inertial Exercise System, the Plyo-ball, and the Theraband. Proper use of these exercises can facilitate a safe and progressive rehabilitation program for the injured, throwing athlete. After the athlete has successfully completed the functional plyometric exercises, a throwing progression can be initiated. PMID:16558304

Pezzullo, D J; Karas, S; Irrgang, J J

1995-03-01

96

Contributors to Fatigue Resistance of the Hamstrings and Quadriceps in Cerebral Palsy  

PubMed Central

Background The purpose of this study was to elucidate relationships between quadriceps and hamstrings voluntary muscle fatigue and upper motor lesion impairments in cerebral palsy in order to gain a better understanding of their contribution to the observed fatigue resistance. Methods Seventeen ambulatory subjects with cerebral palsy (mean age: 17.0, SD = 4.8 years) were recruited. Quantitative measures of strength, spasticity, cocontraction, and stiffness for both muscle groups were collected on an isokinetic dynamometer and entered in a factor analysis. The resulting factors were used as independent variables in a multiple regression analysis with quadriceps and hamstrings fatigue as dependent variables. Findings Five independent factors explained 90% of the variance. In order of loadings, higher hamstring cocontraction and spasticity and lower hamstring strength were associated with lower levels of hamstring fatigue. Higher quadriceps cocontraction and lower quadriceps strength were the most predictive of lower levels of quadriceps fatigue. Interpretation Greater motor impairments of the agonist muscle, particularly cocontraction, spasticity, and weakness, were associated with lower rates of muscle fatigue of the same muscle during performance of a voluntary fatigue protocol for the hamstrings and quadriceps. Muscles are highly adaptable; therefore, the results of this study suggest that the observed fatigue resistance may be due to the effect of the primary neural insult on motor unit recruitment and rate modulation or the result of secondary adaptations to spasticity, weakness, or excessive cocontraction. PMID:19264384

Moreau, Noelle G; Li, Li; Geaghan, James P; Damiano, Diane L

2009-01-01

97

Effect of eccentric isokinetic strengthening in the rehabilitation of patients with knee osteoarthritis: Isogo, a randomized trial  

PubMed Central

Background Femorotibial knee osteoarthritis is associated with muscle weakness in the lower limbs, particularly in the quadriceps, which results in disease progression. The interest of having muscular strengthening as part of the therapeutic arsenal for the medical treatment of knee osteoarthritis is now well established. The functional disability induced by knee osteoarthritis manifests itself principally when walking, notably downhill, during which the muscles are called upon to contract eccentrically. We can therefore think that eccentric muscular strengthening could bring a functional benefit that is superior to concentric muscular strengthening. Methods/Design This is a prospective, randomized, bicenter, parallel-group, international study. Eighty patients aged from 40 to 75 years old, suffering from medical-stage knee osteoarthritis, will undertake 6 weeks of isokinetic muscular strengthening. Randomization determines the mode of muscular strengthening: either exclusively eccentric or exclusively concentric. The principal objective is to demonstrate the superiority of the improvement in the quadriceps isokinetic torque after isokinetic muscular strengthening by the eccentric mode compared to the concentric mode. The following parameters are also evaluated: the variations in the level of pain, the parameters of walking (maximum speed over 10 and 200 meters, analysis on a computerized Gaitrite™ treadmill), static equilibrium (on a FUSYO™ force platform), and the functional status of the patient using the Western Ontario and MacMaster Universities osteoarthritis index (WOMAC) questionnaire after the strengthening period and at 6 months. Discussion A better knowledge of the most effective mode of muscular strengthening is needed to optimize the functional benefits to the patients. In case of superiority in terms of efficacy of the eccentric mode, the latter could be given priority in the rehabilitation treatment of knee osteoarthritis patients. Trial registration Clinical trials.gov number: NCT01586130. PMID:24693988

2014-01-01

98

Lumbopelvic Joint Manipulation and Quadriceps Activation of People With Patellofemoral Pain Syndrome  

PubMed Central

Context: Quadriceps weakness and inhibition are impairments associated with patellofemoral pain syndrome (PFPS). Lumbopelvic joint manipulation has been shown to improve quadriceps force output and inhibition, but the duration of the effect is unknown. Objective: To determine whether quadriceps strength and activation are increased and maintained for 1 hour after high-grade or low-grade joint mobilization or manipulation applied at the lumbopelvic region in people with PFPS. Design: Randomized controlled clinical trial. Setting: University laboratory. Patients or Other Participants: Forty-eight people with PFPS (age = 24.6±8.9 years, height = 174.3 ± 11.2 cm, mass = 78.4 ± 16.8 kg) participated. Intervention(s): Participants were randomized to 1 of 3 groups: lumbopelvic joint manipulation (grade V), side-lying lumbar midrange flexion and extension passive range of motion (grade II) for 1 minute, or prone extension on the elbows for 3 minutes. Main Outcome Measure(s): Quadriceps force and activation were measured using the burst superimposition technique during a seated isometric knee extension task. A 2-way repeated-measures analysis of variance was performed to compare changes in quadriceps force and activation among groups over time (before intervention and at 0, 20, 40, and 60 minutes after intervention). Results: We found no differences in quadriceps force output (F5,33,101,18 = 0.65, P = .67) or central activation ratio (F4.84,92.03 = 0.38, P= .86) values among groups after intervention. When groups were pooled, we found differences across time for quadriceps force (F2.66,101.18 = 5.03, P = .004) and activation (F2.42,92.03 = 3.85, P = .02). Quadriceps force was not different at 0 minutes after intervention (t40 = 1.68, P = .10), but it decreased at 20 (t40 = 2.16, P = .04), 40 (t40 = 2.87, P = .01) and 60 (t40 = 3.04, P = .004) minutes after intervention. All groups demonstrated decreased quadriceps activation at 0 minutes after intervention (t40 = 4.17, P <.001), but subsequent measures were not different from preintervention levels (t40 range, 1.53–1.83, P >.09). Conclusions: Interventions directed at the lumbopelvic region did not have immediate effects on quadriceps force output or activation. Muscle fatigue might have contributed to decreased force output and activation over 1 hour of testing. PMID:22488227

Grindstaff, Terry L.; Hertel, Jay; Beazell, James R.; Magrum, Eric M.; Kerrigan, D. Casey; Fan, Xitao; Ingersoll, Christopher D.

2012-01-01

99

Strengthening America's Families.  

ERIC Educational Resources Information Center

Improving parenting practices and the family environment is the most effective, enduring strategy for combating juvenile delinquency. Describes the Office of Juvenile Justice and Delinquency Prevention's Strengthening America's Families Initiative. Highlights several family-focused prevention programs identified as exemplary, explaining how they…

Alvarado, Rose; Kumpfer, Karol

2000-01-01

100

Oxide dispersion strengthened superalloy  

NASA Technical Reports Server (NTRS)

MA6000E alloy is strengthened at high temperatures by dispersion of yttrium oxide. Strength properties are about twice those of conventional nickel base alloys. Good thermal fatigue, intermediate temperature strength, and good oxidation resistance give alloy unique combination of benefits. Application in aircraft gas turbine is improved.

Glasgow, T. K.; Kim, Y. G.; Curwick, L. R.; Merrick, H. F.

1981-01-01

101

Light Rail Transit Strengthening  

E-print Network

Light Rail Transit Improving mobility Easing congestion Strengthening our communities Central Corridor Communicating to the Public During Major Construction May 25, 2011 #12;2 Light Rail Transit;Light Rail Transit Central Corridor Route and Stations 3 · 18 new stations · 9.8 miles of new double

Minnesota, University of

102

Isokinetic Hamstrings:Quadriceps Ratios in Intercollegiate Athletes  

PubMed Central

Objective: To compare the differences in the concentric hamstrings:quadriceps (H:Q) ratio among athletes in different sports at 3 velocities. Design and Setting: We measured the H:Q ratio of both knees using the Biodex Pro Isokinetic Device. Subjects: Eighty-one male and female collegiate athletes. Measurements: We performed analyses for sport, velocity, and side of body for each sex. To compare the means of the concentric H:Q ratios for mean peak torque and mean total work, a 2 × 3 × 4 mixed-factorial analysis of variance was computed for women and a 2 × 2 × 3 mixed-factorial analysis of variance was computed for men. Results: We observed no significant interactions for men and women for the concentric H:Q ratio for mean peak torque. There was a significant mean difference among velocity conditions and a significant difference for men with respect to velocity. No significant differences were found for side of body or sport. Conclusions: The H:Q ratio increased as velocity increased. No differences existed for the H:Q ratio for sport or side of body. PMID:12937479

Fogarty, Tracey D.; Mahaffey, Brian L.

2001-01-01

103

Knee proprioception after exercise-induced muscle damage.  

PubMed

The purpose of the present study was to investigate whether exercise-induced quadriceps muscle damage affects knee proprioception such as joint position sense (JPS), force sense and the threshold to detect passive movement (TTDPM). Fourteen young men performed sets of eccentric quadriceps contractions at a target of 60% of the maximal concentric peak torque until exhaustion; the exercise was interrupted whenever the subject could not complete two sets. Muscle soreness, JPS, the TTDPM and force sense were examined before the exercise as well as one, 24, 48, 72 and 96 h after exercise. The results were compared using one-way repeated-measure ANOVA. Plasma CK activity, collected at the same times, was analyzed by the Friedman's test to discriminate differences between baseline values and each of the other assessment moments (p<0.05). Relative to the proprioception assessment, JPS at 30 and 70 degrees of knee flexion and force sense were significantly decreased up to 48 h, whereas TTDPM decreased significantly at only one hour and 24 h after exercise, at 30 and 70 degrees of the knee flexion, respectively. The results allow the conclusion that eccentric exercise leading to muscle damage alters joint proprioception, suggesting that there might be impairment in the intrafusal fibres of spindle muscles and in the tendon organs. PMID:20301043

Torres, R; Vasques, J; Duarte, J A; Cabri, J M H

2010-06-01

104

Stretching Exercises for Horses: Are They Effective?  

Microsoft Academic Search

This article aims to present research in both animals and humans that support the use of stretching exercises in horses as a means of increasing range of motion, improving body flexibility and posture, and preventing injury by strengthening the supportive tissues. Too often veterinarians may overlook the importance of stretch exercises. This could partially be due to a lack of

Ava Frick

2010-01-01

105

The time-course of voluntary and electrically evoked muscle performance during and after stretch-shortening exercise is different  

Microsoft Academic Search

The aim of the study was to establish the dynamics of maximal voluntary contraction force (MVCF), height of drop jump (DJ) and electrically evoked quadriceps muscle force at different stimulation frequencies during and after 100 DJs (stretch- shortening exercise, SSE). Healthy untrained men (n = 11; age = 21.8 ± 1.7 years) participated in the study. DJs were performed with

Albertas Skurvydas; Gediminas Mamkus; Dalia Mickeviciene; Nerijus Masiulis; Vytautas Streckis

2007-01-01

106

Changes in ventilation related to changes in electromyograph activity during repetitive bouts of isometric exercise in simulated sailing  

Microsoft Academic Search

This study examined the control of ventilation during repetitive bouts of isometric exercise in simulated sailing. Eight male sailors completed four successive 3-min bouts of similar isometric effort on a dinghy simulator, bouts were separated by 15-s rest intervals. Quadriceps muscle integrated electromyograph activity (iEMG) was recorded during each bout and expressed as a percentage of activity during maximal voluntary

I. Vogiatzis; N. C. Spurway; S. Jennett; J. Wilson; J. Sinclair

1996-01-01

107

Questionable Exercises.  

ERIC Educational Resources Information Center

This publication presents general guidelines for exercise prescription that have an anatomical basis but also consider the exerciser's ability to do the exercise correctly. It reviews various common questionable exercises, explaining how some exercises, especially those designed for flexibility and muscle fitness, can cause harm. Safer…

Liemohn, Wendell; Haydu, Traci; Phillips, Dawn

1999-01-01

108

Quadriceps activation normative values and the affect of subcutaneous tissue thickness.  

PubMed

Calculation of the central activation ratio (CAR) using the superimposed burst technique (SIB) is widely used. 0.95 is considered a normal value of the CAR in healthy subjects, but it has not been objectively examined. Since an electrical stimulation penetrates the subcutaneous tissue, the intensity of electrical stimulation may vary depending on the subcutaneous tissue thickness. Subjects performed a maximal voluntary isometric contraction (MVIC) of the quadriceps with the knee at 90°. Once the MVIC reached a plateau, an electrical stimulation was manually delivered to the quadriceps. Quadriceps CAR was quantified using the equation: CAR=MVIC/MVIC+SIB torque. Quadriceps subcutaneous thickness was measured using ultrasound imaging and skinfolder pinch calipers. CAR values were estimated at 0.95 ± 0.04 for dominant and 0.93 ± 0.05 for non-dominant limbs. Pearson's correlation coefficient revealed that there were negative correlations for quadriceps torque output (Nm/kg) and subcutaneous tissue thickness measured by ultrasound imaging (dominant: r=-0.54, p<0.001; non-dominant: r=-0.53, p<0.001). We found no relationship between CAR and subcutaneous tissue thickness. A CAR of 0.95 may be considered full activation in healthy young adults, and CAR in healthy adults generated by the SIB technique may not be dependent on subcutaneous thickness. PMID:20947373

Park, Jihong; Hopkins, J Ty

2011-02-01

109

ASSOCIATION BETWEEN LONG-TERM QUADRICEPS WEAKNESS AND EARLY WALKING MUSCLE CO-CONTRACTION AFTER TOTAL KNEE ARTHROPLASTY  

PubMed Central

INTRODUCTION Quadriceps weakness is one of the primary post-operative impairments that persist long term for patients after total knee arthroplasty (TKA). We hypothesized that early gait muscle recruitment patterns of the quadriceps and hamstrings with diminished knee performance at 3 months after surgery would be related to long-term quadriceps strength at one year after TKA. METHODS Twenty-one subjects who underwent primary unilateral TKA and 14 age-matched healthy controls were analyzed. At three months after TKA, the maximum voluntary isometric contraction of quadriceps and a comprehensive gait analysis were performed. Quadriceps strength was assessed again at one year after surgery. RESULTS Quadriceps muscle recruitment of the operated limb was greater than the non-operated limb during the loading response of gait (p=0.03), but there were no significant differences in hamstring recruitment or co-contraction between limbs (p>0.05). There were significant differences in quadriceps muscle recruitment during gait between the non-operated limb of TKA group and healthy control group (p<0.05). The TKA group showed a significant inverse relationship between one year quadriceps strength and co-contraction (r = ?0.543) and hamstring muscle recruitment (r = ?0.480) during loading response at 3 months after TKA. CONCLUSIONS The results revealed a reverse relationship where stronger patients tended to demonstrate lower quadriceps recruitment at 3 months post-surgery that was not observed in the healthy peer group. The altered neuromuscular patterns of quadriceps and hamstrings during gait may influence chronic quadriceps strength in individuals after TKA. PMID:23352711

Yoshida, Yuri; Mizner, Ryan L.; Snyder-Mackler, Lynn

2013-01-01

110

In vivo specific tension of the human quadriceps femoris muscle.  

PubMed

It is not known to what extent the inter-individual variation in human muscle strength is explicable by differences in specific tension. To investigate this, a comprehensive approach was used to determine in vivo specific tension of the quadriceps femoris (QF) muscle (Method 1). Since this is a protracted technique, a simpler procedure was also developed to accurately estimate QF specific tension (Method 2). Method 1 comprised calculating patellar tendon force (F (t)) in 27 young, untrained males, by correcting maximum voluntary contraction (MVC) for antagonist co-activation, voluntary activation and moment arm length. For each component muscle, the physiological cross-sectional area (PCSA) was calculated as volume divided by fascicle length during MVC. Dividing F (t) by the sum of the four PCSAs (each multiplied by the cosine of its pennation angle during MVC) provided QF specific tension. Method 2 was a simplification of Method 1, where QF specific tension was estimated from a single anatomical CSA and vastus lateralis muscle geometry. Using Method 1, the variability in MVC (18%) and specific tension (16%) was similar. Specific tension from Method 1 (30 +/- 5 N cm(-2)) was similar to and correlated with that of Method 2 (29 +/- 5 N cm(-2); R (2) = 0.67; P < 0.05). In conclusion, most of the inter-individual variability in MVC torque remains largely unexplained. Furthermore, a simple method of estimating QF specific tension provided similar values to the comprehensive approach, thereby enabling accurate estimations of QF specific tension where time and resources are limited. PMID:19468746

Erskine, Robert M; Jones, David A; Maganaris, Constantinos N; Degens, Hans

2009-08-01

111

Enhancing Relationships Strengthening Commitment  

E-print Network

of healing Realistic expectations and acceptance of the other person's frailties The ability of partners similar strategies: Keep a realistic perspective of the crisis. This keeps the effects from spreading stress reliever. Exercise control. It's natural to feel fear and anger during a crisis. There are ways

Leistikow, Bruce N.

112

Impact of joint status on contraction steadiness of m. quadriceps femoris in people with severe haemophilia.  

PubMed

Impaired contraction steadiness of lower limb muscles affects functional performance and may increase injury risk. We hypothesize that haemophilic arthropathy of the knee and the strength status of quadriceps are relevant factors which compromise a steady contraction. This study addresses the questions if impaired steadiness of the quadriceps is verifiable in people with haemophilia (PWH) and whether a connection between the status of the knee joint and quadriceps strength exists. A total of 157 PWH and 85 controls (C) performed a strength test with a knee extensor device to evaluate their bilateral and unilateral maximal quadriceps strength and steadiness. Isometric steadiness was measured by the coefficient of variation of maximum peak torque (CV-MVIC in %). For classification of the knee joint status the World Federation of Haemophilia (WFH) score was used. Lower steadiness (higher CV values) was found in PWH compared with C during bilateral [PWH vs. C; 0.63 (0.36/1.13) vs. 0.35 (0.15/0.72), median (Q25/Q75) P < 0.001] and unilateral trials [left leg: 0.70 (0.32/1.64) vs. 0.50 (0.23/1.04), P < 0.05; right leg: 0.68 (0.29/1.51) vs. 0.39 (0.18/0.68), P < 0.001]. PWH with a WFH score difference (?1) between their extremities showed a less steady contraction in the more affected extremity (P < 0.05). More unsteady contractions have also been found in extremities with lower quadriceps strength compared with the contralateral stronger extremities (P < 0.001), whereby the weaker extremities were associated with a worse joint status (P < 0.001). The results of this study verify an impaired ability to realize a steady contraction of quadriceps in PWH and the influence of joint damage and strength on its manifestation. PMID:25156626

Brunner, A; Stäuber, F; Göhler, S; Czepa, D; Wendel, M; Seuser, A; Hilberg, T

2014-11-01

113

“Central” Quadriceps Tendon Harvest With Patellar Bone Plug: Surgical Technique Revisited  

PubMed Central

The objective of this article is to review the surgical technique for quadriceps tendon graft harvest while highlighting an additional technical note that has not been previously emphasized. The quadriceps tendon typically inserts eccentrically on the superior pole of the patella. By shifting the soft-tissue harvest to a location just off the medial edge of the tendon, the adjoining patellar bone plug will be centered on the superior pole of the patella, reducing the risk of an iatrogenic patellar fracture. PMID:24400194

Scully, William F.; Wilson, David J.; Arrington, Edward D.

2013-01-01

114

The Relationship between Quadriceps Thickness, Radiological Staging, and Clinical Parameters in Knee Osteoarthritis  

PubMed Central

[Purpose] The aim of this study was to investigate the relationship between clinical parameters, radiological staging and evaluated ultrasound results of quadriceps muscle thickness in knee osteoarthritis. [Subjects] The current study comprised 75 patients (51 female, 24 male) with a mean age of 57.9±5.2?years (range 40–65 years) and a diagnosis of osteoarthritis in both knees. [Methods] Knee radiographs were evaluated according to the Kellgren-Lawrence grading system. Clinical evaluation performed with the visual analog scale (VAS), Western Ontario and McMaster Osteoarthritis Index (WOMAC), the 50-meter walking test, and the 10-step stair test. The thickness of the muscle layer of the quadriceps femoris (M. vastus intermedius and M. rectus femoris) was measured with high-resolution real-time ultrasonography. [Results] The results of this study showed a significant negative correlation between quadriceps thickness and age, duration of disease, stage of knee OA, and VAS, WOMAC, 50-m walking test, and 10-step stair test scores. [Conclusion] The evaluation of quadriceps muscle thickness with ultrasound can be considered a practical and economical method in the diagnosis and follow-up of knee osteoarthritis. PMID:25013299

Koca, Irfan; Boyaci, Ahmet; Tutoglu, Ahmet; Boyaci, Nurefsan; Ozkur, Ayhan

2014-01-01

115

A Simple Clinical Measure of Quadriceps Muscle Strength Identifies Responders to Pulmonary Rehabilitation  

PubMed Central

The aim was to determine if baseline measures can predict response to pulmonary rehabilitation in terms of six-minute walk distance (6MWD) or quality of life. Participants with COPD who attended pulmonary rehabilitation between 2010 and 2012 were recruited. Baseline measures evaluated included physical activity, quadriceps strength, comorbidities, inflammatory markers, and self-efficacy. Participants were classified as a responder with improvement in 6MWD (criteria of ?25?m or ?2SD) and Chronic Respiratory Questionnaire (CRQ; ?0.5 points/question). Eighty-five participants with a mean (SD) age of 67(9) years and a mean forced expiratory volume in one second of 55(22)% were studied. Forty-nine and 19 participants were responders when using the 6MWD criteria of ?25?m and ?61.9?m, respectively, with forty-four participants improving in CRQ. In a regression model, responders in 6MWD (?25?m criteria) had lower baseline quadriceps strength (P = 0.028) and higher baseline self-efficacy scores (P = 0.045). Independent predictors of 6MWD response (?61.9?m criteria) were participants with metabolic disease (P = 0.007) and lower baseline quadriceps strength (P = 0.016). Lower baseline CRQ was the only independent predictor of CRQ response. A participant with relatively lower baseline quadriceps strength was the strongest independent predictor of 6MWD response. Metabolic disease may predict 6MWD response, but predictors of CRQ response remain unclear. PMID:24672721

Walsh, James R.; Morris, Norman R.; McKeough, Zoe J.; Yerkovich, Stephanie T.; Paratz, Jenny D.

2014-01-01

116

Effects of Tourniquet Use on Quadriceps Function and Pain in Total Knee Arthroplasty  

PubMed Central

Purpose A pneumatic tourniquet is commonly used in total knee arthroplasty (TKA) to improve surgical field visualisation but may result in quadriceps muscle ischaemia. We performed this study to analyse the effect of the tourniquet on recovery following TKA. Materials and Methods A prospective randomised single-blinded trial was undertaken to examine the effect of the tourniquet on post-operative pain, swelling, blood loss, quadriceps function and outcome following TKA. Twenty patients with osteoarthritis of the knee were randomised to tourniquet or no tourniquet groups. Quadriceps function was assessed using surface electromyography (EMG) during active knee extension. Results The no tourniquet group had significantly less pain in the early post-operative period compared to the tourniquet group. There was no difference in Oxford knee score, range of motion, or thigh and knee swelling up to 12 months post-operatively. Quadriceps function, measured by surface EMG, was compromised for the first six months post-surgery by tourniquet use. The radiological cement mantle at the bone prosthesis interface at 12-month follow-up was not affected by the absence of a tourniquet. Conclusions We believe that it is safe and beneficial for our patients to routinely perform TKA without a tourniquet. PMID:25505702

Graham, David; Gillies, Kim; Gillies, R. Mark

2014-01-01

117

Bioenergetics and intermuscular fat in chronic obstructive pulmonary disease-Associated quadriceps weakness.  

PubMed

Introduction: Chronic obstructive pulmonary disease (COPD) is associated with metabolic abnormalities in muscles of the lower limbs, but it is not known whether these abnormalities are generalized or limited to specific muscle groups, nor is there an easy way of predicting their presence. Methods: Metabolism in the quadriceps and biceps of 14 COPD patients and controls was assessed during sustained contraction using 31-phosphorus magnetic resonance spectroscopy ((31) P MRS). T1 MRI was used to measure quadriceps intermuscular adipose tissue (IMAT). Results: COPD patients had prolonged quadriceps phosphocreatine time (patients: 38.8?± 12.7 s; controls: 25.2?±?10.6 s; P?=?0.006) and a lower pH (patents: 6.88?±?0.1; controls: 6.99?±?0.06; P?=?0.002). Biceps measures were not significantly different. IMAT was associated with a nadir pH <7.0 (area under the curve?=?0.84). Conclusion: Anaerobic metabolism during contraction was characteristic of quadriceps, but not biceps, muscles of patients with COPD and was associated with increased IMAT. Because IMAT can be assessed quickly by conventional MRI, it may be a useful approach for identifying patients with abnormal muscle bioenergetics. Muscle Nerve, 2014. PMID:24831173

Shields, Gregory Samuel; Coissi, Graziele S; Jimenez-Royo, Pilar; Gambarota, Giulio; Dimber, Rahul; Hopkinson, Nicholas S; Matthews, Paul M; Brown, Andrew P; Polkey, Michael I

2014-05-16

118

Central Quadriceps Tendon for Anterior Cruciate Ligament ReconstructionPart I: Morphometric and Biomechanical Evaluation  

Microsoft Academic Search

We examined the anatomic and biomechanical adequacy of the central quadriceps tendon as an al ternative graft source for anterior cruciate ligament reconstruction. Morphometry was performed on 15 preserved and 6 fresh-frozen specimens. Biomechani cal testing was performed on the six fresh-frozen spec imens. We initially used a triple suture through the tendon construction, and then clamping directly on the

N. Lindsay Harris; David A. B. Smith; Lisa Lamoreaux; Mark Purnell

1997-01-01

119

Strengthened quantum Hamming bound  

E-print Network

We report two analytical bounds for quantum error-correcting codes that do not have preexisting classical counterparts. Firstly the quantum Hamming and Singleton bounds are combined into a single tighter bound, and then the combined bound is further strengthened via the well-known Lloyd's theorem in classical coding theory, which claims that perfect codes, codes attaining the Hamming bound, do not exist if the Lloyd's polynomial has some non-integer zeros. Our bound characterizes quantitatively the improvement over the Hamming bound via the non-integerness of the zeros of the Lloyd's polynomial. In the case of 1-error correcting codes our bound holds true for impure codes as well, which we conjecture to be always true, and for stabilizer codes there is a 1-logical-qudit improvement for an infinite family of lengths.

Sixia Yu; C. H. Lai; C. H. Oh

2010-05-26

120

Effective Family Strengthening Interventions. Juvenile Justice Bulletin. Family Strengthening Series.  

ERIC Educational Resources Information Center

This bulletin summarizes the results of a training and technology transfer program focussing on strengthening families for the prevention of delinquency. A national search was conducted for representative family strengthening programs, and through a process that involved national conferences, regional training sessions, and technical assistance,…

Alvarado, Rose; Kumpfer, Karol L.

121

Quadriceps oxygenation changes during walking and running on a treadmill  

NASA Astrophysics Data System (ADS)

Vastus lateralis muscle oxygenation was investigated on volunteers as well as muscular dystrophy patients during a walking test, and on volunteers during a free running by a continuous wave near infrared instrument. The data were analyzed using an oxygenation index independent on pathlength changes. Walking did not significantly affect the oxygenation of volunteers and patients. A relative deoxygenation was found only during free running indicating an unbalance between oxygen supply and tissue oxygen extraction. Preliminary measurements of exercising muscle oxygen saturation were performed by a 110 MHz frequency-domain, multisource instrument.

Quaresima, Valentina; Pizzi, Assunta; De Blasi, Roberto A.; Ferrari, Adriano; de Angelis, Marco; Ferrari, Marco

1995-04-01

122

Peripheral muscle endurance and the oxidative profile of the quadriceps in patients with COPD  

PubMed Central

Background: Based on previously reported changes in muscle metabolism that could increase susceptibility to fatigue, we speculated that patients with chronic obstructive pulmonary disease (COPD) have reduced quadriceps endurance and that this will be correlated with the proportion of type I muscle fibres and with the activity of oxidative enzymes. Methods: The endurance of the quadriceps was evaluated during an isometric contraction in 29 patients with COPD (mean (SE) age 65 (1) years; forced expiratory volume in 1 second 37 (3)% predicted) and 18 healthy subjects of similar age. The electrical activity of the quadriceps was recorded during muscle contraction as an objective index of fatigue. The time at which the isometric contraction at 60% of maximal voluntary capacity could no longer be sustained was used to define time to fatigue (TF). Needle biopsies of the quadriceps were performed in 16 subjects in both groups to evaluate possible relationships between TF and markers of muscle oxidative metabolism (type I fibre proportion and citrate synthase activity). Results: TF was lower in patients with COPD than in controls (42 (3) v 80 (7) seconds; mean difference 38 seconds (95% CI 25 to 50), p<0.001). Subjects in both groups had evidence of electrical muscle fatigue at the end of the endurance test. In both groups significant correlations were found between TF and the proportion of type I fibres and citrate synthase activity. Conclusion: Isometric endurance of the quadriceps muscle is reduced in patients with COPD and the muscle oxidative profile is significantly correlated with muscle endurance. PMID:15282387

Allaire, J; Maltais, F; Doyon, J; Noel, M; LeBlanc, P; Carrier, G; Simard, C; Jobin, J

2004-01-01

123

Exercise performance and fatiguability in patients with chronic fatigue syndrome.  

PubMed Central

To examine the role of delay in recovery of peripheral muscle function following exercise in the fatigue experienced by patients with the chronic fatigue syndrome (CFS) and to examine the influence of effort perception in limiting exercise performance in these patients, a study was carried out on a group of twelve patients with chronic fatigue syndrome and 12 sex and age-matched sedentary control subjects. Symptom limited incremental cycle exercise tests including measurements of perceived exertion were performed followed by examination of the contractile properties of the quadriceps muscle group for up to 48 hours. Muscle function was assessed by percutaneous electrical stimulation and maximum voluntary contractions. Muscle function at rest and during recovery was normal in CFS patients as assessed by maximum isometric voluntary contraction, 20:50 Hz tetanic force ratio and maximum relaxation rate. Exercise duration and the relationship between heart rate and work rate during exercise were similar in both groups. CFS patients had higher perceived exertion scores in relation to heart rate during exercise representing a reduced effort sensation threshold of 3.2 units on an unmodified Borg scale in CFS patients. Patients with chronic fatigue syndrome show normal muscle physiology before and after exercise. Raised perceived exertion scores during exercise suggest that central factors are limiting exercise capacity in these patients. PMID:8410041

Gibson, H; Carroll, N; Clague, J E; Edwards, R H

1993-01-01

124

Mechanical, hormonal, and hypertrophic adaptations to 10weeks of eccentric and stretch-shortening cycle exercise training in old males.  

PubMed

The growth promoting effects of eccentric (ECC) contractions are well documented but it is unknown if the rate of stretch per se plays a role in such muscular responses in healthy aging human skeletal muscle. We tested the hypothesis that exercise training of the quadriceps muscle with low rate ECC and high rate ECC contractions in the form of stretch-shortening cycles (SSCs) but at equal total mechanical work would produce rate-specific adaptations in healthy old males age 60-70. Both training programs produced similar improvements in maximal voluntary isometric (6%) and ECC torque (23%) and stretch-shortening cycle function (reduced contraction duration [24%] and enhanced elastic energy storage [12%]) (p<0.05). The rate of torque development increased 30% only after SSC exercise (p<0.05). Resting testosterone and cortisol levels were unchanged but after each program the acute exercise-induced cortisol levels were 12-15% lower (p<0.05). Both programs increased quadriceps size 2.5% (p<0.05). It is concluded that both ECC and SSC exercise training produces favorable adaptations in healthy old males' quadriceps muscle. Although the rate of muscle tension during the SSC vs. ECC contractions was about 4-fold greater, the total mechanical work seems to regulate the hypetrophic, hormonal, and most of the mechanical adaptations. However, SSC exercise was uniquely effective in improving a key deficiency of aging muscle, i.e., its ability to produce force rapidly. PMID:25064038

Váczi, Márk; Nagy, Szilvia A; K?szegi, Tamás; Ambrus, Míra; Bogner, Péter; Perlaki, Gábor; Orsi, Gergely; Tóth, Katalin; Hortobágyi, Tibor

2014-10-01

125

Neuromuscular Control of the Knee During a Resisted Single-Limb Squat Exercise  

Microsoft Academic Search

Background:Closed kinetic chain exercises such as single-limb squats are preferred for knee rehabilitation. A complete understanding of the neuromuscular control of the knee during the single-limb squat is essential to increase the efficiency of rehabilitation programs.Hypothesis:Performing a controlled single-limb squat with resistance to knee flexion and extension will increase the coactivation of the hamstring muscle group, thus reducing the quadriceps\\/hamstrings

Richard K. Shields; Sangeetha Madhavan; Emy Gregg; Jennifer Leitch; Ben Petersen; Sara Salata; Stacey Wallerich

2005-01-01

126

Effects of fatiguing isometric and isotonic exercise on resisted and unresisted reaction time components  

Microsoft Academic Search

Summary  Fractionated resisted and unresisted RT for a knee-extension task was assessed on 12 male subjects over a 10-day treatment period. The first 4 days were baseline days and were designed to stabilize all RT values as well as strength measures. For the next 6 days the subjects were alternately administered isometric and isotonic exercise designed to fatigue the quadriceps musculature.

Alfred F. Morris

1977-01-01

127

Cardiovascular benefits of exercise.  

PubMed

Regular physical activity during leisure time has been shown to be associated with better health outcomes. The American Heart Association, the Centers for Disease Control and Prevention and the American College of Sports Medicine all recommend regular physical activity of moderate intensity for the prevention and complementary treatment of several diseases. The therapeutic role of exercise in maintaining good health and treating diseases is not new. The benefits of physical activity date back to Susruta, a 600 BC physician in India, who prescribed exercise to patients. Hippocrates (460-377 BC) wrote "in order to remain healthy, the entire day should be devoted exclusively to ways and means of increasing one's strength and staying healthy, and the best way to do so is through physical exercise." Plato (427-347 BC) referred to medicine as a sister art to physical exercise while the noted ancient Greek physician Galen (129-217 AD) penned several essays on aerobic fitness and strengthening muscles. This article briefly reviews the beneficial effects of physical activity on cardiovascular diseases. PMID:22807642

Agarwal, Shashi K

2012-01-01

128

Preserved function and reduced angiogenesis potential of the quadriceps in patients with mild COPD  

PubMed Central

Background Little is known about limb muscle abnormalities in mild COPD. Inactivity and systemic inflammation could play a role in the development of limb muscle dysfunction in COPD. The objective of the present study was to characterize quadriceps function, enzymatic activities and morphometry, levels of plasma inflammatory markers and physical activity levels in daily life (PAdl) in patients with mild COPD (GOLD 1). Methods Mid-thigh muscle cross-sectional area (MTCSA), quadriceps strength, endurance, fiber-type distribution, capillarity, pro-angiogenesis factors (VEGF-A, angiopoietin I and II) and muscle oxidative capacity were assessed in 37 patients with mild COPD and 19 controls. Systemic inflammatory markers (CRP, IL-6, TNF-?, Fibrinogen, SP-D) and PAdl were assessed. Results MTCSA, quadriceps strength and endurance were not different between COPD and controls. Capillarity and muscle oxidative capacity were all preserved in mild COPD. Reduced pro-angiogenesis factor mRNA expression was seen in COPD. The level of moderately active intensity (>3 METs) was significantly lower in mild COPD and, in multiple regression analyses, the level of physical activity was a determinant of muscle oxidative capacity and capillarization. No between-group differences were found regarding muscle oxidative stress while circulating IL-6 levels were elevated in mild COPD. Conclusions The quadriceps muscle function was preserved in mild COPD although a reduced potential for angiogenesis was found. The reduced level of daily activities and evidence of systemic inflammation in these individuals suggest that these factors precede the development of overt limb muscle dysfunction in COPD. PMID:24438094

2014-01-01

129

Quadriceps fat pad edema: significance on magnetic resonance images of the knee  

Microsoft Academic Search

Objective  While clinically reading magnetic resonance (MR) images of the knees we have occasionally noted edema within the suprapatellar\\u000a fat pad, with mass effect both on the suprapatellar joint recess posteriorly, and on the quadriceps tendon anteriorly. This\\u000a MR appearance is analogous to Hoffa’s disease described in the infrapatellar fat pad. We sought to evaluate the frequency\\u000a and pattern of this

Nogah Shabshin; Mark E. Schweitzer; William B. Morrison

2006-01-01

130

Size and strength of the respiratory and quadriceps muscles in patients with chronic asthma  

Microsoft Academic Search

Size and strength of the respiratory and quadriceps muscles in patients with chronic asthma. P.F. de Bruin, J. Ueki, A. Watson, N.B. Pride. ©ERS Journals 1997. ABSTRACT: There have been few studies of respiratory and limb muscle size and function in middle-aged patients with asthma and persistent airways obstruction. We have compared the forces generated by the respiratory and thigh

P. F. de Bruin; J. Ueki; A. Watson; N. B. Pride

1997-01-01

131

A neuro-control system for the knee joint position control with quadriceps stimulation  

Microsoft Academic Search

A neuro-control system was designed to control the knee joint to move in accordance with the desired trajectory of movement through stimulation of quadriceps muscle. This control system consisted of a neural controller and a fixed parameter proportional-integral-derivative (PID) feedback controller, which was designated as a neuro-PID controller. A multilayer feedforward time-delay neural network was used and trained as an

Gwo-Ching Chang; Jer-Junn Lub; Gon-Der Liao; Jin-Shin Lai; Cheng-Kung Cheng; Bor-Lin Kuo; Te-Son Kuo

1997-01-01

132

In-vitro measurement of the human knee joint motion during quadriceps leg raising  

Microsoft Academic Search

This paper represents a three-dimensional motion analysis of the human knee joint under given conditions of loading and constraint.\\u000a As the knee is extended by a known force applied to the quadriceps tendon, relative displacements of the femur, tibia, and\\u000a patella are measured using a video motion analysis system. The most prominent motion of the tibia is external rotation and

Seonpil Kim

1998-01-01

133

Bilateral eccentric and concentric torque of quadriceps and hamstring muscles in females and males  

Microsoft Academic Search

Summary  This study assessed maximum eccentric (ECC) and concentric (CON) torque of quadriceps (QUAD) and hamstring (HAM) muscle groups\\u000a in healthy females (n=13) and males (n=27). Peak torques (PT) of bilateral muscle actions were recorded at constant angular velocities of 0.52, 1.57 and 2.61 rad·s?1. The QUADcon and HAMcon PT decreased (pecc and HAMecc PT increased (pecc PT decreased (pecc PT

Erland B. Colliander; Per A. Tesch

1989-01-01

134

Evaluation of Electromyographic Biofeedback for the Quadriceps Femoris: A Systematic Review  

PubMed Central

Objective: To critically review evidence for the effectiveness of electromyographic biofeedback (EMGB) of the quadriceps femoris muscle in treating various knee conditions. Data Sources: Databases used to locate randomized controlled trials included PubMed (1980–2010), Cumulative Index of Nursing and Allied Health Literature (CINAHL, 1995–2007), Web of Science (1986–2010), SPORTDiscus (1990–2007), and Physiotherapy Evidence Database (PEDro). Key words were knee and biofeedback. Study Selection: The criteria for selection were clinical randomized controlled trials in which EMGB of the quadriceps femoris was used for various knee conditions of musculoskeletal origin. Trials were excluded because of research designs other than randomized controlled trials, articles published in a non-English language, inclusion of healthy research participants, inability to identify EMGB as the source of clinical improvement, and lack of pain, functional outcome, or quadriceps torque as outcome measures. Data Extraction: Twenty specific data points were abstracted from each clinical trial under the broad categories of attributes of the patient and injury, treatment variables for the EMGB group, treatment variables for the control group, and attributes of the research design. Data Synthesis: Eight trials yielded a total of 319 participants with patellofemoral pain syndrome (n = 86), anterior cruciate ligament reconstruction (n = 52), arthroscopic surgery (n = 91), or osteoarthritis (n = 90). The average methodologic score of the included studies was 4.6/10 based on PEDro criteria. Pooled analyses demonstrated heterogeneity of the included studies, rendering the interpretation of the pooled data inappropriate. The EMGB appeared to benefit short-term postsurgical pain or quadriceps strength in 3 of 4 postsurgical investigations but was ineffective for chronic knee conditions such as patellofemoral pain and osteoarthritis in all 4 studies. Because the findings are based on limited data, caution is warranted until more randomized controlled trials are conducted to support or refute the general trends observed in this report. PMID:22488142

Wasielewski, Noah J.; Parker, Tonya M.; Kotsko, Kevin M.

2011-01-01

135

Arthrogenic Muscle Response of the Quadriceps and Hamstrings With Chronic Ankle Instability  

PubMed Central

Context: An arthrogenic muscle response (AMR) of the soleus and peroneal muscles has been previously demonstrated in individuals with chronic ankle instability (CAI), but the presence of AMR in muscles acting on joints proximal to unstable ankles has not been previously explored. Objective: To determine if AMR is present in the quadriceps and hamstrings muscles of those with and without unilateral CAI. Design: Case control. Setting: University research laboratory. Patients or Other Participants: Twenty subjects with unilateral CAI (12 males, 8 females: age = 19.9 ± 3.7 years; height = 170.3 ± 15.6 cm; mass = 78.0 ± 23.1 kg) and 21 controls (16 males, 5 females: age = 23.2 ± 5.4 years; height = 173.9 ± 12.7 cm; mass = 87.2 ± 24.6 kg) with no previous ankle injuries. Main Outcome Measure(s): The central activation ratio (CAR), a measure of motoneuron pool excitability during maximal voluntary isometric contraction, for the hamstrings and quadriceps muscles was measured in both limbs using the superimposed burst technique. Results: The CAI group demonstrated quadriceps CARs that were significantly larger in their involved limbs (.87 ± .09), as compared with their uninvolved limbs (.84 ± .08), whereas no significant side-to-side difference was seen in the control group (sham involved = .80 ± .11, sham uninvolved = .81 ± .11). When values from both the involved and uninvolved limbs were averaged, the hamstrings CAR was significantly lower for the CAI group (.94 ± .03) than for the control group (.96 ± .03). Conclusions: Arthrogenic inhibition of the hamstrings muscles bilaterally and facilitation of the quadriceps muscle ipsilateral to the involved limb were noted in subjects with unilateral CAI. Motoneuron pool excitability appears to be altered in muscles that act on joints proximal to the ankle in those with unilateral CAI. PMID:18059990

Sedory, Edward J; McVey, Eric D; Cross, Kevin M; Ingersoll, Christopher D; Hertel, Jay

2007-01-01

136

An Acute Bout of Quadriceps Muscle Stretching has no Influence on Knee Joint Proprioception  

PubMed Central

The main objective of this study was to determine if an acute bout of static stretching of the quadriceps muscle affects the sense of joint position, the threshold to detect passive movement, and the sense of force. Thirty young, healthy men (age : 22.1 ± 2.7 years) were randomly divided into two groups. The Stretching Group (n=15) underwent stretching of the dominant quadriceps muscle, which comprised ten passive stretches lasting 30 seconds each, while the Control Group (n=15) remained seated for the same length of time. A repeated-measures analysis of variance was used to establish intragroup differences over time, and an independent sample t-test was used to compare the dependent variables between groups at each moment. None of the measurements revealed any significant change between both groups in each assessment moment or between moments within groups (p>0.05). This study demonstrated that static quadriceps muscle stretching has no effect on the sense of knee joint position, threshold to detect passive movement, and force sense, suggesting that stretching does not have appreciable effect on the spindle firing characteristics and tendon organs activation. PMID:23486744

Torres, Rui; Duarte, José Alberto; Cabri, Jan MH

2012-01-01

137

Asymptomatic Achilles, patellar, and quadriceps tendinopathy: a longitudinal clinical and ultrasonographic study in elite fencers.  

PubMed

Lower limb tendon changes detected at imaging are common among asymptomatic athletes. We aimed to prospectively assess the clinical status, tendon structure, and vascularity of lower limb tendons of elite fencers, and predict the risk of developing symptoms over time. Clinical examination, changes at ultrasonography (US), and Power Doppler (PD) flow of both the Achilles, patellar, and quadriceps tendon were assessed in 37 elite fencers in January 2007 and 3 years after. Two hundred and twenty-two tendons were examined. At the last appointment, patellar tendons diagnosed as abnormal at baseline were more likely to develop symptoms than those normal at baseline (P?quadriceps tendons were no predictive for development of symptoms over years. A very low percentage of tendons diagnosed as normal at baseline (1.45%) showed US abnormalities at 3-year follow-up. In asymptomatic elite fencers, structural changes are relatively common at US and PD assessment of Achilles, quadriceps, and patellar tendons. It seems unlikely that additional PD investigations provide further information or change prognosis in patients with US diagnosis of tendinopathy. PMID:22092963

Giombini, A; Dragoni, S; Di Cesare, A; Di Cesare, M; Del Buono, A; Maffulli, N

2013-06-01

138

Electromyographic Analysis of Single-Leg, Closed Chain Exercises: Implications for Rehabilitation After Anterior Cruciate Ligament Reconstruction  

PubMed Central

Objective: Many knee rehabilitation studies have examined open and closed kinetic chain exercises. However, most studies focus on 2-legged, closed chain exercise. The purpose of our study was to characterize 1-legged, closed chain exercise in young, healthy subjects. Subjects: Eighteen normal subjects (11 men, 7 women; age, 24.6 ± 1.6 years) performed unsupported, 1-legged squats and step-ups to approximately tibial height. Measurements: Knee angle data and surface electromyographic activity from the thigh muscles were recorded. Results: The maximum angle of knee flexion was 111 ± 23° for squats and 101 ± 16° for step-ups. The peak quadriceps activation was 201 ± 66% maximum voluntary isometric contraction, occurring at an angle of 96 ± 16° for squats. Peak quadriceps activation was 207 ± 50% maximum voluntary isometric contraction and occurred at 83 ± 12° for step-ups. Conclusions: The high and sustained levels of quadriceps activation indicate that 1-legged squats and step-ups would be effective in muscle rehabilitation. As functional, closed chain activities, they may also be protective of anterior cruciate ligament grafts. Because these exercises involve no weights or training equipment, they may prove more cost effective than traditional modes of rehabilitation. PMID:12937438

Beutler, Anthony I.; Cooper, Leslie W.; Kirkendall, Don T.; Garrett, William E.

2002-01-01

139

Electromyographic Analysis of Single-Leg, Closed Chain Exercises: Implications for Rehabilitation After Anterior Cruciate Ligament Reconstruction.  

PubMed

OBJECTIVE: Many knee rehabilitation studies have examined open and closed kinetic chain exercises. However, most studies focus on 2-legged, closed chain exercise. The purpose of our study was to characterize 1-legged, closed chain exercise in young, healthy subjects. SUBJECTS: Eighteen normal subjects (11 men, 7 women; age, 24.6 +/- 1.6 years) performed unsupported, 1-legged squats and step-ups to approximately tibial height. MEASUREMENTS: Knee angle data and surface electromyographic activity from the thigh muscles were recorded. RESULTS: The maximum angle of knee flexion was 111 +/- 23 degrees for squats and 101 +/- 16 degrees for step-ups. The peak quadriceps activation was 201 +/- 66% maximum voluntary isometric contraction, occurring at an angle of 96 +/- 16 degrees for squats. Peak quadriceps activation was 207 +/- 50% maximum voluntary isometric contraction and occurred at 83 +/- 12 degrees for step-ups. CONCLUSIONS: The high and sustained levels of quadriceps activation indicate that 1-legged squats and step-ups would be effective in muscle rehabilitation. As functional, closed chain activities, they may also be protective of anterior cruciate ligament grafts. Because these exercises involve no weights or training equipment, they may prove more cost effective than traditional modes of rehabilitation. PMID:12937438

Beutler, Anthony I; Cooper, Leslie W; Kirkendall, Don T; Garrett, William E

2002-03-01

140

Changes in exercises are more effective than in loading schemes to improve muscle strength.  

PubMed

This study investigated the effects of varying strength exercises and loading scheme on muscle cross-sectional area (CSA) and maximum strength after 4 strength training loading schemes: constant intensity and constant exercise (CICE), constant intensity and varied exercise (CIVE), varied intensity and constant exercise (VICE), varied intensity and varied exercise (VIVE). Forty-nine individuals were allocated into 5 groups: CICE, CIVE, VICE, VIVE, and control group (C). Experimental groups underwent twice a week training for 12 weeks. Squat 1 repetition maximum was assessed at baseline and after the training period. Whole quadriceps muscle and its heads CSA were also obtained pretraining and posttraining. The whole quadriceps CSA increased significantly (p ? 0.05) in all of the experimental groups from pretest to posttest in both the right and left legs: CICE: 11.6 and 12.0%; CIVE: 11.6 and 12.2%; VICE: 9.5 e 9.3%; and VIVE: 9.9 and 11.6%, respectively. The CIVE and VIVE groups presented hypertrophy in all of the quadriceps muscle heads (p ? 0.05), whereas the CICE and VICE groups did not present hypertrophy in the vastus medialis and rectus femoris (RF), and in the RF muscles, respectively (p > 0.05). The CIVE group had greater strength increments than the other training groups (effect size confidence limit of the difference [ESCLdiff] CICE: 1.41-1.56; VICE: 2.13-2.28; VIVE: 0.59-0.75). Our findings suggest: (a) CIVE is more efficient to produce strength gains for physically active individuals; (b) as long as the training intensity reaches an alleged threshold, muscle hypertrophy is similar regardless of the training intensity and exercise variation. PMID:24832974

Fonseca, Rodrigo M; Roschel, Hamilton; Tricoli, Valmor; de Souza, Eduardo O; Wilson, Jacob M; Laurentino, Gilberto C; Aihara, André Y; de Souza Leão, Alberto R; Ugrinowitsch, Carlos

2014-11-01

141

An in vivo analysis of the effect of transcutaneous electrical stimulation of the quadriceps and hamstrings on anterior cruciate ligament deformation  

Microsoft Academic Search

Transcutaneous electrical muscle stimulation (TEMS) has been advocated as a method to rehabilitate the postoperative ACL repaired\\/reconstructed lower ex tremity. Isolated quadriceps contraction can potentially disrupt the ACL repair\\/reconstruction; to minimize this risk simultaneous quadriceps and hamstring stimulation has been used. This study measured the in vivo defor mation of the ACL during TEMS of the quadriceps and hamstrings.Six legs

Christopher C. Kain; John A. McCarthy; Steve Arms; Malcolm H. Pope; J. Richard Steadman; Paul R. Manske; Robert A. Shively

1988-01-01

142

Volcanological Exercises  

NSDL National Science Digital Library

This homework exercise, which builds on knowledge gained in previous homework exercises located at the same site, asks students in an undergraduate class at Tulane University to answer some basic questions about volcanoes, and to determine the volcanic hazards associated with Mt. Rainier, Washington; Montserrat, West Indies; and Long Valley Caldera, California by searching the World Wide Web.

Nelson, Stephen

143

Budget Exercise.  

ERIC Educational Resources Information Center

Following a discussion of the factors to be considered in constructing feasible college budgets, an exercise in budget development is presented involving a hypothetical community college with 2,500 full-time equivalent (FTE) students, 500 in developmental education, 750 each in transfer and technical programs, and 500 undecided. Exercise

Clowes, Darrel A.

144

Frequent low-load ischemic resistance exercise to failure enhances muscle oxygen delivery and endurance capacity.  

PubMed

This study investigated the effects of frequent low-load ischemic resistance exercise performed to failure on quadriceps size and performance, muscle activation, oxygen kinetics and cardiovascular responses. Ten healthy males performed knee-extension exercise for 4 weeks (4 sessions/week) at 15% maximal voluntary muscle contraction (MVC). One leg was trained with free blood flow (C-leg) while in the other leg (I-leg) ischemia was induced by an inflatable cuff (?230 mmHg). Quadriceps cross-sectional area (CSA) of the I-leg increased by 3.4% (P<0.05). A tendency for smaller increase in muscle CSAs at the cuff level was observed. MVC force did not change in either leg, whereas the number of repetitions during exercise test to failure increased (P<0.01) by 63% in I-leg and 36% in C-leg. The decrease in muscle oxygenated hemoglobin concentration acquired by NIRS was attenuated (P<0.01) by 56% in I-leg and 21% in C-leg. Electromyographic amplitude of rectus femoris in I-leg was ?45% lower (P<0.025) during the ischemic test. Also, ?9% increase (P<0.05) in pre-exercise diastolic pressure was observed. In conclusion, substantial gains in muscle endurance capacity were induced, which were associated with enhanced muscle oxygen delivery. The potential negative effects of ischemic exercise with high cuff pressure on muscle and nerve and on arterial pressure regulation need further investigation. PMID:21385216

Kacin, A; Strazar, K

2011-12-01

145

Summer Science Can Strengthen Skills.  

ERIC Educational Resources Information Center

Described are 22 activities which can be done by students outside of school. Topics include the seashore, shadows, restaurants, water, amusement parks, factories, museums, camping, weather, animals, photography, plants, food, and exercise. (CW)

Pugh, Ava F.; Smith, Ruby

1989-01-01

146

Preactivation of the quadriceps muscle could limit cranial tibial translation in a cranial cruciate ligament deficient canine stifle.  

PubMed

Cranial cruciate ligament (CrCL) deficiency is the leading cause of lameness of the canine stifle. Application of tension in the quadriceps muscle could trigger cranial tibial translation in case of CrCL rupture. We replaced the quadriceps muscle and the gastrocnemius muscle by load cells and turn-buckles. First, eight canine limbs were placed in a servo-hydraulic testing machine, which applied 50% of body weight (BW). In a second phase, the CrCL was transected, and the limbs were tested in a similar manner. In a third phase, a quadriceps pretension of 15% BW was applied and limbs were again tested in a similar manner. Cranial tibial translation was significantly decreased in CrCL deficient stifles (p?quadriceps pretension was applied. These findings indicate that quadriceps pretension could play a role in the stability of a CrCL deficient stifle and should then be considered in rehabilitation programs and conservative treatment of CrCL rupture in dogs. PMID:25487559

Ramirez, Juan M; Lefebvre, Michael; Böhme, Beatrice; Laurent, Cédric; Balligand, Marc

2015-02-01

147

Interstitial pH, K(+), lactate, and phosphate determined with MSNA during exercise in humans  

NASA Technical Reports Server (NTRS)

The purpose of the present study was to use the microdialysis technique to simultaneously measure the interstitial concentrations of several putative stimulators of the exercise pressor reflex during 5 min of intermittent static quadriceps exercise in humans (n = 7). Exercise resulted in approximately a threefold (P < 0.05) increase in muscle sympathetic nerve activity (MSNA) and 13 +/- 3 beats/min (P < 0.05) and 20 +/- 2 mmHg (P < 0.05) increases in heart rate and blood pressure, respectively. During recovery, all reflex responses quickly returned to baseline. Interstitial lactate levels were increased (P < 0.05) from rest (1.1 +/- 0.1 mM) to exercise (1. 6 +/- 0.2 mM) and were further increased (P < 0.05) during recovery (2.0 +/- 0.2 mM). Dialysate phosphate concentrations were 0.55 +/- 0. 04, 0.71 +/- 0.05, and 0.48 +/- 0.03 mM during rest, exercise, and recovery, respectively, and were significantly elevated during exercise. At the onset of exercise, dialysate K(+) levels rose rapidly above resting values (4.2 +/- 0.1 meq/l) and continued to increase during the exercise bout. After 5 min of contractions, dialysate K(+) levels had peaked with an increase (P < 0.05) of 0.6 +/- 0.1 meq/l and subsequently decreased during recovery, not being different from rest after 3 min. In contrast, H(+) concentrations rapidly decreased (P < 0.05) from resting levels (69.4 +/- 3.7 nM) during quadriceps exercise and continued to decrease with a mean decline (P < 0.05) of 16.7 +/- 3.8 nM being achieved after 5 min. During recovery, H(+) concentrations rapidly increased and were not significantly different from baseline after 1 min. This study represents the first time that skeletal muscle interstitial pH, K(+), lactate, and phosphate have been measured in conjunction with MSNA, heart rate, and blood pressure during intermittent static quadriceps exercise in humans. These data suggest that interstitial K(+) and phosphate, but not lactate and H(+), may contribute to the stimulation of the exercise pressor reflex.

MacLean, D. A.; Imadojemu, V. A.; Sinoway, L. I.

2000-01-01

148

Effects of Cervical Deep Muscle Strengthening in a Neck Pain: A Patient with Klippel-Feil Syndrome  

PubMed Central

[Purpose] This study aimed to identify the effects of cervical deep muscle strengthening (CDS) on neck pain in a patient with Klippel-Feil syndrome (KFS). [Subjects and Methods] The subjects was a 39?year-old woman with neck pain and KFS that included incomplete block vertebrae in the C2–3 segments and block vertebrae in the C6–7 segments. The subject performed an exercise program including cervical strengthening exercise (level 1) and CDS exercise (level 2) for 6 weeks. Neck pain intensity was measured using the visual analogue scale (VAS) and the pressure pain threshold (PPT). All measurements were obtained before and after the CDS exercise program. [Results] The VAS and PPT measurements decreased; range of motion in the cervical joint increased. [Conclusion] CDS exercises were effective interventions for reducing neck pain in a patient with Klippel-Feil syndrome. PMID:25540517

Bae, Youngsook

2014-01-01

149

Effects of cervical deep muscle strengthening in a neck pain: a patient with klippel-feil syndrome.  

PubMed

[Purpose] This study aimed to identify the effects of cervical deep muscle strengthening (CDS) on neck pain in a patient with Klippel-Feil syndrome (KFS). [Subjects and Methods] The subjects was a 39?year-old woman with neck pain and KFS that included incomplete block vertebrae in the C2-3 segments and block vertebrae in the C6-7 segments. The subject performed an exercise program including cervical strengthening exercise (level 1) and CDS exercise (level 2) for 6 weeks. Neck pain intensity was measured using the visual analogue scale (VAS) and the pressure pain threshold (PPT). All measurements were obtained before and after the CDS exercise program. [Results] The VAS and PPT measurements decreased; range of motion in the cervical joint increased. [Conclusion] CDS exercises were effective interventions for reducing neck pain in a patient with Klippel-Feil syndrome. PMID:25540517

Bae, Youngsook

2014-12-01

150

The Effect of Quadriceps Strength and Proprioception on Risk for Knee Osteoarthritis  

PubMed Central

Purpose: Impaired quadriceps strength and joint position sense (JPS) have been linked with knee osteoarthritis (OA) cross-sectionally. While neither has been independently associated with incident radiographic OA, their combination may mediate risk. The purpose of this study was to determine whether better sensoriomotor function protects against development of incident radiographic or symptomatic knee OA. Methods: The Multicenter Osteoarthritis (MOST) Study, is a longitudinal study of adults age 50-79 years at high risk for knee OA. Participants underwent bilateral, weight bearing, fixed-flexion radiographs, JPS acuity tests, and isokinetic quadriceps strength tests. The relationships between combinations of the tertiles of sex-specific baseline peak strength and mean JPS, and development of incident radiographic (Kellgren-Lawrence (KL) grade ?2) or symptomatic knee OA (KL grade ?2 and frequent knee pain or stiffness) at 30-month follow-up were evaluated. Secondary analyses defined JPS as the variance over the 10 JPS trials, and also assessed the interaction of strength and JPS in predicting each outcome. Results: The study of incident radiographic knee OA included 1390 participants (age 61.2±7.9 years and BMI 29.4±5.1 kg/m2) and the study of incident symptomatic knee OA included 1829 participants (age 62.2±8.0 years and BMI 30.0±5.4 kg/m2). Greater strength at baseline protected against incident symptomatic but not radiographic knee OA regardless of JPS tertile. There was no significant relationship between the strength–JPS interaction and the development of radiographic or symptomatic knee OA. Conclusion: The finding that quadriceps strength protected against incident symptomatic but not radiographic knee OA regardless of JPS tertile suggests that strength may be more important than JPS in mediating risk for knee OA. PMID:20351594

Segal, Neil A.; Glass, Natalie A.; Felson, David T.; Hurley, Michael; Yang, Mei; Nevitt, Michael; Lewis, Cora E.; Torner, James C.

2010-01-01

151

Association of Quadriceps and Hamstrings Cocontraction Patterns With Knee Joint Loading  

PubMed Central

Context: Sex differences in neuromuscular control of the lower extremity have been identified as a potential cause for the greater incidence of anterior cruciate ligament (ACL) injuries in female athletes compared with male athletes. Women tend to land in greater knee valgus with higher abduction loads than men. Because knee abduction loads increase ACL strain, the inability to minimize these loads may lead to ACL failure. Objective: To investigate the activation patterns of the quadriceps and hamstrings muscles with respect to the peak knee abduction moment. Design: Cross-sectional study. Setting: Neuromuscular research laboratory. Patients or Other Participants: Twenty-one recreationally active adults (11 women, 10 men). Main Outcome Measure(s): Volunteers performed 3 trials of a 100-cm forward hop. During the hop task, we recorded surface electromyographic data from the medial and lateral hamstrings and quadriceps and recorded lower extremity kinematics and kinetics. Lateral and medial quadriceps-to-hamstrings (Q?H) cocontraction indices, the ratio of medial-to-lateral Q?H cocontraction, normalized root mean square electromyographic data for medial and lateral quadriceps and hamstrings, and peak knee abduction moment were calculated and used in data analyses. Results: Overall cocontraction was lower in women than in men, whereas activation was lower in the medial than in the lateral musculature in both sexes (P < .05). The medial Q?H cocontraction index (R2 ?=? 0.792) accounted for a significant portion of the variance in the peak knee abduction moment in women (P ?=? .001). Women demonstrated less activation in the vastus medialis than in the vastus lateralis (P ?=? .49) and less activation in the medial hamstrings than in the lateral hamstrings (P ?=? .01). Conclusions: Medial-to-lateral Q?H cocontraction appears to be unbalanced in women, which may limit their ability to resist abduction loads. Because higher abduction loads increase strain on the ACL, restoring medial-to-lateral Q?H cocontraction balance in women may help reduce ACL injury risk. PMID:19478837

Palmieri-Smith, Riann M; McLean, Scott G; Ashton-Miller, James A; Wojtys, Edward M

2009-01-01

152

Spontaneous rupture of the quadriceps tendon and patellar ligament during treatment for chronic renal failure.  

PubMed Central

The quadriceps tendon and patellar ligament rupture rarely, even when under great stress or trauma, but can rupture spontaneously in patients with chronic diseases such as gout, rheumatoid arthritis and renal disease. Several factors probably combine to weaken the tendon, including an impoverished local vascular supply, repeated microtrauma and secondary hypoparathyroidism with osteodystrophy. In the three cases reported here, one of which was bilateral, the patients were being treated for chronic renal disease; surgical repair of the tendons led to sound healing and a return to normal function of the joints. PMID:6861063

Loehr, J.; Welsh, R. P.

1983-01-01

153

Improved Inflammatory Balance of Human Skeletal Muscle during Exercise after Supplementations of the Ginseng-Based Steroid Rg1  

PubMed Central

The purpose of the study was to determine the effect of ginseng-based steroid Rg1 on TNF-alpha and IL-10 gene expression in human skeletal muscle against exercise challenge, as well as on its ergogenic outcomes. Randomized double-blind placebo-controlled crossover trials were performed, separated by a 4-week washout. Healthy young men were randomized into two groups and received capsule containing either 5 mg of Rg1 or Placebo one night and one hour before exercise. Muscle biopsies were conducted at baseline, immediately and 3 h after a standardized 60-min cycle ergometer exercise. While treatment differences in glycogen depletion rate of biopsied quadriceps muscle during exercise did not reach statistical significance, Rg1 supplementations enhanced post-exercise glycogen replenishment and increased citrate synthase activity in the skeletal muscle 3 h after exercise, concurrent with improved meal tolerance during recovery (P<0.05). Rg1 suppressed the exercise-induced increases in thiobarbituric acids reactive substance (TBARS) and reversed the increased TNF-alpha and decreased IL-10 mRNA of quadriceps muscle against the exercise challenge. PGC-1 alpha and GLUT4 mRNAs of exercised muscle were not affected by Rg1. Maximal aerobic capacity (VO2max) was not changed by Rg1. However, cycling time to exhaustion at 80% VO2max increased significantly by ~20% (P<0.05). Conclusion: Our result suggests that Rg1 is an ergogenic component of ginseng, which can minimize unwanted lipid peroxidation of exercised human skeletal muscle, and attenuate pro-inflammatory shift under exercise challenge. PMID:25617625

Hou, Chien-Wen; Lee, Shin-Da; Kao, Chung-Lan; Cheng, I-Shiung; Lin, Yu-Nan; Chuang, Sheng-Ju; Chen, Chung-Yu; Ivy, John L.; Huang, Chih-Yang; Kuo, Chia-Hua

2015-01-01

154

Early Neuromuscular Electrical Stimulation to Improve Quadriceps Muscle Strength After Total Knee Arthroplasty: A Randomized Controlled Trial  

PubMed Central

Background The recovery of quadriceps muscle force and function after total knee arthroplasty (TKA) is suboptimal, which predisposes patients to disability with increasing age. Objective The purpose of this investigation was to evaluate the efficacy of quadriceps muscle neuromuscular electrical stimulation (NMES), initiated 48 hours after TKA, as an adjunct to standard rehabilitation. Design This was a prospective, longitudinal randomized controlled trial. Methods Sixty-six patients, aged 50 to 85 years and planning a primary unilateral TKA, were randomly assigned to receive either standard rehabilitation (control) or standard rehabilitation plus NMES applied to the quadriceps muscle (initiated 48 hours after surgery). The NMES was applied twice per day at the maximum tolerable intensity for 15 contractions. Data for muscle strength, functional performance, and self-report measures were obtained before surgery and 3.5, 6.5, 13, 26, and 52 weeks after TKA. Results At 3.5 weeks after TKA, significant improvements with NMES were found for quadriceps and hamstring muscle strength, functional performance, and knee extension active range of motion. At 52 weeks, the differences between groups were attenuated, but improvements with NMES were still significant for quadriceps and hamstring muscle strength, functional performance, and some self-report measures. Limitations Treatment volume was not matched for both study arms; NMES was added to the standard of care treatment. Furthermore, testers were not blinded during testing, but used standardized scripts to avoid bias. Finally, some patients reached the maximum stimulator output during at least one treatment session and may have tolerated more stimulation. Conclusions The early addition of NMES effectively attenuated loss of quadriceps muscle strength and improved functional performance following TKA. The effects were most pronounced and clinically meaningful within the first month after surgery, but persisted through 1 year after surgery. PMID:22095207

Balter, Jaclyn E.; Wolfe, Pamela; Eckhoff, Donald G.; Kohrt, Wendy M.

2012-01-01

155

The effects of hip muscle strengthening on knee load, pain, and function in people with knee osteoarthritis: a protocol for a randomised, single-blind controlled trial  

Microsoft Academic Search

BACKGROUND: Lower limb strengthening exercises are an important component of the treatment for knee osteoarthritis (OA). Strengthening the hip abductor and adductor muscles may influence joint loading and\\/or OA-related symptoms, but no study has evaluated these hypotheses directly. The aim of this randomised, single-blind controlled trial is to determine whether hip abductor and adductor muscle strengthening can reduce knee load

Kim L Bennell; Michael A Hunt; Tim V Wrigley; David J Hunter; Rana S Hinman

2007-01-01

156

Exercise Habit  

MedlinePLUS

... bicycle the next. Consider activities like dancing and racquet sports, and even chores like vacuuming or mowing the ... on a regular basis. How can I prevent injuries? To avoid injuring yourself during exercise, don’t ...

157

Seismological Exercises  

NSDL National Science Digital Library

This homework exercise, which was designed for an undergraduate level geology class at Tulane University, asks the student to make evaluations about the Loma Prieta Earthquake and other earthquakes using seismograms, time travel curves, maps and other information.

Nelson, Stephen

158

Treadmill Training Increases SIRT-1 and PGC-1? Protein Levels and AMPK Phosphorylation in Quadriceps of Middle-Aged Rats in an Intensity-Dependent Manner  

PubMed Central

The present study investigated the effects of running at 0.8 or 1.2?km/h on inflammatory proteins (i.e., protein levels of TNF-?, IL-1?, and NF-?B) and metabolic proteins (i.e., protein levels of SIRT-1 and PGC-1?, and AMPK phosphorylation) in quadriceps of rats. Male Wistar rats at 3 (young) and 18 months (middle-aged rats) of age were divided into nonexercised (NE) and exercised at 0.8 or 1.2?km/h. The rats were trained on treadmill, 50?min per day, 5 days per week, during 8 weeks. Forty-eight hours after the last training session, muscles were removed, homogenized, and analyzed using biochemical and western blot techniques. Our results showed that: (a) running at 0.8?km/h decreased the inflammatory proteins and increased the metabolic proteins compared with NE rats; (b) these responses were lower for the inflammatory proteins and higher for the metabolic proteins in young rats compared with middle-aged rats; (c) running at 1.2?km/h decreased the inflammatory proteins and increased the metabolic proteins compared with 0.8?km/h; (d) these responses were similar between young and middle-aged rats when trained at 1.2?km. In summary, the age-related increases in inflammatory proteins, and the age-related declines in metabolic proteins can be reversed and largely improved by treadmill training. PMID:25002755

Oliveira, Nara R. C.; Marques, Scherolin O.; Luciano, Thais F.; Pauli, José R.; Moura, Leandro P.; Caperuto, Erico; Pieri, Bruno L. S.; Engelmann, Julia; Scaini, Gisele; Streck, Emilio L.; Lira, Fabio S.; Pinho, Ricardo A.; Ropelle, Eduardo R.; Silva, Adelino S. R.; De Souza, Cláudio T.

2014-01-01

159

Treadmill training increases SIRT-1 and PGC-1 ? protein levels and AMPK phosphorylation in quadriceps of middle-aged rats in an intensity-dependent manner.  

PubMed

The present study investigated the effects of running at 0.8 or 1.2 km/h on inflammatory proteins (i.e., protein levels of TNF- ? , IL-1 ? , and NF- ? B) and metabolic proteins (i.e., protein levels of SIRT-1 and PGC-1 ? , and AMPK phosphorylation) in quadriceps of rats. Male Wistar rats at 3 (young) and 18 months (middle-aged rats) of age were divided into nonexercised (NE) and exercised at 0.8 or 1.2 km/h. The rats were trained on treadmill, 50 min per day, 5 days per week, during 8 weeks. Forty-eight hours after the last training session, muscles were removed, homogenized, and analyzed using biochemical and western blot techniques. Our results showed that: (a) running at 0.8 km/h decreased the inflammatory proteins and increased the metabolic proteins compared with NE rats; (b) these responses were lower for the inflammatory proteins and higher for the metabolic proteins in young rats compared with middle-aged rats; (c) running at 1.2 km/h decreased the inflammatory proteins and increased the metabolic proteins compared with 0.8 km/h; (d) these responses were similar between young and middle-aged rats when trained at 1.2 km. In summary, the age-related increases in inflammatory proteins, and the age-related declines in metabolic proteins can be reversed and largely improved by treadmill training. PMID:25002755

Oliveira, Nara R C; Marques, Scherolin O; Luciano, Thais F; Pauli, José R; Moura, Leandro P; Caperuto, Erico; Pieri, Bruno L S; Engelmann, Julia; Scaini, Gisele; Streck, Emilio L; Lira, Fabio S; Pinho, Ricardo A; Ropelle, Eduardo R; Silva, Adelino S R; De Souza, Cláudio T

2014-01-01

160

A stepwise procedure to test contractility and susceptibility to injury for the rodent quadriceps muscle  

PubMed Central

In patients with muscle injury or muscle disease, assessment of muscle damage is typically limited to clinical signs, such as tenderness, strength, range of motion, and more recently, imaging studies. Biological markers can also be used in measuring muscle injury, such as increased creatine kinase levels in the blood, but these are not always correlated with loss in muscle function (i.e. loss of force production). This is even true of histological findings from animals, which provide a “direct measure” of damage, but do not account for loss of function. The most comprehensive measure of the overall health of the muscle is contractile force. To date, animal models testing contractile force have been limited to the muscle groups moving the ankle. Here we describe an in vivo animal model for the quadriceps, with abilities to measure torque, produce a reliable muscle injury, and follow muscle recovery within the same animal over time. We also describe a second model used for direct measurement of force from an isolated quadriceps muscle in situ.

Pratt, Stephen J.P.; Lovering, Richard M.

2014-01-01

161

Simultaneous reconstruction of quadriceps tendon rupture after TKA and neglected Achilles tendon rupture.  

PubMed

We report a case of simultaneous reconstruction of a quadriceps tendon rupture after total knee arthroplasty (TKA) and neglected Achilles tendon rupture, which occurred before TKA with an ipsilateral hamstring autograft. A 64-year-old woman presented with persistent right knee pain. She also had right heel pain and had received multiple steroid injections at the knee joint and heel. On examination, she showed osteoarthritis in the medial and lateral compartments of the knee joint and an Achilles tendon rupture in the ipsilateral limb. There was skin dimpling and the proximal portion of tendon was migrated. We performed TKA, and the postoperative course was satisfactory. She returned 3 months postoperatively, however, with skin dimpling around the suprapatellar area and weakness of knee extension. Her ankle symptoms were also aggravated because she could not use the knee joint freely. We performed simultaneous reconstruction of the quadriceps tendon and the Achilles tendon using an ipsilateral hamstring autograft.Hamstring autograft offers a good alternative treatment option for rupture repair, particularly with concommitant ruptures of multiple sites when primary repair is not possible or the viability of repaired tissue is poor. PMID:20506939

Lee, Yong Seuk; Min, Byoung-Hyun; Han, Kyeong-Jin; Cho, Jae Ho; Han, Seung Hwan; Lee, Doo-Hyung; Oh, Kyung Soo

2010-05-01

162

Perceived exertion and maximal quadriceps femoris muscle strength during dynamic knee extension exercise in young adult males and females  

Microsoft Academic Search

  \\u000a The objectives of the present study were to: (1) examine perceived exertion across different target voluntary-contraction\\u000a intensities; (2) compare perceived exertion ratings with actual target intensities, and (3) compare perceived exertion ratings\\u000a between males and females. Subjects for this study included 30 healthy, college-aged male (n=15) and female (n=15) volunteers. All subjects were free of orthopedic, cardiopulmonary, systemic and

Danny M. Pincivero; Alan J. Coelho; Robert M. Campy

2003-01-01

163

Quadriceps Contusion  

MedlinePLUS

... lot of direct contact, such as football and hockey. They're also a risk in sports where ... play sports: Wear protective gear that fits correctly. Hockey and football require pants that should have thigh ...

164

The contribution of the medial retinaculum and quadriceps muscles to patellar lateral stability--an in-vitro study.  

PubMed

Patellofemoral joint stability is a result of the restraining effects of the quadriceps muscles, the retinacular structures, and engagement of the bones. The role and significance of these mechanisms in restraining patellar lateral displacement was investigated in this study by measuring the force needed to cause 5 mm lateral displacement (i.e. the mechanical stability, or 'stabilising force') of the patella. Six cadaver knees had 175 N quadriceps load distributed among three muscle groups. With a force ratio matching the muscles physiological cross sectional areas, no significant change occurred in the patellar stabilising force between 0 and 60 degrees knee flexion, but a significant increase occurred between 60 and 90 degrees, presumably reflecting the contribution of the femoral groove. Variation of the quadriceps force distribution changed the stability significantly. Relaxing the vastus lateralis increased the patellar lateral stabilising force 52+/-8%, while relaxing vastus medialis reduced the stabilising force 47+/-9%. The minimum stabilising force was at 30 degrees knee flexion. Transection of the medial retinaculum reduced the lateral stabilising force 34% in the extended knee. This effect disappeared by 45 degrees knee flexion. It was concluded that the quadriceps muscles had a significant and consistent effect across the whole range of knee flexion, but the contribution of the medial retinaculum was restricted to extended knee postures. PMID:15066616

Farahmand, Farzam; Naghi Tahmasbi, Mohammad; Amis, Andrew

2004-04-01

165

Comparison of Lower Body Specific Resistance Training on the Hamstring to Quadriceps Strength Ratios in Men and Women  

ERIC Educational Resources Information Center

In this study, we compared hamstring (H) and quadriceps (Q) strength changes in men and women, as well as changes in conventional and functional H:Q ratios following an identical 12-week resistance training program. An isokinetic dynamometer was used to assess 14 male and 14 female participants before and after the intervention, and conventional…

Dorgo, Sandor; Edupuganti, Pradeep; Smith, Darla R.; Ortiz, Melchor

2012-01-01

166

Expression of interleukin-15 in human skeletal muscle – effect of exercise and muscle fibre type composition  

PubMed Central

The cytokine interleukin-15 (IL-15) has been demonstrated to have anabolic effects in cell culture systems. We tested the hypothesis that IL-15 is predominantly expressed by type 2 skeletal muscle fibres, and that resistance exercise regulates IL-15 expression in muscle. Triceps brachii, vastus lateralis quadriceps and soleus muscle biopsies were obtained from normally physically active, healthy, young male volunteers (n= 14), because these muscles are characterized by having different fibre-type compositions. In addition, healthy, normally physically active male subjects (n= 8) not involved in any kind of resistance exercise underwent a heavy resistance exercise protocol that stimulated the vastus lateralis muscle and biopsies were obtained from this muscle pre-exercise as well as 6, 24 and 48 h post-exercise. IL-15 mRNA levels were twofold higher in the triceps (type 2 fibre dominance) compared with the soleus muscle (type 1 fibre dominance), but Western blotting and immunohistochemistry revealed that muscle IL-15 protein content did not differ between triceps brachii, quadriceps and soleus muscles. Following resistance exercise, IL-15 mRNA levels were up-regulated twofold at 24 h of recovery without any changes in muscle IL-15 protein content or plasma IL-15 at any of the investigated time points. In conclusion, IL-15 mRNA level is enhanced in skeletal muscles dominated by type 2 fibres and resistance exercise induces increased muscular IL-15 mRNA levels. IL-15 mRNA levels in skeletal muscle were not paralleled by similar changes in muscular IL-15 protein expression suggesting that muscle IL-15 may exist in a translationally inactive pool. PMID:17690139

Nielsen, Anders Rinnov; Mounier, Remi; Plomgaard, Peter; Mortensen, Ole Hartvig; Penkowa, Milena; Speerschneider, Tobias; Pilegaard, Henriette; Pedersen, Bente Klarlund

2007-01-01

167

Adaptive Force Regulation of Muscle Strengthening Rehabilitation Device With Magnetorheological Fluids  

PubMed Central

In rehabilitation from neuromuscular trauma or injury, strengthening exercises are often prescribed by physical therapists to recover as much function as possible. Strengthening equipment used in clinical settings range from low-cost devices, such as sandbag weights or elastic bands to large and expensive isotonic and isokinetic devices. The low-cost devices are incapable of measuring strength gains and apply resistance based on the lowest level of torque that is produced by a muscle group. Resistance that varies with joint angle can be achieved with isokinetic devices in which angular velocity is held constant and variable torque is generated when the patient attempts to move faster than the device but are ineffective if a patient cannot generate torque rapidly. In this paper, we report the development of a versatile rehabilitation device that can be used to strengthen different muscle groups based on the torque generating capability of the muscle that changes with joint angle. The device is low cost, is smaller than other commercially available machines, and can be programmed to apply resistance that is unique to a particular patient and that will optimize strengthening. The core of the device, a damper with smart magnetorheological fluids, provides passive exercise force. A digital adaptive control is capable of regulating exercise force precisely following the muscle strengthening profile prescribed by a physical therapist. The device could be programmed with artificial intelligence to dynamically adjust the target force profile to optimize rehabilitation effects. The device provides both isometric and isokinetic strength training and can be developed into a small, low-cost device that may be capable of providing optimal strengthening in the home. PMID:16562632

Dong, Shufang; Lu, Ke-Qian; Sun, Jian Qiao; Rudolph, Katherine

2008-01-01

168

MuRF-1 and Atrogin-1 Protein Expression and Quadriceps Fiber Size and Muscle Mass in Stable Patients with COPD  

PubMed Central

Introduction Animal studies demonstrate the importance of the E3 ubiquitin ligases, Muscle RING-Finger Protein 1 (MuRF-1) and atrogin-1, in muscle protein degradation during acute muscle atrophy. Small clinical studies suggest MuRF-1 and atrogin-1 expression in the quadriceps muscle is also increased in stable patients with Chronic Obstructive Pulmonary Disease compared to controls. However, it remains unclear whether these ligases have a role in maintaining a muscle-wasted state in COPD patients. Methods 32 stable COPD patients (16 with a low fat-free mass index (FFMI), 16 with a normal FFMI) and 15 controls underwent lung function and quadriceps strength tests and a percutaneous quadriceps biopsy. Quadriceps MuRF-1 and atrogin-1 protein were quantified with western blotting. Quadriceps fiber cross-sectional area (CSA) and fiber proportions were determined by immunohistochemistry on muscle sections. MuRF-1 and atrogin-1 levels were compared between COPD patients with and without a low FFMI, and between patients and controls, and correlations between MuRF-1 and atrogin-1 levels and quadriceps fiber CSA in the patients were investigated. Results Atrogin-1 protein levels were lower in patients than controls, but similar in patients with a low and normal FFMI. MuRF-1 levels did not differ between any groups. MuRF-1 and atrogin-1 levels were not associated with quadriceps fiber CSA or quadriceps strength in patients. Conclusions Chronic upregulation of ubiquitin ligases was not evident in the quadriceps muscle of stable COPD patients with a low muscle mass. This does not exclude the possibility of transient increases in ubiquitin ligases during acute catabolic episodes. PMID:23844868

Natanek, Samantha A.; Riddoch-Contreras, Joanna; Marsh, Gemma S.; Hopkinson, Nicholas S.; Moxham, John; Man, William D.-C.; Kemp, Paul R.; Polkey, Michael I.

2013-01-01

169

Burnishing Techniques Strengthen Hip Implants  

NASA Technical Reports Server (NTRS)

In the late 1990s, Lambda Research Inc., of Cincinnati, Ohio, received Small Business Innovation Research (SBIR) awards from Glenn Research Center to demonstrate low plasticity burnishing (LPB) on metal engine components. By producing a thermally stable deep layer of compressive residual stress, LPB significantly strengthened turbine alloys. After Lambda patented the process, the Federal Aviation Administration accepted LPB for repair and alteration of commercial aircraft components, the U.S. Department of Energy found LPB suitable for treating nuclear waste containers at Yucca Mountain. Data from the U.S. Food and Drug Administration confirmed LPB to completely eliminate the occurrence of fretting fatigue failures in modular hip implants.

2010-01-01

170

Flooding Exercises  

NSDL National Science Digital Library

This homework exercise, developed for an undergraduate geology course at Tulane University, leads students through the steps involved in determining the probability that a flood of a given discharge will occur in any given year. Students retrieve discharge data from U.S. Geological Services Internet sites for Dry Creek, LA, Rapid Creek, SD and Red River, ND to make their calculations.

Nelson, Stephen

171

Exercise apparatus  

NASA Technical Reports Server (NTRS)

An apparatus and method for exercising whereby the user is supported by various mechanisms in such as way that the user's shoulder area is free to translate and rotate; the user's pelvic area is free to translate and rotate; or in any combination.

Schaffner, Grant (Inventor); Bentley, Jason R. (Inventor); Loehr, James A. (Inventor); Gundo, Daniel P. (Inventor)

2006-01-01

172

DTI-based muscle fiber tracking of the quadriceps mechanism in lateral patellar dislocation  

PubMed Central

Purpose To determine the feasibility of utilizing diffusion tensor MRI (DT-MRI) based muscle fiber tracking to create biomechanical models of the quadriceps mechanism in healthy subjects and those with chronic lateral patellar dislocation (LPD). Materials and Methods Four healthy (average 14.5 years old; BMI 21.8) and four chronic LPD (average 17.3 years old; BMI 22.4) females underwent DT and axial T1W MRI of the thighs. The anatomical and physiologic cross sectional areas (ACSA and PCSA, respectively) and pennation angle were calculated of the vastus lateralis oblique (VLO) and vastus medialis oblique (VMO) muscles. The predicted resultant force vector on the patella was calculated. Results The VLO pennation angles in healthy and LPD subjects were 18.7 and 14.5°, respectively (p=0.141). The VMO pennation angles in healthy and LPD subjects were 11.4 and 14.8°, respectively (p=0.02). The ACSA and PCSA VLO:VMO ratios in healthy and LPD subjects were 1.9:1.6 and 2.1:1.6, respectively (p=0.025 and 0.202, respectively). Regardless of whether ACSA or PCSA was used to predict resultant lateral force vectors, the values differed between healthy and LPD subjects (~2 and ~5.3°, respectively; p<0.05). Conclusion Chronic LPD patients had more laterally directed predicted resultant force vectors than healthy subjects. Our preliminary results suggest that biomechanical models of the quadriceps mechanism in patients with chronic LPD and healthy subjects can be created in healthy subjects and patients with chronic LPD using DT-MRI. PMID:19243049

Kan, J. Herman; Heemskerk, Anneriet M.; Ding, Zhaohua; Gregory, Andrew; Mencio, Gregory; Spindler, Kurt; Damon, Bruce M

2009-01-01

173

An Artificial Tendon to Connect the Quadriceps Muscle to the Tibia  

PubMed Central

No permanent, reliable artificial tendon exists clinically. Our group developed the OrthoCoupler™ device as a versatile connector, fixed at one end to a muscle, and adaptable at the other end to inert implants such as prosthetic bones or to bone anchors. The objective of this study was to evaluate four configurations of the device to replace the extensor mechanism of the knee in goats. Within muscle, the four groups had: (A) needle-drawn uncoated bundles, (B) needle-drawn coated bundles, (C) barbed uncoated bundles, and (D) barbed coated bundles. The quadriceps tendon, patella, and patellar tendon were removed from the right hind limb in 24 goats. The four groups (n=6 for each) were randomly assigned to connect the quadriceps muscle to the tibia (with a bone plate). Specimens were collected from each operated leg and contralateral unoperated controls both for mechanical testing and histology at 90 days post-surgery. In strength testing, maximum forces in the operated leg (vs. unoperated control) were 1288±123 N (vs. 1387±118 N) for group A, 1323±144 N (vs. 1396±779 N) for group B, 930±125 N (vs. 1337±126 N) for group C, and 968±109 N (vs. 1528±146 N) for group D (mean ± SEM). The strengths of the OrthoCoupler™ legs in the needled device groups were equivalent to unoperated controls (p=0.6), while both barbed device groups had maximum forces significantly lower than their controls (p=0.001). We believe this technology will yield improved procedures for clinical challenges in orthopaedic oncology, revision arthroplasty, tendon transfer, and tendon injury reconstruction. PMID:21520259

Melvin, Alan; Litsky, Alan; Mayerson, Joel; Stringer, Keith; Melvin, David; Juncosa-Melvin, Natalia

2011-01-01

174

Effect of Exercise Speed and Isokinetic Feedback on the Middle and Lower Serratus Anterior Muscles during Push-up Exercises.  

PubMed

[Purpose] This study assessed the use of different exercise speeds and isokinetic feedback on the middle and lower serratus anterior muscles during push-up exercises. [Subjects] Ten male workers voluntarily consented to participate in the study. [Methods] The subjects performed push-up exercises under three conditions. Surface electrodes were placed on the dominant right side of the middle and lower serratus anterior muscles. [Results] The middle and lower SA muscle activities under condition 2 were significantly decreased when compared with those under conditions 1 and 3. The middle SA activity under condition 3 was significantly increased when compared with that under condition 1. [Conclusion] This study suggests that proper selection of push-up exercise speed may be necessary for selective strengthening of the SA and that isokinetic feedback information obtained using an accelerator can help in selective strengthening of the middle SA. PMID:24926123

Yoo, Won-Gyu

2014-05-01

175

Exercise prescriptions to prevent musculoskeletal disorders in dentists.  

PubMed

Since the number of dental patients is increasing day by day dentists are forced to spend longer times in dental chairs. This is increasing the prevalence of musculoskeletal disorders in dentists. This article reviews the mechanisms causing musculoskeletal disorders among dentists and also covers the exercises that can be done to prevent them. Exercises that increase the fitness of a dentist are divided into aerobic exercises - concentrating on total body fitness, stretching exercises - that concentrate on the muscles that tend to tighten in prolonged dental postures and strengthening exercises - that concentrate on the muscles that are opposite to the tight muscles. These exercises are made simple and of minimal intensity so that a dentist can practice them independently. PMID:25177661

Kumar, Dodda Kiran; Rathan, Neelima; Mohan, Sreevalli; Begum, Mohammadi; Prasad, Bhanu; Prasad, Eswar Ravi Vara

2014-07-01

176

Noninvasive detection of change in skeletal muscle oxygenation during incremental exercise with near-infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Near infrared spectroscopy (NIRS) has been developed as a non-invasive method to assess O2 delivery, O2 consumption and blood flow, in diverse local muscle groups at rest and during exercise. The aim of this study was to investigate local O2 consumption in exercising muscle by use of near-infrared spectroscopy (NIRS). Ten elite athletes of different sport items were tested in rest and during step incremental load exercise. Local variations of quadriceps muscles were investigated with our wireless NIRS blood oxygen monitor system. The results show that the changes of blood oxygen relate on the sport items, type of muscle, kinetic capacity et al. These results indicate that NIRS is a potential useful tool to detect local muscle oxygenation and blood flow profiles; therefore it might be easily applied for evaluating the effect of athletes training.

Liu, Fang; Luo, Qingming; Xu, Guodong; Li, Pengcheng

2003-12-01

177

Adherence of older women with strength training and aerobic exercise  

PubMed Central

Background Participation of older people in a program of regular exercise is an effective strategy to minimize the physical decline associated with age. The purpose of this study was to assess adherence rates in older women enrolled in two different exercise programs (one aerobic exercise and one strength training) and identify any associated clinical or functional factors. Methods This was an exploratory observational study in a sample of 231 elderly women of mean age 70.5 years. We used a structured questionnaire with standardized tests to evaluate the relevant clinical and functional measures. A specific adherence questionnaire was developed by the researchers to determine motivators and barriers to exercise adherence. Results The adherence rate was 49.70% in the aerobic exercise group and 56.20% in the strength training group. Multiple logistic regression models for motivation were significant (P=0.003) for the muscle strengthening group (R2=0.310) and also significant (P=0.008) for the aerobic exercise group (R2=0.154). A third regression model for barriers to exercise was significant (P=0.003) only for the muscle strengthening group (R2=0.236). The present study shows no direct relationship between worsening health status and poor adherence. Conclusion Factors related to adherence with exercise in the elderly are multifactorial. PMID:24600212

Picorelli, Alexandra Miranda Assumpção; Pereira, Daniele Sirineu; Felício, Diogo Carvalho; Dos Anjos, Daniela Maria; Pereira, Danielle Aparecida Gomes; Dias, Rosângela Corrêa; Assis, Marcella Guimarães; Pereira, Leani Souza Máximo

2014-01-01

178

Differences in Neuromuscular Control and Quadriceps Morphology Between Potential Copers and Noncopers Following Anterior Cruciate Ligament Injury  

PubMed Central

Study Design Prospective cross-sectional study. Objectives To compare knee muscle morphology and voluntary neuromuscular control in individuals who sustained an anterior cruciate ligament (ACL) injury and were identified as being capable of avoiding surgery (potential copers) and those who were recommended for surgery (noncopers), within 6 months of injury. Background Quadriceps atrophy and poor neuromuscular control have been found in noncopers. However, the reasons why some noncopers may be able to avoid surgery remain elusive. Methods Twenty participants (10 ACL-deficient noncopers and 10 ACL-deficient potential copers) were included in this study. Axial spin-echo, T1-weighted magnetic resonance imaging data of the lower extremities were captured. The volume and maximum cross-sectional area (CSA) of each muscle of the quadriceps and hamstrings were calculated following digital reconstruction. In addition, voluntary neuromuscular control was evaluated using an established target-matching task that required participants to produce static isometric loads across the knee joint. Electromyography was acquired from 5 muscles as participants performed the target-matching task. Circular statistics were used to calculate a specificity index to describe how well focused each muscle was activated toward its primary direction of muscle action. The ACL-deficient limb was then compared to the uninvolved limb of the noncopers and potential copers. Results The vasti (vastus medialis and vastus intermedius) of the involved limb of the noncopers were significantly smaller (P<.031) in comparison to those of their uninvolved limb. The potential copers' vastus lateralis maximum CSA (P = .047), total quadriceps muscle volume (P = .020) and maximum CSA (P = .015), and quadriceps-hamstring ratio volume (P = .021) and maximum CSA (P = .007) demonstrated quadriceps atrophy. However, only the ACL-deficient limb of the older (mean ± SD age, 27.4 ± 11.4 versus 19.9 ± 3.3 years; P = .032) and lower-activity-level (3.3 ± 0.5 versus 3.6 ± 0.5; P = .098) noncoper group demonstrated reduced rectus femoris (P = .057) and lateral hamstring (P = .064) neuromuscular control in comparison to their uninvolved limb. Conclusion These findings suggest that quadriceps and hamstring muscle function, rather than muscle size, may be an important factor in the varied response early after ACL injury. PMID:24261930

Macleod, Toran D.; Snyder-Mackler, Lynn; Buchanan, Thomas S.

2015-01-01

179

Real-time noninvasive optical imaging of exercising muscle and brain upon cognitive stimuli  

NASA Astrophysics Data System (ADS)

The monitoring of a single muscle location does not reflect the heterogeneity of the muscle groups activation during exercise. In the past, measurements of oxygen consumption (VO2) at single muscle locations could be carried out non-invasively by near-infrared continuous wave spectroscopy (NIRCWS) at rest or during isometric contractions. In the present study, human regional quadriceps (vastus lateralis and rectus femoris) VO2 was investigated at rest and during maximal voluntary contractions using a 12- channel NIRCWS system with an acquisition time of 0.1 s.

Quaresima, Valentina; van der Sluijs, Marco C.; Menssen, Jan; Grillotti, Lucia; Ferrari, Marco; Colier, Willy N.

2001-06-01

180

Effects of endurance training and acute exhaustive exercise on antioxidant defense mechanisms in rat heart  

Microsoft Academic Search

We investigated whether 8-week treadmill training strengthens antioxidant enzymes and decreases lipid peroxidation in rat heart. The effects of acute exhaustive exercise were also investigated. Male rats (Rattus norvegicus, Sprague-Dawley strain) were divided into trained and untrained groups. Both groups were further divided equally into two groups where the rats were studied at rest and immediately after exhaustive exercise. Endurance

Mustafa Gul; Berna Demircan; Seyithan Taysi; Nuray Oztasan; Kenan Gumustekin; Erdinc Siktar; M. Fevzi Polat; Sedat Akar; Fatih Akcay; Senol Dane

2006-01-01

181

Validity and reliability of isometric, isokinetic and isoinertial modalities for the assessment of quadriceps muscle strength in patients with total knee arthroplasty.  

PubMed

Reliability of isometric, isokinetic and isoinertial modalities for quadriceps strength evaluation, and the relation between quadriceps strength and physical function was investigated in 29 total knee arthroplasty (TKA) patients, with an average age of 63 years. Isometric maximal voluntary contraction torque, isokinetic peak torque, and isoinertial one-repetition maximum load of the involved and uninvolved quadriceps were evaluated as well as objective (walking parameters) and subjective physical function (WOMAC). Reliability was good and comparable for the isometric, isokinetic, and isoinertial strength outcomes on both sides (intraclass correlation coefficient range: 0.947-0.966; standard error of measurement range: 5.1-9.3%). Involved quadriceps strength was significantly correlated to walking speed (r range: 0.641-0.710), step length (r range: 0.685-0.820) and WOMAC function (r range: 0.575-0.663), independent from the modality (P < 0.05). Uninvolved quadriceps strength was also significantly correlated to walking speed (r range: 0.413-0.539), step length (r range: 0.514-0.608) and WOMAC function (r range: 0.374-0.554) (P < 0.05), except for WOMAC function/isokinetic peak torque (P > 0.05). In conclusion, isometric, isokinetic, and isoinertial modalities ensure valid and reliable assessment of quadriceps muscle strength in TKA patients. PMID:24113423

Lienhard, K; Lauermann, S P; Schneider, D; Item-Glatthorn, J F; Casartelli, N C; Maffiuletti, N A

2013-12-01

182

Orthostasis: exercise and exercise training  

NASA Technical Reports Server (NTRS)

There are two major problems here that are not independent. One is the more practically oriented problem of determining the effect of various modes of exercise training on gravitational tolerances, i.e., the point of syncope (unconsciousness) usually estimated from the time of appearance of presyncopal signs and symptoms. The other is more theoretical and concerns the mechanism of blood pressure failure that results in syncope. In many experimental designs these two problems or purposes have been intermingled, with equivocal results.

Geelen, G.; Greenleaf, J. E.

1993-01-01

183

Decision rules for egg recognition are related to functional roles and chemical cues in the queenless ant Dinoponera quadriceps  

NASA Astrophysics Data System (ADS)

The capacity to distinguish colony members from strangers is a key component in social life. In social insects, this extends to the brood and involves discrimination of queen eggs. Chemical substances communicate colony affiliation for both adults and brood; thus, in theory, all colony members should be able to recognize fellow nestmates. In this study, we investigate the ability of Dinoponera quadriceps workers to discriminate nestmate and non-nestmate eggs based on cuticular hydrocarbon composition. We analyzed whether cuticular hydrocarbons present on the eggs provide cues of discrimination. The results show that egg recognition in D. quadriceps is related to both age and the functional role of workers. Brood care workers were able to distinguish nestmate from non-nestmate eggs, while callow and forager workers were unable to do so.

Tannure-Nascimento, Ivelize C.; Nascimento, Fabio S.; Dantas, José O.; Zucchi, Ronaldo

2009-07-01

184

Exercise and Compulsive Behavior.  

ERIC Educational Resources Information Center

Although reports on the positive effects of fitness and exercise predominate in the exercise literature, some researchers describe frequent exercise as compulsive or addictive behavior. This paper addresses these "negative addictions" of exercise. As early as 1970, researchers recognized the addictive qualities of exercise. Short-term studies on…

Polivy, Janet; Clendenen, Vanessa

185

Vitamin D deficiency associates with ?-tocopherol and quadriceps weakness but not inflammatory cytokines in subjects with knee osteoarthritis  

PubMed Central

Knee osteoarthritis (OA) is a degenerative joint condition and a leading cause of physical disability in the United States. Quadriceps weakness and inflammatory cytokines contribute to the pathogenesis of knee OA, and both of which, increase with vitamin D deficiency. Other micronutrients, such as vitamins C and E and ?-carotene, modulate inflammatory cytokines and decrease during inflammation. The purpose of this study was to test the hypothesis that vitamin D deficiency associates with quadriceps weakness, an increase in serum cytokines, and a decrease in circulating micronutrients in subjects with knee OA. Subjects (age, 48±1 y; serum 25(OH)D, 25.8±1.1 ng/mL) with knee OA were categorized as vitamin D deficient (n=17; serum 25(OH)D?20 ng/mL), insufficient (n=21; serum 25(OH)D 20–29 ng/mL), or sufficient (n=18; serum 25(OH)D?30 ng/mL). Single-leg strength (concentric knee extension–flexion contraction cycles at 60 °/s) and blood cytokine, carotene (? and ?), ascorbic acid, and tocopherol (? and ?) concentrations were measured. Quadriceps peak torque, average power, total work, and deceleration were significantly (all p<0.05) impaired with vitamin D deficiency. Serum ?-tocopherol concentrations were significantly (p<0.05) increased with vitamin D deficiency. In the vitamin D sufficient group, ?-tocopherol inversely correlated (r=?0.47, p<0.05) with TNF-?, suggesting a pro-inflammatory increase with a ?-tocopherol decrease despite a sufficient serum 25(OH)D concentration. We conclude that vitamin D deficiency is detrimental to quadriceps function, and in subjects with vitamin D sufficiency, ?-tocopherol could have an important anti-inflammatory role in a pathophysiological condition mediated by inflammation. PMID:24624336

Barker, Tyler; Henriksen, Vanessa T.; Rogers, Victoria E.; Aguirre, Dale; Trawick, Roy H.; Lynn Rasmussen, G.; Momberger, Nathan G.

2014-01-01

186

The importance of quadriceps and hamstring muscle loading on knee kinematics and in-situ forces in the ACL  

Microsoft Academic Search

This study investigated the effect of hamstring co-contraction with quadriceps on the kinematics of the human knee joint and the in-situ forces in the anterior cruciate ligament (ACL) during a simulated isometric extension motion of the knee. Cadaveric human knee specimens (n=10) were tested using the robotic\\/universal force–moment sensor (UFS) system and measurements of knee kinematics and in-situ forces in

G Li; T. W Rudy; M Sakane; A Kanamori; C. B Ma; S. L.-Y Woo

1999-01-01

187

Effect of pain reduction on postural sway, proprioception, and quadriceps strength in subjects with knee osteoarthritis  

PubMed Central

Objective: To investigate whether alleviation of knee pain influences quadriceps function, proprioceptive acuity, and postural stability in patients with knee osteoarthritis (OA). Methods: A crossover, within-subject, double blind study design involving 68 subjects with painful knee OA. Each subject received an intra-articular injection into one or both knees (both if symptomatic) of either 5 ml 0.5% bupivacaine or 5 ml 0.9% saline. Two weeks later they received an injection of the alternative agent. Subjects and observer were unaware of the order of injection, which was randomly assigned. Knee pain (100 mm visual analogue scale), static postural sway, knee proprioceptive acuity, maximum voluntary contraction (MVC), and percentage activation of the quadriceps were assessed immediately before and one hour after each injection. Results: Significant pain reduction was achieved one hour post-bupivacaine (mean difference as a percentage change 56.85, 95% CI 31.01 to 73.65; p<0.001) and post-saline (mean difference as a percentage change 41.94, 95% CI 11.57 to 76.66; p< 0.001), with no significant difference between the two. Both MVC and activation increased significantly post-bupivacaine (mean percentage differences 18.83, 95% CI -31.79 to -0.26, and -11.90, 95% CI -39.53 to 2.97, respectively; both p<0.001) and post-saline (mean percentage differences -7.64, 95% CI -21.96 to 4.73, and -10.71, 95% CI -25.19 to 2.60 respectively; both p<0.001). Proprioception worsened after bupivacaine (mean percentage difference -28.15%, 95% CI -83.47 to 19.74; p=0.009), but there was no effect on postural sway; saline injection had no effects. There was no order effect, and comparison of median percentage changes showed no significant differences between injections for change in MVC, activation, proprioception, or sway. Conclusion: Reduction in knee pain through either peripheral (local anaesthetic) or central (placebo) mechanisms resulted in increased MVC. This increase, however, did not result in improvements in proprioception or static postural stability, suggesting that other mechanisms play a part in these functions, at least in this acute model. PMID:11959766

Hassan, B; Doherty, S; Mockett, S; Doherty, M

2002-01-01

188

Angle-specific hamstring-to-quadriceps ratio: A comparison of football players and recreationally active males.  

PubMed

Abstract It is currently unclear how football participation affects knee-joint muscle balance, which is widely considered a risk factor for hamstrings injury. This study compared the angle-specific functional hamstring-to-quadriceps (H:Q) ratio (hamstrings eccentric torque as a ratio of quadriceps concentric torque at the same knee-joint angle) of football players with recreationally active controls. Ten male footballers and 14 controls performed maximal voluntary isometric and isovelocity concentric and eccentric contractions (60, 240 and 400° s(-1)) of the knee extensors and flexors. Gaussian fitting to the raw torque values was used to interpolate torque values for knee-joint angles of 100-160° (60° s(-1)), 105-160° (240° s(-1)) and 115-145° (400° s(-1)). The angle-specific functional H:Q ratio was calculated from the knee flexors eccentric and knee extensors concentric torque at the same velocity and angle. No differences were found for the angle-specific functional H:Q ratio between groups, at any velocity. Quadriceps and hamstrings strength relative to body mass of footballers and controls was similar for all velocities, except concentric knee flexor strength at 400° s(-1) (footballers +40%; P < 0.01). In previously uninjured football players, there was no intrinsic muscle imbalance and therefore the high rate of hamstring injuries seen in this sport may be due to other risk factors and/or simply regular exposure to a high-risk activity. PMID:25073098

Evangelidis, Pavlos Eleftherios; Pain, Matthew Thomas Gerard; Folland, Jonathan

2015-02-01

189

Assessment of quadriceps muscle weakness in patients after total knee arthroplasty and total hip arthroplasty: methodological issues.  

PubMed

The aim of this exploratory study was to verify whether the evaluation of quadriceps muscle weakness is influenced by the testing modality (isometric vs. isokinetic vs. isoinertial) and by the calculation method (within-subject vs. between-subject comparisons) in patients 4-8months after total knee arthroplasty (TKA, n=29) and total hip arthroplasty (THA, n=30), and in healthy controls (n=19). Maximal quadriceps strength was evaluated as (1) the maximal voluntary contraction (MVC) torque during an isometric contraction, (2) the peak torque during an isokinetic contraction, and (3) the one repetition maximum (1-RM) load during an isoinertial contraction. Muscle weakness was calculated as the difference between the involved and the uninvolved side (within-subject comparison) and as the difference between the involved side of patients and controls (between-subject comparison). Muscle weakness estimates were not significantly affected by the calculation method (within-subject vs. between-subject; P>0.05), whereas a significant main effect of testing modality (P<0.05) was observed. Isometric MVC torque provided smaller weakness estimates than isokinetic peak torque (P=0.06) and isoinertial 1-RM load (P=0.008), and the clinical occurrence of weakness (proportion of patients with large strength deficits) was also lower for MVC torque. These results have important implications for the evaluation of quadriceps muscle weakness in TKA and THA patients 4-8months after surgery. PMID:24290027

Lauermann, S P; Lienhard, K; Item-Glatthorn, J F; Casartelli, N C; Maffiuletti, N A

2014-04-01

190

Muscle ultrastructural changes from exhaustive exercise performed after prolonged restricted activity and retraining in dogs  

NASA Technical Reports Server (NTRS)

The effect of exhaustive treadmill exercise on ultrastructural changes in the quadriceps femoris muscle was studied in 7 normal, healthy dogs, before and after restricted activity (RA), and following a subsequent 2 month treadmill exercise retraining period for the 5 mo group. Mean time to exhaustion in the 2 mo group decreased from 177 + or - 22 min before to 90 + or - 32 min after RA. Retraining increased tolerance to 219 + or - 73 min; 24 pct. above the before RA and 143 pct. above the after RA time. After RA exhaustion time in the 5 mo group was 25 and 45 min. Before RA, pre-exercise muscle structure was normal and post exercise there was only slight swelling of mitochondria. After RA, pre-exercise, numerous glycogen granules and lipid droplets appeared in the muscle fibers, mitochondria were smaller, and sarcoplasmic reticulum channels widened; post exercise these changes were accentuated and some areas were devoid of glycogen, and there was fiber degradation. After 5 mo RA pre-exercise there were more pronounced changes; mitochondria were very small and dense, there were many lipid droplets, myofibrils were often separated, and the fibers appeared edematous and degenerating; post exercise the sarcoplasmic reticulum was swollen, no glycogen was present, and there was marked swelling and deformation of mitochondria. After retraining, both pre-exercise and post exercise there was still evidence of fiber degeneration. Thus, susceptibility of active skeletal muscle structures and subcellular elements, e.g., mitochondria, to the action of damaging factors occurring during exhaustive exercise is enhanced considerably by prolonged disuse.

Nazar, K.; Greenleaf, J. E.; Philpott, D.; Pohoska, E.; Olszewska, K.; Kaciuba-Uscilko, H.

1991-01-01

191

Isokinetic concentric quadriceps and hamstring normative data for elite collegiate American football players participating in the NFL Scouting Combine.  

PubMed

Isokinetic concentric quadriceps and hamstring strength data using a Cybex dynamometer are collected for elite collegiate American football players invited to the annual National Football League Scouting Combine. We constructed a normative (reference) database of the Cybex strength data for the purpose of allowing comparison of an individual's values to his peers. Data reduction was performed to construct frequency distributions of hamstring/quadriceps (H/Q) ratios and side-to-side strength differences. For the cohort (n = 1,252 players), a statistically significant but very small (1.9%) mean quadriceps strength preference existed for dominant side vs. nondominant side. Peak torque (Newton meters, best repetition) for quadriceps and hamstrings was significantly correlated to player body mass (weight) (the same relationship was found for other variables using peak torque in the calculation). Peak torque varied by player position, being greatest for offensive linemen and lowest for kickers (p < 0.0001). Adjusting for body weight overcorrected these differences. The H/Q ratios and frequency distributions were similar across positions, with a mean of 0.6837 ± 0.137 for the cohort dominant side vs. 0.6940 ± 0.145 for the nondominant side (p = 0.021, n = 1,252). Considerable variation was seen for dominant-to-nondominant side difference for peak torque. For quadriceps, 47.2% of players had differences between -10% and +10%, 21.0% had a peak torque dominant-side deficit of 10% or greater compared to nondominant side, and for 31.8% of players, dominant-side peak torque was greater than 10% compared to nondominant side. For hamstrings, 57.0% of players had differences between -10% and +10%, 19.6% had a peak torque dominant-side deficit of 10% or greater compared to nondominant side, and 23.4% of players, dominant-side peak torque was greater than 10% compared to nondominant side. We observed that isokinetic absolute strength variables are dependent on body weight and vary across player position. The H/Q ratios vary only within a relatively narrow range. Side-to-side differences in strength variables >10% are common, not the exception. PMID:23820564

Zvijac, John E; Toriscelli, Todd A; Merrick, W Shannon; Papp, Derek F; Kiebzak, Gary M

2014-04-01

192

Hamstrings-to-quadriceps strength and size ratios of male professional soccer players with muscle imbalance.  

PubMed

The aim of this study was to determine the correlation between the concentric hamstrings/quadriceps muscle strength (Hcon :Qcon ) and cross-sectional area ratios (Hcsa :Qcsa ) in professional soccer players with Hcon :Qcon imbalance. Nine male professional soccer players (25·3 ± 4·1 years) performed five maximal concentric contractions of the knee extensors (KE) and flexors (KF) at 60 s(-1) to assess Hcon :Qcon . The test was performed using the dominant (preferred kicking), and non-dominant limb with a 5-min recovery period was allowed between them. Only players with Hcon :Qcon  < 0·60 (range: 0·45-0·59) in both limbs were included in this study. The muscle cross-sectional area (CSA) of KE and KF was determined by magnetic resonance imaging. The correlations between Hcon :Qcon and Hcsa :Qcsa in the dominant leg (r = -0·33), non-dominant leg (r = 0·19) and in the both legs combined (r = 0·28) were not statistically significant (P>0·05). Thus, the Hcon :Qcon seems not to be determined by Hcsa :Qcsa in professional soccer players with Hcon :Qcon imbalance. PMID:25348722

Denadai, Benedito Sérgio; de Oliveira, Felipe Bruno Dias; Camarda, Sérgio Ricardo de Abreu; Ribeiro, Leandro; Greco, Camila Coelho

2014-10-27

193

Alterations in quadriceps and hamstrings coordination in persons with medial compartment knee osteoarthritis  

PubMed Central

Altered muscle coordination strategies in persons with knee osteoarthritis (OA) result in an increase in co-contraction of the quadriceps and hamstrings during walking. While this may increase intersegmental joint contact force and expedite disease progression, it is not currently known whether the magnitude of co-contraction increases with a progressive loss of joint space or whether the level of co-contraction is dependent on walking speed. The purposes of this study were to (1) determine if co-contraction increased with OA severity and (2) discern whether differences in co-contraction were a result of altered freely chosen walking speeds or rather an inherent change associated with disease progression. Forty-two subjects with and without knee osteoarthritis were included in the study. Subjects were divided into groups based on disease severity. When walking at a controlled speed of 1.0 m/s, subjects with moderate and severe knee OA showed significantly higher co-contraction when compared to a healthy control group. At freely chosen walking speeds only the moderate OA group had significantly higher co-contraction values. Increased walking speed also resulted in a significant increase in co-contraction, regardless of group. The results of this study demonstrate that persons with knee OA develop higher antagonistic muscle activity. This occurs despite differences in freely chosen walking speed. Although subjects with OA had higher co-contraction than the control group, co-contraction may not increase with disease severity. PMID:19223203

Zeni, Joseph A.; Rudolph, Katherine; Higginson, Jill S.

2009-01-01

194

Effects of supplemental carbohydrate ingestion during superimposed electromyostimulation exercise in elite weightlifters.  

PubMed

The purpose of this investigation was to test the effects of carbohydrate supplementation on blood parameters and force output during superimposed electromyostimulation (SEMS) single-leg isometric contractions. We hypothesized that carbohydrate ingestion before and during muscle contractions would lead to greater glucose availability and greater total force output for the session. Six elite resistance trained male subjects participated in a randomized, counterbalanced, double-blind study. The subjects were randomly assigned to placebo (PL) or carbohydrate (CHO). The subjects in CHO consumed 1 g of carbohydrate per kilogram of body mass loading dose and 0.17 g of carbohydrate · per kilogram of body mass every 6 minutes during the exercise protocol. The PL received an equal volume of a solution made of saccharin and aspartame. The exercise protocol consisted of repeated 20-second isometric contractions of quadriceps muscle at 50% maximal voluntary contraction followed by 40 seconds of rest until failure occurred. Importantly, quadriceps maximal voluntary contraction with SEMS was performed in the beginning and then every 5 minutes during the last 3 seconds of isometric contractions throughout the exercise protocol. Venous blood samples were taken preexercise, immediately postexercise, and at 5 minutes postexercise and analyzed for glucose, nonesterified fatty acids, and glycerol. Our results indicate that CHO ingestion increased (p < 0.05) plasma glucose, but no significant differences (p > 0.05) were detected for nonesterified fatty acids or glycerol. Importantly, total force output during exercise protocol was higher (p < 0.05) in CHO compared with that in PL. Therefore, our data suggest that CHO supplementation before and during exercise may be beneficial for individuals performing high-volume resistance training. PMID:23442284

Wax, Benjamin; Kavazis, Andreas N; Brown, Stanley P

2013-11-01

195

Exercising with Osteoarthritis  

MedlinePLUS

... everyone. In fact, studies show that people with osteoarthritis benefit from regular exercise and physical activity. For people with osteoarthritis, regular exercise can help: l Maintain healthy and ...

196

Lifelong exercise and locally produced insulin-like growth factor-1 (IGF-1) have a modest influence on reducing age-related muscle wasting in mice.  

PubMed

The age-related loss of skeletal muscle mass and function is termed sarcopenia and has been attributed to a decline in concentrations of insulin-like growth factor-1 (IGF-1). We hypothesized that constitutively expressed IGF-1 within skeletal muscles with or without exercise would prevent sarcopenia. Male transgenic mice that overexpress IGF-1 Ea in skeletal muscles were compared with wild-type littermates. Four-month-old mice were assigned to be sedentary, or had access to free-running wheels, until 18 or 28 months of age. In wild-type mice, the mass of the quadriceps muscles was reduced at 28 months and exercise prevented such loss, without affecting the diameter of myofibers. Conversely, increased IGF-1 alone was ineffective, whereas the combination of exercise and IGF-1 was additive in maintaining the diameter of myofibers in the quadriceps muscles. For other muscles, the combination of IGF-1 and exercise was variable and either increased or decreased the mass at 18 months of age, but was ineffective thereafter. Despite an increase in the diameter of myofibers, grip strength was not improved. In conclusion, our data show that exercise and IGF-1 have a modest effect on reducing aged-related wasting of skeletal muscle, but that there is no improvement in muscle function when assessed by grip strength. PMID:24814689

McMahon, C D; Chai, R; Radley-Crabb, H G; Watson, T; Matthews, K G; Sheard, P W; Soffe, Z; Grounds, M D; Shavlakadze, T

2014-12-01

197

Resistance Versus Aerobic Exercise  

PubMed Central

OBJECTIVE In type 1 diabetes, small studies have found that resistance exercise (weight lifting) reduces HbA1c. In the current study, we examined the acute impacts of resistance exercise on glycemia during exercise and in the subsequent 24 h compared with aerobic exercise and no exercise. RESEARCH DESIGN AND METHODS Twelve physically active individuals with type 1 diabetes (HbA1c 7.1 ± 1.0%) performed 45 min of resistance exercise (three sets of seven exercises at eight repetitions maximum), 45 min of aerobic exercise (running at 60% of Vo2max), or no exercise on separate days. Plasma glucose was measured during and for 60 min after exercise. Interstitial glucose was measured by continuous glucose monitoring 24 h before, during, and 24 h after exercise. RESULTS Treatment-by-time interactions (P < 0.001) were found for changes in plasma glucose during and after exercise. Plasma glucose decreased from 8.4 ± 2.7 to 6.8 ± 2.3 mmol/L (P = 0.008) during resistance exercise and from 9.2 ± 3.4 to 5.8 ± 2.0 mmol/L (P = 0.001) during aerobic exercise. No significant changes were seen during the no-exercise control session. During recovery, glucose levels did not change significantly after resistance exercise but increased by 2.2 ± 0.6 mmol/L (P = 0.023) after aerobic exercise. Mean interstitial glucose from 4.5 to 6.0 h postexercise was significantly lower after resistance exercise versus aerobic exercise. CONCLUSIONS Resistance exercise causes less initial decline in blood glucose during the activity but is associated with more prolonged reductions in postexercise glycemia than aerobic exercise. This might account for HbA1c reductions found in studies of resistance exercise but not aerobic exercise in type 1 diabetes. PMID:23172972

Yardley, Jane E.; Kenny, Glen P.; Perkins, Bruce A.; Riddell, Michael C.; Balaa, Nadia; Malcolm, Janine; Boulay, Pierre; Khandwala, Farah; Sigal, Ronald J.

2013-01-01

198

HIV communication capacity strengthening: a critical review.  

PubMed

HIV communication is most effective and sustainable when it is designed and implemented locally and tailored to the local context. This requires capacity strengthening at national, subnational, and community levels. Through a review of the published and selected "grey" literature, we examine HIV communication capacity strengthening: definitions, measurements, implementation, and effects. We found limited documentation of HIV communication capacity needs or systematic approaches to address them. Most HIV communication capacity strengthening to date has focused on building individual competencies to design and manage social and behavior change communication programs through training courses, often coupled with networking opportunities for participants, post-training mentoring, and technical assistance. A few of these efforts have been evaluated through pre- and post-training tests and qualitative interviews with participants and have shown potential for improvement in individual skills and knowledge. Health communication capacity assessment tools that measure individual and organizational competencies exist, but they have most often been used to identify capacity building needs, not for evaluating capacity strengthening efforts. A new definition of capacity strengthening, grown out of recent efforts to improve effectiveness of international health and development programs, focuses on improving organizational and societal systems that support performance and individual competencies. We propose a holistic model for HIV communication capacity strengthening and call for rigorous documentation and evaluation to determine and scale-up optimal capacity building interventions for strengthening social and behavior change communication for HIV prevention, care, and treatment in developing countries. PMID:25007200

Lettenmaier, Cheryl; Kraft, Joan Marie; Raisanen, Keris; Serlemitsos, Elizabeth

2014-08-15

199

Comparison of Pathway and Center of Gravity of the Calcaneus on Non-Involved and Involved Sides According to Eccentric and Concentric Strengthening in Patients With Achilles Tendinopathy  

PubMed Central

This study compares the changes in pathway and center of gravity (COG) on the calcaneus of non-involved and involved sides according to eccentric and concentric strengthening in patients with unilateral Achilles tendinopathy. The goal was to define the biomechanical changes according to eccentric strengthening for the development of clinical guidelines. Eighteen patients with Achilles tendinopathy were recruited at the K Rehabilitation Hospital in Seoul. The subjects were instructed to perform 5 sessions of concentric strengthening. The calcaneal pathway was measured using a three-dimensional (3D) motion analyzer, and COG was measured by a force plate. Subsequently, eccentric strengthening was implemented, and identical variables were measured. Concentric and eccentric strengthening was carried out on both the involved and non-involved sides. There was no significant difference in the calcaneal pathway in patients with Achilles tendinopathy during concentric and eccentric strengthening. However, during eccentric strengthening, the calcaneal pathway significantly increased on the involved side compared to the non-involved side for all variables excluding the z-axis. COG significantly decreased on the involved side when compared to the non-involved side in patients with Achilles tendinopathy during eccentric and concentric strengthening. During concentric strengthening, all variables of the COG significantly increased on the involved side compared to the non-involved side. Compared with eccentric strengthening, concentric strengthening decreased the stability of ankle joints and increased the movement distance of the calcaneus in patients with Achilles tendinopathy. Furthermore, eccentric strengthening was verified to be an effective exercise method for prevention of Achilles tendinopathy through the reduction of forward and backward path length of foot pressure. The regular application of eccentric strengthening was found to be effective in the secondary prevention of Achilles tendinopathy in a clinical setting. Key point Compared with eccentric strengthening, concentric strengthening decreased the stability of ankle joints, increasing movement of the calcaneus in patients with Achilles tendinopathy. Eccentric strengthening was shown to be an effective exercise method for preventing Achilles tendinopathy through the reduction of forward and backward path length of foot pressure. It was verified that regular application of eccentric strengthening is effective in secondary prevention of Achilles tendinopathy in the clinical setting. PMID:24149129

Yu, JaeHo; Lee, GyuChang

2012-01-01

200

Combined Home Exercise Is More Effective Than Range-of-Motion Home Exercise in Patients with Ankylosing Spondylitis: A Randomized Controlled Trial  

PubMed Central

Home exercise is often recommended for management of patients with ankylosing spondylitis (AS); however, what kind of home exercise is more beneficial for patients with AS has not been determined yet. We aimed to compare the effectiveness of combined home exercise (COMB) and range-of-motion home exercise (ROM) in patients with AS. Nineteen subjects with AS completed either COMB (n = 9) or ROM (n = 10) program. The COMB program included range-of-motion, strengthening, and aerobic exercise while the ROM program consisted of daily range-of-motion exercise only. After exercise instruction, subjects in each group performed home exercise for 3 months. Assessment included cardiopulmonary exercise test, pulmonary function test, spinal mobility measurement, chest expansion, Bath Ankylosing Spondylitis Functional Index (BASFI), and other functional ability and laboratory tests. After exercise, the COMB group showed significant improvement in peak oxygen uptake (12.3%, P = 0.008) and BASFI (P = 0.028), and the changed score between pre- and postexercise data was significantly greater in the COMB group regarding peak oxygen uptake and BASFI. Significant improvement in finger-to-floor distance after 3-month exercise was found only in the COMB group (P = 0.033). This study demonstrates that a combined home exercise is more effective than range-of-motion home exercise alone in aerobic capacity and functional ability. PMID:25276785

Chuang, Chih-Cheng; Tseng, Ching-Shiang; Wei, James Cheng-Chung; Hsu, Wei-Chun; Lin, Yi-Jia

2014-01-01

201

Muscle mitochondrial density after exhaustive exercise in dogs - Prolonged restricted activity and retraining  

NASA Technical Reports Server (NTRS)

The effect of exhaustive treadmill exercise on mitochondrial density (MD) and ultrastructural changes in quadriceps femoris muscle was studied in 7 normal, healthy, male mongrel dogs before and after restricted activity (RA) and following a subsequent 2-month exercise retraining period. Mean time to exhaustion in the 2-month group decreased from 177 +/- 11 min before to 90 +/- 16 min after RA; retraining increased tolerance to 219 +/- 36 min above the pre-RA and 143 percent above the post-RA time. Post-RA exhaustion time in the 5-months group was 25 and 45 min. Muscle samples taken after RA showed abnormalities indicative of degeneration, which were reversed by retraining. Resting MD decreased from a control level of 27.8 percent to 14.7 percent and 16.3 percent, and was restored to 27.1 percent after retraining. Exhaustive exercise caused an increase in MD under control conditions and after RA, but not following retraining. Disruption of mitochondria after exercise was evident after 5-month confinement. Factors causing mitochondrial changes and eventually their disruption during exercise after restricted activity are not related as much to the state of fatigue as to the pre-exercise quality of the muscle modified by disease or training.

Nazar, K.; Greenleaf, J. E.; Philpott, D.; Pohoska, E.; Olszewska, K.; Kaciuba-Uscilko, H.

1993-01-01

202

Association of muscle strength, power, and optimal shortening velocity with functional abilities of women with chronic osteoarthritis participating in a multi-modal exercise program.  

PubMed

We assessed the relative association of quadriceps muscle strength and power as well as optimal shortening velocity (?(opt)) to physical functioning in 28 women aged 50-87 years with chronic osteoarthritis participating in a three-week multimodal exercise program. Quadriceps muscle strength, power, ?(opt), and functional performance using the Activities of Daily Living (ADL) scale, Timed Up & Go (TUG) test, Tinetti test, and 6-Minute Walking Test (6-MWT) were assessed pre- and postrehabilitation. With rehabilitation, patients improved the values of strength, power, and the results of all functional tests. Both at baseline and postrehabilitation, functional status was more strongly related to power and ?(opt) than to strength. Functional gains obtained with rehabilitation were not related to changes in power or ?(opt), and only very modestly related to changes in strength. Future studies should assess the benefits and feasibility of power- and velocity-oriented training in patients with osteoarthritis. PMID:24306542

Kostka, Joanna S; Czernicki, Jan W; Kostka, Tomasz J

2014-10-01

203

Exercise Is Medicine.  

ERIC Educational Resources Information Center

Suggests that exercise should be the first-line therapy for preventing and treating many common diseases; however, physicians need more training in how best to use exercise therapy. The paper explains the power of exercise and discusses how to motivate individuals to start safe, enjoyable, and life-saving exercise routines. (SM)

Elrick, Harold

1996-01-01

204

Optimisation of Shear Strengthened Reinforced Concrete Beams  

E-print Network

theory (SFT) (Loov, 1998) and the modified compression field theory (MCFT) (Vecchio and Collins, 1986) have been adapted to predict the capacity of CFRP strap strengthened beams (Hoult and Lees, 2009b; Lees et al., 2002; Yapa, 2011). Finite... these solutions. So optimisation can play a role in reducing the length of time for the evaluation process (hereafter referred to as ‘evaluation’). The MCFT and the SFT will be used as examples of evaluation methods for unstrengthened and CFRP strengthened beams...

Yapa, Hiran D.; Lees, Janet M.

2014-05-21

205

Biomechanical Evaluation of the Quadriceps Tendon Autograft for Anterior Cruciate Ligament Reconstruction  

PubMed Central

Background Recently, many surgeons have chosen the quadriceps tendon (QT) as an autograft for anterior cruciate ligament (ACL) reconstruction. However, there have not been biomechanical studies that quantitatively evaluated knee function after reconstruction using a QT autograft. Purpose To measure the 6 degrees of freedom knee kinematics and in situ graft forces after reconstruction with a QT autograft compared with a quadrupled semitendinosus and gracilis (QSTG) tendon autograft. Study Design Controlled laboratory study. Methods Ten human cadaveric knees (age, 54–64 years) were tested in 3 conditions: (1) intact, (2) ACL deficient, and (3) after ACL reconstruction using a QT or QSTG autograft. With use of a robotic/universal force-moment sensor testing system, knee kinematics and in situ forces in the ACL and autografts were obtained at 5 knee flexion angles under externally applied loads: (1) 134-N anterior tibial load, (2) 134-N anterior tibial load with 200-N axial compression, and (3) 10-N·m valgus and 5-N·m internal tibial torque. Results Under the anterior tibial load, both autografts restored anterior tibial translation to within 2.5 mm of the intact knee and in situ forces to within 20 N of the intact ACL at 15°, 30°, and 60°. Adding compression did not change these findings. With the combined rotatory load, the anterior tibial translation and graft in situ forces were again not significantly different from the intact ACL. There were no significant differences between the grafts under any experimental condition. Conclusion Reconstruction of the ACL with a QT autograft restored knee function to similar levels as that reconstructed with a QSTG autograft under loads simulating clinical examinations. Clinical Relevance The positive biomechanical results of this cadaveric study lend support to the use of a QT autograft for ACL reconstruction, as it could restore knee function immediately after surgery under applied loads that mimic clinical examinations. PMID:24401682

Sasaki, Norihiro; Farraro, Kathryn F.; Kim, Kwang E.; Woo, Savio L-Y.

2014-01-01

206

Sonography of the quadriceps muscle: Examination technique, normal anatomy, and traumatic lesions.  

PubMed

Lesions of the quadriceps muscle (QM) are frequently seen by sonographers, and in most cases they are the result of sports-related trauma. An accurate assessment of the severity of the lesion is essential, particularly when the patient is a professional athlete. In most cases, careful history-taking and a thorough physical examination are sufficient for making the diagnosis and indicating the most suitable imaging studies for each case. Clinical assessment alone, however, may not be sufficient for distinguishing contusions from small, partial tears or for estimating the size of a tear. Therefore, at least in patients who are professional athletes, imaging studies are necessary to plan appropriate therapy that will allow prompt functional recovery. Muscles cannot be visualized with conventional radiography, but it is used routinely in prepubertal patients because it can detect apophyseal detachments, which are the most frequent muscle lesion in this age group. Radiography is also useful when myositis ossificans is suspected. Magnetic resonance imaging, thanks to its excellent tissue contrast, allows simultaneous assessment of muscle, joint, and bone planes. It remains a second-line study due to its high cost and relatively low availability. It is also associated with various contraindications, the most important of which is the presence of a cardiac pacemaker. Ultrasonography has a number of advantages, including widespread availability, absence of contraindications, and low cost. It can also be used for dynamic studies of the muscle during contraction and relaxation, and if doubts arise, scans can easily be obtained of the contralateral muscle for comparison purposes. These qualities make it an excellent tool for follow-up of patients with QM lesions, when follow-up is necessary. This article reviews the anatomy of the QM, the technique used for standard ultrasound examination of this muscle, its normal appearance on ultrasound, and the sonographic characteristics of the most common traumatic lesions that affect it. PMID:23396806

Pasta, G; Nanni, G; Molini, L; Bianchi, S

2010-06-01

207

Sonography of the quadriceps muscle: Examination technique, normal anatomy, and traumatic lesions  

PubMed Central

Lesions of the quadriceps muscle (QM) are frequently seen by sonographers, and in most cases they are the result of sports-related trauma. An accurate assessment of the severity of the lesion is essential, particularly when the patient is a professional athlete. In most cases, careful history-taking and a thorough physical examination are sufficient for making the diagnosis and indicating the most suitable imaging studies for each case. Clinical assessment alone, however, may not be sufficient for distinguishing contusions from small, partial tears or for estimating the size of a tear. Therefore, at least in patients who are professional athletes, imaging studies are necessary to plan appropriate therapy that will allow prompt functional recovery. Muscles cannot be visualized with conventional radiography, but it is used routinely in prepubertal patients because it can detect apophyseal detachments, which are the most frequent muscle lesion in this age group. Radiography is also useful when myositis ossificans is suspected. Magnetic resonance imaging, thanks to its excellent tissue contrast, allows simultaneous assessment of muscle, joint, and bone planes. It remains a second-line study due to its high cost and relatively low availability. It is also associated with various contraindications, the most important of which is the presence of a cardiac pacemaker. Ultrasonography has a number of advantages, including widespread availability, absence of contraindications, and low cost. It can also be used for dynamic studies of the muscle during contraction and relaxation, and if doubts arise, scans can easily be obtained of the contralateral muscle for comparison purposes. These qualities make it an excellent tool for follow-up of patients with QM lesions, when follow-up is necessary. This article reviews the anatomy of the QM, the technique used for standard ultrasound examination of this muscle, its normal appearance on ultrasound, and the sonographic characteristics of the most common traumatic lesions that affect it. PMID:23396806

Pasta, G.; Nanni, G.; Molini, L.; Bianchi, S.

2010-01-01

208

Effect of resistance training on muscle use during exercise  

NASA Technical Reports Server (NTRS)

This study examined the effect of resistance training on exercise-induced contrast shift in magnetic resonance (MR) images. It was hypothesized that a given load could be lifted after training with less muscle showing contrast shift, thereby suggesting less muscle was used to perform the exercise. Nine males trained the left quadriceps femoris (QF) muscle 2 days/wk for 9 wk using 3-6 sets of 12 knee extensions each day. The right QF served as a control. Exercise-induced contrast shifts in MR images evoked by each of three bouts of exercise (5 sets of 10 knee extensions with a load equal to 50, 75, and 100% of the maximum pretraining load that could be lifted for 5 sets of 10 repetitions) were quantified pre- and posttraining. MR image contrast shift was quantified by determining QF cross-sectional area (CSA) showing increased spin-spin relaxation time. One repetition maximum increased 14% in the left trained QF and 7% in the right untrained QF. Left QF CSA increased 5%, with no change in right QSF CSA. Left QF CSA showing contrast shift was less after each bout of the exercise test posttraining. This was also true, to a lesser extent, for the right QF at the higher two loads. The results suggest that short-term resistance training reduces MR image contrast shift evoked by a given effort, thereby reflecting the use of less muscle to lift the load. Because this response was evident in both trained and contralateral untrained muscle, neural factors are suggested to be responsible. The consequence of this adaptation could be to increase 'stress' per unit area of active muscle during the course of training and thereby evoke hypertrophy.

Ploutz, Lori L.; Tesch, Per A.; Biro, Ronald L.; Dudley, Gary A.

1994-01-01

209

Resting and active motor thresholds versus stimulus–response curves to determine transcranial magnetic stimulation intensity in quadriceps femoris  

PubMed Central

Background Transcranial magnetic stimulation (TMS) is a widely-used investigative technique in motor cortical evaluation. Recently, there has been a surge in TMS studies evaluating lower-limb fatigue. TMS intensity of 120-130% resting motor threshold (RMT) and 120% active motor threshold (AMT) and TMS intensity determined using stimulus–response curves during muscular contraction have been used in these studies. With the expansion of fatigue research in locomotion, the quadriceps femoris is increasingly of interest. It is important to select a stimulus intensity appropriate to evaluate the variables, including voluntary activation, being measured in this functionally important muscle group. This study assessed whether selected quadriceps TMS stimulus intensity determined by frequently employed methods is similar between methods and muscles. Methods Stimulus intensity in vastus lateralis, rectus femoris and vastus medialis muscles was determined by RMT, AMT (i.e. during brief voluntary contractions at 10% maximal voluntary force, MVC) and maximal motor-evoked potential (MEP) amplitude from stimulus–response curves during brief voluntary contractions at 10, 20 and 50% MVC at different stimulus intensities. Results Stimulus intensity determined from a 10% MVC stimulus–response curve and at 120 and 130% RMT was higher than stimulus intensity at 120% AMT (lowest) and from a 50% MVC stimulus–response curve (p??0.05). Conclusions Similar optimal stimulus intensity and maximal MEP amplitudes at 20 and 50% MVC and the minimal risk of residual fatigue at 20% MVC suggest that a 20% MVC stimulus–response curve is appropriate for determining TMS stimulus intensity in the quadriceps femoris. The higher selected stimulus intensities at 120-130% RMT have the potential to cause increased coactivation and discomfort and the lower stimulus intensity at 120% AMT may underestimate evoked responses. One muscle may also act as a surrogate in determining optimal quadriceps femoris stimulation intensity. PMID:24655366

2014-01-01

210

Transcriptome Analysis in Venom Gland of the Predatory Giant Ant Dinoponera quadriceps: Insights into the Polypeptide Toxin Arsenal of Hymenopterans  

PubMed Central

Background Dinoponera quadriceps is a predatory giant ant that inhabits the Neotropical region and subdues its prey (insects) with stings that deliver a toxic cocktail of molecules. Human accidents occasionally occur and cause local pain and systemic symptoms. A comprehensive study of the D. quadriceps venom gland transcriptome is required to advance our knowledge about the toxin repertoire of the giant ant venom and to understand the physiopathological basis of Hymenoptera envenomation. Results We conducted a transcriptome analysis of a cDNA library from the D. quadriceps venom gland with Sanger sequencing in combination with whole-transcriptome shotgun deep sequencing. From the cDNA library, a total of 420 independent clones were analyzed. Although the proportion of dinoponeratoxin isoform precursors was high, the first giant ant venom inhibitor cysteine-knot (ICK) toxin was found. The deep next generation sequencing yielded a total of 2,514,767 raw reads that were assembled into 18,546 contigs. A BLAST search of the assembled contigs against non-redundant and Swiss-Prot databases showed that 6,463 contigs corresponded to BLASTx hits and indicated an interesting diversity of transcripts related to venom gene expression. The majority of these venom-related sequences code for a major polypeptide core, which comprises venom allergens, lethal-like proteins and esterases, and a minor peptide framework composed of inter-specific structurally conserved cysteine-rich toxins. Both the cDNA library and deep sequencing yielded large proportions of contigs that showed no similarities with known sequences. Conclusions To our knowledge, this is the first report of the venom gland transcriptome of the New World giant ant D. quadriceps. The glandular venom system was dissected, and the toxin arsenal was revealed; this process brought to light novel sequences that included an ICK-folded toxins, allergen proteins, esterases (phospholipases and carboxylesterases), and lethal-like toxins. These findings contribute to the understanding of the ecology, behavior and venomics of hymenopterans. PMID:24498135

Chong, Cheong-Meng; Leung, Siu Wai; Prieto-da-Silva, Álvaro R. B.; Havt, Alexandre; Quinet, Yves P.; Martins, Alice M. C.; Lee, Simon M. Y.; Rádis-Baptista, Gandhi

2014-01-01

211

Rapid hamstrings/quadriceps strength capacity in professional soccer players with different conventional isokinetic muscle strength ratios.  

PubMed

Muscle strength imbalance can be an important factor in hamstrings muscle strain. A hamstrings/quadriceps (H/Q) strength ratio based on concentric peak torque values (Hcon:Qcon) has traditionally been used to describe the potential for knee-joint destabilization. Because certain standard actions in soccer are explosive, the analysis of the H/Q strength ratio based on the rate of torque development (Hrtd:Qrtd) might also be useful in the evaluation of joint stability. The objective of this study was to compare the Hrtd:Qrtd between professional soccer players with heterogeneous values of Hcon:Qcon. Thirty-nine professional soccer players took part in the following procedures on different days: 1) Familiarization session with the isokinetic dynamometer, and 2) Two maximal isometric actions and five maximal concentric actions at 60°·s(-1) for hamstrings (H) and quadriceps (Q). Participants were ranked according to their Hcon:Qcon ratio. The median third was excluded to form a high torque group (HTG), and a low torque group (LTG). Peak isometric (H) and concentric (H and Q) torques and rate of torque development (H) were significantly greater in the HTG group. Similarly, Hcon:Qcon (0.68 ± 0.02 vs. 0.52 ± 0.03) and Hrtd:Qrtd (0.54 ± 0.12 vs. 0.43 ± 0.16) were significantly greater in the HTG group than in the LTG group. There was no significant correlation between Hcon:Qcon and Hrtd:Qrtd. It can be concluded that Hcon:Qcon and Hrtd:Qrtd are determined, but not fully defined, by shared putative physiological mechanisms. Thus, the physiologic and clinical significance of Hcon:Qcon and Hrtd:Qrtd to an athlete's individual evaluation might be different. Key pointsSoccer players with high (0.66-0.70) and low (0.50-0.54) conventional concentric hamstrings:quadriceps ratios (Hcon:Qcon) tend to demonstrate similar profiles (i.e., high and low, respectively) in their rate of the torque development H/Q ratio (Hrtd:Qrtd).The lack of a significant relationship between Hcon:Qcon and Hrtd:Qrtd suggests that these ratios are determined, but not fully defined, by shared putative physiological mechanisms.Preseason screening programs that monitor hamstrings:quadriceps ratios should recognize that the physiologic and clinical significance of Hcon:Qcon and Hrfd:Qrfd to an athlete's individual evaluation might be different. PMID:24149348

Greco, Camila C; Da Silva, Wendell L; Camarda, Sérgio R A; Denadai, Benedito S

2012-01-01

212

Rapid Hamstrings/Quadriceps Strength Capacity in Professional Soccer Players with Different Conventional Isokinetic Muscle Strength Ratios  

PubMed Central

Muscle strength imbalance can be an important factor in hamstrings muscle strain. A hamstrings/quadriceps (H/Q) strength ratio based on concentric peak torque values (Hcon:Qcon) has traditionally been used to describe the potential for knee-joint destabilization. Because certain standard actions in soccer are explosive, the analysis of the H/Q strength ratio based on the rate of torque development (Hrtd:Qrtd) might also be useful in the evaluation of joint stability. The objective of this study was to compare the Hrtd:Qrtd between professional soccer players with heterogeneous values of Hcon:Qcon. Thirty-nine professional soccer players took part in the following procedures on different days: 1) Familiarization session with the isokinetic dynamometer, and 2) Two maximal isometric actions and five maximal concentric actions at 60°·s-1 for hamstrings (H) and quadriceps (Q). Participants were ranked according to their Hcon:Qcon ratio. The median third was excluded to form a high torque group (HTG), and a low torque group (LTG). Peak isometric (H) and concentric (H and Q) torques and rate of torque development (H) were significantly greater in the HTG group. Similarly, Hcon:Qcon (0.68 ± 0.02 vs. 0.52 ± 0.03) and Hrtd:Qrtd (0.54 ± 0.12 vs. 0.43 ± 0.16) were significantly greater in the HTG group than in the LTG group. There was no significant correlation between Hcon:Qcon and Hrtd:Qrtd. It can be concluded that Hcon:Qcon and Hrtd:Qrtd are determined, but not fully defined, by shared putative physiological mechanisms. Thus, the physiologic and clinical significance of Hcon:Qcon and Hrtd:Qrtd to an athlete’s individual evaluation might be different. Key pointsSoccer players with high (0.66-0.70) and low (0.50-0.54) conventional concentric hamstrings:quadriceps ratios (Hcon:Qcon) tend to demonstrate similar profiles (i.e., high and low, respectively) in their rate of the torque development H/Q ratio (Hrtd:Qrtd).The lack of a significant relationship between Hcon:Qcon and Hrtd:Qrtd suggests that these ratios are determined, but not fully defined, by shared putative physiological mechanisms.Preseason screening programs that monitor hamstrings:quadriceps ratios should recognize that the physiologic and clinical significance of Hcon:Qcon and Hrfd:Qrfd to an athlete’s individual evaluation might be different. PMID:24149348

Greco, Camila C.; Da Silva, Wendell L.; Camarda, Sérgio R.A.; Denadai, Benedito S.

2012-01-01

213

Electromyographic Evaluation of Closed and Open Kinetic Chain Knee Rehabilitation Exercises  

PubMed Central

The use of closed kinetic chain knee rehabilitation exercises has been advocated in recent years. The primary reason cited for employing closed kinetic chain exercises is that these exercises result in less anteroposterior (A/P) shear force at the knee joint, when compared with traditionally used open kinetic chain exercises. The purpose of this study was to determine the electromyographical (EMG) activity ratio of quadriceps to hamstrings occurring in the following exercises: unilateral one quarter squats, leg extensions (N-K Table), lateral step-ups, and movements on the Fitter (Fitter International, Inc), Stair-master 4000 (Randal Sports/Medical Products, Inc), and slideboard. Ten female student-athletes participated in this study. EMG surface electrodes were applied over the rectus femoris and biceps femoris muscles. The subjects completed three maximum isometric contractions for both muscle groups to obtain baseline EMG data. They then performed repetitions of each exercise. These movements were videotaped simultaneously with a stationary shuttered video camera operating at 30 Hz. A computer program was used to analyze the videotaped performances for knee joint range of motion (ROM). Three trials of data were averaged. Baseline EMG activity was used to determine percentage of maximum EMG activity for each exercise. There were significant differences (p.<01) among the exercises for the following dependent variables: ROM, maximum angle, percent of maximum contraction, time of contraction, and total EMG (EMG area under the curve). This study suggests that the five closed kinetic chain exercises studied result in minimal A/P shear forces at the knee joint. ImagesINGINGINGING PMID:16558199

Graham, Victoria L.; Gehlsen, Gale M.; Edwards, Jennifer A.

1993-01-01

214

The Feasibility of performing resistance exercise with acutely ill hospitalized older adults  

PubMed Central

Background For older adults, hospitalization frequently results in deterioration of mobility and function. Nevertheless, there are little data about how older adults exercise in the hospital and definitive studies are not yet available to determine what type of physical activity will prevent hospital related decline. Strengthening exercise may prevent deconditioning and Pilates exercise, which focuses on proper body mechanics and posture, may promote safety. Methods A hospital-based resistance exercise program, which incorporates principles of resistance training and Pilates exercise, was developed and administered to intervention subjects to determine whether acutely-ill older patients can perform resistance exercise while in the hospital. Exercises were designed to be reproducible and easily performed in bed. The primary outcome measures were adherence and participation. Results Thirty-nine ill patients, recently admitted to an acute care hospital, who were over age 70 [mean age of 82.0 (SD= 7.3)] and ambulatory prior to admission, were randomized to the resistance exercise group (19) or passive range of motion (ROM) group (20). For the resistance exercise group, participation was 71% (p = 0.004) and adherence was 63% (p = 0.020). Participation and adherence for ROM exercises was 96% and 95%, respectively. Conclusion Using a standardized and simple exercise regimen, selected, ill, older adults in the hospital are able to comply with resistance exercise. Further studies are needed to determine if resistance exercise can prevent or treat hospital-related deterioration in mobility and function. PMID:14531932

Mallery, Laurie H; MacDonald, Elizabeth A; Hubley-Kozey, Cheryl L; Earl, Marie E; Rockwood, Kenneth; MacKnight, Chris

2003-01-01

215

Effects of muscular and aqua aerobic combined exercise on metabolic indices in elderly women with metabolic syndrome  

PubMed Central

The purpose of this study was to investigate the effects of muscle strengthening exercise using elastic thera-band and aquatic aerobic combined exercise on metabolic syndrome index in elderly with metabolic syndrome. Fifty-four were assigned to muscle strengthening exercise group (n = 19), aquatic aerobic exercise group (n = 19), and combined exercise group (n = 16). The muscle strength exercise, aquatic aerobic exercise and combined exercise were provided three times a week for 12 weeks. Metabolic syndrome indices[Fasting blood glucose, triglyceride, high density lipoprotein cholesterol (HDL-C), systolic blood pressure, diastolic blood pressure and waist circumference] were measured before and after the program. One-way ANOVA, paired t-test and two-way repeated ANOVA were used with the SPSS program for data analysis. There was a significant difference in triglyceride (p < .001), HDL-C (p = .010) and waist circumference (p = .016). Triglyceride and waist circumference was significantly decreased in combined group than muscle strength exercise group and aquatic exercise group. HDL-C was significantly increased in combined group than muscle strength exercise group. The results indicate that combined exercise was more effective in the improvement of dyslipidemia and abdominal obesity.

Yoo, Yong-Kwon; Kim, Soo-Keun; Song, Min-Sun

2013-01-01

216

Effects of muscular and aqua aerobic combined exercise on metabolic indices in elderly women with metabolic syndrome.  

PubMed

The purpose of this study was to investigate the effects of muscle strengthening exercise using elastic thera-band and aquatic aerobic combined exercise on metabolic syndrome index in elderly with metabolic syndrome. Fifty-four were assigned to muscle strengthening exercise group (n = 19), aquatic aerobic exercise group (n = 19), and combined exercise group (n = 16). The muscle strength exercise, aquatic aerobic exercise and combined exercise were provided three times a week for 12 weeks. Metabolic syndrome indices[Fasting blood glucose, triglyceride, high density lipoprotein cholesterol (HDL-C), systolic blood pressure, diastolic blood pressure and waist circumference] were measured before and after the program. One-way ANOVA, paired t-test and two-way repeated ANOVA were used with the SPSS program for data analysis. There was a significant difference in triglyceride (p < .001), HDL-C (p = .010) and waist circumference (p = .016). Triglyceride and waist circumference was significantly decreased in combined group than muscle strength exercise group and aquatic exercise group. HDL-C was significantly increased in combined group than muscle strength exercise group. The results indicate that combined exercise was more effective in the improvement of dyslipidemia and abdominal obesity. PMID:25566424

Yoo, Yong-Kwon; Kim, Soo-Keun; Song, Min-Sun

2013-12-01

217

Pelvic floor muscle training exercises  

MedlinePLUS

Kegel exercises ... Pelvic floor muscle training exercises are recommended for: Women with urinary stress incontinence People who have fecal incontinence Pelvic floor muscle training exercises can help ...

218

PGC-1? Is Required for Exercise- and Exercise Training-Induced UCP1 Up-Regulation in Mouse White Adipose Tissue  

PubMed Central

Background The aim of the present study was to test the hypotheses that 1) a single exercise bout increases UCP1 mRNA in both inguinal (i)WAT and epididymal (e)WAT, 2) UCP1 expression and responsiveness to exercise are different in iWAT and eWAT, 3) PGC-1? determines the basal levels of UCP1 and PRDM16 in WAT and 4) exercise and exercise training regulate UCP1 and PRDM16 expression in WAT in a PGC-1?-dependent manner. Methods Whole body PGC-1? knockout (KO) and wildtype (WT) littermate mice performed a single treadmill exercise bout at 14 m/min and 10% slope for 1 hour. Mice were sacrificed and iWAT, eWAT and quadriceps muscle were removed immediately after, 2, 6 and 10 hours after running, and from sedentary mice that served as controls. In addition, PGC-1? KO mice and WT littermates were exercise trained for 5 weeks with sedentary mice as untrained controls. Thirty-six-37 hours after the last exercise bout iWAT was removed. Results UCP1 mRNA content increased 19-fold in iWAT and 7.5-fold in eWAT peaking at 6 h and 0? of recovery, respectively, in WT but with no changes in PGC-1? KO mice. UCP1 protein was undetectable in eWAT and very low in iWAT of untrained mice but increased with exercise training to 4.4 (AU) in iWAT from WT mice without significant effects in PGC-1? KO mice. Conclusion The present observations provide evidence that exercise training increases UCP1 protein in iWAT through PGC-1?, likely as a cumulative effect of transient increases in UCP1 expression after each exercise bout. Moreover, the results suggest that iWAT is more responsive than eWAT in exercise-induced regulation of UCP1. In addition, as PRDM16 mRNA content decreased in recovery from acute exercise, the present findings suggest that acute exercise elicits regulation of several brown adipose tissue genes in mouse WAT. PMID:23717545

Ringholm, Stine; Grunnet Knudsen, Jakob; Leick, Lotte; Lundgaard, Anders; Munk Nielsen, Maja; Pilegaard, Henriette

2013-01-01

219

Association of Serum Bicarbonate Levels With Gait Speed and Quadriceps Strength in Older Adults  

PubMed Central

BACKGROUND Metabolic acidosis is associated with skeletal muscle proteolysis, and alkali supplementation has demonstrated improvements in lean body mass and urinary nitrogen wasting in several studies. However, the association of acidosis with functional outcomes has not been examined on a population-based level. STUDY DESIGN Cross-sectional study. SETTING & PARTICIPANTS 2,675 nationally representative adults 50 years of age and older in the National Health and Nutrition Examination Survey 1999 – 2002. FACTOR Serum bicarbonate level. OUTCOMES Low gait speed (gait speed) and low peak torque (peak torque) were defined as being in the lowest sex-specific quartile of gait speed and peak torque, respectively. MEASUREMENTS Serum bicarbonate was measured in all participants. gait speed was determined from a 20-foot timed walk. peak torque was calculated using peak isokinetic knee extensor force. RESULTS Serum bicarbonate <23 mEq/L was present in 22.7% of the cohort. Compared to participants with bicarbonate ?23 mEq/L, those with bicarbonate <23 mEq/L had higher body-mass index and serum albumin, were more likely to have low socioeconomic status, a diagnosis of diabetes mellitus, or glomerular filtration rate <60 mL/min/1.73 m2, and were less likely to use diuretics. Serum bicarbonate <23 mEq/L, compared with ?23 mEq/L, was associated with low gait speed (OR, 1.43; 95% confidence interval (CI), 1.04 – 1.95) and low peak torque (OR, 1.36; 95% CI, 1.07 – 1.74) after multivariable adjustment. The association with low peak torque was modified by race/ethnicity among women but not men (ORs of 1.52 (95% CI 1.08 – 2.13) for men, 2.33 (95% CI 1.23 – 4.44) for non- white women, and 0.93 (95% CI 0.47 – 1.82) for white women). LIMITATIONS Cross-sectional study using a single measurement of bicarbonate. CONCLUSIONS Lower serum bicarbonate levels are associated with slower gait speed and reduced quadriceps strength in older adults. Further studies should examine the effect of alkali therapy on functional outcomes. PMID:21354683

Abramowitz, Matthew K.; Hostetter, Thomas H.; Melamed, Michal L.

2011-01-01

220

Physiological benefits of exercise in artificial gravity: A broadband countermeasure to space flight related deconditioning  

NASA Astrophysics Data System (ADS)

Current countermeasures to space flight related physiological deconditioning have not been sufficiently effective. We believe that a comprehensive countermeasure is the combination of intermittent centrifugation (artificial gravity) and exercise. We aim to test the long-term effectiveness of this combination in terms of fitness benefits. As a first-order determination of effectiveness, subjects participated in an eight-week exercise program. Three times per week, they exercised using a stair-stepper on a short-radius (2 m) centrifuge spinning at 30 RPM, maintaining a target heart rate that was systematically increased over the exercise period. During the sessions, foot forces and stepping cadence, heart rate, and perceived exertion were measured. Before and after the eight-week exercise program, measurements included: body fat percentage, bone mineral content, quadriceps extension strength, push-ups endurance, stepping cadence for a given heart rate, and maximum stepping endurance. We find that stair-stepping on a centrifuge is safe and comfortable. Preliminary fitness results indicate that stair-stepping on a centrifuge may be effective in improving aerobic fitness, body composition, and strength. These results indicate that such a combination may also be effective as a countermeasure to space flight deconditioning.

Edmonds, Jessica L.; Jarchow, Thomas; Young, Laurence R.

2008-07-01

221

Lower limb joint angular position and muscle activity during elliptical exercise in healthy young men.  

PubMed

The purpose of this study was to compare lower extremity joint angular position and muscle activity during elliptical exercise using different foot positions and also during exercise on a lateral elliptical trainer. Sixteen men exercised on a lateral elliptical and on a standard elliptical trainer using straight foot position, increased toe-out angle, and a wide step. Motion capture and electromyography systems were used to obtain 3D lower extremity joint kinematics and muscle activity, respectively. The lateral trainer produced greater sagittal and frontal plane knee range of motion (ROM), greater peak knee flexion and extension, and higher vastus medialis activation compared with other conditions (P < .05). Toe-out and wide step produced the greatest and smallest peak knee adduction angles, respectively (P < .05). The lateral trainer produced greater sagittal and frontal plane hip ROM and greater peak hip extension and flexion compared with all other conditions (P < .05). Toe-out angle produced the largest peak hip external rotation angle and lowest gluteus muscle activation (P < .05). Findings from this study indicate that standard elliptical exercise with wide step may place the knee joint in a desirable frontal plane angular position to reduce medial knee loads, and that lateral elliptical exercise could help improve quadriceps strength but could also lead to larger knee contact forces. PMID:25268277

Paquette, Max R; Zucker-Levin, Audrey; DeVita, Paul; Hoekstra, Joseph; Pearsall, David

2015-02-01

222

The combined effect of cycling cadence and crank resistance on hamstrings and quadriceps muscle activities during cycling.  

PubMed

The effect of cycling cadence and crank resistance on the activity of hamstrings and quadriceps muscles was investigated during cycling movements of able-bodied subjects on a stationary bike with slow and fast speed against different resistance conditions. The ratio of average EMG amplitudes obtained in the two speed conditions (fast/slow) was computed in each resistance condition. This ratio is higher for both muscles if cycling against higher resistance. This shows that in higher resistance condition muscle activities are not only increased but the change of muscle activities with respect to cadence change varied according to resistance condition. Average EMG amplitudes increased at a higher rate with respect to change of cadence when cycling was performed in higher resistance condition. Besides, when cycling faster, hamstrings activity increased generally at a higher rate than that of quadriceps. The correlation between cadence and EMG amplitudes were also investigated. Considering hamstrings, this correlation was low and decreased as resistance increased. The correlation between the time required to drive one cycle and EMG amplitude is negative but in absolute value it is larger than the correlation of cadence and EMG amplitude. PMID:25532958

Katona, P; Pilissy, T; Tihanyi, A; Laczkó, József

2014-12-01

223

Boron strengthening in FeAl  

SciTech Connect

The effect of boron on the strength of B2-structured FeAl is considered as a function of composition, grain size and temperature. Boron does not affect the concentrations of antisite atoms or vacancies present, with the former increasing and the latter decreasing with increasing deviation from the stoichiometric composition. When vacancies are absent, the strength increase per at. % B per unit lattice strain, {Delta}{sigma}/({Delta}c x {epsilon}) increases with increasing aluminum concentration, but when vacancies are present (>45 at. % Al), {Delta}{sigma}/({Delta}c x {epsilon}) decreases again. Boron increases grain size strengthening in FeAl. B strengthening is roughly independent of temperature up to the yield strength peak but above the point, when diffusion-assisted deformation occurs, boron strengthening increases dramatically.

Baker, I.; Li, X.; Xiao, H.; Klein, O.; Nelson, C. [Dartmouth Coll., Hanover, NH (United States). Thayer School of Engineering; Carleton, R.L.; George, E.P. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.

1998-11-01

224

Exercise for Seniors  

MedlinePLUS

Exercise and physical activity are good for just about everyone, including older adults. There are four main ... jogging, dancing, swimming, and biking are examples. Strength exercises make your muscles stronger. Lifting weights or using ...

225

Clinical Applications for Exercise.  

ERIC Educational Resources Information Center

Patients with chronic conditions such as coronary artery disease, hypertension, diabetes, and obesity might benefit from prescribed exercise. Although exercise does not reverse pathologic changes, it may play a role in disease management. (JD)

Goldstein, David

1989-01-01

226

Boolean Raster Well Exercise  

NSDL National Science Digital Library

Enrique Gomezdelcampo, Bowling Green State University Summary This is a paper and pencil exercise using boolean raster grids. The exercise gives students a better understanding of how the GIS software works. ...

Gomezdelcampo, Enrique

227

Exercise and HIV  

MedlinePLUS

... Doing weight training followed by 30 minutes of cardiovascular exercise may be the best way to improve ... and keep your blood lipids and sugar down. Cardiovascular exercise means increasing oxygenation and heart rate while ...

228

Easy Exercises for Teens  

MedlinePLUS

... third component of well-rounded exercise. Check out yoga as one way to stay flexible. You can ... Schedule? Dynamic Stretching (Video) Pilates T'ai Chi Yoga Sports and Exercise Safety Strength Training Stretching Why ...

229

Rotator Cuff Exercises  

MedlinePLUS

... up, stretch your arms and shoulders, and do pendulum exercises. To do pendulum exercises, bend from the waist, letting your arms ... your shoulder. (Hint: This is like the backhand swing in tennis.) Lower the arm slowly. Repeat the ...

230

Assessing Exercise Limitation Using Cardiopulmonary Exercise Testing  

PubMed Central

The cardiopulmonary exercise test (CPET) is an important physiological investigation that can aid clinicians in their evaluation of exercise intolerance and dyspnea. Maximal oxygen consumption (V?O2max) is the gold-standard measure of aerobic fitness and is determined by the variables that define oxygen delivery in the Fick equation (V?O2 = cardiac output × arterial-venous O2 content difference). In healthy subjects, of the variables involved in oxygen delivery, it is the limitations of the cardiovascular system that are most responsible for limiting exercise, as ventilation and gas exchange are sufficient to maintain arterial O2 content up to peak exercise. Patients with lung disease can develop a pulmonary limitation to exercise which can contribute to exercise intolerance and dyspnea. In these patients, ventilation may be insufficient for metabolic demand, as demonstrated by an inadequate breathing reserve, expiratory flow limitation, dynamic hyperinflation, and/or retention of arterial CO2. Lung disease patients can also develop gas exchange impairments with exercise as demonstrated by an increased alveolar-to-arterial O2 pressure difference. CPET testing data, when combined with other clinical/investigation studies, can provide the clinician with an objective method to evaluate cardiopulmonary physiology and determination of exercise intolerance. PMID:23213518

Stickland, Michael K.; Butcher, Scott J.; Marciniuk, Darcy D.; Bhutani, Mohit

2012-01-01

231

Local bone mineral density, muscle strength, and exercise in adolescent boys: a comparative study of two groups with different muscle strength and exercise levels.  

PubMed

The primary objective of the present study was to evaluate the impact of physical activity and muscle strength on bone mineral density (BMD) of the tuberositas tibiae in adolescent boys. Two groups with different exercise levels were compared. The high activity group consisted of 20 subjects (age 15.9 +/- 0.3) from a junior ice hockey team. The reference group consisted of 24 volunteers (age 15.9 +/- 0.3) not training for more than 3 hours per week. The groups were matched for age, weight, and pubertal stage. BMDs (g/cm2) of the tuberositas tibiae and proximal tibia were measured using dual energy X-ray absorptiometry. Quadriceps strength was significantly higher in the high activity group (P < 0.01). Univariate correlations were measured between tuberositas tibiae BMD and pubertal stage, weight, height, BMI, fat mass, lean body mass, quadriceps strength, and hamstrings strength in the high activity group and the reference group, respectively. Quadriceps strength was estimated to be the best significant predictor of BMD of the tuberositas tibiae in the reference group. A multivariate analysis confirmed this result. In the high activity group, there was no significant predictor of BMD of the tuberositas tibiae. There was no significant difference in BMD at this site when comparing the two groups. However, five of the boys in the high activity group had a former history of Mb Osgood-Schlatter with a significantly lower BMD of the tuberositas tibiae than the rest of the boys in that group. After exclusion of these boys, the remaining 15 boys were matched against 20 boys from the reference group using the previous criteria. These 15 boys then showed a significantly higher BMD of the tuberositas tibiae (P < 0.05) but not of the proximal tibia than the 20 boys in the reference group. In conclusion, this study demonstrates site-specific increments of tuberositas tibiae BMD in adolescent ice hockey players unless they are affected by the negative effects on BMD by Mb Osgood-Schlatter. These increments seem primarily to be associated with forceful muscle contractions related to high quadriceps strength and not greater weight-bearing loading. Muscle strength seems to positively affect BMD of the tuberositas tibiae in adolescents, but only up to a certain level, above which additional muscle strength has no effect. PMID:8661480

Nordström, P; Nordström, G; Thorsen, K; Lorentzon, R

1996-06-01

232

Sport, Exercise & Health Strategy  

E-print Network

Sport, Exercise & Health Strategy The University's Vision is of an inclusive and collaborative advice and support to students. Sport, Exercise & Health Strategy 2010 ­ 2016 We aspire to provide standards, respect for the individual and a strong sense of collegiality. #12;Sport, Exercise & Health

Bristol, University of

233

Sport & Exercise Application Membership  

E-print Network

Sport & Exercise Application Membership www.hw.ac.uk/sports Sport & Exercise Opportunities Exercise for those that love a muscle burning workout to Zumba for the party lovers and yoga for those that like at the timetable at www.hw.ac.uk/sports A reduced programme is offered during summer holidays. Gym Programmes

Howie, Jim

234

Advanced resistive exercise device  

NASA Technical Reports Server (NTRS)

The present invention relates to an exercise device, which includes a vacuum cylinder and a flywheel. The flywheel provides an inertial component to the load, which is particularly well suited for use in space as it simulates exercising under normal gravity conditions. Also, the present invention relates to an exercise device, which has a vacuum cylinder and a load adjusting armbase assembly.

Raboin, Jasen L. (Inventor); Niebuhr, Jason (Inventor); Cruz, Santana F. (Inventor); Lamoreaux, Christopher D. (Inventor)

2008-01-01

235

Stretch Band Exercise Program  

ERIC Educational Resources Information Center

This article discusses how to use stretch bands for improving total body fitness and quality of life. A stretch band exercise program offers a versatile and inexpensive option to motivate participants to exercise. The authors suggest practical exercises that can be used in physical education to improve or maintain muscular strength and endurance,…

Skirka, Nicholas; Hume, Donald

2007-01-01

236

Exercise, Aging and Longevity.  

ERIC Educational Resources Information Center

The question of whether or not a lifelong program of exercise actually has a bearing on longevity is discussed. The effects of exercise on the aging process, and the longevity-exercise relationship are reviewed. The conflicting evidence on the subject is presented. (JL)

Brown, Stanley P.; Cundiff, David E.

1988-01-01

237

Prenatal exercise research.  

PubMed

In this review of recent research on prenatal exercise, studies from several different countries suggest that only approximately 40% of pregnant women exercise, even though about 92% are encouraged by their physicians to exercise, albeit with some 69% of the women being advised to limit their exercise. A moderate exercise regime reputedly increases infant birthweight to within the normal range, but only if exercise is decreased in late pregnancy. Lower intensity exercise such as water aerobics has decreased low back pain more than land-based physical exercise. Heart rate and blood pressure have been lower following yoga than walking, and complications like pregnancy-induced hypertension with associated intrauterine growth retardation and prematurity have been less frequent following yoga. No studies could be found on tai chi with pregnant women even though balance and the risk of falling are great concerns during pregnancy, and tai chi is one of the most effective forms of exercise for balance. Potential underlying mechanisms for exercise effects are that stimulating pressure receptors during exercise increases vagal activity which, in turn, decreases cortisol, increases serotonin and decreases substance P, leading to decreased pain. Decreased cortisol is particularly important inasmuch as cortisol negatively affects immune function and is a significant predictor of prematurity. Larger, more controlled trials are needed before recommendations can be made about the type and amount of pregnancy exercise. PMID:22721740

Field, Tiffany

2012-06-01

238

Enhancing Facial Aesthetics with Muscle Retraining Exercises-A Review  

PubMed Central

Facial attractiveness plays a key role in social interaction. ‘Smile’ is not only a single category of facial behaviour, but also the emotion of frank joy which is expressed on the face by the combined contraction of the muscles involved. When a patient visits the dental clinic for aesthetic reasons, the dentist considers not only the chief complaint but also the overall harmony of the face. This article describes muscle retraining exercises to achieve control over facial movements and improve facial appearance which may be considered following any type of dental rehabilitation. Muscle conditioning, training and strengthening through daily exercises will help to counter balance the aging effects. PMID:25302289

D’souza, Raina; Kini, Ashwini; D’souza, Henston; Shetty, Omkar

2014-01-01

239

Treatment and Prevention of Osteoarthritis through Exercise and Sports  

PubMed Central

Osteoarthritis (OA) is a degenerative joint disease with a high prevalence among older people. To date, the pathogenesis of the disease and the link between muscle function and OA is not entirely understood. As there is no known cure for OA, current research focuses on prevention and symptomatic treatment of the disorder. Recent research has indicated that muscle weakness precedes the onset of OA symptoms. Furthermore, several studies show a beneficial effect of land-based aerobic and strengthening exercises on pain relief and joint function. Therefore, current research focuses on the possibility to employ exercise and sports in the prevention and treatment of OA. PMID:21188091

Valderrabano, Victor; Steiger, Christina

2011-01-01

240

Strengthening 4-H Program Communication through Technology  

ERIC Educational Resources Information Center

Advances in technology are transforming how youth and parents interact with programs. The Strengthening 4-H Communication through Technology project was implemented in eight county 4-H programs in Northwest Minnesota. This article outlines the intentional process used to effectively implement technology in program planning. The project includes:…

Robideau, Kari; Santl, Karyn

2011-01-01

241

Didactic/Experiential Program for Memory Strengthening.  

ERIC Educational Resources Information Center

This paper describes a program for memory strengthening for older adults which combines lectures by experts with small group discussions. The importance of peer counselor involvement, particularly in focusing on the concerns of older people and the most effective ways to address these concerns is emphasized. Program objectives, session topics, and…

Chenoweth, Barbara; And Others

242

YogaTechniques to Lengthen, Strengthen &  

E-print Network

YogaTechniques to Lengthen, Strengthen & De-stress atWork: This session will teach partic- ipants of all fitness levels how to integrate yoga into their daily work schedules. Partic- ipants will learn the benefits of yoga and practice these asanas (yoga positions). If you spend multiple hours at a desk

Scott, Robert A.

243

Strengthening the K12 Teacher Workforce  

NSDL National Science Digital Library

Recent national reports, calling attention to the need to increase and enrich the nation's science and engineering talent pool, are placing an increased emphasis on expanding and strengthening the teacher workforce. This article offers information about and links to NSF initiatives in STEM teacher improvement and recruitment.

Prival, Joan

2007-10-24

244

Working Together for Children: Strengthening Transition Pathways  

ERIC Educational Resources Information Center

The "Working Together for Children: Strengthening Transition Pathways" Team has identified that there is a gap between the Early Childhood settings and schools within the Dubbo area. Through meetings with early childhood professionals within Dubbo the authors have identified that the current landscape of care and education within their community…

Collie, Louise; Willis, Felicity; Paine, Crystal; Windsor, Corina

2007-01-01

245

Exercise for Better Health  

NSDL National Science Digital Library

In this activity you will learn about components of a basic exercise program. You will also find some tips for making exercise a regular part of your life. Finally you will create a simple exercise program that includes the FIT formula. Doggonit!! You really wanted to just sit on the couch, watch another TV program, and eat a bag of chips. Your conscience, on the other hand, is telling you that you really need to get some exercise. What will you do? Hopefully, you are thinking seriously about some exercise. There are ...

2005-12-01

246

Mechanisms of quadriceps muscle weakness in knee joint osteoarthritis: the effects of prolonged vibration on torque and muscle activation in osteoarthritic and healthy control subjects  

PubMed Central

Introduction A consequence of knee joint osteoarthritis (OA) is an inability to fully activate the quadriceps muscles, a problem termed arthrogenic muscle inhibition (AMI). AMI leads to marked quadriceps weakness that impairs physical function and may hasten disease progression. The purpose of the present study was to determine whether ?-loop dysfunction contributes to AMI in people with knee joint OA. Methods Fifteen subjects with knee joint OA and 15 controls with no history of knee joint pathology participated in this study. Quadriceps and hamstrings peak isometric torque (Nm) and electromyography (EMG) amplitude were collected before and after 20 minutes of 50 Hz vibration applied to the infrapatellar tendon. Between-group differences in pre-vibration torque were analysed using a one-way analysis of covariance, with age, gender and body mass (kg) as the covariates. If the ?-loop is intact, vibration should decrease torque and EMG levels in the target muscle; if dysfunctional, then torque and EMG levels should not change following vibration. One-sample t tests were thus undertaken to analyse whether percentage changes in torque and EMG differed from zero after vibration in each group. In addition, analyses of covariance were utilised to analyse between-group differences in the percentage changes in torque and EMG following vibration. Results Pre-vibration quadriceps torque was significantly lower in the OA group compared with the control group (P = 0.005). Following tendon vibration, quadriceps torque (P < 0.001) and EMG amplitude (P ?0.001) decreased significantly in the control group but did not change in the OA group (all P > 0.299). Hamstrings torque and EMG amplitude were unchanged in both groups (all P > 0.204). The vibration-induced changes in quadriceps torque and EMG were significantly different between the OA and control groups (all P < 0.011). No between-group differences were observed for the change in hamstrings torque or EMG (all P > 0.554). Conclusions ?-loop dysfunction may contribute to AMI in individuals with knee joint OA, partially explaining the marked quadriceps weakness and atrophy that is often observed in this population. PMID:21933392

2011-01-01

247

Comparison of Active and Electrostimulated Recovery Strategies After Fatiguing Exercise  

PubMed Central

The purpose of this study was to compare an electrostimulated to an active recovery strategy after a submaximal isometric fatiguing exercise. Nineteen healthy men completed three sessions (separated by at least 4 weeks) which included a knee extensors provocation exercise consisting of 3 sets of 25 isometric contractions. Contraction intensity level was fixed respectively at 60%, 55% and 50% of previously determined maximal voluntary contraction for the first, second and third sets. This provocation exercise was followed by either an active (AR) recovery (25 min pedaling on a cycle ergometer), an electrostimulated (ESR) recovery (25-min continuous and non-tetanic (5 Hz) stimulation of the quadriceps) or a strictly passive recovery (PR). Peak torques of knee extensors and subjective perception of muscle pain (VAS, 0-10) were evaluated before (pre-ex), immediately after the provocation exercise (post-ex), after the recovery period (post-rec), as well as 75 minutes (1h15) and one day (24h) after the exercise bout. Time course of peak torque was similar among the different recovery modes: ~ 75% of initial values at post-ex, ~ 90% at post-rec and at 1h15. At 24h, peak torque reached a level close to baseline values (PR: 99.1 ± 10.7%, AR: 105.3 ± 12.2%, ESR: 104.4 ± 10.5%). VAS muscle pain scores decreased rapidly between post-ex and post-rec (p < 0.001); there were no significant differences between the three recovery modes (p = 0.64). In conclusion, following a submaximal isometric knee extension exercise, neither electrostimulated nor active recovery strategies significantly improved the time course of muscle function recovery. Key points Three sets of submaximal isometric contractions at 60%, 55% and 50% of MVC induced an early fatigue without DOMS but did not lead to exhaustion. In comparison with passive recovery, active and electrostimulated recovery did not lead to significantly higher MVC torques 24h after the exercise bout. No significant differences were demonstrated between the effects of passive, active and electrostimulated recoveries on muscle pain after repeated submaximal isometric contractions. PMID:24149681

Vanderthommen, Marc; Makrof, Souleyma; Demoulin, Christophe

2010-01-01

248

Sex differences in muscle fatigability and activation patterns of the human quadriceps femoris.  

PubMed

The purposes of this study were to determine if the fatigability of the quadriceps femoris varies by biological sex under conditions of normal muscle blood flow and ischemia, and if differences in neuromuscular activation patterns exist. Young men and women (n = 11/group; age 20-39 years) performed a sustained knee extension contraction at 25% of maximal force under conditions of occluded (OCC) and normal muscle blood flow (NON-OCC). Electromyographic (EMG) activity was recorded from the vastus lateralis (VL), rectus femoris (RF), vastus medialis (VM) and biceps femoris (BF) muscles, and analyzed for fatigue-induced changes in the amplitude and burst rate and duration (transient changes in motor unit recruitment) of the signal. Additionally, force fluctuations during the sustained contraction were quantified. Women had a longer time to task failure during the NON-OCC task [214.9 +/- 20.5 vs. 169.1 +/- 20.5 (SE) s] (P = 0.02), but not during the OCC task (179.6 + 19.6 vs. 165.2 +/- 19.6 s). EMG data demonstrated sex differences in the neuromuscular activation pattern of the RF muscle and the collectively averaged QF muscles. During the NON-OCC and OCC tasks women achieved a higher relative activation of the RF at task failure than men (NON-OCC: 40.68 +/- 4.57 vs. 24.49 +/- 4.19%; OCC: 36.80 +/- 5.45 vs. 24.41 +/- 2.12%) (P = 0.02 and 0.05, respectively). Also, during both tasks, they demonstrated a greater relative activation at task failure than men when an average of the VL, VM and RF was considered. Additionally, women exhibited a greater coefficient of variation in force fluctuations during the last-third of the fatiguing NON-OCC task (6.21 +/- 0.567 vs. 4.56 +/- 0.56%) (P = 0.001). No sex differences in EMG burst rate or duration were observed, although there was a trend towards greater EMG burst rate of the RF in association with muscle fatigue in the women (P = 0.09). Interestingly, the only neuromuscular activation variable that displayed a significant relationship with the time to task failure was the average relative EMG of the QF at task failure, and this relationship was observed under both experimental blood flow conditions (NON-OCC: r = 0.47, P = 0.03; OCC: r = 0.44, P = 0.04). These results indicate that sex differences in muscle blood flow and/or muscle metabolism are in part responsible for the female advantage in fatigue-resistance. Additionally, these findings suggest that men synergistically recruit the RF compartment to a lesser extent than women in association with muscle fatigue, and that women achieve an overall greater relative activation of the QF at task failure than men. However, the implications of these sex differences in neuromuscular activation patterns during fatiguing muscular contractions on the ability to withstand muscle fatigue (prolonged time to task failure) does not appear to be causally related. PMID:15791418

Clark, Brian C; Collier, Scott R; Manini, Todd M; Ploutz-Snyder, Lori L

2005-05-01

249

[Physical activity and public health: recommendations for exercise prescription].  

PubMed

During the last half century scientific data have been accumulated, through epidemiological and clinical studies that clearly document the significant health benefits associated with regular physical activity. This paper will analyse the latest recommendations for prescribing exercise in all age groups in healthy subjects and to individuals with chronic non-communicable diseases such as overweight, obesity, diabetes, hypertension, atherosclerotic cardiovascular disease and cancer, that contribute to the leading causes of global mortality. A search in the Pubmed database was performed and were also searched the recommendations of the World Health Organization and scientific organizations in Portugal. Most health benefits occur with at least 150 minutes of aerobic exercise of moderate intensity, accumulated over the week, which can be split into periods of at least 10 minutes. Brisk walking seems to be the preferred aerobic exercise. Vigorous intensity aerobic exercise and resistance exercises for muscle strengthening, at least two days a week are also recommended. Children, youth, older adults and people with overweight have particular needs for physical activity. Additional benefits occur with increasing quantity and quality of physical activity through the proper manipulation of the exercise density (intensity, frequency and duration). However, some physical activity is better than none. The role of health professionals in prescribing appropriate exercise to their patients is fundamental to their involvement in increasing their physical activity levels and thus contributing to their health promotion and prevention and treatment of major non-communicable chronic diseases. PMID:22713198

Mendes, Romeu; Sousa, Nelson; Barata, J L Themudo

2011-01-01

250

Different metabolic responses during incremental exercise assessed by localized 31P MRS in sprint and endurance athletes and untrained individuals.  

PubMed

Until recently, assessment of muscle metabolism was only possible by invasive sampling. 31P magnetic resonance spectroscopy (31P MRS) offers a way to study muscle metabolism non-invasively. The aim of the present study was to use spatially-resolved 31P MRS to assess the metabolism of the quadriceps muscle in sprint-trained, endurance-trained and untrained individuals during exercise and recovery. 5 sprint-trained (STA), 5 endurance-trained (ETA) and 7 untrained individuals (UTI) completed one unlocalized 31P MRS session to measure phosphocreatine (PCr) recovery, and a second session in which spatially-resolved 31P MR spectra were obtained. PCr recovery time constant (?) was significantly longer in STA (50±17 s) and UTI (41±9 s) than in ETA (30±4 s), (P<0.05). PCr changes during exercise differed between the groups, but were uniform across the different components of the quadriceps within each group. pH during recovery was higher for the ETA than for the UTI (P<0.05) and also higher than for the STA (P<0.01). Muscle volume was greater in STA than in UTI (P<0.05) but not different from ETA. Dynamic 31P MRS revealed considerable differences among endurance and sprint athletes and untrained people. This non-invasive method offers a way to quantify differences between individual muscles and muscle components in athletes compared to untrained individuals. PMID:23378173

Pesta, D; Paschke, V; Hoppel, F; Kobel, C; Kremser, C; Esterhammer, R; Burtscher, M; Kemp, G J; Schocke, M

2013-08-01

251

Knee joint biomechanics in closed-kinetic-chain exercises  

Microsoft Academic Search

Effective management of knee joint disorders demands appropriate rehabilitation programs to restore function while strengthening muscles. Excessive stresses in cartilage\\/menisci and forces in ligaments should be avoided to not exacerbate joint condition after an injury or reconstruction. Using a validated 3D nonlinear finite element model, detailed biomechanics of the entire joint in closed-kinetic-chain squat exercises are investigated at different flexion

M. Adouni; A. Shirazi-Adl

2009-01-01

252

Effects of 12-week combined exercise therapy on oxidative stress in female fibromyalgia patients.  

PubMed

The aims of this study were to investigate the effect of exercise therapy on the oxidative stress in fibromyalgia patients and relationship between oxidative stress and fibromyalgia symptoms. Thirty women diagnosed with fibromyalgia according to the American College of Rheumatology preliminary criteria, and 23 healthy women whose age- and weight-matched women were enrolled the study. Pain intensity with visual analog scale (VAS), the number of tender points, the fibromyalgia impact questionnaire (FIQ), the Beck depression inventory (BDI) were evaluated. The oxidative stress parameters thiobarbituric acid reactive substances, protein carbonyls, and nitric oxide, and antioxidant parameters thiols and catalase were investigated in patients and control group. After, combined aerobic and strengthen exercise regimen was given to fibromyalgia group. Exercise therapy consisted of a warming period of 10 min, aerobic exercises period of 20 min, muscle strengthening exercises for 20 min, and 10 min cooling down period. Therapy was lasting 1 h three times per week over a 12-week period. All parameters were reevaluated after the treatment in the patient group. The oxidative stress parameters levels were significantly higher, and antioxidant parameters were significantly lower in patients with fibromyalgia than in the controls. VAS, FIQ, and BDI scores decreased significantly with exercise therapy. The exercise improved all parameters of oxidative stress and antioxidant parameters. Also, all clinical parameters were improved with exercise. We should focus on oxidative stress in the treatment for fibromyalgia with the main objective of reducing oxidative load. PMID:24610539

Sar?fak?o?lu, Banu; Güzelant, Aliye Y?ld?r?m; Güzel, Eda Celik; Güzel, Sava?; K?z?ler, Ali R?za

2014-10-01

253

Skeletal muscle adiposity is associated with physical activity, exercise capacity and fibre shift in COPD  

PubMed Central

Quadriceps muscle phenotype varies widely between patients with chronic obstructive pulmonary disease (COPD) and cannot be determined without muscle biopsy. We hypothesised that measures of skeletal muscle adiposity could provide noninvasive biomarkers of muscle quality in this population. In 101 patients and 10 age-matched healthy controls, mid-thigh cross-sectional area, percentage intramuscular fat and skeletal muscle attenuation were calculated using computed tomography images and standard tissue attenuation ranges: fat -190– -30 HU; skeletal muscle -29–150 HU. Mean±sd percentage intramuscular fat was higher in the patient group (6.7±3.5% versus 4.3±1.2%, p = 0.03). Both percentage intramuscular fat and skeletal muscle attenuation were associated with physical activity level, exercise capacity and type I fibre proportion, independent of age, mid-thigh cross-sectional area and quadriceps strength. Combined with transfer factor of the lung for carbon monoxide, these variables could identify >80% of patients with fibre type shift with >65% specificity (area under the curve 0.83, 95% CI 0.72–0.95). Skeletal muscle adiposity assessed by computed tomography reflects multiple aspects of COPD related muscle dysfunction and may help to identify patients for trials of interventions targeted at specific muscle phenotypes. PMID:24993908

Maddocks, Matthew; Shrikrishna, Dinesh; Vitoriano, Simone; Natanek, Samantha A.; Tanner, Rebecca J.; Hart, Nicholas; Kemp, Paul R.; Moxham, John; Polkey, Michael I.; Hopkinson, Nicholas S.

2014-01-01

254

Skeletal muscle adiposity is associated with physical activity, exercise capacity and fibre shift in COPD.  

PubMed

Quadriceps muscle phenotype varies widely between patients with chronic obstructive pulmonary disease (COPD) and cannot be determined without muscle biopsy. We hypothesised that measures of skeletal muscle adiposity could provide noninvasive biomarkers of muscle quality in this population. In 101 patients and 10 age-matched healthy controls, mid-thigh cross-sectional area, percentage intramuscular fat and skeletal muscle attenuation were calculated using computed tomography images and standard tissue attenuation ranges: fat -190- -30 HU; skeletal muscle -29-150 HU. Mean±sd percentage intramuscular fat was higher in the patient group (6.7±3.5% versus 4.3±1.2%, p = 0.03). Both percentage intramuscular fat and skeletal muscle attenuation were associated with physical activity level, exercise capacity and type I fibre proportion, independent of age, mid-thigh cross-sectional area and quadriceps strength. Combined with transfer factor of the lung for carbon monoxide, these variables could identify >80% of patients with fibre type shift with >65% specificity (area under the curve 0.83, 95% CI 0.72-0.95). Skeletal muscle adiposity assessed by computed tomography reflects multiple aspects of COPD related muscle dysfunction and may help to identify patients for trials of interventions targeted at specific muscle phenotypes. PMID:24993908

Maddocks, Matthew; Shrikrishna, Dinesh; Vitoriano, Simone; Natanek, Samantha A; Tanner, Rebecca J; Hart, Nicholas; Kemp, Paul R; Moxham, John; Polkey, Michael I; Hopkinson, Nicholas S

2014-11-01

255

Simultaneous chronic rupture of quadriceps tendon and contra-lateral patellar tendon in a patient affected by tertiary hyperparatiroidism  

PubMed Central

Spontaneous ruptures of the extensor mechanism of the knee are very rare. They tend to increase considerably in patients with metabolic diseases such as chronic renal failure, hyperparathyroidism, diabetes, gout, and systemic lupus erythematosus. The reported case regards a 48-year-old man with chronic, spontaneous and simultaneous quadriceps, and contra-lateral patellar tendon rupture. The patient suffered from chronic renal failure and for the past year from tertiary hyperparathyroidism. Ruptured tendons were repaired and both knee were evaluated monthly for the next 12 months. Good functional recovery was achieved on both knees without relapse. This case emphasizes the importance of long-term high parathyroid hormone level in the etiology of tendons ruptures. PMID:19384613

Grecomoro, Giuseppe; Martorana, Umberto

2008-01-01

256

Extended Healing Validation of an Artificial Tendon to Connect the Quadriceps Muscle to the Tibia: 180-day Study  

PubMed Central

Whenever a tendon or its bone insertion is disrupted or removed, existing surgical techniques provide a temporary connection or scaffolding to promote healing, but the interface of living to nonliving materials soon breaks down under the stress of these applications, if it must bear the load more than acutely. Patients are thus disabled whose prostheses, defect size, or mere anatomy limit the availability or outcomes of such treatments. Our group developed the OrthoCoupler™ device to join skeletal muscle to prosthetic or natural structures without this interface breakdown. In this study, the goat knee extensor mechanism (quadriceps tendon, patella, and patellar tendon) was removed from the right hind limb in 16 goats. The device connected the quadriceps muscle to a stainless steel bone plate on the tibia. Mechanical testing and histology specimens were collected from each operated leg and contra lateral unoperated control legs at 180 days. Maximum forces in the operated leg (vs. unoperated) were 1400± 93N (vs. 1179± 61 N), linear stiffnesses were 33± 3 N/mm (vs. 37 ± 4N/mm), and elongations at failure were 92.1 ± 5.3 mm (vs. 68.4 ± 3.8 mm; mean ± SEM). Higher maximum forces (p = 0.02) and elongations at failure (p = 0.008) of legs with the device versus unoperated controls were significant; linear stiffnesses were not (p = 0.3). We believe this technology will yield improved procedures for clinical challenges in orthopaedic oncology, revision arthroplasty, tendon transfer, and tendon injury reconstruction. PMID:22179930

Melvin, Alan J.; Litsky, Alan S.; Mayerson, Joel L.; Stringer, Keith; Juncosa-Melvin, Natalia

2011-01-01

257

Downregulation of the serum response factor/miR-1 axis in the quadriceps of patients with COPD  

PubMed Central

Rationale Muscle atrophy confers a poor prognosis in patients with chronic obstructive pulmonary disease (COPD), yet the molecular pathways responsible are poorly characterised. Muscle-specific microRNAs and serum response factor (SRF) are important regulators of muscle phenotype that contribute to a feedback system to regulate muscle gene expression. The role of these factors in the skeletal muscle dysfunction that accompanies COPD is unknown. Methods 31 patients with COPD and 14 healthy age-matched controls underwent lung and quadriceps function assessments, measurement of daily activity and a percutaneous quadriceps muscle biopsy. The expression of muscle-specific microRNAs, myosin heavy chains and components of the serum response factor signalling pathway were determined by qPCR. Results A reduction in expression of miR-1 (2.5-fold, p=0.01) and the myocardin-related transcription factors (MRTFs) A and B was observed in patients compared with controls (MRTF-A mRNA: twofold, p=0.028; MRTF-B mRNA: fourfold, p=0.011). miR-1 expression was associated with smoking history, lung function, fat-free mass index, 6?min walk distance and percentage of type 1 fibres. miR-133 and miR-206 were negatively correlated with daily physical activity. Insulin-like growth factor 1 mRNA was increased in the patients and miR-1 was negatively correlated with phosphorylation of the kinase Akt. Furthermore, the protein levels of histone deacetylase 4, another miR-1 target, were increased in the patients. Conclusions Downregulation of the activity of the MRTF-SRF axis and the expression of muscle-specific microRNAs, particularly miR-1, may contribute to COPD-associated skeletal muscle dysfunction. PMID:21998125

Lewis, Amy; Riddoch-Contreras, Joanna; Natanek, Samantha A; Donaldson, Anna; Man, William D-C; Moxham, John; Hopkinson, Nicholas S; Polkey, Michael I

2011-01-01

258

Muscle Adaptations Following Short-Duration Bed Rest with Integrated Resistance, Interval, and Aerobic Exercise  

NASA Technical Reports Server (NTRS)

Unloading of the musculoskeletal system during space flight results in deconditioning that may impair mission-related task performance in astronauts. Exercise countermeasures have been frequently tested during bed rest (BR) and limb suspension; however, high-intensity, short-duration exercise prescriptions have not been fully explored. PURPOSE: To determine if a high intensity resistance, interval, and aerobic exercise program could protect against muscle atrophy and dysfunction when performed during short duration BR. METHODS: Nine subjects (1 female, 8 male) performed a combination of supine exercises during 2 weeks of horizontal BR. Resistance exercise (3 d / wk) consisted of squat, leg press, hamstring curl, and heel raise exercises (3 sets, 12 repetitions). Aerobic (6 d / wk) sessions alternated continuous (75% VO2 peak) and interval exercise (30 s, 2 min, and 4 min) and were completed on a supine cycle ergometer and vertical treadmill, respectively. Muscle volumes of the upper leg were calculated pre, mid, and post-BR using magnetic resonance imaging. Maximal isometric force (MIF), rate of force development (RFD), and peak power of the lower body extensors were measured twice before BR (averaged to represent pre) and once post BR. ANOVA with repeated measures and a priori planned contrasts were used to test for differences. RESULTS: There were no changes to quadriceps, hamstring, and adductor muscle volumes at mid and post BR time points compared to pre BR (Table 1). Peak power increased significantly from 1614 +/- 372 W to 1739 +/- 359 W post BR (+7.7%, p = 0.035). Neither MIF (pre: 1676 +/- 320 N vs. post: 1711 +/- 250 N, +2.1%, p = 0.333) nor RFD (pre: 7534 +/- 1265 N/ms vs. post: 6951 +/- 1241 N/ms, -7.7%, p = 0.136) were significantly impaired post BR.

Hackney, Kyle J.; Scott, Jessica M.; Buxton, Roxanne; Redd-Goetchius, Elizabeth; Crowell, J. Brent; Everett, Meghan E.; Wickwire, Jason; Ryder, Jeffrey W.; Bloomberg, Jacob J.; Ploutz-Snyder, Lori L.

2011-01-01

259

Low-volume resistance exercise attenuates the decline in strength and muscle mass associated with immobilization.  

PubMed

We determined the effectiveness of low-volume resistance exercise (EX) for the attenuation of loss of muscle mass and strength during leg immobilization. Men (N = 5) and women (N = 12, age 24 ± 5 years, body mass index 25.4 ± 3.6 kg/m(2)) were divided into two groups: exercise (EX; n = 12) and control (CON; n = 5). Subjects wore a knee brace on one leg that prevented weight bearing for 14 days. Resistance exercise (EX; 80% of maximal) was performed by the immobilized limb every other day. Immobilization induced a significant reduction (P < 0.05) in muscle fiber and thigh cross-sectional area (CSA), isometric knee extensor, and plantarflexor strength in the CON (P < 0.01) but not in the EX group. There were significant losses in triceps surae CSA in the CON and EX groups (P < 0.05), but the losses were greater in CON subjects (P < 0.01). A minimal volume (140 contractions in 14 days) of resistive exercise is an effective countermeasure against immobilization-induced atrophy of the quadriceps femoris but is only partially effective for the triceps surae. PMID:20658567

Oates, Bryan R; Glover, Elisa I; West, Daniel W; Fry, Jessica L; Tarnopolsky, Mark A; Phillips, Stuart M

2010-10-01

260

Strengthening Bridges with Prestressed CFRP Strips  

NASA Astrophysics Data System (ADS)

Limitation of bridge's carrying bearing capacity due to aging and deterioration is a common problem faced by road administration and drivers. Rehabilitation of bridges including strengthening may be applied in order to maintain or upgrade existing bridge parameters. The case studies of strengthening of two small bridges with high modulus prestressed CFRP strips have been presented in the paper. The first one - reinforced concrete slab bridge - and the other - composite steel-concrete girder bridge - have been successfully upgraded with quite new technology. In both cases the additional CFRP reinforcement let increasing of bridge carrying capacity from 15 till 40 metric tons. The CFRP strip prestressing system named Neoxe Prestressing System (NPS), developed by multi-disciplinary team and tested at full scale in Rzeszow University of Technology, has been also described in the paper.

Siwowski, Tomasz; ?ó?towski, Piotr

2012-06-01

261

Articulating Support for Horizontal Resistive Exercise  

NASA Technical Reports Server (NTRS)

A versatile mechanical device provides support for a user engaged in any of a variety of resistive exercises in a substantially horizontal orientation. The unique features and versatility of the device promise to be useful in bedrest studies, rehabilitation, and specialized strength training. The device affords a capability for selectively loading and unloading of portions of the user s body through its support mechanisms, so that specific parts of the body can be trained with little or no effect on other parts that may be disabled or in the process of recovery from injury. Thus, the device is ideal for rehabilitation exercise programs prescribed by physicians and physical therapists. The capability for selective loading and support also offers potential benefits to strength and conditioning trainers and athletes who wish to selectively strengthen selected parts. The principal innovative aspect of the device is that it supports the subject s weight while enabling the subject, lying substantially horizontally, to perform an exercise that closely approximates a full standing squat. The device includes mechanisms that support the subject in such a way that the hips are free to translate both horizontally and vertically and are free to rotate about the line connecting the hips. At the same time, the shoulders are free to translate horizontally while the upper back is free to rotate about the line connecting the shoulders. Among the mechanisms for hip motion and support is a counterbalance that offsets the weight of the subject as the subject s pelvis translates horizontally and vertically and rotates the pelvis about the line connecting the hips. The counterbalance is connected to a pelvic support system that allows these pelvic movements. The subject is also supported at the shoulder by a mechanism that can tilt to provide continuous support of the upper back while allowing the rotation required for arching the back as the pelvis is displaced. The shoulder support also affords a capability for horizontal motion, and acts as the point of attachment of a load that is provided for squat and heel-raise exercises. The device is compatible with any resistive-exercise machine that provides bilateral loading via a moving cable or other mechanical linkage. The hip-translation and shoulder-translation and -rotation degrees of freedom of the supports can be locked individually or in combination in order to support the subject as necessary for exercises other than the standing squat. If necessary, for such exercises, the load can be applied directly to the subject by use of various attachments. In addition to the aforementioned heel raise, such exercises include the upright row, leg press, curls, extension of the triceps, front raise, lateral raise, and rear raise.

Gundo, Daniel; Schaffner, Grant; Bentley, Jason; Loehr, James A.

2005-01-01

262

Bonded Fibre Reinforced Polymer Strengthening in a Real Fire   

E-print Network

FRP strengthening is critically dependent upon the bonding adhesive. The adhesive used is typically an ambient cure epoxy with a glass transition temperature as low as 60ºC. This paper describes the performance of bonded FRP strengthening within...

Stratford, Tim J; Gillie, Martin; Chen, J; Usmani, Asif

263

Doctoral Bursaries Available Global Health Research Capacity Strengthening Program (GHRCAPS)  

E-print Network

1 Doctoral Bursaries Available Global Health Research Capacity Strengthening Program (GHRCAPS) What is GHRCAPS? The Global Health Research Capacity Strengthening Program (GHRCAPS to the national and international development of global health research by recruiting and training

Barthelat, Francois

264

Postdoctoral Bursaries Available Global Health Research Capacity Strengthening Program (GHRCAPS)  

E-print Network

1 Postdoctoral Bursaries Available Global Health Research Capacity Strengthening Program (GHRCAPS) What is GHRCAPS? The Global Health Research Capacity Strengthening Program (GHRCAPS to the national and international development of global health research by recruiting and training

Barthelat, Francois

265

USING PERFORMANCE MEASUREMENTS TO EVALUATE AND STRENGTHEN INFORMATION SYSTEM SECURITY  

E-print Network

USING PERFORMANCE MEASUREMENTS TO EVALUATE AND STRENGTHEN INFORMATION SYSTEM SECURITY Shirley about the security of information systems for the decision makers of organizations. When organizations to strengthen the overall security of their information and their information systems. Organizations

266

Effectiveness of muscle strengthening and description of protocols for preventing falls in the elderly: a systematic review  

PubMed Central

Background Falls are a geriatric syndrome that is considered a significant public health problem in terms of morbidity and mortality because they lead to a decline in functional capacity and an impaired quality of life in the elderly. Lower limb muscle strengthening seems to be an effective intervention for preventing falls; however, there is no consensus regarding the best method for increasing lower limb muscle strength. Objectives To analyze the effectiveness of lower limb muscle strengthening and to investigate and describe the protocols used for preventing falls in elderly subjects. Method We performed a systematic review of randomized and controlled clinical trials published between 2002 and 2012 in the databases PubMed, EMBASE, Scopus, Web of Science, and PEDro that cited some type of lower limb muscle strengthening protocol and that evaluated the incidence of falls as the primary outcome exclusively in elderly subjects. Twelve studies met the inclusion criteria. Qualitative analysis was performed by independent reviewers applying the PEDro scale. Results The data obtained from the selected studies showed lower fall rates in the intervention groups compared to controls. Six studies described the lower limb muscle strengthening protocol in detail. High methodological quality was found in 6 studies (PEDro score ?7/10 points). Conclusions The methodological quality of the studies in this area appears to leave little doubt regarding the effectiveness of lower limb strengthening exercises for preventing falls in elderly subjects, however the interventions in these studies were poorly reported. PMID:24760166

Ishigaki, Erika Y.; Ramos, Lidiane G.; Carvalho, Elisa S.; Lunardi, Adriana C.

2014-01-01

267

Chin tuck against resistance (CTAR): new method for enhancing suprahyoid muscle activity using a Shaker-type exercise.  

PubMed

For patients with dysphagia resulting from upper esophageal sphincter dysfunction, strengthening the suprahyoid muscles through therapeutic exercise has proved effective in restoring oral feeding. The aim of this study was to compare the maximum and mean surface electromyography (sEMG) activity of the suprahyoid muscles during the Chin Tuck Against Resistance (CTAR) exercise and the Shaker exercise for both isokinetic and isometric tasks. During the CTAR exercises, the participant is seated while tucking the chin to compress an inflatable rubber ball, whereas during the Shaker exercise, the participant is lay supine while lifting the head to look at the feet. Forty healthy participants (20 males, 20 females) aged 21-39 years completed all four tasks in counterbalanced order, with measures of resting activation taken prior to each exercise. Although subjective feedback suggested that the sitting position for CTAR is less strenuous than the supine position for Shaker, the results of separate analyses showed significantly greater maximum sEMG values during the CTAR isokinetic and isometric exercises than during the equivalent Shaker exercises, and significantly greater mean sEMG values were observed for the CTAR isometric exercise than for the Shaker isometric exercise. Clinical trials are now needed, but the CTAR exercises appear effective in exercising the suprahyoid muscles, and they could achieve therapeutic effects comparable to those of Shaker exercises, with the potential for greater compliance by patients. PMID:24337867

Yoon, Wai Lam; Khoo, Jason Kai Peng; Rickard Liow, Susan J

2014-04-01

268

Exercise therapy for fibromyalgia.  

PubMed

Fibromyalgia syndrome, a chronic condition typically characterized by widespread pain, nonrestorative sleep, fatigue, cognitive dysfunction, and other somatic symptoms, negatively impacts physical and emotional function and reduces quality of life. Exercise is commonly recommended in the management of people with fibromyalgia, and interest in examining exercise benefits for those with the syndrome has grown substantially over the past 25 years. Research supports aerobic and strength training to improve physical fitness and function, reduce fibromyalgia symptoms, and improve quality of life. However, other forms of exercise (e.g., tai chi, yoga, Nordic walking, vibration techniques) and lifestyle physical activity also have been investigated to determine their effects. This paper highlights findings from recent randomized controlled trials and reviews of exercise for people with fibromyalgia, and includes information regarding factors that influence response and adherence to exercise to assist clinicians with exercise and physical activity prescription decision-making to optimize health and well-being. PMID:21725900

Busch, Angela J; Webber, Sandra C; Brachaniec, Mary; Bidonde, Julia; Bello-Haas, Vanina Dal; Danyliw, Adrienne D; Overend, Tom J; Richards, Rachel S; Sawant, Anuradha; Schachter, Candice L

2011-10-01

269

The Effect of an Inclined Ankle on the Activation of the Abductor Hallucis Muscle during Short Foot Exercise  

PubMed Central

[Purpose] The purpose of this study was to identify the effects of an inclined ankle on the activation of the abductor hallucis muscle during short foot exercises. [Subjects] We recruited 14 healthy volunteers who were free of pain, and did not suffer from arthritis or osteomuscular problems related to the foot or ankle. [Methods] The subjects performed short foot exercises and short inclined foot exercises with 30° passive ankle dorsiflexion. [Results] The exercise with an inclined foot showed a significantly larger activation of the abductor hallucis than that shown during the neutral short foot exercises. [Conclusion] These results suggest that passive ankle dorsiflexion during short foot exercise for strengthening the abductor hallucis is a more effective clinical treatment exercise. PMID:24764646

Heo, Hyo-Jin; An, Duk-Hyun

2014-01-01

270

Strengthening Self-Checksumming via Self-Modifying Code  

E-print Network

Strengthening Self-Checksumming via Self-Modifying Code Jonathon T. Giffin, Mihai Christodorescu,mihai,lpkruger}@cs.wisc.edu #12;6 December 2005 Strengthening Self-Checksumming via Self-Modifying Code 2 Problem 1 Detect malicious modifications to code #12;6 December 2005 Strengthening Self-Checksumming via Self-Modifying Code

Miller, Barton P.

271

Candidate Exercise Technologies and Prescriptions  

NASA Technical Reports Server (NTRS)

This slide presentation reviews potential exercise technologies to counter the effects of space flight. It includes a overview of the exercise countermeasures project, a review of some of the candidate exercise technologies being considered and a few of the analog exercise hardware devices, and a review of new studies that are designed to optimize the current and future exercise protocols.

Loerch, Linda H.

2010-01-01

272

Advanced Resistive Exercise Device  

NASA Technical Reports Server (NTRS)

The advanced resistive exercise device (ARED), now at the prototype stage of development, is a versatile machine that can be used to perform different customized exercises for which, heretofore, it has been necessary to use different machines. Conceived as a means of helping astronauts and others to maintain muscle and bone strength and endurance in low-gravity environments, the ARED could also prove advantageous in terrestrial settings (e.g., health clubs and military training facilities) in which many users are exercising simultaneously and there is heavy demand for use of exercise machines.

Raboin, Jasen; Niebuhr, Jason; Cruz, Santana; Lamoreaux, chris

2007-01-01

273

Exercise and Physical Fitness  

MedlinePLUS

... Control your weight Lower your risk of heart disease Lower your risk for type 2 diabetes and metabolic syndrome Lower your risk of some cancers Strengthen your bones and muscles Improve your mental health and mood ...

274

Resistive Exercise for Arthritic Cartilage Health (REACH): A randomized double-blind, sham-exercise controlled trial  

PubMed Central

Background This article provides the rationale and methodology, of the first randomised controlled trial to our knowledge designed to assess the efficacy of progressive resistance training on cartilage morphology in women with knee osteoarthritis. Development and progression of osteoarthritis is multifactorial, with obesity, quadriceps weakness, joint malalignment, and abnormal mechanical joint forces particularly relevant to this study. Progressive resistance training has been reported to improve pain and disability in osteoarthritic cohorts. However, the disease-modifying potential of progressive resistance training for the articular cartilage degeneration characteristic of osteoarthritis is unknown. Our aim was to investigate the effect of high intensity progressive resistance training on articular cartilage degeneration in women with knee osteoarthritis. Methods Our cohort consisted of women over 40 years of age with primary knee osteoarthritis, according to the American College of Rheumatology clinical criteria. Primary outcome was blinded measurement of cartilage morphology via magnetic resonance imaging scan of the tibiofemoral joint. Secondary outcomes included walking endurance, balance, muscle strength, endurance, power, and velocity, body composition, pain, disability, depressive symptoms, and quality of life. Participants were randomized into a supervised progressive resistance training or sham-exercise group. The progressive resistance training group trained muscles around the hip and knee at 80% of their peak strength and progressed 3% per session, 3 days per week for 6 months. The sham-exercise group completed all exercises except hip adduction, but without added resistance or progression. Outcomes were repeated at 3 and 6 months, except for the magnetic resonance imaging scan, which was only repeated at 6 months. Discussion Our results will provide an evaluation of the disease-modifying potential of progressive resistance training for osteoarthritis. Trial Registration ANZCTR Reference No. 12605000116628 PMID:19144148

Lange, Angela K; Vanwanseele, Benedicte; Foroughi, Nasim; Baker, Michael K; Shnier, Ronald; Smith, Richard M; Singh, Maria A Fiatarone

2009-01-01

275

Role of manual therapy with exercise regime versus exercise regime alone in the management of non-specific chronic neck pain.  

PubMed

To evaluate the role of manual therapy with exercise regime versus exercise regime alone in the management of non-specific chronic neck pain. In this 62 subjects randomized controlled trial 31 subjects in group A received manual therapy (manipulation) with supervised exercise regime whilst 31 subjects in group B performed only supervised exercise regime for the period of 3 weeks. Both groups had a home exercise program consisted of strengthening exercises for neck/scapuluar stability, stretching and general range of motion exercises for neck with advice regarding posture awareness and correction for 3 months. The results suggested significant reduction in pain intensity level in both groups; over 3 weeks and 12 weeks' time period in relation to baseline on visual analog scale (p=0.001). Similarly, statistically significant improvements noticed in Neck Disability Index (NDI) (p=0.0001) in both groups while looking at baseline data with reference to 12 weeks' time period. On closer inspection, the manual therapy (manipulation) with exercise regime appeared as a favorable treatment preference compared with exercise regime alone. PMID:25410083

Akhter, Saeed; Khan, Muhammad; Ali, Syed Shahzad; Soomro, Rabial Rani

2014-11-01

276

Effects of Exercise Rehab on Male Asthmatic Patients: Aerobic Verses Rebound Training  

PubMed Central

Background: There are some auspicious records on applying aerobic exercise for asthmatic patients. Recently, it is suggested that rebound exercise might even increase the gains. This study was designed to compare the effects of rebound therapy to aerobic training in male asthmatic patients. Methods: Sample included 37 male asthmatic patients (20-40 years) from the same respiratory clinic. After signing the informed consent, subjects volunteered to take part in control, rebound, or aerobic groups. There was no change in the routine medical treatment of patients. Supervised exercise programs continued for 8 weeks, consisting of two sessions of 45 to 60 minutes per week. Criteria measures were assessed pre- and post exercise program. Peak exercise capacity (VO2peak) was estimated by modified Bruce protocol, Forced vital capacity (FVC), Forced expiratory volume in 1 second (FEV1), and FEV1% were measured by spirometer. Data were analyzed by repeated measure analysis of variance (ANOVA). Results: Significant interactions were observed for all 4 criteria measures (P < 0.01), meaning that both the exercise programs were effective in improving FVC, FEV1, FEV1%, and VO2peak. Rebound exercise produced more improvement in FEV1, FEV1%, and VO2peak. Conclusions: Regular exercise strengthens the respiratory muscles and improves the cellular respiration. At the same time, it improves the muscular, respiratory, and cardio-vascular systems. Effects of rebound exercise seem to be promising. Findings suggest that rebound exercise is a useful complementary means for asthmatic male patients. PMID:23717762

Zolaktaf, Vahid; Ghasemi, Gholam A; Sadeghi, Morteza

2013-01-01

277

Peripheral and central fatigue after muscle-damaging exercise is muscle length dependent and inversely related.  

PubMed

Healthy untrained men performed 10 series of 12 knee eccentric extension repetitions (EE) at 160 degrees /s. The maximal voluntary isometric contraction force of the quadriceps muscle, the maximal rate of electrically induced torque development (RTD) and relaxation (RTR), isokinetic concentric torque at 30 degrees /s, the electrostimulation-induced torque at 20 and 100Hz frequencies were established before and after EE at shorter and longer muscle lengths. Besides, voluntary activation (VA) index and central activation ratio (CAR) were tested. There was more peripheral fatigue than central after EE. We established more central fatigue as well as low frequency fatigue at a shorter muscle length compared to the longer muscle length. Relative RTD as well as relative RTR, improved after EE and did not depend on the muscle length. Finally, central fatigue is inversely significantly related with the eccentric torque reduction during eccentric exercise and with the changes in muscle torque induced by low frequency stimulation. PMID:20347333

Skurvydas, Albertas; Brazaitis, Marius; Kamandulis, Sigitas; Sipaviciene, Saule

2010-08-01

278

Effects of high-intensity blood flow restriction exercise on muscle fatigue.  

PubMed

Strength training combined with blood flow restriction (BFR) have been used to improve the levels of muscle adaptation. The aim of this paper was to investigate the acute effect of high intensity squats with and without blood flow restriction on muscular fatigue levels. Twelve athletes (aged 25.95 ± 0.84 years) were randomized into two groups: without Blood Flow Restriction (NFR, n = 6) and With Blood Flow Restriction (WFR, n = 6) that performed a series of free weight squats with 80% 1-RM until concentric failure. The strength of the quadriceps extensors was assessed in a maximum voluntary isometric contraction integrated to signals from the surface electromyogram. The average frequency showed significant reductions in the WFR group for the vastus lateralis and vastus medialis muscles, and intergroup only for the vastus medialis. In conclusion, a set of squats at high intensity with BFR could compromise muscle strength immediately after exercise, however, differences were not significant between groups. PMID:25114743

Neto, Gabriel R; Santos, Heleodório H; Sousa, Juliana B C; Júnior, Adenilson T A; Araújo, Joamira P; Aniceto, Rodrigo R; Sousa, Maria S C

2014-06-28

279

Exercises to Improve Gait Abnormalities  

MedlinePLUS

... Home About Goals Articles Directories Videos Resources Contact Exercises to Improve Gait Abnormalities Home » Article Categories » Exercise and Fitness Font Size: A A A A Exercises to Improve Gait Abnormalities Next Page The manner ...

280

Breast Cancer, Exercise and Acupuncture  

MedlinePLUS Videos and Cool Tools

... the lower right-hand corner of the player. Breast Cancer, Exercise and Acupuncture HealthDay November 12, 2014 Related MedlinePlus Pages Acupuncture Breast Cancer Exercise and Physical Fitness Transcript Exercise therapy and ...

281

Literature: Released Exercises.  

ERIC Educational Resources Information Center

This volume contains 1970-71 Literature assessment exercises (all in the public domain) which have been selected for release at this time by the National Assessment of Educational Progress. Information furnished for each exercise includes: the literature objective it was designed to measure, the theme (section) in which it appears, relevant…

Education Commission of the States, Denver, CO. National Assessment of Educational Progress.

282

Exercise through Menopause.  

ERIC Educational Resources Information Center

Menopause is associated with many different health effects and symptoms. This paper explains that regular exercise can play a critical role in protecting health and battling the increased risk of cardiovascular disease, osteoporosis, pelvic floor atrophy, and joint stiffness associated with menopause. Exercise programs for menopausal women should…

Stuhr, Robyn M.

2002-01-01

283

Heat Loss Calculation Exercise  

NSDL National Science Digital Library

This class exercise from Kirk Garrison is intended for construction students learning about home insulation and heating. The class will learn to calculate heat loss in a home by using an online home heat loss calculator. This exercise document includes student worksheets. This document may be downloaded in PDF file format.

Garrison, Kirk

2012-03-27

284

Name:_____________________________ (Web Exercise)  

E-print Network

Name:_____________________________ (Web Exercise) Model quality, validation exercise. You will need a web link to MolProbity (with Java), and the file 1JIRon1S83_Arg66_supr.kin download- ed from the kinemage.biochem.duke.edu BCH681 web site, or from Sakai. Part 1: MolProbity Go to the MolProbity web

Richardson, David

285

Muscle Na-K-pump and fatigue responses to progressive exercise in normoxia and hypoxia.  

PubMed

To investigate the effects of hypoxia and incremental exercise on muscle contractility, membrane excitability, and maximal Na(+)-K(+)-ATPase activity, 10 untrained volunteers (age = 20 +/- 0.37 yr and weight = 80.0 +/- 3.54 kg; +/- SE) performed progressive cycle exercise to fatigue on two occasions: while breathing normal room air (Norm; Fi(O(2)) = 0.21) and while breathing a normobaric hypoxic gas mixture (Hypox; Fi(O(2)) = 0.14). Muscle samples extracted from the vastus lateralis before exercise and at fatigue were analyzed for maximal Na(+)-K(+)-ATPase (K(+)-stimulated 3-O-methylfluorescein phosphatase) activity in homogenates. A 32% reduction (P < 0.05) in Na(+)-K(+)-ATPase activity was observed (90.9 +/- 7.6 vs. 62.1 +/- 6.4 nmol.mg protein(-1).h(-1)) in Norm. At fatigue, the reductions in Hypox were not different (81 +/- 5.6 vs. 57.2 +/- 7.5 nmol.mg protein(-1).h(-1)) from Norm. Measurement of quadriceps neuromuscular function, assessed before and after exercise, indicated a generalized reduction (P < 0.05) in maximal voluntary contractile force (MVC) and in force elicited at all frequencies of stimulation (10, 20, 30, 50, and 100 Hz). In general, no differences were observed between Norm and Hypox. The properties of the compound action potential, amplitude, duration, and area, which represent the electromyographic response to a single, supramaximal stimulus, were not altered by exercise or oxygen condition when assessed both during and after the progressive cycle task. Progressive exercise, conducted in Hypox, results in an inhibition of Na(+)-K(+)-ATPase activity and reductions in MVC and force at different frequencies of stimulation; these results are not different from those observed with Norm. These changes occur in the absence of reductions in neuromuscular excitability. PMID:15860645

Sandiford, S D; Green, H J; Duhamel, T A; Schertzer, J D; Perco, J D; Ouyang, J

2005-08-01

286

Exercise and functional foods  

PubMed Central

Appropriate nutrition is an essential prerequisite for effective improvement of athletic performance, conditioning, recovery from fatigue after exercise, and avoidance of injury. Nutritional supplements containing carbohydrates, proteins, vitamins, and minerals have been widely used in various sporting fields to provide a boost to the recommended daily allowance. In addition, several natural food components have been found to show physiological effects, and some of them are considered to be useful for promoting exercise performance or for prevention of injury. However, these foods should only be used when there is clear scientific evidence and with understanding of the physiological changes caused by exercise. This article describes various "functional foods" that have been reported to be effective for improving exercise performance or health promotion, along with the relevant physiological changes that occur during exercise. PMID:16749944

Aoi, Wataru; Naito, Yuji; Yoshikawa, Toshikazu

2006-01-01

287

Biomechanical testing of quadriceps tendon–patellar bone grafts: an alternative graft source for press-fit anterior cruciate ligament reconstruction?  

Microsoft Academic Search

Introduction: Press-fit fixation of bone-patellar tendon–bone (BPTB) grafts in anterior cruciate ligament (ACL) reconstruction has been analyzed biomechanically in previous studies; however, the use of quadriceps tendon–patellar bone (QTPB) grafts has not been studied so far. It is hypothesized that QTPB grafts provide primary fixation strength comparable to BPTB grafts in press-fit ACL reconstruction with respect to bone plug length

Jens Dargel; Rüdiger Schmidt-Wiethoff; Thomas Schneider; Gert-Peter Brüggemann; Jürgen Koebke

2006-01-01

288

Anterior cruciate ligament (ACL) reconstruction with quadriceps tendon autograft and press-fit fixation using an anteromedial portal technique  

PubMed Central

Background This article describes an arthroscopic anterior cruciate ligament (ACL) reconstruction technique with a quadriceps tendon autograft using an anteromedial portal technique. Methods A 5?cm quadriceps tendon graft is harvested with an adjacent 2?cm bone block. The femoral tunnel is created through a low anteromedial portal in its anatomical position. The tibial tunnel is created with a hollow burr, thus acquiring a free cylindrical bone block. The graft is then passed through the tibial tunnel and the bone block, customized at its tip, is tapped into the femoral tunnel through the anteromedial portal to provide press-fit fixation. The graft is tensioned distally and sutures are tied over a bone bridge at the distal end of the tibial tunnel. From the cylindrical bone block harvested from the tibia the proximal end is customized and gently tapped next to the graft tissue into the tibial tunnel to assure press fitting of the graft in the tibial tunnel. The distal part of the tibial tunnel is filled up with the remaining bone. All patients were observed in a prospective fashion with subjective and objective evaluation after 6?weeks, 6 and 12?months. Results Thirty patients have been evaluated at a 12?months follow-up. The technique achieved in 96.7% normal or nearly normal results for the objective IKDC. The mean subjective IKDC score was 86.1 ± 15.8. In 96.7% the Tegner score was the same as before injury or decreased one category. A negative or 1+ Lachman test was achieved in all cases. Pivot-shift test was negative or (+) glide in 86.7%. The mean side-to-side difference elevated by instrumental laxity measurement was 1.6 ± 1.1?mm. Full ROM has been achieved in 92.3%. The mean single one-leg-hop index was 91.9 ± 8.0 at the follow-up. Conclusions Potential advantages include minimum bone loss specifically on the femoral side and graft fixation without implants. PMID:22925587

2012-01-01

289

Strengthening the Canadian alcohol advertising regulatory system.  

PubMed

Research evidence points to harmful effects from alcohol advertising among children and youth. In particular, exposure to alcohol advertising has been associated with adolescents drinking both earlier and heavier. Although current federal and provincial guidelines have addressed advertising practices to prevent underage drinking, practice has not been supported by existing policy. While protective measures such as social marketing campaigns have the potential for counteracting the effects from alcohol advertising, the effectiveness of such measures can be easily drowned out with increasing advertising activities from the alcohol industry, especially without effective regulation. Research reviewed by the European Focus on Alcohol Safe Environment (FASE) Project has identified a set of key elements that are necessary to make alcohol advertising policy measures effective at protecting children and youth from the harmful effects of alcohol marketing. Using these key elements as an evaluation framework, there are critical components in the Canadian alcohol advertising regulatory system that clearly require strengthening. To protect impressionable children and youth against the harmful effects of alcohol advertising, 13 recommendations to strengthen current alcohol advertising regulations in Canada are provided for Canadian policy-makers, advertising standard agencies, and public health groups. PMID:23618638

Heung, Carly M; Rempel, Benjamin; Krank, Marvin

2012-01-01

290

Using exercises to improve public health preparedness in Asia, the Middle East and Africa  

PubMed Central

Background Exercises are increasingly common tools used by the health sector and other sectors to evaluate their preparedness to respond to public health threats. Exercises provide an opportunity for multiple sectors to practice, test and evaluate their response to all types of public health emergencies. The information from these exercises can be used to refine and improve preparedness plans. There is a growing body of literature about the use of exercises among local, state and federal public health agencies in the United States. There is much less information about the use of exercises among public health agencies in other countries and the use of exercises that involve multiple countries. Results We developed and conducted 12 exercises (four sub-national, five national, three sub-regional) from August 2006 through December 2008. These 12 exercises included 558 participants (average 47) and 137 observers (average 11) from 14 countries. Participants consistently rated the overall quality of the exercises as very good or excellent. They rated the exercises lowest on their ability to identifying key gaps in performance. The vast majority of participants noted that they would use the information they gained at the exercise to improve their organization’s preparedness to respond to an influenza pandemic. Participants felt the exercises were particularly good at raising awareness and understanding about public health threats, assisting in evaluating plans and identifying priorities for improvement, and building relationships that strengthen preparedness and response across sectors and across countries. Participants left the exercises with specific ideas about the most important actions that they should engage in after the exercise such as improved planning coordination across sectors and countries and better training of health workers and response personnel. Conclusions These experiences suggest that exercises can be a valuable, low-burden tool to improve emergency preparedness and response in countries around the world. They also demonstrate that countries can work together to develop and conduct successful exercises designed to improve regional preparedness to public health threats. The development of standardized evaluation methods for exercises may be an additional tool to help focus the actions to be taken as a result of the exercise and to improve future exercises. Exercises show great promise as tools to improve public health preparedness across sectors and countries. PMID:25063987

2014-01-01

291

Writing Strengthens Orthography and Alphabetic-Coding Strengthens Phonology in Learning to Read Chinese  

ERIC Educational Resources Information Center

Learning to write words may strengthen orthographic representations and thus support word-specific recognition processes. This hypothesis applies especially to Chinese because its writing system encourages character-specific recognition that depends on accurate representation of orthographic form. We report 2 studies that test this hypothesis in…

Guan, Connie Qun; Liu, Ying; Chan, Derek Ho Leung; Ye, Feifei; Perfetti, Charles A.

2011-01-01

292

SCHNERCH, "Design Guidelines for Strengthening Steel Beams", 1/10 DESIGN GUIDELINES FOR STRENGTHENING OF  

E-print Network

FOR STRENGTHENING OF STEEL-CONCRETE COMPOSITE BEAMS WITH HIGH MODULUS CFRP MATERIALS David Schnerch Wiss, Janney for High Modulus Carbon Fiber Material Property Fiber Laminate Ultimate Strain 0.004 0.0033 Tensile Modulus University, USA Abstract This paper proposes guidelines for the design and installation of high modulus

293

Assessment of magnetic resonance techniques to measure muscle damage 24?h after eccentric exercise.  

PubMed

The study examined which of a number of different magnetic resonance (MR) methods were sensitive to detecting muscle damage induced by eccentric exercise. Seventeen healthy, physically active participants, with muscle damage confirmed by non-MR methods were tested 24?h after performing eccentric exercise. Techniques investigated whether damage could be detected within the quadriceps muscle as a whole, and individually within the rectus femoris, vastus lateralis (VL), vastus medialis (VM), and vastus intermedius (VI). Relative to baseline values, significant changes were seen in leg and muscle cross-sectional areas and volumes and the resting inorganic phosphate concentration. Significant time effects over all muscles were also seen in the transverse relaxation time (T2) and apparent diffusion coefficient (ADC) values, with individually significant changes seen in the VL, VM, and VI for T2 and in the VI for ADC. A significant correlation was found between muscle volume and the average T2 change (r?=?0.59) but not between T2 and ADC or Pi alterations. There were no significant time effects over all muscles for magnetization transfer contrast images, for baseline pH, phosphocreatine (PCr), phosphodiester, or ATP metabolite concentrations or the time constant describing the rate of PCr recovery following exercise. PMID:24738493

Fulford, J; Eston, R G; Rowlands, A V; Davies, R C

2015-02-01

294

Geologic Mapping Exercise  

NSDL National Science Digital Library

This exercise is designed to simulate how a basic geological investigation of a site takes place. A basic geological investigation includes familiarizing yourself with the unconsolidated sediments, rocks, structural geology, and groundwater present at your site. As part of this exercise you will have to properly identify a variety of rock types and sediments, create maps that represent data you collected at each location, and complete a basic report of your findings (optional). Once completed, this exercise should give students a basic understanding of how the various concepts used throughout the semester are applied in the real world in the form of a geological investigation.

Andrew Smith

295

[Exercise-induced asthma].  

PubMed

Exercise-induced asthma is characterized by a transient rise of the airways resistances, associated with asthmatic symptoms, 5 to 10 minutes after the end of a submaximal effort. The treatment is based on a pre-effort warming, cover the mouth with a mask (when the weather is cold), the use of beta-mimetic bronchodilators before exercise and, chronic treatment with antiinflammatory drugs. When the patient is not controlled, an evaluation of the lung function is required with a postbronchodilator control or an exercise challenge test. If the patient remains uncontrolled despite the treatment, others diagnostics should be excluded, such as vocal cords dysfunction or left heart failure. PMID:21089401

Michel, O

2010-09-01

296

The highest antagonistic coactivation of the vastus intermedius muscle among quadriceps femoris muscles during isometric knee flexion.  

PubMed

Although the possibility that the vastus intermedius (VI) muscle contributes to flexion of the knee joint has been suggested previously, the detail of its functional role in knee flexion is not well understood. The purpose of this study was to examine the antagonist coactivation of VI during isometric knee flexion. Thirteen men performed 25-100% of maximal voluntary contraction (MVC) at 90°, 120°, and 150° knee joint angles. Surface electromyography (EMG) of the four individual muscles in the quadriceps femoris (QF) was recorded and normalized by the EMG signals during isometric knee extension at MVC. Cross-talk on VI EMG signal was assessed based on the median frequency response to selective cooling of hamstring muscles. Normalized EMG of the VI was significantly higher than that of the other synergistic QF muscles at each knee joint angle (all P<0.05) with minimum cross-talk from the hamstrings to VI. There were significant correlations between the EMG signal of the hamstrings and VI (r=0.55-0.85, P<0.001). These results suggest that VI acts as a primary antagonistic muscle of QF during knee flexion, and that VI is presumably a main contributor to knee joint stabilization. PMID:23489717

Saito, Akira; Watanabe, Kohei; Akima, Hiroshi

2013-08-01

297

Effect of a short time concentric versus eccentric training program on electromyography activity and peak torque of quadriceps.  

PubMed

The purpose of this study was to examine the effect of an 8-week concentric (CON) versus eccentric (ECC) isokinetic training program on the electromyography (EMG) signal amplitude of vastus medialis (VM), vastus lateralis (VL) and rectus femoris (RF). Also, the isometric (ISO) and dynamic maximum strength of the knee extensors were assessed. Eighteen physically healthy male subjects (age 22 ± 1 years, body height 177 ± 4 cm, body mass 73 ± 7 kg) performed four weeks of unilateral CON isokinetic training for the quadriceps of the dominant leg on a REV9000 dynamometer. At the end of the fourth week, the sample was divided into two groups, with one group performing additional four weeks of unilateral ECC training and the other continuing with CON training. The training sessions consisted of three sets of ten maximal repetitions at a velocity of 60ºs-1, three days per week for eight weeks. The results showed that CON and ECC groups improved the peak torque in all types of contractions. Also, both groups presented increases in the avgEMG for VL, VM and RF. The present investigation showed that CON training elicited increases of the ISO peak torque and VM avgEMG in the CON contraction. Additionally, significant gains were reported after the ECC training on the VM avgEMG in all contractions and RM avgEMG in CON contraction. PMID:25114726

Carvalho, Alberto; Caserotti, Paolo; Carvalho, Carlos; Abade, Eduardo; Sampaio, Jaime

2014-06-28

298

Feedback controlled force enhancement and activation reduction of voluntarily activated quadriceps femoris during sub-maximal muscle action.  

PubMed

Stretch of activated muscles leads to enhanced forces compared to isometric contractions at the same muscle length and the same level of activation. This so-called residual force enhancement (RFE) is thought to be a property of all muscles and preparations. However, observations concerning the existence, amount and duration of RFE are inconsistent, especially for voluntary activated large human muscles. Therefore, physiological relevance for daily activity is still questionable and the purpose of this study was to examine whether RFE is present in voluntary sub-maximal activated quadriceps femoris (QF). Seated in a rotational dynamometer with EMG attached to superficial parts of QF, 30 subjects performed isometric and isometric-eccentric-isometric contractions (20° stretch, ?=60°s(-1)) at 30% and 60% of maximum voluntary activation (MVA) and contraction (MVC). To account for the complexity of the multi-headed QF, a compensation model based on physiological cross-sectional area and individual EMG-torque relations was used to interpret EMG data. For both levels of intensity and both feedback control strategies, ANOVA identified significant RFE (at the same level of activation) and reduced activation (at the same level of torque). Against expectations, RFE was independent of the level of activation. PMID:22115525

Seiberl, Wolfgang; Hahn, Daniel; Herzog, Walter; Schwirtz, Ansgar

2012-02-01

299

A guide to exercise prescription.  

PubMed

Exercise is a fundamental component of good health. The American College of Sports Medicine and "Exercise is Medicine" recommend treating exercise as a vital sign, and assessing and prescribing physical activity at every medical visit. Meeting the recommended goals of physical activity results in a significant reduction in all-cause mortality. Physicians can improve health by prescribing exercise. PMID:24209719

Crookham, Jason

2013-12-01

300

Exercise training in pulmonary rehabilitation.  

PubMed

Exercise training remains a cornerstone of pulmonary rehabilitation (PR) in patients with chronic respiratory disease. The choice of type of exercise training depends on the physiologic requirements and goals of the individual patient as well as the available equipment at the PR center. Current evidence suggests that, at ground walking exercise training, Nordic walking exercise training, resistance training, water-based exercise training, tai chi, and nonlinear periodized exercise are all feasible and effective in (subgroups) of patients with chronic obstructive pulmonary disease. In turn, these exercise training modalities can be considered as part of a comprehensive, interdisciplinary PR program. PMID:24874127

Andrianopoulos, Vasileios; Klijn, Peter; Franssen, Frits M E; Spruit, Martijn A

2014-06-01

301

Plant volatile analogues strengthen attractiveness to insect.  

PubMed

Green leaf bug Apolygus lucorum (Meyer-Dür) is one of the major pests in agriculture. Management of A. lucorum was largely achieved by using pesticides. However, the increasing population of A. lucorum since growing Bt cotton widely and the increased awareness of ecoenvironment and agricultural product safety makes their population-control very challenging. Therefore this study was conducted to explore a novel ecological approach, synthetic plant volatile analogues, to manage the pest. Here, plant volatile analogues were first designed and synthesized by combining the bioactive components of ?-ionone and benzaldehyde. The stabilities of ?-ionone, benzaldehyde and analogue 3 g were tested. The electroantennogram (EAG) responses of A. lucorum adult antennae to the analogues were recorded. And the behavior assay and filed experiment were also conducted. In this study, thirteen analogues were acquired. The analogue 3 g was demonstrated to be more stable than ?-ionone and benzaldehyde in the environment. Many of the analogues elicited EAG responses, and the EAG response values to 3 g remained unchanged during seven-day period. 3 g was also demonstrated to be attractive to A. lucorum adults in the laboratory behavior experiment and in the field. Its attractiveness persisted longer than ?-ionone and benzaldehyde. This indicated that 3 g can strengthen attractiveness to insect and has potential as an attractant. Our results suggest that synthetic plant volatile analogues can strengthen attractiveness to insect. This is the first published study about synthetic plant volatile analogues that have the potential to be used in pest control. Our results will support a new ecological approach to pest control and it will be helpful to ecoenvironment and agricultural product safety. PMID:24911460

Sun, Yufeng; Yu, Hao; Zhou, Jing-Jiang; Pickett, John A; Wu, Kongming

2014-01-01

302

Exercise-Induced Bronchoconstriction  

MedlinePLUS

... experience symptoms only when they exercise. Symptoms include: • Shortness of breath • Coughing • Wheezing • Tight chest These symptoms are often worse in cold, dry air. Warm and humid air may lessen ...

303

Kids and Exercise  

MedlinePLUS

... just 1-2 hours a day of quality programming How Much Exercise Is Enough? Parents should make ... Privacy Policy & Terms of Use Visit the Nemours Web site. Note: All information on KidsHealth® is for ...

304

Exercise Tips for Travelers  

MedlinePLUS

... Tips for Travelers Whether you’re traveling for business or pleasure, you can stick to your exercise ... you’re on vacation, but even on a business trip, it’s possible to squeeze in 30 minutes ...

305

Exercises in Physical Oceanography  

NSDL National Science Digital Library

This site from Flinders University in Australia features two sets of exercises that accompany a course on physical oceanography. The basic exercises were originally intended to replace the need for the teacher's presence, but have since also proved useful in distance learning. Topics for these exercises include map projections ocean floor topography, properties of sea water, and water masses and tides. The advanced exercises were designed to give deeper insight into the material and to encourage investigation. Advanced topics include coastal upwelling, graphic display methods for ocean currents, averaging methods for vector time series, geostrophic currents, Rossby wave propagation, the depth of the permanent thermocline (the Sverdrup balance), Ekman layer dynamics, and the outflow of Mediterranean Water into the Atlantic Ocean. The site also features links to other oceanography websites.

Tomczak, Matthias; Flinders University, Australia

306

Exercise and children  

MedlinePLUS

... Playing organized sports (such as soccer, basketball, and football) Younger children have a shorter attention span than ... or biking. Others prefer group sports, like soccer, football, or basketball. Choose an exercise that works well ...

307

Why Exercise Is Cool  

MedlinePLUS

... else counts as exercise? Playing sports, dancing, doing push-ups, and even reaching down to touch your toes. ... your muscles stronger. Did you ever do a push-up or swing across the monkey bars at the ...

308

Exercise in Inquiry  

NSDL National Science Digital Library

Students expressed strong positive feelings about inquiry-based teaching methods the authors developed and implemented in an undergraduate exercise physiology laboratory course. Inquiry-based learning resulted in a higher order of learning not typically o

Cheryl L. Mason

2003-03-01

309

Hand and Finger Exercises  

MedlinePLUS

... vision and language needs, call (614) 293-3191. Hand and Finger Exercises ? Place your palm flat on ... times for ____ seconds. ? Pick up objects with your hand. Start out with larger objects. Repeat ____ times for ____ ...

310

The "Friendly Student" Exercise.  

ERIC Educational Resources Information Center

Uses a class exercise that tests the folk wisdom concerning small-town friendliness. Students are assigned to express random friendliness to strangers so they can determine whether friendlier responses are elicited in small towns or large cities. (KO)

Wright, Richard A.

1989-01-01

311

Adventures in Exercise Physiology  

NSDL National Science Digital Library

The author altered the format of an exercise physiology course from traditional lecture to emphasizing daily reading quizzes and group problem-solving activities. The SALGains evaluation was used to compare the two approaches and significant improvements

Kathleen A. FitzPatrick

2004-09-01

312

Exercise 6: Cartography  

NSDL National Science Digital Library

Barbara and David Tewksbury, Hamilton College Summary In the first part of the exercise, students examine a variety of ArcMaps to work out what data sets and techniques were used and to develop a list of the ...

Tewksbury, Barb

313

Exercise-Induced Bronchospasm  

MedlinePLUS

... air that is cooler and drier than the air in your lungs during exercise may cause EIB. If you have EIB and chronic asthma, your symptoms may get worse during spring and fall, when people tend to have trouble ...

314

Exercise interventions: defusing the world's osteoporosis time bomb.  

PubMed Central

Osteoporosis is a major public health problem, affecting millions of people worldwide. The associated health care costs are growing in parallel with increases in elderly populations, and it is expected that the number of osteoporotic fractures will double over the next 50 years. The best way to address osteoporosis is prevention. Some interventions to maximize and preserve bone mass have multiple health benefits and are cost-effective. For example, modifications to diet and lifestyle can help to prevent osteoporosis, and could potentially lead to a significant decrease in fracture rates; and exercise is a valuable adjunct to programmes aimed at alleviating the risks and symptoms of osteoporosis. Practising exercise at a young age helps maximize the mineral density of bones while they are still growing and maturing, and continuing to excercise minimizes bone loss later in life. Not only does exercise improve bone health, it also increases muscle strength, coordination, balance, flexibility and leads to better overall health. Walking, aerobic exercise, and t'ai chi are the best forms of exercise to stimulate bone formation and strengthen the muscles that help support bones. Encouraging physical activity at all ages is therefore a top priority to prevent osteoporosis. PMID:14758410

Kai, Ming Chan; Anderson, Mary; Lau, Edith M. C.

2003-01-01

315

Inverted Troughs Case Exercise  

NSDL National Science Digital Library

This exercise follows the progression of a winter weather event across the Central Plains states beginning 1200 UTC on 7 March 1999. Each forecast question is accompanied by Eta model data and includes a forecast discussion by Phil Schumacher, NWS Sioux Falls, South Dakota. This exercise compliments the Webcast, Inverted Troughs and their Associated Precipitation Regimes, based on a presentation by Phil Schumacher at the MSC Winter Weather Course, December 2002, in Boulder Colorado.

Comet

2004-01-29

316

Effects of acute exercise on attenuated vagal baroreflex function during bed rest  

NASA Technical Reports Server (NTRS)

We measured carotid baroreceptor-cardiac reflex responses in six healthy men, 24 h before and 24 h after a bout of leg exercise during 6 deg head-down bed rest to determine if depressed vagal baroreflex function associated with exposure to microgravity environments could be reversed by a single exposure to acute intense exercise. Baroreflex responses were measured before bed rest and on day 7 of bed rest. An exercise bout consisting of dynamic and isometric actions of the quadriceps at graded speeds and resistances was performed on day 8 of bed rest and measurements of baroreflex response were repeated 24 h later. Vagally-mediated cardiac responses were provoked with ramped neck pressure-suction sequences comprising pressure elevations to +40 mm Hg, followed by serial, R-wave triggered 15 mm Hg reductions, to -65 mm Hg. Baroreceptor stimulus-cardiac response relationships were derived by plotting each R-R interval as a function of systolic pressure less the neck chamber pressure applied during the interval. Compared with pre-bed rest baseline measurements, 7 d of bed rest decreased the gain (maximum slope) of the baroreflex stimulus-response relationship by 16.8 +/- 3.4 percent (p less than 0.05). On day 9 of bed rest, 24 h after exercise, the maximum slope of the baroreflex stimulus-response relationship was increased (p less than 0.05) by 10.7 +/- 3.7 percent above pre-bed rest levels and 34.3 +/- 7.9 percent above bed rest day 7. Our data verify that vagally-mediated baroreflex function is depressed by exposure to simulated microgravity and demonstrate that this effect can be acutely reversed by exposure to a single bout of intense exercise.

Convertino, Victor A.; Doerr, Donald F.; Guell, Antonio; Marini, J.-F.

1992-01-01

317

Body Temperatures During Exercise in Deconditioned Dogs: Effect of NACL and Glucose Infusion  

NASA Technical Reports Server (NTRS)

Infusion of glucose (Glu) into normal exercising dogs attenuates the rise in rectal temperature (Delta-Tre) when compared with delta-Tre during FFA infusion or no infusion. Rates of rise and delta-=Tre levels are higher during exercise after confinement. Therefore, the purpose of this study was to determine if Glu infusion would attenuate the exercise-induced excess hyperthermia after deconditioning. Rectal and quadricep femoris muscle temperatures (Tmu) were measured in 7 male, mongrel dogs dogs (19.6 +/- SD 3.0 kg) during 90 minutes of treadmill exercise (3.1 +/-SD 0.2 W/kg) with infusion (30ml/min/kg) of 40% Glu or 0.9% NaCL before BC) and after confinement (AC) in cages (40 x 110 x 80 cm) for 8 wk. Mean (+/-SE body wt. were 19.6 +/- 1.1 kg BC and 19.5 +/- 1.1kg AC, exercise VO2 were not different (40.0 - 42.0 mi/min/kg-1). With NaCl AC, NaCl BC, GluAC, and GluBC: Delta-Tre were, 1.8, 1.4, 1.3 and 0.9C respectively; and Delta-Tmu were 2.3, 1.9, 1.6, and 1.4C. respectively (P<0.05 from GluBC). Compared with NaCl infusion, attenuated both Delta-Tre and Delta-Tmu BC and AC, respectively. Compared with GluBC, GluAC attenuated Delta-Tmu but not Delta-Tre. Thus. with similar heat production, the mechanism for attenuation at bad body temperature with Glu infusion must affect avenues of heat dissipation.

Greenleaf, J. E.; Kruk, B.; Nazar, K.; Kaciuba-Usciko, H.

2000-01-01

318

cAMP levels in fast- and slow-twitch skeletal muscle after an acute bout of aerobic exercise  

NASA Technical Reports Server (NTRS)

The present study examined whether exercise duration was associated with elevated and/or sustained elevations of postexercise adenosine 3',5'-cyclic monophosphate (cAMP) by measuring cAMP levels in skeletal muscle for up to 4 h after acute exercise bouts of durations that are known to either produce (60 min) or not produce (10 min) mitochondrial proliferation after chronic training. Treadmill-acclimatized, but untrained, rats were run at 22 m/min for 0 (control), 10, or 60 min and were killed at various postexercise (0, 0.5, 1, 2, and 4 h) time points. Fast-twitch white and red (quadriceps) and slow-twitch (soleus) muscles were quickly excised, frozen in liquid nitrogen, and assayed for cAMP with a commercial kit. Unexpectedly, cAMP contents in all three muscles were similar to control (nonexercise) at most (21 of 30) time points after a single 10- or 60-min run. Values at 9 of 30 time points were significantly different from control (P < 0.05); i.e., 3 time points were significantly higher than control and 6 were significantly less than control. These data suggest that the cAMP concentration of untrained skeletal muscle after a single bout of endurance-type exercise is not, by itself, associated with exercise duration.

Sheldon, A.; Booth, F. W.; Kirby, C. R.

1993-01-01

319

Implications of group III and IV muscle afferents for high-intensity endurance exercise performance in humans.  

PubMed

We investigated the influence of group III/IV muscle afferents on peripheral fatigue, central motor drive (CMD) and endurance capacity during high-intensity leg-cycling. In a double-blind, placebo-controlled design, seven males performed constant-load cycling exercise (318 ± 9 W; 80% of peak power output (W(peak))) to exhaustion under placebo conditions and with lumbar intrathecal fentanyl impairing spinal ?-opioid receptor-sensitive group III/IV muscle afferents. Peripheral fatigue was assessed via changes in pre- vs. post-exercise quadriceps force in response to supramaximal magnetic femoral nerve stimulation (?Q(tw,pot)). CMD was estimated via quadriceps electromyogram. To rule out a direct central effect of fentanyl, we documented unchanged resting cardioventilatory responses. Compared to placebo, significant hypoventilation during the fentanyl trial was indicated by the 9% lower V(E)/V(CO(2)), causing a 5 mmHg increase in end-tidal P(CO(2)) and a 3% lower haemoglobin saturation. Arterial pressure and heart rate averaged 8 and 10% lower, respectively, during the fentanyl trial and these differences progressively diminished towards end-exercise. Although initially similar, the percent change in CMD was 9 ± 3% higher at end-exercise with fentanyl vs. placebo (P < 0.05). Time to exhaustion was shorter (6.8 ± 0.3 min vs. 8.7 ± 0.3 min) and end-exercise ?Q(tw,pot) was about one-third greater (-44 ± 2% vs. -34 ± 2%) following fentanyl vs. placebo. The rate of peripheral fatigue development was 67 ± 10% greater during the fentanyl trial (P < 0.01). Our findings suggest that feedback from group III/IV muscle afferents limits CMD but also minimizes locomotor muscle fatigue development by stimulating adequate ventilatory and circulatory responses to exercise. In the face of blocked group III/IV muscle afferents, CMD is less inhibited but O(2) transport compromised and locomotor muscle fatigability is exacerbated with a combined net effect of a reduced endurance performance. PMID:21878520

Amann, Markus; Blain, Gregory M; Proctor, Lester T; Sebranek, Joshua J; Pegelow, David F; Dempsey, Jerome A

2011-11-01

320

Pediatric endurance and limb strengthening for children with cerebral palsy (PEDALS) – a randomized controlled trial protocol for a stationary cycling intervention  

PubMed Central

Background In the past, effortful exercises were considered inappropriate for children with spastic cerebral palsy (CP) due to concern that they would escalate abnormalities including spasticity and abnormal movement patterns. Current scientific evidence indicates that these concerns were unfounded and that therapeutic interventions focused on muscle strengthening can lead to improved functional ability. However, few studies have examined the potential benefits of cardiorespiratory fitness exercises in this patient population. Methods/design The rationale and design of a randomized controlled trial examining the effects of a stationary cycling intervention for children with CP are outlined here. Sixty children with spastic diplegic CP between the ages of 7 and 18 years and Gross Motor Function Classification System (GMFCS) levels of I, II, or III will be recruited for this study. Participants will be randomly assigned to either an intervention (cycling) or a control (no cycling) group. The cycling intervention will be divided into strengthening and cardiorespiratory endurance exercise phases. During the strengthening phase, the resistance to lower extremity cycling will be progressively increased using a uniquely designed limb-loaded mechanism. The cardiorespiratory endurance phase will focus on increasing the intensity and duration of cycling. Children will be encouraged to exercise within a target heart rate (HR) range (70 – 80% maximum HR). Thirty sessions will take place over a 10–12 week period. All children will be evaluated before (baseline) and after (follow-up) the intervention period. Primary outcome measures are: knee joint extensor and flexor moments, or torque; the Gross Motor Function Measure (GMFM); the 600 Yard Walk-Run test and the Thirty-Second Walk test (30 sec WT). Discussion This paper presents the rationale, design and protocol for Pediatric Endurance and Limb Strengthening (PEDALS); a Phase I randomized controlled trial evaluating the efficacy of a stationary cycling intervention for children with spastic diplegic cerebral palsy. PMID:17374171

Fowler, Eileen G; Knutson, Loretta M; DeMuth, Sharon K; Sugi, Mia; Siebert, Kara; Simms, Victoria; Azen, Stanley P; Winstein, Carolee J

2007-01-01

321

Efficacy of pre-exercise low-level laser therapy on isokinetic muscle performance in individuals with type 2 diabetes mellitus: study protocol for a randomized controlled trial  

PubMed Central

Background Type 2 diabetes, also known non-insulin-dependent diabetes, is the most prevalent type of the disease and involves defects in the secretion and action of insulin. The aim of the proposed study is to evaluate the efficacy of pre-exercise low-level laser therapy (LLLT) on muscle performance of the quadriceps femoris in individuals with type 2 diabetes. Methods/Design A double-blind, randomized, controlled clinical trial will be carried out in two treatment phases. In the first phase, quadriceps muscle performance will be evaluated using an isokinetic dynamometer and the levels of creatine kinase and lactate dehydrogenase (biochemical markers of muscle damage) will be determined. The participants will then be allocated to four LLLT groups through a randomization process using opaque envelopes: Group A (4 Joules), Group B (6 Joules), Group C (8 Joules) and Group D (0 Joules; placebo). Following the administration of LLLT, the participants will be submitted to an isokinetic eccentric muscle fatigue protocol involving the quadriceps muscle bilaterally. Muscle performance and biochemical markers of muscle damage will be evaluated again immediately after as well as 24 and 48 hours after the experimental protocol. One week after the last evaluation the second phase will begin, during which Groups A, B and C will receive the LLLT protocol that achieved the best muscle performance in phase 1 for a period of 4 weeks. At the end of this period, muscle performance will be evaluated again. The protocol for this study is registered with the World Health Organization under Universal Trial Number U1111-1146-7109. Discussion The purpose of this randomized clinical trial is to evaluate the efficacy of pre-exercise LLLT on the performance of the quadriceps muscle (peak torque, total muscle work, maximum power and fatigue index – normalized by body mass) in individuals with DM-2. The study will support the practice of evidence-based to the use of LLLT in improving muscle performance in Individuals with DM-2. Data will be published after the study is completed. PMID:24716713

2014-01-01

322

Research capacity strengthening in the South.  

PubMed

Active promotion of evidence-based decision-making at all levels of the health field is a necessary step in the direction of improving the health of the population. Recent studies have shown that the burden of disease in developing countries is high particularly the burden of infectious, communicable and non-communicable diseases and health problems of mothers and children. There is presently, a mismatch between this increased disease and health burden and the technical and human capacity of developing countries to use existing knowledge and to generate new knowledge to combat these diseases and health problems. It is therefore necessary to assist developing countries to build indigenous research capability so they can undertake studies in their own national settings the results of which will lead to the development of appropriate control strategies in their countries. Building indigenous research capacity will enable developing country scientists to translate results of studies carried out elsewhere into their individual national settings. Eventually results of such studies will increase the global knowledge base about the particular health problems and contribute to finding appropriate solutions to them. The research will, finally, increase knowledge-based decision-making by their health leadership of the country. This paper has set out to describe some experiences in capacity strengthening over the last few decades and to propose from these, mechanisms for building these capacities in a sustainable manner. This paper has described the steps in capability strengthening with special emphasis on identification of trainees, their training and deployment on return. The paper has described mechanisms of research sustainability including creation of suitable career structures, remuneration of researchers and the importance of building up suitable infrastructure for research to meet increasing demands and competence. The place of partnerships South-South, South-North and networking has been stressed. Finally, the paper calls for greater involvement by policy makers in developing countries in the entire capacity building process. They should set highly focussed research priorities, identify competence not already existing and proceed to fill these gaps along the lines described. PMID:12113452

Nchinda, Thomas C

2002-06-01

323

FINITE ELEMENT MODELING OF RC CONNECTIONS STRENGTHENED WITH FRP LAMINATES  

Microsoft Academic Search

Use of fiber reinforced plastic (FRP) composites for strengthening of beams and columns in RC structures has attracted great attention in recent decades. However, less attention has been paid to strengthening RC connections with FRP laminates. In the current study, a finite element (FE) modeling has been proposed for the non-linear analysis of RC joints covered with FRP overlays. The

D. MOSTOFINEJAD; S. B. TALAEITABA

324

Shear capacity of FRP-strengthened RC beams: FRP debonding  

Microsoft Academic Search

Many studies have been undertaken on shear strengthening of reinforced concrete (RC) beams by externally bonding fibre-reinforced polymer (FRP) composites. These studies have established clearly that such strengthened beams fail in shear mainly in one of two modes: FRP rupture; and FRP debonding, and have led to preliminary design proposals. This paper is concerned with the development of a simple,

J. F. Chen; J. G. Teng

2003-01-01

325

BEHAVIOR OF INFILL MASONRY WALLS STRENGTHENED WITH FRP MATERIALS  

E-print Network

BEHAVIOR OF INFILL MASONRY WALLS STRENGTHENED WITH FRP MATERIALS D.S. Lunn 1,2 , V. Hariharan 1 , G of the research program presented in this paper is to evaluate the effectiveness of strengthening infill masonry) that was in-filled with solid concrete brick masonry. The specimens were loaded by out-of-plane uniformly

326

Shear behavior of masonry panels strengthened by FRP laminates  

Microsoft Academic Search

The present experimental study, performed on brick masonry panels strengthened by Fiber Reinforced Polymer (FRP) laminates, was aimed to investigate the efficiency of an alternative shear reinforcement technique. A series of nine unreinforced masonry (URM) panels and 24 strengthened panels have been subjected to diagonal compression tests. Different reinforcement configurations were evaluated. Experimental results pointed out that FRP reinforcement applied

M. R. Valluzzi; D. Tinazzi; C. Modena

2002-01-01

327

1 STANDARD AND REGULATION FOR SEISMIC STRENGTHENING AND  

E-print Network

1 STANDARD AND REGULATION FOR SEISMIC STRENGTHENING AND RETROFITING Seismic Evaluation Standard beam and steel tensile bar Seismic assessment and retrofit of Beijing engineering in the capital area.C. workshop Comprehensive Stage: in addition to seismic strengthening and retrofitting (1) Extension

Spencer Jr., B.F.

328

Local theorems in strengthened form for lattice random variables.  

NASA Technical Reports Server (NTRS)

Investigation of some conditions which are sufficient for a sequence of independent integral-valued lattice random variables to satisfy a local theorem in strengthened form. A number of theorems giving the conditions under which the investigated sequence satisfies a local theorem in strengthened form are proven with the aid of lemmas derived by Kruglov (1968).

Mason, J. D.

1971-01-01

329

Molecular profiles of Quadriceps muscle in myostatin-null mice reveal PI3K and apoptotic pathways as myostatin targets  

PubMed Central

Background Myostatin (MSTN), a member of the TGF-? superfamily, has been identified as a negative regulator of skeletal muscle mass. Inactivating mutations in the MSTN gene are responsible for the development of a hypermuscular phenotype. In this study, we performed transcriptomic and proteomic analyses to detect altered expression/abundance of genes and proteins. These differentially expressed genes and proteins may represent new molecular targets of MSTN and could be involved in the regulation of skeletal muscle mass. Results Transcriptomic analysis of the Quadriceps muscles of 5-week-old MSTN-null mice (n = 4) and their controls (n = 4) was carried out using microarray (human and murine oligonucleotide sequences) of 6,473 genes expressed in muscle. Proteomic profiles were analysed using two-dimensional gel electrophoresis coupled with mass spectrometry. Comparison of the transcriptomic profiles revealed 192 up- and 245 down- regulated genes. Genes involved in the PI3K pathway, insulin/IGF pathway, carbohydrate metabolism and apoptosis regulation were up-regulated. Genes belonging to canonical Wnt, calcium signalling pathways and cytokine-receptor cytokine interaction were down-regulated. Comparison of the protein profiles revealed 20 up- and 18 down-regulated proteins spots. Knockout of the MSTN gene was associated with up-regulation of proteins involved in glycolytic shift of the muscles and down-regulation of proteins involved in oxidative energy metabolism. In addition, an increased abundance of survival/anti-apoptotic factors were observed. Conclusion All together, these results showed a differential expression of genes and proteins related to the muscle energy metabolism and cell survival/anti-apoptotic pathway (e.g. DJ-1, PINK1, 14-3-3? protein, TCTP/GSK-3?). They revealed the PI3K and apoptotic pathways as MSTN targets and are in favour of a role of MSTN as a modulator of cell survival in vivo. PMID:19397818

Chelh, Ilham; Meunier, Bruno; Picard, Brigitte; Reecy, Mark James; Chevalier, Catherine; Hocquette, Jean-François; Cassar-Malek, Isabelle

2009-01-01

330

Joining of Oxide Dispersion Strengthened Steels for Advanced Reactors  

NASA Astrophysics Data System (ADS)

The design, manufacture, and experimental analysis of structural materials capable of operation in the high temperatures, corrosive environments, and radiation damage spectra of future reactor designs remain one of the key pacing items for advanced reactor designs. The most promising candidate structural materials are vanadium-based refractory alloys, silicon carbide composites and oxide dispersion strengthened steels. Of these, oxide dispersion strengthened steels are a likely near-term candidate to meet required demands. This paper reviews different variants of oxide dispersion strengthened steels and discusses their capability with regard to high-temperature strength, corrosion resistance, and radiation damage resistance. Additionally, joining of oxide dispersion strengthened steels, which has been cited as a limiting factor preventing their use, is addressed and reviewed. Specifically, friction stir welding of these steels is reviewed as a promising joining method for oxide dispersion strengthened steels.

Baker, B. W.; Brewer, L. N.

2014-12-01

331

Prescribed aerobic exercise and the recovery from traumatic brain injuries (TBI) among children and adolescents: A Randomised Controlled Trial Protocol  

Microsoft Academic Search

Children with moderate and severe traumatic brain injuries often have associated physical impairments such as muscle weakness, incoordination, and spasticity as long term sequelae of their injury. The current practice is to provide an individualised therapy program consisting of retraining of motor tasks, specific muscle strengthening and coordination exercises, and fitness and balance activities. However the use of an aerobic

Lawrence T Lam

2008-01-01

332

Subliminal strengthening: improving older individuals' physical function over time with an implicit-age-stereotype intervention.  

PubMed

Negative age stereotypes that older individuals assimilate from their culture predict detrimental outcomes, including worse physical function. We examined, for the first time, whether positive age stereotypes, presented subliminally across multiple sessions in the community, would lead to improved outcomes. Each of 100 older individuals (age = 61-99 years, M = 81) was randomly assigned to an implicit-positive-age-stereotype-intervention group, an explicit-positive-age-stereotype-intervention group, a combined implicit- and explicit-positive-age-stereotype-intervention group, or a control group. Interventions occurred at four 1-week intervals. The implicit intervention strengthened positive age stereotypes, which strengthened positive self-perceptions of aging, which, in turn, improved physical function. The improvement in these outcomes continued for 3 weeks after the last intervention session. Further, negative age stereotypes and negative self-perceptions of aging were weakened. For all outcomes, the implicit intervention's impact was greater than the explicit intervention's impact. The physical-function effect of the implicit intervention surpassed a previous study's 6-month-exercise-intervention's effect with participants of similar ages. The current study's findings demonstrate the potential of directing implicit processes toward physical-function enhancement over time. PMID:25326508

Levy, Becca R; Pilver, Corey; Chung, Pil H; Slade, Martin D

2014-12-01

333

American Council on Exercise  

NSDL National Science Digital Library

Founded in 1985, the American Council on Fitness is largely known for operating as a fitness certification and education provider. Fortunately for the average person looking for helpful information about exercise materials, the Council website is a treasure trove of free resources on the subject. Not surprisingly, most of these materials are contained within the "Get Fit!" section of the site. Here visitors will find free exercises, a number of healthy recipes, and discussion boards where they may ask questions of fitness professionals. Another useful area is the Operation FitKids section of the site. This section provides tips of keeping fit especially geared towards young people, along with informational fact sheets. Finally, there are a number of reports (sponsored by the ACE) that investigate various health and fitness practices, such as the best (and worst) abdominal exercises.

334

Locomotor exercise in weightlessness  

NASA Technical Reports Server (NTRS)

The requirements for exercise in space by means of locomotion are established and addressed with prototype treadmills for use during long-duration spaceflight. The adaptation of the human body to microgravity is described in terms of 1-G locomotor biomechanics, the effects of reduced activity, and effective activity-replacement techniques. The treadmill is introduced as a complement to other techniques of force replacement with reference given to the angle required for exercise. A motor-driven unit is proposed that can operate at a variety of controlled speeds and equivalent grades. The treadmills permit locomotor exercise as required for long-duration space travel to sustain locomotor and cardiorespiratory capacity at a level consistent with postflight needs.

Thornton, W.; Whitmore, H.

1991-01-01

335

Anterior cruciate ligament reconstruction using bone plug-free quadriceps tendon autograft: intermediate-term clinical outcome after 24–36 months  

PubMed Central

Introduction Although known as a possible graft option for decades, quadriceps tendon grafts have often been termed a second-line graft option. We report a consecutive case series using this method as the primary treatment line. The rationale for this study was to evaluate the midterm results of this method in a prospective and consecutive case series. The primary study question was to determine the clinical results 24–36 months after primary anterior cruciate ligament (ACL) reconstruction using a bone plug-free quadriceps tendon autograft fixed with bioabsorbable cross-pins. Materials and methods The study population included 55 patients, of whom 24 were female (43.6%). The mean age at the index procedure was 31.7 years (15–58 years). All patients received an ACL construction using a bone block-free quadriceps tendon graft fixed with resorbable cross-pins. The postoperative regimen included partial weight-bearing for 3 weeks and flexion limited to 90° for six weeks; an orthosis was not used. The mean follow-up duration was 29.5 months (24.3–38.5 months) after the index procedure. The International Knee Documentation Committee (IKDC) subjective score and examination form was assessed, as well as the Lysholm and Gillquist score and the Tegner activity index. The Rolimeter arthrometer was used to assess the anterior laxity of the knee. Results Graft harvesting was possible in all cases; a bony extension was never required. On average, graft length was measured at 8.8 cm (7.5–10 cm). The mean IKDC subjective score at follow-up was 80.44 points (55.17–100 points, standard deviation [SD] 12.05). The mean preinjury Tegner activity index was 4.98 (2–7) compared to a mean value of 4.16 (2–7, SD 0.8) at follow-up. There was a mean loss of 0.82 index points. The average Lysholm and Gillquist score was 89 points (65–100, SD 17.7). Of the results, 89.1% were in the good or very good groups; in one case (1.8%), the result was poor, while the rest were fair. Conclusion ACL reconstruction using a bone plug-free quadriceps tendon autograft achieved satisfactory results in a midterm review. PMID:24379730

Schulz, Arndt P; Lange, Vivien; Gille, Justus; Voigt, Christine; Fröhlich, Susanne; Stuhr, Markus; Jürgens, Christian

2013-01-01

336

[Metabolic intolerance to exercise].  

PubMed

Exercise intolerance (EI) is a frequent cause of medical attention, although it is sometimes difficult to come to a final diagnosis. However, there is a group of patients in whom EI is due to a metabolic dysfunction. McArdle's disease (type V glucogenosis) is due to myophosphorylase (MPL) deficiency. The ischemic exercise test shows a flat lactate curve. The most frequent mutations in the PYGM gene (MPL gene) in Spanish patients with MPL deficiency are R49X and W797R. Carnitine palmitoyltransferase (CPT) II deficiency is invariably associated to repetitive episodes of myoglobinuria triggered by exercise, cold, fever or fasting. The diagnosis depends on the demonstration of CPT II deficiency in muscle. The most frequent mutation in the CPT2 gene is the S113L. Patients with muscle adenylate deaminase deficiency usually show either a mild myopathy or no symptom. The diagnosis is based on the absence of enzyme activity in muscle and the lack of rise of ammonia in the forearm ischemic exercise test. The mutation Q12X in the AMPD1 gene is strongly associated with the disease. Exercise intolerance is a common complaint in patients with mitochondrial respiratory chain (MRC) deficiencies, although it is often overshadowed by other symptoms and signs. Only recently we have come to appreciate that exercise intolerance can be the sole presentation of defects in the mtDNA, particularly in complex I, complex III, complex IV, or in some tRNAs. In addition, myoglobinuria can be observed in patients under statin treatment, particularly if associated with fibrates, due to an alteration in the assembly of the complex IV of the MRC. PMID:12838448

Arenas, J; Martín, M A

2003-01-01

337

Exercises in Math Readiness  

NSDL National Science Digital Library

Arriving at college, many individuals may find themselves in the need of some instructional tools to refresh their memories on various mathematical concepts. Fortunately for those individuals (and their teachers), the Exercises in Math Readiness website contains materials that will ease this process. Created by the Department of Mathematics and Statistics at the University of Saskatchewan, the site contains exercises of varying difficulty that will take users through such topics as geometry, trigonometry, algebra, and exponential functions. Teachers will also want to look at the section that offers them some specific instructions on how the site might best be used with students. Additionally, the materials here are available in French, Georgian, and Russian.

Rempel, Stephan

338

Mineral Classification Exercise  

NSDL National Science Digital Library

This exercise is designed to help students think about the properties of minerals that are most useful for mineral classification and identification. Students are given a set of minerals and asked to come up with a hierarchical classification scheme (a "key") that can be used to identify different mineral species. They compare their results with the products of other groups. They test the various schemes by applying them to unknown samples. While doing this exercise, the students develop observational and interpretational skill. They also begin to think about the nature of classification systems.

Perkins, Dexter

339

Mercenaria Laboratory Exercise  

NSDL National Science Digital Library

This Invertebrate Anatomy Online exercise, featuring the hard-shell clam Mercenaria mercenaria (quahog), is part of an Internet laboratory manual for courses in Invertebrate Zoology. This exercise features an introduction to Mollusca and a step-by-step dissection guide, including hand-drawn figures, defined terms, and detailed explanations of form and function. Students will learn about the external anatomy (shell), muscles, mantle skirts, mantle cavity, mantle folds, siphons, gills, labial palps, hemal system, exhalant chamber, excretory system, digestive system, nervous system, and reproductive system.

Richard Fox

340

Exercise acts as a drug; the pharmacological benefits of exercise  

PubMed Central

The beneficial effects of regular exercise for the promotion of health and cure of diseases have been clearly shown. In this review, we would like to postulate the idea that exercise can be considered as a drug. Exercise causes a myriad of beneficial effects for health, including the promotion of health and lifespan, and these are reviewed in the first section of this paper. Then we deal with the dosing of exercise. As with many drugs, dosing is extremely important to get the beneficial effects of exercise. To this end, the organism adapts to exercise. We review the molecular signalling pathways involved in these adaptations because understanding them is of great importance to be able to prescribe exercise in an appropriate manner. Special attention must be paid to the psychological effects of exercise. These are so powerful that we would like to propose that exercise may be considered as a psychoactive drug. In moderate doses, it causes very pronounced relaxing effects on the majority of the population, but some persons may even become addicted to exercise. Finally, there may be some contraindications to exercise that arise when people are severely ill, and these are described in the final section of the review. Our general conclusion is that exercise is so effective that it should be considered as a drug, but that more attention should be paid to the dosing and to individual variations between patients. PMID:22486393

Vina, J; Sanchis-Gomar, F; Martinez-Bello, V; Gomez-Cabrera, MC

2012-01-01

341

Electrical Stimulation Versus Electromyographic Biofeedback in the Recovery of Quadriceps Femoris Muscle Function Following Anterior Cruciate Ligament Surgery  

Microsoft Academic Search

Both electrical stimulation and electromyographic bibjeedback hat~e been shown to be more emtive than voluntary isometric exercise alone in the recovery of quadri- ceps fernoris muscle force following anterior cmiate ligament (ACL) recomtmc- tion. In a compa&n of these two modalities, 30 patients with ACL reconstmction were randomly mgned to either a group receiving electrical stimulation in con- jurution with

Vanessa Draper; Lori Ballard

342

Exercise for Your Bone Health  

MedlinePLUS

... supported by your browser. Home Bone Basics Lifestyle Exercise for Your Bone Health Publication available in: PDF ( ... ??) Related Resources Alcoholism Bed Rest and Immobilization Exercise and Osteogenesis Imperfecta Overtraining Risks for Women Oral ...

343

Strengthening of defected beam–column joints using CFRP  

PubMed Central

This paper presents an experimental study for the structural performance of reinforced concrete (RC) exterior beam–column joints rehabilitated using carbon-fiber-reinforced polymer (CFRP). The present experimental program consists of testing 10 half-scale specimens divided into three groups covering three possible defects in addition to an adequately detailed control specimen. The considered defects include the absence of the transverse reinforcement within the joint core, insufficient bond length for the beam main reinforcement and inadequate spliced implanted column on the joint. Three different strengthening schemes were used to rehabilitate the defected beam–column joints including externally bonded CFRP strips and sheets in addition to near surface mounted (NSM) CFRP strips. The failure criteria including ultimate capacity, mode of failure, initial stiffness, ductility and the developed ultimate strain in the reinforcing steel and CFRP were considered and compared for each group for the control and the CFRP-strengthened specimens. The test results showed that the proposed CFRP strengthening configurations represented the best choice for strengthening the first two defects from the viewpoint of the studied failure criteria. On the other hand, the results of the third group showed that strengthening the joint using NSM strip technique enabled the specimen to outperform the structural performance of the control specimen while strengthening the joints using externally bonded CFRP strips and sheets failed to restore the strengthened joints capacity.

Mahmoud, Mohamed H.; Afefy, Hamdy M.; Kassem, Nesreen M.; Fawzy, Tarek M.

2013-01-01

344

The Intensive Diet and Exercise for Arthritis (IDEA) trial: design and rationale  

PubMed Central

Background Obesity is the most modifiable risk factor, and dietary induced weight loss potentially the best nonpharmacologic intervention to prevent or to slow osteoarthritis (OA) disease progression. We are currently conducting a study to test the hypothesis that intensive weight loss will reduce inflammation and joint loads sufficiently to alter disease progression, either with or without exercise. This article describes the intervention, the empirical evidence to support it, and test-retest reliability data. Methods/Design This is a prospective, single-blind, randomized controlled trial. The study population consists of 450 overweight and obese (BMI = 27–40.5 kg/m2) older (age ? 55 yrs) adults with tibiofemoral osteoarthritis. Participants are randomized to one of three 18-month interventions: intensive dietary restriction-plus-exercise; exercise-only; or intensive dietary restriction-only. The primary aims are to compare the effects of these interventions on inflammatory biomarkers and knee joint loads. Secondary aims will examine the effects of these interventions on function, pain, and mobility; the dose response to weight loss on disease progression; if inflammatory biomarkers and knee joint loads are mediators of the interventions; and the association between quadriceps strength and disease progression. Results Test-retest reliability results indicated that the ICCs for knee joint load variables were excellent, ranging from 0.86 – 0.98. Knee flexion/extension moments were most affected by BMI, with lower reliability with the highest tertile of BMI. The reliability of the semi-quantitative scoring of the knee joint using MRI exceeded previously reported results, ranging from a low of 0.66 for synovitis to a high of 0.99 for bone marrow lesion size. Discussion The IDEA trial has the potential to enhance our understanding of the OA disease process, refine weight loss and exercise recommendations in this prevalent disease, and reduce the burden of disability. Trial Registration NCT00381290 PMID:19638215

Messier, Stephen P; Legault, Claudine; Mihalko, Shannon; Miller, Gary D; Loeser, Richard F; DeVita, Paul; Lyles, Mary; Eckstein, Felix; Hunter, David J; Williamson, Jeff D; Nicklas, Barbara J

2009-01-01

345

Dynamic inter-limb resistance exercise device for long-duration space flight  

NASA Technical Reports Server (NTRS)

Essential for fitness on Earth, resistive exercise is even more important for astronauts, who must maintain muscle and bone strength in the absence of gravity. To meet this need, designers and scientists at NASA Ames Research Center, Life Science Division, have worked to develop more effective exercise devices for long-duration exposure to microgravity. One of these concepts is the Inter-Limb Resistance Device which allows the subject to exercise one limb directly against another, strengthening muscle groups in the arms, legs, and back. It features a modular harness with an inelastic cable and instrumented pulley. Forces similar to other high resistance exercise equipment are generated. Sensors in the pulley measure force and velocity for performance feedback display and data acquisition. This free-floating apparatus avoids vibration of sensitive experiments on board spacecraft. Compact with low mass, this hardware is also well suited for a 'safe haven' from radiation on board Space Station Freedom, and may prove useful in confined environments on Earth, such as Antarctic stations, submarines, and other underwater habitats. Potential spin-offs of this technology include products for personal strengthening and cardiovascular conditioning, rehabilitation of hospital patients, fitness exercise for the disabled, and retraining after sports injuries.

Schwandt, Douglas F.; Watenpaugh, Donald E.; Parazynski, Scott E.; Hargens, Alan R.

1991-01-01

346

VOCATIONAL TALENT EXERCISES, PART D.  

ERIC Educational Resources Information Center

THIS WORKBOOK WAS DEVELOPED IN A CURRICULUM PROJECT, DESCRIBED IN VT 004 454, TO HELP YOUNG PEOPLE LEARN BASIC PRINCIPLES AND CONCEPTS OF MECHANICS AND TECHNOLOGY BY MEANS OF A SERIES OF APTITUDE TRAINING EXERCISES. IT IS THE LAST OF FOUR BOOKS WHICH PRESENT 30 EXERCISES DESIGNED FOR 30 CLASS PERIODS. THE EXERCISES ARE SIMILAR TO APTITUDE TEST…

George Washington Univ., Washington, DC. School of Education.

347

Sport Studies (Exercise and Health)  

E-print Network

BSc (Hons) Sport Studies (Exercise and Health) DEGREE PROGRAMME GUIDE 2013-2014 #12;BSc (Hons) Sports Studies (Exercise and Health) Introduction Degree Aims and Outcomes General Enquiries General, sport and exercise acquire increasing importance as foundations for health. The consequence of prolonged

Levi, Ran

348

Exercise and Fluid Balance Update  

ERIC Educational Resources Information Center

One common piece of advice that exercise professionals give their clients is to drink water before, during, and after exercise. During exercise people can lose as much as three liters of water per hour (about 100 ounces) through sweat. Dehydration alters normal sweat patterns, which can lead to an increased core body temperature. Since most of the…

Schlicht, Jeff

2005-01-01

349

Hydration during exercise  

Microsoft Academic Search

Summary  Five young unacclimatised subjects were exposed for 4 h at 34 C (10 C dew-point temperature and 0.6 m · s–1 air velocity), while exercising on a bicycle ergometer: 25 min work — 5 min rest cycles for 2 hours followed by 20 min work — 10 min rest cycles for two further hours. 5 experimental sessions were carried out:

V. Candas; J. P. Libert; G. Brandenberger; J. C. Sagot; C. Amoros; J. M. Kahn

1986-01-01

350

Graphic Correlation Exercise  

NSDL National Science Digital Library

This is a graphic correlation lab exercise. It uses real data from a peer-reviewed journal publication by Lucy Edwards (1989). (I have manipulated the data set a little bit.) Students can finish the activity in two hours or less.

Dan Stephen

351

LONGPRO Stream Modeling Exercise  

NSDL National Science Digital Library

The purpose of this exercise is to integrate modeling with field data. The activity includes links to a "virtual field trip" of maps and photographs. Data from a creek is included in the field trip and students use an Excel spreadsheet model to analyze the data.

Bill Locke

352

Slantwise Convection Case Exercise  

NSDL National Science Digital Library

This exercise examines an event that took place in the 24 hour time period beginning at 18Z, Dec 31, 2000 in southern British Columbia, Canada and northern Washington/Idaho, United States. This is a companion piece to the COMET Webcast, Slantwise Convection: An Operational Approach.

COMET

2002-06-17

353

Computer Exercises in Meteorology.  

ERIC Educational Resources Information Center

Beginning with Western Kentucky University's (Bowling Green) fall 1999 semester, exercises required for the geography and meteorology course used computers for learning. This course enrolls about 250 students per year, most of whom choose it to fulfill a general education requirement. Of the 185 geography majors, it is required for those who…

Trapasso, L. Michael; Conner, Glen; Stallins, Keith

354

Diet and Exercise  

MedlinePLUS

... aware of the important role of a healthy diet and exercise plan in healing. Prior to your discharge from the ... you can ask for help in developing a plan that fits your needs, likes and dislikes. Diet After a Transplant After your transplant, you will ...

355

Exercise and Asthma  

MedlinePLUS

... Adult: 18-21 yrs. Healthy Living Nutrition Fitness Sports Oral Health Emotional Wellness Growing Healthy Safety & Prevention Immunizations Chickenpox ... Health Issues > Conditions > Allergies & Asthma > Exercise and Asthma Health Issues ... every child (and adult) with asthma can benefit from sports and physical activity . Also, asthma should not prevent ...

356

Exercising on a budget  

MedlinePLUS

... Buchner DM. The importance of walking to public health. Med Sci Sports Exerc . 2008 Jul;40(7):S512-S518. Mellett, LH and Bousquet, G. Heart-Healthy Exercise. Circulation. 2013; 127: e571-e572. National Heart, Lung, and Blood ... Accessed April ...

357

Exercises in Persuasion.  

ERIC Educational Resources Information Center

The 35 exercises presented in this paper have been designed to simulate real-life experiences involving the process of persuasion and to enhance understanding of the persuasive process. Among the aspects of the persuasive process dealt with are the identification of persuasive events, emotive language, language intensity, source credibility,…

Schenck-Hamlin, William J.; And Others

358

Cyclostratigraphy and astrochronology exercise  

NSDL National Science Digital Library

This hypothetical Miocene exercise is designed to bring together knowledge of marine sedimentology, magnetostratigraphy, cyclostratigraphy, and biostratigraphy to illustrate how climate changes related to Milankovitch orbital forcing can be used to refine the time scale, determine the timing of events, and estimate rates ("astrochronology").

Elrick, Maya

359

Exercise and functional foods  

Microsoft Academic Search

Appropriate nutrition is an essential prerequisite for effective improvement of athletic performance, conditioning, recovery from fatigue after exercise, and avoidance of injury. Nutritional supplements containing carbohydrates, proteins, vitamins, and minerals have been widely used in various sporting fields to provide a boost to the recommended daily allowance. In addition, several natural food components have been found to show physiological effects,

Wataru Aoi; Yuji Naito; Toshikazu Yoshikawa

2006-01-01

360

Development of an indoor rowing machine with manual FES controller for total body exercise in paraplegia.  

PubMed

Concept 2 indoor rowing machine (Concept 2 Inc., USA) was modified for functional electrical stimulation (FES) rowing exercise in paraplegia. A new seating system provides trunk stability and constrains the leg motion to the sagittal plane. A 4-channel electrical stimulator activates the quadriceps and hamstrings in Drive and Recovery phases of the rowing cycle, respectively. Two force-sensing resistors (FSR) on the handle measure the thumb press as the command signal to the electrical stimulator. Optical encoders measure the positions of the seat and handle during rowing. To synchronize the voluntarily controlled upper body movement with the FES controlled leg movement, a novel manual control system was developed. It uses the voluntary thumb presses to control the timing of the stimulation to the paralyzed leg muscles. The manual control system was intuitive and easy to learn and resulted in well-coordinated rowing. Evaluation of the modified rower by paraplegic volunteers showed that it is effective, safe, and affordable exercise alternative for paraplegics. PMID:12503785

Davoodi, Rahman; Andrews, Brian J; Wheeler, Garry D; Lederer, Robert

2002-09-01

361

34 CFR 608.1 - What is the Strengthening Historically Black Colleges and Universities (HBCU) Program?  

Code of Federal Regulations, 2010 CFR

...Strengthening Historically Black Colleges and Universities (HBCU) Program? 608.1 Section...STRENGTHENING HISTORICALLY BLACK COLLEGES AND UNIVERSITIES PROGRAM General § 608.1 What...Strengthening Historically Black Colleges and Universities (HBCU) Program? The...

2010-07-01

362

75 FR 20717 - Federal Housing Administration: Continuation of FHA Reform; Strengthening Risk Management Through...  

Federal Register 2010, 2011, 2012, 2013

...integrity, competence, or fitness to meet the responsibilities...Strengthening Counterparty Risk Management,'' issued September 18...Strengthening Counterparty Risk Management Mortgagee Letter, issued...of strengthening its risk management. Commenters raised...

2010-04-20

363

Fault Zone Strengthening and Tectonic Reactivation (Invited)  

NASA Astrophysics Data System (ADS)

Tectonic reactivation of geologic faults occurs commonly and for a wide range of spatiotemporal scales and rock types. Fault reactivation may involve weakening processes during periods of tectonic inactivity and/or it may represent the slow pace of fault zone restrengthening, such that faults remain weaker than their surroundings for long time scales. The geometric and structural complexity of tectonic fault zones suggests that fault zone maturity and mineralogy, among other variables, may play a role in determining the conditions under which reactivation occurs. Laboratory experiments focused on frictional processes can offer insight on fault reactivation in the brittle crust via evaluation of frictional healing and weakening. Indeed, many such studies have been conducted to evaluate fault healing in the context of the seismic cycle, which requires that faults restrengthen (heal) between earthquakes. Frictional healing, as evidenced by increasing static friction during quasi-stationary contact, is considered the most likely mechanism of interseismic and dynamic fault strengthening, and there is good agreement between laboratory-based friction laws and field observations of fault healing in some cases. Laboratory observations show that the frictional yield stress increases linearly with log time and that the rate of frictional healing varies with shear stress, chemical environment, mineralogy, and temperature. For quartzofeldspathic rocks the healing rate (expressed as a change in friction coefficient per decade change in waiting time, measured in seconds) ranges from 0.01-0.1, depending on temperature. If these rates extend to geologic time scales, they imply that faults will still be weaker, in a Coulomb-Mohr sense, than their surroundings even after >>108 years. That is, if the coefficient of fault friction goes up by 0.05 per decade in time, and if we start at 0.6, then the effective friction coefficient would be ~1.35 after 108 years. This value is below the strength of intact rock assuming typical values of cohesion and internal friction. This is clearly a very simplified view, but if provides a starting point for discussing fault healing and reactivation. In this talk, I draw on results from studies of frictional healing and stick-slip to address the issue of tectonic fault reactivation.

Marone, C.

2009-12-01

364

OXIDE DISPERSION-STRENGTHENED HEAT EXCHANGER TUBING  

SciTech Connect

Oxide dispersion strengthened (ODS) alloys (e.g. the INCOLOY{reg_sign} MA956 alloy) are known for their excellent high temperature properties and are prime candidate materials for the construction of very high temperature heat exchangers that will be used in Vision 21 power plants. The main limitation of these materials is their poor weldability. Commercially available ODS tubing also tends to exhibit relatively poor circumferential creep strength due to current processing practices resulting in a fine grain size in the transverse direction. Thus far, these two characteristics of the ODS tubing have restricted its use to mostly non-pressure containing applications. The objectives of this program are to develop: (a) an MA956 tube with sufficient circumferential creep strength for long term use as heat exchanger tubing for very high temperatures; (b) a welding technique(s) for producing adequate joints between an MA956 tube and an MA956 tube, and an MA956 tube and an INCONEL 601 tube; (c) the bending strain limits, below which recrystallization will not occur in a MA956 tube during normal operation; and (d) the high temperature corrosion limits for the MA956 alloy with respect to working-fluid side and fireside environments. Also, this program seeks to generate data for use by heat exchanger designers and the ASME Boiler and Pressure Vessel Code, and perform an analysis of the mechanical property, tube bending, and corrosion data in order to determine the implications on the design of a very high temperature heat exchanger (T>1093 C/2000 F). After one year, work is currently being conducted on increasing the circumferential strength of a MA956 tube, developing joining techniques for this material, determining the tube bending strain limits, and establishing the high temperature corrosion parameters for the MA956 alloy in environments expected to be present in Vision 21 power plants. Work in these areas will is continuing into the next fiscal year, with success anticipated to produce innovative developments that will allow the reliable use of ODS alloys for heat exchanger tubing, as well as a variety of applications previously not possible with metallic materials.

Harper, Mark A.

2001-11-06

365

Flexural Strengthening of Steel Bridges with High Modulus CFRP Strips  

E-print Network

of carbon fiber-reinforced poly- mer CFRP materials for repair of fatigue damage Armstrong 1983; Allan et al it avoids field welding, particularly overhead welding, that strengthening with steel requires

366

Can exercise prevent cognitive decline?  

PubMed

As the tolerability of pharmacological agents decreases with age, exercise may be particularly helpful as a possible treatment or stabiliser of mood and cognitive function in older age. Exercise has been most commonly evaluated for the treatment of depression. Exercise interventions designed primarily for treatment of physical conditions in the elderly do appear to confer psychological benefits as well, with reduction in depressive symptoms over the course of treatment. The effects of exercise on reducing depressive symptoms are not dissimilar to the effects of antidepressant drugs and cognitive behaviour therapy. Exercise may be a useful low-tech intervention for people with mild to moderate depression. In particular, exercise may be helpful in the elderly and in patients who have had insufficient response to, or are intolerant of, pharmacotherapy. Mastery of a new skill and positive feedback from others may increase feelings of self-esteem and improve mood. Exercise may distract participants from persistent negative thoughts. Exercise has been shown to improve executive function acutely in adults of all ages. It is possible that dance routines or other exercise regimens requiring some cognitive input may confer additional benefit to cognitive function. Exercise has a moderate effect on the ability of people with dementia to perform activities of daily living and may improve cognitive function. Midlife exercise may also have an impact on later cognitive function. PMID:24617099

Behrman, Sophie; Ebmeier, Klaus P

2014-01-01

367

Electrochemical behavior of sintered oxide dispersion strengthened stainless steels  

Microsoft Academic Search

The electrochemical behavior of powder metallurgy (P\\/M) oxide dispersion strengthened stainless steels (SS) (316L and 434L) have been compared with standard 430 and 316 wrought samples in 0.05 mol\\/l sulfuric acid. The effects of sintering temperature and yttria addition on the electrochemical behavior have been studied. The behaviour of the dispersion strengthened SS was comparable to that of the straight

J Shankar; A Upadhyaya; R Balasubramaniam

2004-01-01

368

Tests of reinforced concrete beams strengthened with wire rope units  

Microsoft Academic Search

This paper presents a simple unbonded-type shear strengthening procedure for reinforced concrete structures with wire rope units. Fifteen beams were tested to failure in shear, repaired, strengthened using the proposed wire rope units, and then retested. The main variables investigated were the shear span-to-depth ratio, and the prestressing force, orientation and spacing of wire rope units. The shear strength of

S. Y. Kim; K. H. Yang; H. Y. Byun; A. F. Ashour

2007-01-01

369

The prediction of precipitation strengthening in microalloyed steels  

Microsoft Academic Search

The effectiveness of interphase precipitation strengthening in microalloyed steels depends on the temperature dependence of\\u000a the solubility of the precipitation phase in austenite and on the temperature utilized in soaking. Using an approximate method\\u000a of calculating the solubility of microalloying elements in the presence of both carbon and nitrogen, a precipitation strengthening\\u000a potential parameter was developed. On relating this parameter

H. R. Lin; A. A. Hendrickson

1988-01-01

370

77 FR 52742 - Public Meeting-Strengthening the National Medical Device Postmarket Surveillance System; Request...  

Federal Register 2010, 2011, 2012, 2013

...Strengthening the National Medical Device Postmarket Surveillance System...Strengthening the National Medical Device Postmarket Surveillance System...public feedback regarding the medical device postmarket surveillance...

2012-08-30

371

?2-adrenergic stimulation enhances Ca2+ release and contractile properties of skeletal muscles, and counteracts exercise-induced reductions in Na+-K+-ATPase Vmax in trained men.  

PubMed

The aim of the present study was to examine the effect of ?2-adrenergic stimulation on skeletal muscle contractile properties, sarcoplasmic reticulum (SR) rates of Ca(2+) release and uptake, and Na(+)-K(+)-ATPase activity before and after fatiguing exercise in trained men. The study consisted of two experiments (EXP1, n = 10 males, EXP2, n = 20 males), where ?2-adrenoceptor agonist (terbutaline) or placebo was randomly administered in double-blinded crossover designs. In EXP1, maximal voluntary isometric contraction (MVC) of m. quadriceps was measured, followed by exercise to fatigue at 120% of maximal oxygen uptake (V?O2, max ). A muscle biopsy was taken after MVC (non-fatigue) and at time of fatigue. In EXP2, contractile properties of m. quadriceps were measured with electrical stimulations before (non-fatigue) and after two fatiguing 45 s sprints. Non-fatigued MVCs were 6 ± 3 and 6 ± 2% higher (P < 0.05) with terbutaline than placebo in EXP1 and EXP2, respectively. Furthermore, peak twitch force was 11 ± 7% higher (P < 0.01) with terbutaline than placebo at non-fatigue. After sprints, MVC declined (P < 0.05) to the same levels with terbutaline as placebo, whereas peak twitch force was lower (P < 0.05) and half-relaxation time was prolonged (P < 0.05) with terbutaline. Rates of SR Ca(2+) release and uptake at 400 nm [Ca(2+)] were 15 ± 5 and 14 ± 5% (P < 0.05) higher, respectively, with terbutaline than placebo at non-fatigue, but declined (P < 0.05) to similar levels at time of fatigue. Na(+)-K(+)-ATPase activity was unaffected by terbutaline compared with placebo at non-fatigue, but terbutaline counteracted exercise-induced reductions in maximum rate of activity (Vmax) at time of fatigue. In conclusion, increased contractile force induced by ?2-adrenergic stimulation is associated with enhanced rate of Ca(2+) release in humans. While ?2-adrenergic stimulation elicits positive inotropic and lusitropic effects on non-fatigued m. quadriceps, these effects are blunted when muscles fatigue. PMID:25344552

Hostrup, M; Kalsen, A; Ortenblad, N; Juel, C; Mørch, K; Rzeppa, S; Karlsson, S; Backer, V; Bangsbo, J

2014-12-15

372

Exercises Including Weight Vests and a Patient Education Program for Women With Osteopenia: A Feasibility Study of the OsteoACTIVE Rehabilitation Program.  

PubMed

Study Design Prospective case series with 1-year follow-up. Objectives The primary aim was to describe the OsteoACTIVE rehabilitation program and evaluate its feasibility in terms of progression, adherence, and adverse events in patients with low bone mineral density (BMD) and a healed forearm fracture. The secondary aim was to assess changes in measures of function and quality of life. Background Previous studies have shown benefits of weight-bearing activities, resistance exercises, and balance and coordination training for women with low BMD and older adults. However, no studies, to our knowledge, have described or examined a rehabilitation program combining the use of weight vests and patient education in patients with low BMD. Methods Forty-two postmenopausal women with osteopenia and a healed forearm fracture attended the OsteoACTIVE program for 6 months (3 sessions of 60 minutes per week). Feasibility was assessed by documenting training progression (load and exercises), program adherence (aiming for greater than 80%), and adverse events (joint pain, muscle soreness, and falls). Secondary measures included quadriceps strength, BMD, dynamic balance, walking ability, and self-report functional outcome measures. All outcome measures were recorded preintervention (baseline), postintervention, and at 1-year follow-up. Results Thirty-five women (83%) completed the 6-month program and 31 women (74%) attended all the follow-up measurement sessions. All participants progressed during the rehabilitation program for both load and type of exercises. Furthermore, 87% of the participants met the a priori goal of 80% adherence, and no participants reported adverse events. Improvements in quadriceps strength and BMD of the femoral trochanter were noted at the end of the 6-month training period (P<.05). At 1-year follow-up, there were significant improvements in quadriceps strength and dynamic balance compared to baseline (P<.05). Conclusion The OsteoACTIVE rehabilitation program was feasible and achieved progression of training level, had high adherence, and had no adverse events. Positive improvements were established in lower extremity function and femoral trochanter BMD. Clinical trial registered at ClinicalTrials.gov (NCT01357278). Level of Evidence Therapy, level 4. J Orthop Sports Phys Ther 2015;45(2):97-105. Epub 10 Jan 2015. doi:10.2519/jospt.2015.4842. PMID:25579693

Hakestad, Kari Anne; Torstveit, Monica Klungland; Nordsletten, Lars; Axelsson, Åsa Christina; Risberg, May Arna

2015-02-01

373

Association of Muscle-strengthening Activity With Knee and Low Back Pain, Falls, and Health-related Quality of Life Among Japanese Older Adults: A Cross-sectional Survey.  

PubMed

This study aimed to examine the association of muscle-strengthening activity with knee and low back pain, falls, and health-related quality of life among Japanese older adults. A cross-sectional survey targeted 3,000 people. The response rate was 52% and 208 respondents did not meet the inclusion criteria. Therefore, 1,351 individuals were analyzed. Muscle-strengthening activity (exercise using equipment and body weight, lifestyle activities), knee and low back pain, falls over the past year, health-related quality of life (SF-8), and potential confounders were assessed. Individuals engaging in exercise using body weight and lifestyle activity (? 2 days/week) were more likely to have knee pain. Engaging in exercise using equipment and body weight was associated with higher scores of general health. These results indicate that exercise using equipment and body weight might have a positive effect on health-related quality of life, but muscle-strengthening activities are associated with knee pain in older people. PMID:24306457

Harada, Kazuhiro; Shibata, Ai; Oka, Koichiro; Nakamura, Yoshio

2015-01-01

374

Bedrock Geology Mapping Exercise  

NSDL National Science Digital Library

This field mapping and map-making exercise is a capstone project for a course on Geological Maps. Over a weekend (~12 hours of field work), students collect lithologic and structural data from outcrops scattered over a one square mile area. Back in the classroom, students digitally compile their field data (outcrop, structure measurements, traverse locations) into ArcMAP. They infer geologic linework (faults and contacts) and units from this data in ArcMAP and then export these data layers into Illustrator. In Illustrator, they add ancillary map components (a cross section, description of map units, correlation diagram, map symbol legend,...) to create a final map at a 1:10,000 scale. Their maps are printed out on 11"x17" paper and saved as a pdf file. This exercise helps the students to appreciate how field data is collected and how these geologic facts are interpretively organized into a four-dimensional picture that is a geologic map.

Miller, Jim

375

[Evidence for exercise prescription].  

PubMed

This brief review includes recent evidences regarding the etiology of obesity and metabolic syndrome with a special reference to autonomic nervous system activity. The role of exercise in prevention and treatment of obesity in adults and children is described in conjunction with MONA LISA Hypothesis put forth by Bray (1991). Finally, recent topics of myokines, i.e., muscle activity-derived cytokines are briefly discussed. PMID:19202914

Moritani, Toshio

2009-02-01

376

Humanoid Assessing Rehabilitative Exercises.  

PubMed

Introduction: This article is part of the Focus Theme of Methods of Information in Medicine on "New Methodologies for Patients Rehabilitation". Background: The article presents the approach in which the rehabilitative exercise prepared by healthcare professional is encoded as formal knowledge and used by humanoid robot to assist patients without involving other care actors. Objectives: The main objective is the use of humanoids in rehabilitative care. An example is pulmonary rehabilitation in COPD patients. Another goal is the automated judgment functionality to determine how the rehabilitation exercise matches the pre-programmed correct sequence. Methods: We use the Aldebaran Robotics' NAO humanoid to set up artificial cognitive application. Pre-programmed NAO induces elderly patient to undertake humanoid-driven rehabilitation exercise, but needs to evaluate the human actions against the correct template. Patient is observed using NAO's eyes. We use the Microsoft Kinect SDK to extract motion path from the humanoid's recorded video. We compare human- and humanoid-operated process sequences by using the Dynamic Time Warping (DTW) and test the prototype. Results: This artificial cognitive software showcases the use of DTW algorithm to enable humanoids to judge in near real-time about the correctness of rehabilitative exercises performed by patients following the robot's indications. Conclusion: One could enable better sustainable rehabilitative care services in remote residential settings by combining intelligent applications piloting humanoids with the DTW pattern matching algorithm applied at run time to compare humanoid- and human-operated process sequences. In turn, it will lower the need of human care. PMID:24986076

Simonov, M; Delconte, G

2014-07-01

377

Exercise and the Elderly  

PubMed Central

By the year 2025, more than 25% of Canadians will be older than 65; and nearly half the population older than 65 has some degree of disability. With physiologic aging comes a gradual loss of functional capacity and independence that becomes a major health burden. Researchers have shown that lifelong, moderate levels of exercise are associated with increased longevity, enhanced physical function, and longer-lasting independent living. PMID:21221294

Taunton, J.; Rhodes, E.; Donnelly, M.; Warren, J.; O'Brien, S.

1992-01-01

378

Effectiveness of phototherapy incorporated into an exercise program for osteoarthritis of the knee: study protocol for a randomized controlled trial  

PubMed Central

Background Osteoarthritis is a chronic disease with a multifactor etiology involving changes in bone alignment, cartilage, and other structures necessary to joint stability. There is a need to investigate therapeutic resources that combine different wavelengths as well as different light sources (low-level laser therapy and light-emitting diode therapy) in the same apparatus for the treatment of osteoarthritis. The aim of the proposed study is to analyze the effect of the incorporation of phototherapy into a therapeutic exercise program for individuals with osteoarthritis of the knee. Methods/Design A double-blind, controlled, randomized clinical trial will be conducted involving patients with osteoarthritis of the knee. Evaluations will be performed using functional questionnaires before and after the treatment protocols, in a reserved room with only the evaluator and participant present, and no time constraints placed on the answers or evaluations. The following functional tests will also be performed: stabilometry (balance assessment), dynamometry (muscle strength of gluteus medius and quadriceps), algometry (pain threshold), fleximeter (range of motion), timed up-and-go test (functional mobility), and the functional reach test. The participants will then be allocated to three groups through a randomization process using opaque envelopes: exercise program, exercise program?+?phototherapy, or exercise program?+?placebo phototherapy, all of which will last for eight weeks. Discussion The purpose of this randomized clinical trial is to analyze the effect of the incorporation of phototherapy into a therapeutic exercise program for osteoarthritis of the knee. The study will support the practice based on evidence to the use of phototherapy in individuals with a diagnosis of osteoarthritis of the knee. Data will be published after the study is completed. Trial registration The protocol for this study has been submitted to Clinical Trials, registration number NCT02102347, on 29 March 2014. PMID:24919587

2014-01-01

379

Addition of synchronous whole-body vibration to body mass resistive exercise causes little or no effects on muscle damage and inflammation.  

PubMed

The purpose of this study was to determine if a moderate intensity whole-body vibration (WBV) body mass resistive exercise session causes additional muscle damage, soreness, and inflammation compared with the same exercise session without vibration (NoV). Ten recreationally active male university students completed 2 separate 24-hour study periods incorporating an exercise session with WBV or NoV. Muscle torque was measured (at 0, 60, and 240°·s-1 angular velocities), soreness (10-point scale) in the upper (UE [triceps]) and lower (LE [quadriceps]) extremities, and muscle inflammation markers (interleukin [IL]-1?, IL-6, IL-10) were measured at 4 time points (preexercise, immediately postexercise, 4 hours post, and 24 hours post). Diet was controlled. Compared with NoV, WBV increased (p < 0.01) muscle soreness at 24 hours postexercise in both the UE (2.2 ± 1.7 vs. 0.6 ± 0.9) and LE (2.0 ± 1.5 vs. 0.7 ± 0.7). Muscle torque was decreased immediately postexercise (p < 0.05) in the UE and LE at 0°·s and in the UE at 240°·s, but there was no difference between exercise treatments. The exercise session caused significant but small increases in IL-1? and IL-6 but with no differences between exercise treatments. Interleukin-10 was increased with WBV (2.9 ± 2.0 to 3.6 ± 1.9 pg·ml-1; p < 0.03). These data suggest that the addition of WBV to exercise has little effect on muscle function and damage, soreness, or inflammation. PMID:23615482

Hazell, Tom J; Olver, T Dylan; Hamilton, Craig D; Lemon, Peter W R

2014-01-01

380

CFRP Mechanical Anchorage for Externally Strengthened RC Beams under Flexure  

NASA Astrophysics Data System (ADS)

De-bonding of carbon fiber reinforced polymers (CFRP) sheets and plates from the concrete substrate is one of the major reasons behind premature failures of beams that are externally strengthened with such CFRP materials. To delay or prevent de-bonding and therefore enhancing the load carrying capacity of strengthened beams, several anchorage systems were developed and used. This paper investigates the use of CFRP mechanical anchorage of CFRP sheets and plates used to externally strengthen reinforced concrete beams under flexure. The pin-and-fan shape CFRP anchor, which is custom-made from typical rolled fiber sheets and bundles of loose fiber is used. Several reinforced concrete beams were casted and tested in standard four-point bending scheme to study the effectiveness of this anchorage system. The beams were externally strengthened in flexure with bonded CFRP sheets and plates and then fastened to the soffit of the beams’ using various patterns of CFRP anchors. It is observed that the CFRP plates begins to separate from the beams as soon as de-bonding occurs in specimens without CFRP anchors, while in beams with CFRP anchors de-bonding was delayed leading to increase in the load carrying capacity over the un-anchored strengthened beams.

Ali, Alnadher; Abdalla, Jamal; Hawileh, Rami; Galal, Khaled

381

Strut Deformation in CFRP-Strengthened Reinforced Concrete Deep Beams  

PubMed Central

Strut-and-tie model (STM) method evolved as one of the most useful designs for shear critical structures and discontinuity regions (D-regions). It provides widespread applications in the design of deep beams as recommended by many codes. The estimation of bottle-shaped strut dimensions, as a main constituent of STM, is essential in design calculations. The application of carbon fibre reinforced polymer (CFRP) as lightweight material with high tensile strength for strengthening D-regions is currently on the increase. However, the CFRP-strengthening of deep beam complicates the dimensions estimation of bottle-shaped strut. Therefore, this research aimed to investigate the effect of CFRP-strengthening on the deformation of RC strut in the design of deep beams. Two groups of specimens comprising six unstrengthened and six CFRP-strengthened RC deep beams with the shear span to the effective depth ratios (a/d) of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00 were constructed in this research. These beams were tested under four-point bending configuration. The deformation of struts was experimentally evaluated using the values of strain along and perpendicular to the strut centreline. The evaluation was made by the comparisons between unstrengthened and CFRP-strengthened struts regarding the widening and shortening. The key variables were a/d ratio and applied load level. PMID:25197698

Panjehpour, Mohammad; Chai, Hwa Kian; Voo, Yen Lei

2014-01-01

382

Strut deformation in CFRP-strengthened reinforced concrete deep beams.  

PubMed

Strut-and-tie model (STM) method evolved as one of the most useful designs for shear critical structures and discontinuity regions (D-regions). It provides widespread applications in the design of deep beams as recommended by many codes. The estimation of bottle-shaped strut dimensions, as a main constituent of STM, is essential in design calculations. The application of carbon fibre reinforced polymer (CFRP) as lightweight material with high tensile strength for strengthening D-regions is currently on the increase. However, the CFRP-strengthening of deep beam complicates the dimensions estimation of bottle-shaped strut. Therefore, this research aimed to investigate the effect of CFRP-strengthening on the deformation of RC strut in the design of deep beams. Two groups of specimens comprising six unstrengthened and six CFRP-strengthened RC deep beams with the shear span to the effective depth ratios (a/d) of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00 were constructed in this research. These beams were tested under four-point bending configuration. The deformation of struts was experimentally evaluated using the values of strain along and perpendicular to the strut centreline. The evaluation was made by the comparisons between unstrengthened and CFRP-strengthened struts regarding the widening and shortening. The key variables were a/d ratio and applied load level. PMID:25197698

Panjehpour, Mohammad; Chai, Hwa Kian; Voo, Yen Lei

2014-01-01

383

Exercise, Eating, Estrogen, and Osteoporosis.  

ERIC Educational Resources Information Center

Osteoporosis affects millions of people, especially women. Three methods for preventing or managing osteoporosis are recommended: (1) exercise; (2) increased calcium intake; and (3) estrogen replacement therapy. (CB)

Brown, Jim

1986-01-01

384

[Muscle enzyme activity and exercise].  

PubMed

Exercise is classically associated with muscular soreness, presenting one to two days later, delayed onset muscular soreness. Blood muscle enzymes and protein elevations are characteristic, and may cause renal failure. Creatin phosphokinase peak appears on the fourth day and depends on exercise type and individual parameters. This effect is attenuated with repeated bouts, by habituation. Metabolic complications are rare. The knowledge of this reaction, even with common exercises, allows to postpone investigations for a complex metabolic disorder, or to avoid stopping a medication for fear of a side effect, as with statins. Indeed, it is necessary to wait for seven days without any exercise before interpreting an elevated CK result. PMID:19180440

Gojanovic, B; Feihl, F; Gremion, G; Waeber, B

2009-02-01

385

Exercise for falls prevention in older people: Assessing the knowledge of exercise science students  

Microsoft Academic Search

Participation in appropriate exercise can help reduce the risk of falls and falls injury in older people. Delivery of population-level exercise interventions requires an expert workforce with skills in development and delivery of group exercise programs and prescription of individually targeted exercise. This study assessed the current knowledge of university exercise science students (as future exercise professionals) across different levels

Daina L. Sturnieks; Caroline F. Finch; Jacqueline C. T. Close; Anne Tiedemann; Stephen R. Lord; Deborah A. Pascoe

2010-01-01

386

Exposure to microgravity for 30 days onboard Bion M1 caused muscle atrophy and decreased regeneration in the mouse femoral Quadriceps  

NASA Astrophysics Data System (ADS)

Mechanical unloading of muscle during spaceflight in microgravity is known to cause muscular atrophy, changes in muscle fiber type composition, gene expression, and reductions in regenerative muscle growth. Although limited data exists for long-term effects of microgravity in human muscle, these processes have mostly been studied in rodents for short periods of time, up to two weeks of spaceflight. Here we report on how 30-day, long-term, mechanical unloading in microgravity affects mouse muscle of the femoral Quadriceps group. To conduct these studies we used muscle tissue from 6 mice from the NASA Biospecimen Sharing Program conducted in collaboration with the Institute for Biomedical Problems of the Russian Academy of Sciences, during the Russian Bion M1 biosatellite mission in 2013. Muscle morphology observed in histological sections shows signs of extensive atrophy and regenerative hypoplasia. Specifically, we observed a two-fold decrease in the number of myonuclei and low density of myofibrils, their separation and fragmentation. Despite obvious atrophy, muscle regeneration nevertheless appears to have continued after 30 days in microgravity as evidenced by thin and short newly formed muscle fibers. Many of them however showed evidence of apoptosis and degradation of synthesized fibrils, suggesting long-term unloading in microgravity affects late stages of myofiber differentiation. Ground asynchronous and vivarium control animals showed normal, well-developed tissue structure with sufficient blood and nerve supply and evidence of regenerative formation of new muscle fibers free of apoptotic nuclei. Myofiber nuclei stress responses in spaceflight animals was detected by positive nuclear immunolocalization of c-jun and c-myc proteins. Regenerative activity of satellite cells in muscle was localized with pax-7, MyoD and MCad immunostaining, and did not appear altered in microgravity. In summary, long-term spaceflight in microgravity causes significant atrophy and degeneration of the femoral Quadriceps muscle group, and it may interfere with muscle regenerative processes by inducing apoptosis in newly formed myofibers during their differentiation phase.

Grigoryan, Eleonora; Radugina, Elena A.; Almeida, Eduardo; Blaber, Elizabeth; Poplinskaya, Valentina; Markitantova, Yulia

387

Resistive Exercise Device  

NASA Technical Reports Server (NTRS)

An exercise device 10 is particularly well suited for use in low gravity environments, and includes a frame 12 with plurality of resistance elements 30,82 supported in parallel on the frame. A load transfer member 20 is moveable relative to the frame for transferring the applied force to the free end of each captured resistance element. Load selection template 14 is removably secured both to the load transfer member, and a plurality of capture mechanisms engage the free end of corresponding resistance elements. The force applying mechanism 53 may be a handle, harness or other user interface for applying a force to move the load transfer member.

Smith, Damon C. (Inventor)

2005-01-01

388

Social Inequality: Computer Exercise  

NSDL National Science Digital Library

This activity is used in an Introduction to Sociology class for undergraduate students. This activity looks at inequality in the United States. This activity uses nine customized datasets on the DataCounts! website to aid students in writing about inequality using data. It guides students through data manipulation using WebCHIP software found at DataCounts!. To open WebCHIP with the dataset for the activity, please see instructions and links in the exercise documents under teaching materials. For more information on how to use WebCHIP, see the How To section on DataCounts!

Raymond D'Angelo

389

Alberta Clipper Case Exercise  

NSDL National Science Digital Library

The COMET Program is pleased to announce the publication of the Alberta Clipper Case Exercise module. This one and half- to 2-hour case study focuses on a snow and blowing snow event in the Canadian prairies and US northern high plains on 11-13 November 2003. The key aim of this module is to step through the forecast process during an Alberta Clipper event from the perspective of a forecaster with the Meteorological Service of Canada. This involves consideration of various observations and model guidance, identification of potential areas of snowfall and blowing snow, nowcasting snowfall development and termination, and considering and providing nowcast updates throughout.

2010-01-01

390

Carbon Dioxide Exercise  

NSDL National Science Digital Library

In this activity, students work in groups, plotting carbon dioxide concentrations over time on overheads and estimating the rate of change over five years. Stacked together, the overheads for the whole class show an increase on carbon dioxide over five years and annual variation driven by photosynthesis. This exercise enables students to practice basic quantitative skills and understand how important sampling intervals can be when studying changes over time. A goal is to see how small sample size may give incomplete picture of data.

Richardson, Randy; Collection, Serc -.

391

High temperature dispersion strengthening of NiAl  

NASA Technical Reports Server (NTRS)

A potential high temperature strengthening mechanism for alloys based on the intermetallic compound NiAl was investigated. This study forms part of an overall program at NASA Lewis Research Center for exploring the potential of alloys based on NiAl for high temperature applications. An alloy containing 2.26 at% Nb and produced by hot extrusion of blended powders was examined in detail using optical and electron microscopy. Interdiffusion between the blended Nb and NiAl powders results in the formation of intermediate phases. A fine dispersion of precipitates of a hexagonal, ordered NiAlNb phases in a matrix of NiAl can be produced and this results in strengthening of the alloy by interfering with dislocation motion at high temperature. These precipitates are, however, found to coarsen during the high temperature (1300 K) deformation at slow strain rates and this may impose some limitatioins on the use of this strengthening mechanism.

Sherman, M.; Vedula, K.

1986-01-01

392

Seismic Strengthening of Carpentry Joints in Traditional Timber Structures  

SciTech Connect

The static and dynamic behavior of timber structures largely depends on their connections. In traditional timber construction, elements are usually connected with carpentry joints based on contact pressure and friction, often with only minor reinforcement generically intended to avoid disassembling. In current practice, interventions for the upgrading of carpentry joints are mainly based on empirical knowledge according to tradition. Often they produce a general strengthening of the connection, but are not specific for the case of seismic action. Strengthening on heuristic bases may be only partially effective or possibly disproportioned. The behavior of the carpentry joints most used in roof structures is examined. The birdsmouth joint, connecting rafters to the tie beam, has been studied first, characterizing its behavior numerically and experimentally in monotonic and cyclic conditions. Other forms of the rafter-to-tie connection, the double notch joint and the case of parallel rafters, are discussed. Some general criteria for the seismic strengthening of these joints are presented.

Parisi, Maria A.; Cordie, Cinzia [Politecnico di Milano, piazza Leonardo da Vinci 32, 20133 Milano (Italy); Piazza, Maurizio [Universita degli studi di Trento, via Mesiano 77, 38050 Trento (Italy)

2008-07-08

393

Spill exercise 1980: an LLNL emergency training exercise  

SciTech Connect

An emergency training exercise at Lawrence Livermore National Laboratory (LLNL) demonstrated that off-hours emergency personnel can respond promptly and effecively to an emergency situation involving radiation, hazardous chemicals, and injured persons. The exercise simulated an explosion in a chemistry laboratory and a subsequent toxic-gas release.

Morse, J.L.; Gibson, T.A.; Vance, W.F.

1981-04-01

394

Effects of a home exercise programme on shoulder pain and functional status in construction workers  

PubMed Central

Background: Repetitive or sustained elevated shoulder postures have been identified as a significant risk factor for occupationally related shoulder musculoskeletal disorders. Construction workers exposed to routine overhead work have high rates of shoulder pain that frequently progresses to functional loss and disability. Exercise interventions have potential for slowing this progression. Aims: To evaluate a therapeutic exercise programme intended to reduce pain and improve shoulder function. Methods: Construction worker volunteers were screened by history and clinical examination to test for inclusion/exclusion criteria consistent with shoulder pain and impingement syndrome. Sixty seven male symptomatic workers (mean age 49) were randomised into a treatment intervention group (n = 34) and a control group (n = 33); asymptomatic subjects (n = 25) participated as an additional control group. Subjects in the intervention group were instructed in a standardised eight week home exercise programme of five shoulder stretching and strengthening exercises. Subjects in the control groups received no intervention. Subjects returned after 8–12 weeks for follow up testing. Results: The intervention group showed significantly greater improvements in the Shoulder Rating Questionnaire (SRQ) score and shoulder satisfaction score than the control groups. Average post-test SRQ scores for the exercise group remained below levels for asymptomatic workers. Intervention subjects also reported significantly greater reductions in pain and disability than controls. Conclusions: Results suggest a home exercise programme can be effective in reducing symptoms and improving function in construction workers with shoulder pain. PMID:14573714

Ludewig, P; Borstad, J

2003-01-01

395

Growth hormone and connective tissue in exercise.  

PubMed

Over the last few years, growth hormone (GH) has become increasingly popular as doping within different sports. However, the precise mechanisms behind the ergogenic (performance enhancing) effects of GH in athletes are still being debated. Besides a well-documented stimulatory effect of GH on carbohydrate and fatty acid metabolism, and a possible anabolic effect on myofibrillar muscle protein, we suggest a role for GH as an anabolic agent in connective tissue in human skeletal muscle and tendon. Given the importance of the connective tissue for the function of skeletal muscle and tendon, a strengthening effect of GH on connective tissue could fit with the ergogenic effect of GH experienced by athletes. This review examines the endogenous secretion of GH and its mediators in relation to exercise. Furthermore, we consider the effect of endogenous GH and administered recombinant human GH (rhGH) on both myofibrillar and connective tissue protein synthesis, thus offering an alternative explanation for the ergogenic effect of GH. Finally, we suggest a possible therapeutic role for rhGH in clinical management of the frequently suffered injuries in the connective tissue. PMID:15998337

Doessing, S; Kjaer, M

2005-08-01

396

Oxide-dispersion strengthening of porous powder metalurgy parts  

DOEpatents

Oxide dispersion strengthening of porous metal articles includes the incorporation of dispersoids of metallic oxides in elemental metal powder particles. Porous metal articles, such as filters, are fabricated using conventional techniques (extrusion, casting, isostatic pressing, etc.) of forming followed by sintering and heat treatments that induce recrystallization and grain growth within powder grains and across the sintered grain contact points. The result is so-called "oxide dispersion strengthening" which imparts, especially, large increases in creep (deformation under constant load) strength to the metal articles.

Judkins, Roddie R. (Knoxville, TN)

2002-01-01

397

Thermogravity system designed for use in dispersion strengthening studies  

NASA Technical Reports Server (NTRS)

A thermogravimetry system designed to study the reduction of oxides in metal and alloy powders to be used in dispersion strengthened materials is described. The apparatus was devised for use at high temperatures with controlled atmospheres. Experimental weight change and moisture evolution results for the thermal decomposition of calcium oxalate monohydrate in dry helium, and experimental weight change results for the reduction of nickel oxide in dry hydrogen and hydrogen containing 15,000 PPM water vapor are presented. The system is currently being successfully applied to the evaluation of the reduction characteristics and the removal of impurities from metals and alloys to be used for dispersion strengthening.

Herbell, T. P.

1972-01-01

398

Exercise Log Date Distance Date Distance  

E-print Network

routine. Are You Starting a New Exercise Program? Stretching Brought to you by Staff Council httpExercise Log Date Distance Date Distance College of Sports Medicine recommends that if you are undertaking an exercise program that you see your

Gering, Jon C.

399

Exercise Concepts for Individuals with Syringomyelia  

MedlinePLUS

Exercise Concepts for Individuals with Syringomyelia Posted on November 6, 2009 by admin by Jim Cavanaugh, PT, ... related duties? 3. Do you have questions about exercise? Do you exercise regularly? Are you involved in ...

400

Exercise-induced leukocyte apoptosis.  

PubMed

Physical exercise is well known to affect leukocyte numbers and function. While regular exercise training has been shown to enhance specific immune functions, acute bouts of intensive exercise often lead to a pro-inflammatory response accompanied by a transient lymphocytopenia and neutrophilia. It can be assumed, that lymphocytopenia can be attributed at least partially to an enhanced lymphocyte apoptosis. In contrast, regulation of neutrophil apoptosis after exercise remains controversial since studies demonstrated both an up-regulation as well as a down-regulation of cell death. However, these discrepancies may be due to differences in exercise protocols, subjects' fitness levels, and to different methodological approaches. Two major signalling pathways of exercise induced apoptosis have been identified. First the external receptor mediated pathway using death receptors, and second the internal, oxidative-mediated pathway which encompasses the mitochondria. Potential apoptosis modulating mediators are reactive oxygen species (ROS), glucocorticoids and cytokines which are part of the systemic inflammatory response evoked after acute intensive exercise. Finally, the physiological impact and clinical relevance of leukocyte apoptosis will be discussed. On the one hand, exercise-induced apoptosis might be a mechanism to remove activated and potentially autoreactive immune cells. On the other hand, apoptosis might be a regulatory mechanism which is necessary for tissue reorganization and adaptational training processes. PMID:24974724

Krüger, Karsten; Mooren, Frank C

2014-01-01

401

Space exercise and Earth benefits.  

PubMed

The detrimental impact of long duration space flight on physiological systems necessitates the development of exercise countermeasures to protect work capabilities in gravity fields of Earth, Moon and Mars. The respective rates of physiological deconditioning for different organ systems during space flight has been described as a result of data collected during and after missions on the Space Shuttle, International Space Station, Mir, and bed rest studies on Earth. An integrated countermeasure that simulates the body's hydrostatic pressure gradient, provides mechanical stress to the bones and muscles, and stimulates the neurovestibular system may be critical for maintaining health and well being of crew during long-duration space travel, such as a mission to Mars. Here we review the results of our studies to date of an integrated exercise countermeasure for space flight, lower body negative pressure (LBNP) treadmill exercise, and potential benefits of its application to athletic training on Earth. Additionally, we review the benefits of Lower Body Positive Pressure (LBPP) exercise for rehabilitation of postoperative patients. Presented first are preliminary data from a 30-day bed rest study evaluating the efficacy of LBNP exercise as an integrated exercise countermeasure for the deconditioning effects of microgravity. Next, we review upright LBNP exercise as a training modality for athletes by evaluating effects on the cardiovascular system and gait mechanics. Finally, LBPP exercise as a rehabilitation device is examined with reference to gait mechanics and safety in two groups of postoperative patients. PMID:16101469

Macias, Brandon R; Groppo, Eli R; Eastlack, Robert K; Watenpaugh, Donald E; Lee, Stuart M C; Schneider, Suzanne M; Boda, Wanda L; Smith, Scott M; Cutuk, Adnan; Pedowitz, Robert A; Meyer, R Scott; Hargens, Alan R

2005-08-01

402

EERRGGOO TTIIPPSS EXERCISE USING STRETCHES  

E-print Network

EEE EERRGGOO TTIIPPSS EXERCISE USING STRETCHES AND POSTURE PROMOTING ACTIVITIES! HOW? Chin Tuck Loose GolferShoulder Roll Side Stretch Back Bend Hand SpreadShoulder Stretch Tennis Elbow Stretch SeeERGO-cisehandoutfordetailsandmoreexercises! #12;ERGO-CISE For Your Body Exercising while working at your computer can help prevent or ease pain

Virginia Tech

403

Exercises Focusing on Nonverbal Communication  

ERIC Educational Resources Information Center

Exercises in nonverbal communication are presented which were designed to be used for experiential learning in cross-cultural training programs. Each exercise is described by goal, number of people, time required, procedure, and discussion. Topics include "first impressions,""eye contact patterns," and "silence." (SW)

Melamed, Lanie; Barndt, Deborah

1977-01-01

404

Mind Maps as Classroom Exercises  

ERIC Educational Resources Information Center

A Mind Map is an outline in which the major categories radiate from a central image and lesser categories are portrayed as branches of larger branches. The author describes an in-class exercise in which small groups of students each create a Mind Map for a specific topic. This exercise is another example of an active and collaborative learning…

Budd, John W.

2004-01-01

405

Non-exercise activity thermogenesis  

Microsoft Academic Search

Abstract—Non-exercise activity thermogenesis,(NEAT) is the energy expenditure of all physical activities other than volitional sporting-like exercise. NEAT includes all the activities that render us vibrant, unique, and independent beings such as working, playing, and dancing. Because people of the same weight have markedly variable activity levels, it is

James A. Levine; Mark W. Vander Weg; James O. Hill; Robert C. Klesges

2003-01-01

406

The Caltech Political Military Exercise.  

ERIC Educational Resources Information Center

The Caltech political military exercise (PME) is a game in which players assume roles of leaders of various countries and attempt to act as they think these leaders would in a time of international crises. The main purposes of the exercise are (1) to provide students with an experience in crisis diplomacy and policy formation, and (2) to provide a…

Munger, E. S.; And Others

407

The influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin and peptide YY in healthy males  

NSDL National Science Digital Library

Resistance (muscle strengthening) exercise is a key component of exercise recommendations for weight control yet very little is known about the effects of resistance exercise on appetite. We investigated the effects of resistance and aerobic exercise on hunger and circulating levels of the gut hormones acylated ghrelin and peptide YY (PYY). Eleven healthy male students: age 21.1 ñ 0.3 y, body mass index 23.1 ñ 0.4 kg/m2, maximum oxygen uptake 62.1 ñ 1.8 mL/kg/min (mean ñ SEM) undertook three, 8-h trials, 1) resistance exercise: a 90 min free weight lifting session followed by a 6.5 h rest period, 2) aerobic exercise: a 60 min run followed by a 7 h rest period, 3) control: an 8 h rest, in a randomised crossover design. Meals were provided 2 and 5 h into each trial. Hunger ratings and plasma concentrations of acylated ghrelin and PYY were measured throughout. Two-way ANOVA revealed significant (P<0.05) interaction effects for hunger, acylated ghrelin and PYY indicating suppressed hunger and acylated ghrelin during aerobic and resistance exercise and increased PYY during aerobic exercise. A significant trial effect was observed for PYY indicating higher concentrations on the aerobic exercise trial than the other trials (8 h area under the curve: control 1411 ñ 110, resistance 1381 ñ 97, aerobic 1750 ñ 170 pg/mL 8 h). These findings suggest ghrelin and PYY may regulate appetite during and after exercise but further research is required to establish whether exercise induced changes in ghrelin and PYY influence subsequent food intake.

David R Broom (Loughborough University); Rachel L Batterham (University college London); James A King (Loughborough University); David J Stensel (Loughborough University)

2008-10-31

408

Respiratory weight losses during exercise.  

NASA Technical Reports Server (NTRS)

Evaporative water loss from the respiratory tract was determined over a wide range of exercise. The absolute humidity of the expired air was the same at all levels of exercise and equal to that measured at rest. The rate of respiratory water loss during exercise was found to be 0.019 of the oxygen uptake times (44 minus water vapor pressure). The rate of weight loss during exercise due to CO2-O2 exchange was calculated. For exercise at oxygen consumption rates exceeding 1.5 L/min in a dry environment with a water vapor pressure of 10 mm Hg, the total rate of weight loss via the respiratory tract is on the order of 2-5 g/min.

Mitchell, J. W.; Nadel, E. R.; Stolwijk, J. A. J.

1972-01-01

409

Do ACE Inhibitors Improve the Response to Exercise Training in Functionally Impaired Older Adults? A Randomized Controlled Trial  

PubMed Central

Background. Loss of muscle mass and strength with ageing is a major cause for falls, disability, and morbidity in older people. Previous studies have found that angiotensin-converting enzyme inhibitors (ACEi) may improve physical function in older people. It is unclear whether ACEi provide additional benefit when added to a standard exercise training program. We examined the effects of ACEi therapy on physical function in older people undergoing exercise training. Methods. Community-dwelling people aged ?65 years with functional impairment were recruited through general (family) practices. All participants received progressive exercise training. Participants were randomized to receive either 4 mg perindopril or matching placebo daily for 20 weeks. The primary outcome was between-group change in 6-minute walk distance from baseline to 20 weeks. Secondary outcomes included changes in Short Physical Performance Battery, handgrip and quadriceps strength, self-reported quality of life using the EQ-5D, and functional impairment measured using the Functional Limitations Profile. Results. A total of 170 participants (n = 86 perindopril, n = 84 placebo) were randomized. Mean age was 75.7 (standard deviation [SD] 6.8) years. Baseline 6-minute walk distance was 306 m (SD 99). Both groups increased their walk distance (by 29.6 m perindopril, 36.4 m placebo group) at 20 weeks, but there was no statistically significant treatment effect between groups (?8.6m [95% confidence interval: ?30.1, 12.9], p = .43). No statistically significant treatment effects were observed between groups for the secondary outcomes. Adverse events leading to withdrawal were few (n = 0 perindopril, n = 4 placebo). Interpretation. ACE inhibitors did not enhance the effect of exercise training on physical function in functionally impaired older people. PMID:24201696

Band, Margaret; Miller, Suzanne; Cvoro, Vera; Witham, Miles; Struthers, Allan; McConnachie, Alex; Lloyd, Suzanne M.; McMurdo, Marion

2014-01-01

410

About the Method of Thermoreactive Electrospark Surface Strengthening  

Microsoft Academic Search

The method of Thermoreactive Electrospark Surface Strengthening (TRESS) is presented in this work. Thus the process of coating formation becomes a less energy consuming one as compared to the basic technology of the electrospark alloying. The additional heat of the chemical reaction of the synthesis final products formation on the substrate contribute to the increase of thickness and continuity of

E. A. Levashov; E. I. Kharlamov; A. E. Kudryashov; A. S. Rogachev; Manshi Ohyanagi; Mitsue Koizumi; Satoru Hosomi

1999-01-01

411

FEA OF THE HORSETAIL CREEK BRIDGE STRENGTHENED WITH FRP LAMINATES  

E-print Network

discrete cracks in ANSYS [4] and occurs as soon as stresses in the concrete exceed the tensile strength beams. #12;In this paper, three-dimensional finite element bridge models using ANSYS software strengthening with FRP laminates. Nonlinear finite element analysis is performed using the ANSYS finite element

Yim, Solomon C.

412

A review on strengthening steel beams using FRP under fatigue.  

PubMed

In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems. PMID:25243221

Kamruzzaman, Mohamed; Jumaat, Mohd Zamin; Sulong, N H Ramli; Islam, A B M Saiful

2014-01-01

413

Strengthening Global Security The central mission of the Laboratory  

E-print Network

, the nation's top-secret program to develop the atomic bomb. Since 1943, the Laboratory has strengthened our security. The Atomic Age Begins The conflict that darkened Europe in the late 1930s at first cast no shadow that derived its power from splitting the atom. HISTORY RESEARCH In the History Gallery The Town That Never Was

414

Strengthening Research by Designing for Coherence and Connections to Practice  

ERIC Educational Resources Information Center

The National Council of Teachers of Mathematics (NCTM) is committed to strengthening relations between research and practice and to the development of a coherent knowledge base that is usable in practice. The need to work toward connection and coherence is not unique to the field of mathematics education. Fields such as medicine, software…

Boerst, Timothy; Confrey, Jere; Heck, Daniel; Knuth, Eric; Lambdin, Diana V.; White, Dorothy; Baltzley, Patricia C.; Quander, Judith Reed

2010-01-01

415

State Council Resolutions on Further Strengthening Rural Education  

ERIC Educational Resources Information Center

Several resolutions on strengthening work in rural education have been made in order to accelerate development of rural education in China, deepen reform of rural education, guarantee a well-off society, and harmonize rural and urban development. This article presents a detailed plan of actions for each resolution. The resolutions are enumerated…

Chinese Education and Society, 2005

2005-01-01

416

Strengthening of concrete structures with FRP sheets and plates  

Microsoft Academic Search

Presents an overview and discusses the applications of fibre reinforced polymer (FRP) sheets and plates in the strengthening of concrete structures. An insight may be obtained from the discussions made to enhance the use of these techniques for productive use. In addition, selected case studies have been furnished where FRP materials have been used for repairing\\/retrofitting, emphasizing the application of

R. V. Balendran; T. M. Rana; A. Nadeem

2001-01-01

417

Modelling the strengthening of glass using epoxy based coatings  

Microsoft Academic Search

Glass strength can be increased by applying epoxy based surface coatings. A number of models have been presented in the literature to explain the strengthening afforded by these coatings but until now there has been no clear evidence to definitively support one model over another. In this work, finite element models (FEM) of four-point bending test specimens have been developed.

Tamer El-Sayed; Russell J. Hand

2011-01-01

418

Annual Report 2011 We strengthen ethical leadership to  

E-print Network

Annual Report 2011 We strengthen ethical leadership to enhance civil society. Rutgers Business - founded 1766 The Institute for Ethical Leadership at Rutgers Business School #12;Message From Our Founders Leadership, we believe leaders need the critical thinking and decision-making skills to create organizations

Lin, Xiaodong

419

Investigating the strengthening of quartz ceramics by hydrothermal treatment  

Microsoft Academic Search

Increasing application of quartz ceramics is accompanied by an increase in the dimensions of the articles, in the complexity of their shapes, a constant increase in demands placed on dimensional accuracy, and also the need to reduce energy expenditure. As a result of all this, extensive use can be found for precision technology in strengthening the components by hydrothermal treatment

S. M. Itkin; V. V. Vikulin

1993-01-01

420

32Connected Talented Innovative Strengthen education and workforce development  

E-print Network

32Connected Talented Innovative Strengthen education and workforce development Educational Talented Innovative33 High School Graduates Higher Education Intent, 2006 100% 83 4% 80% 82.2% 83.4% 61 5 learning and labor exchange organizations including: K-12 Education #12;34Connected Talented Innovative

421

Intergovernmental Approaches for Strengthening K-12 Accountability Systems  

ERIC Educational Resources Information Center

This volume contains an edited transcript of the Rockefeller Institute's October 29, 2007 symposium (Chicago, IL) entitled "Intergovernmental Approaches to Strengthen K-12 Accountability Systems" as well as a framework paper circulated in preparation for the symposium. The transcript begins with a list of the forty state and federal education…

Armour-Garb, Allison, Ed.

2007-01-01

422

A Review on Strengthening Steel Beams Using FRP under Fatigue  

PubMed Central

In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems. PMID:25243221

Jumaat, Mohd Zamin; Ramli Sulong, N. H.

2014-01-01

423

Children's Books in Review: Books on Strengthening Family Ties.  

ERIC Educational Resources Information Center

Reviews children's books that emphasize the strengthening of family ties. Characters in the books realize the importance and influence of family relationships as they struggle with sibling rivalry, self-discovery, peer relationships, a search for heritage, adoption, and death. (SM)

Winfield, Evelyn T.

1991-01-01

424

Optimal Network Security Strengthening Using Attack-Defense Game Model  

Microsoft Academic Search

For assessing the security and optimal strengthening of large enterprise networks, this paper proposes a new a