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Sample records for muscle strength balance

  1. Balance and Muscle Strength in Elderly Women Who Dance Samba

    PubMed Central

    Serra, Marcos Maurício; Alonso, Angelica Castilho; Peterson, Mark; Mochizuki, Luis; Greve, Júlia Maria D'Andréa; Garcez-Leme, Luiz Eugênio

    2016-01-01

    Considering the growth of the aging population, and the increasing risk for falls and related morbidity, it is vital to seek efficient, comprehensive, and culturally relevant prevention programs for elderly people to reduce risks for falls. The aim of the present study was to evaluate the postural balance and muscle strength among women participating in the "Wing of Baianas" in the carnival parades. One hundred and ten women, with an average age of 67.4±5.9 years, were divided into two groups: Baianas group—elderly participants of the carnival parades in the “Wing of Baianas”, and a Control group of women who do not dance samba. Assessments included a physical activity questionnaire, isokinetic muscle strength testing for the knee extensors and flexors, and a postural balance assessment completed on a force platform. There were no differences between groups, for postural balance outcomes, during the eyes open condition; however, with eyes closed, there was a significant effect between groups (Baianas vs Control) in all variables. The Baianas group showed less medio-lateral displacement (p < 0.04); and anteroposterior displacement (p < 0.007); larger amplitudes of medio-lateral displacement (p < 0.001); and anteroposterior displacement (p < 0.001); increased mean velocity (p < 0.01); and elliptical area (p < 0.01) There were no differences in the isokinetic peak torque corrected by body weight, total work and flexor/extensor ratio. Participation in the Wing of Baianas is associated with better balance with closed eyes, but there were no differences between dancers and non-dancers for muscle strength. PMID:27906984

  2. Balance and Muscle Strength in Elderly Women Who Dance Samba.

    PubMed

    Serra, Marcos Maurício; Alonso, Angelica Castilho; Peterson, Mark; Mochizuki, Luis; Greve, Júlia Maria D'Andréa; Garcez-Leme, Luiz Eugênio

    2016-01-01

    Considering the growth of the aging population, and the increasing risk for falls and related morbidity, it is vital to seek efficient, comprehensive, and culturally relevant prevention programs for elderly people to reduce risks for falls. The aim of the present study was to evaluate the postural balance and muscle strength among women participating in the "Wing of Baianas" in the carnival parades. One hundred and ten women, with an average age of 67.4±5.9 years, were divided into two groups: Baianas group-elderly participants of the carnival parades in the "Wing of Baianas", and a Control group of women who do not dance samba. Assessments included a physical activity questionnaire, isokinetic muscle strength testing for the knee extensors and flexors, and a postural balance assessment completed on a force platform. There were no differences between groups, for postural balance outcomes, during the eyes open condition; however, with eyes closed, there was a significant effect between groups (Baianas vs Control) in all variables. The Baianas group showed less medio-lateral displacement (p < 0.04); and anteroposterior displacement (p < 0.007); larger amplitudes of medio-lateral displacement (p < 0.001); and anteroposterior displacement (p < 0.001); increased mean velocity (p < 0.01); and elliptical area (p < 0.01) There were no differences in the isokinetic peak torque corrected by body weight, total work and flexor/extensor ratio. Participation in the Wing of Baianas is associated with better balance with closed eyes, but there were no differences between dancers and non-dancers for muscle strength.

  3. Wii balance board exercise improves balance and lower limb muscle strength of overweight young adults.

    PubMed

    Siriphorn, Akkradate; Chamonchant, Dannaovarat

    2015-01-01

    [Purpose] The potential health benefits of the Nintendo Wii balance board exercise have been widely investigated. However, no study has been conducted to examine the benefits of Wii exercise for overweight young adults. The aim of this study was to investigate the effect of exercise performed on a Nintendo Wii balance board on the balance and lower limb muscle strength in overweight young adults. [Subjects and Methods] Within-subject repeated measures analysis was used. Sixteen young adults (aged 21.87±1.13 years, body mass index 24.15 ± 0.50 kg/m(2)) were recruited. All subjects performed an exercise program on a Wii balance board for 8 weeks (30 min/session, twice a week for 8 weeks). A NeuroCom Balance Master and a hand-held dynamometer were used to measure balance performance and lower limb muscle strength. [Results] According to the comparison of pre- and post-intervention measurements, the Wii balance board exercise program significantly improved the limit of stability parameters. There was also a significant increase in strength of four lower-limb muscle groups: the hip flexor, knee flexor, ankle dorsiflexor and ankle plantarflexor. [Conclusion] These findings suggest that a Wii balance board exercise program can be used to improve the balance and lower limb muscle strength of overweight young adults.

  4. Relationship between lower extremity isometric muscle strength and standing balance in patients with multiple sclerosis.

    PubMed

    Citaker, Seyit; Guclu-Gunduz, Arzu; Yazici, Gokhan; Bayraktar, Deniz; Nazliel, Bijen; Irkec, Ceyla

    2013-01-01

    Muscle strength and standing balance decrease in patients with Multiple Sclerosis (MS). The aim of the present study was to investigate the relationship between the lower extremity isometric muscle strength and standing balance in patients with MS. Forty-seven patients with MS and 10 healthy volunteers were included. Neurological disability level was assessed using Expanded Disability Status Scale (EDSS). Isometric strength of seven lower extremity muscles (hip flexor-extensor-abductor-adductor, knee flexor-extensor, and ankle dorsal flexor) was assessed using hand-held dynamometer. Duration of static one-leg standing balance was measured using digital chronometer. Hip flexor-extensor-abductor-adductor, knee flexor-extensor, and ankle dorsal flexor isometric muscle strength, and duration of one-leg standing balance were decreased in patients with MS when compared with controls (p < 0.05). All assessed lower extremity isometric muscle strength and EDSS level was related duration of one-leg standing balance in patients with MS. All assessed lower extremity isometric muscle strength (except ankle dorsal flexor) was related with EDSS. Hip flexor-extensor-abductor-adductor, knee flexor-extensor, and ankle dorsal flexor isometric muscle strength decreases in ambulatory MS patients. Lower extremity muscle weakness and neurological disability level are related with imbalance in MS population. Hip and knee region muscles weakness increases the neurological disability level. For the better balance and decrease neurological disability level whole lower extremity muscle strengthening should be included in rehabilitation programs.

  5. Associations Between Balance and Muscle Strength, Power Performance in Male Youth Athletes of Different Maturity Status.

    PubMed

    Hammami, Raouf; Chaouachi, Anis; Makhlouf, Issam; Granacher, Urs; Behm, David G

    2016-11-01

    Balance, strength and power relationships may contain important information at various maturational stages to determine training priorities. The objective was to examine maturity-specific relationships of static/dynamic balance with strength and power measures in young male athletes. Soccer players (N = 130) aged 10-16 were assessed with the Stork and Y balance (YBT) tests. Strength/power measures included back extensor muscle strength, standing long jump (SLJ), countermovement jump (CMJ), and 3-hop jump tests. Associations between balance with strength/power variables were calculated according to peak-height-velocity (PHV). There were significant medium-large sized correlations between all balance measures with back extensor strength (r = .486-.791) and large associations with power (r = .511-.827). These correlation coefficients were significantly different between pre-PHV and circa PHV as well as pre-PHV and post-PHV with larger associations in the more mature groups. Irrespective of maturity-status, SLJ was the best strength/power predictor with the highest proportion of variance (12-47%) for balance (i.e., Stork eyes opened) and the YBT was the best balance predictor with the highest proportion of variance (43-78%) for all strength/power variables. The associations between balance and muscle strength/power measures in youth athletes that increase with maturity may imply transfer effects from balance to strength/power training and vice versa in youth athletes.

  6. Balance and ankle muscle strength predict spatiotemporal gait parameters in individuals with diabetic peripheral neuropathy.

    PubMed

    Camargo, Marcela R; Barela, José A; Nozabieli, Andréa J L; Mantovani, Alessandra M; Martinelli, Alessandra R; Fregonesi, Cristina E P T

    2015-01-01

    The aims of this study were to evaluate aspects of balance, ankle muscle strength and spatiotemporal gait parameters in individuals with diabetic peripheral neuropathy (DPN) and verify whether deficits in spatiotemporal gait parameters were associated with ankle muscle strength and balance performance. Thirty individuals with DPN and 30 control individuals have participated. Spatiotemporal gait parameters were evaluated by measuring the time to walk a set distance during self-selected and maximal walking speeds. Functional mobility and balance performance were assessed using the Functional Reach and the Time Up and Go tests. Ankle isometric muscle strength was assessed with a handheld digital dynamometer. Analyses of variance were employed to verify possible differences between groups and conditions. Multiple linear regression analysis was employed to uncover possible predictors of gait deficits. Gait spatiotemporal, functional mobility, balance performance and ankle muscle strength were affected in individuals with DPN. The Time Up and Go test performance and ankle muscle isometric strength were associated to spatiotemporal gait changes, especially during maximal walking speed condition. Functional mobility and balance performance are damaged in DPN and balance performance and ankle muscle strength can be used to predict spatiotemporal gait parameters in individuals with DPN. Copyright © 2015 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  7. Association of postural balance and isometric muscle strength in early- and middle-school-age boys.

    PubMed

    Ibrahim, Alaa I; Muaidi, Qassim I; Abdelsalam, Mohammed S; Hawamdeh, Ziad M; Alhusaini, Adel A

    2013-01-01

    The purpose of this study was to evaluate the isometric muscle strength (IMS) and dynamic balance in early- and middle-school-age boys and to assess the strength of association between the dynamic balance scores and 6 different IMS indexes. This is a cross-sectional study of a convenience sample of 94 boys who were 6 to 10 years of age and classified into an early school age (6-8 years) group (n = 50) and a middle school age (8-10 years) group (n = 44). Balance was tested using a Biodex Balance System. Anteroposterior Stability Index, Mediolateral Stability Index, and Overall Stability Index were recorded. IMS of 11 muscle groups was measured with a handheld dynamometer and categorized into 6 different muscle strength indices. The mean (SD) values of anteroposterior, mediolateral, and overall stability indexes observed for all study boys were 1.9 ± 1.0, 1.2 ± 0.7, and 2.5 ± 1.2 respectively. In the middle school age group, strong positive relationships were detected between the overall stability index and trunk, lower limb, anti-gravity, pro-gravity, and total strength indexes (r = -0.86/P < .001, r = -0.91/P < .001, r = -0.88/P < .001, r = -0.83/P < .001, and r = -0.84/P < .001 respectively), while no significant relationship was detected with the upper limb strength index (r = 0.159/P = .303). In the early school age group, moderate positive relationships were detected between the overall stability index and anti-gravity, lower limb, and total strength indexes (r = -0.404/P = .004, r = -0.356/P = .011, and r = -0.350/P = .013 respectively). Dynamic balance did not appear to be mature by the age of 10 years. Better balance skills were recorded in the mediolateral direction than in the anteroposterior direction. In the middle school age group, the overall stability index had positive relationships with almost all examined muscle strength indexes excepting the upper limb strength index. © 2013. Published by National University of Health Sciences All rights

  8. Effects of core instability strength training on trunk muscle strength, spinal mobility, dynamic balance and functional mobility in older adults.

    PubMed

    Granacher, Urs; Lacroix, Andre; Muehlbauer, Thomas; Roettger, Katrin; Gollhofer, Albert

    2013-01-01

    Age-related postural misalignment, balance deficits and strength/power losses are associated with impaired functional mobility and an increased risk of falling in seniors. Core instability strength training (CIT) involves exercises that are challenging for both trunk muscles and postural control and may thus have the potential to induce benefits in trunk muscle strength, spinal mobility and balance performance. The objective was to investigate the effects of CIT on measures of trunk muscle strength, spinal mobility, dynamic balance and functional mobility in seniors. Thirty-two older adults were randomly assigned to an intervention group (INT; n = 16, aged 70.8 ± 4.1 years) that conducted a 9-week progressive CIT or to a control group (n = 16, aged 70.2 ± 4.5 years). Maximal isometric strength of the trunk flexors/extensors/lateral flexors (right, left)/rotators (right, left) as well as of spinal mobility in the sagittal and the coronal plane was measured before and after the intervention program. Dynamic balance (i.e. walking 10 m on an optoelectric walkway, the Functional Reach test) and functional mobility (Timed Up and Go test) were additionally tested. Program compliance was excellent with participants of the INT group completing 92% of the training sessions. Significant group × test interactions were found for the maximal isometric strength of the trunk flexors (34%, p < 0.001), extensors (21%, p < 0.001), lateral flexors (right: 48%, p < 0.001; left: 53%, p < 0.001) and left rotators (42%, p < 0.001) in favor of the INT group. Further, training-related improvements were found for spinal mobility in the sagittal (11%, p < 0.001) and coronal plane (11%, p = 0.06) directions, for stride velocity (9%, p < 0.05), the coefficient of variation in stride velocity (31%, p < 0.05), the Functional Reach test (20%, p < 0.05) and the Timed Up and Go test (4%, p < 0.05) in favor of the INT group. CIT proved to be a feasible exercise program for seniors with a high

  9. Side-alternating vibration training for balance and ankle muscle strength in untrained women.

    PubMed

    Spiliopoulou, Styliani I; Amiridis, Ioannis G; Tsigganos, Georgios; Hatzitaki, Vassilia

    2013-01-01

    Side-alternating vibration (SAV) may help reduce the risk of falling by improving body balance control. Such training has been promoted as a strength-training intervention because it can increase muscle activation through an augmented excitatory input from the muscle spindles. To determine the effect of SAV training on static balance during 3 postural tasks of increasing difficulty and lower limb strength. Randomized controlled clinical trial. Laboratory. A total of 21 healthy women were divided into training (n = 11; age = 43.35 ± 4.12 years, height = 169 ± 6.60 cm, mass = 68.33 ± 11.90 kg) and control (n = 10; age = 42.31 ± 3.73 years, height = 167 ± 4.32 cm, mass = 66.29 ± 10.74 kg) groups. The training group completed a 9-week program during which participants performed 3 sessions per week of ten 15-second isometric contractions with a 30-second active rest of 3 exercises (half-squat, wide-stance squat, 1-legged half-squat) on an SAV plate (acceleration = 0.91-16.3g). The control group did not participate in any form of exercise over the 9-week period. We evaluated isokinetic and isometric strength of the knee extensors and flexors and ankle plantar flexors, dorsiflexors, and evertors. Static balance was assessed using 3 tasks of increasing difficulty (quiet bipedal stance, tandem stance, 1-legged stance). The electromyographic activity of the vastus lateralis, semitendinosus, medial gastrocnemius, tibialis anterior, and peroneus longus was recorded during postural task performance, baseline and pretraining, immediately posttraining, and 15 days posttraining. After training in the training group, ankle muscle strength improved (P = .03), whereas knee muscle strength remained unaltered (P = .13). Improved ankle-evertor strength was observed at all angular velocities (P = .001). Postural sway decreased in both directions but was greater in the mediolateral (P < .001) than anteroposterior (P = .02) direction. The electromyographic activity of the peroneus

  10. Treadmill Training with Virtual Reality Improves Gait, Balance, and Muscle Strength in Children with Cerebral Palsy.

    PubMed

    Cho, Chunhee; Hwang, Wonjeong; Hwang, Sujin; Chung, Yijung

    2016-03-01

    Independent walking is an important goal of clinical and community-based rehabilitation for children with cerebral palsy (CP). Virtual reality-based rehabilitation therapy is effective in motivating children with CP. This study investigated the effects of treadmill training with virtual reality on gait, balance, muscular strength, and gross motor function in children with CP. Eighteen children with spastic CP were randomly divided into the virtual reality treadmill training (VRTT) group (9 subjects, mean age, 10.2 years) and treadmill training (TT) group (9 subjects, mean age, 9.4 years). The groups performed their respective programs as well as conventional physical therapy 3 times/week for 8 weeks. Muscle strength was assessed using a digitalized manual muscle tester. Gross motor function was assessed using the Gross Motor Functional Measure (GMFM). Balance was assessed using the Pediatric Balance Scale (PBS). Gait speed was assessed using the 10-meter walk test (10MWT), and gait endurance was assessed using the 2-minute walk test (2MWT). After training, gait and balance was improved in the VRTT compared to the TT group (P < 0.05). Muscular strength was significantly greater in the VRTT group than the TT group, except for right hamstring strength. The improvements in GMFM (standing) and PBS scores were greater in the VRTT group than the TT group (P < 0.05). Furthermore, the VRTT group showed the higher values of 10MWT and 2MWT compared to the TT group (P < 0.05). In conclusion, VRTT programs are effective for improving gait, balance, muscular strength, and gross motor function in children with CP.

  11. Effects of strength training on muscle strength characteristics, functional capabilities, and balance in middle-aged and older women.

    PubMed

    Holviala, Jarkko H S; Sallinen, Janne M; Kraemer, William J; Alen, Markku J; Häkkinen, Keijo K T

    2006-05-01

    Progressive strength training can lead to substantial increases in maximal strength and mass of trained muscles, even in older women and men, but little information is available about the effects of strength training on functional capabilities and balance. Thus, the effects of 21 weeks of heavy resistance training--including lower loads performed with high movement velocities--twice a week on isometric maximal force (ISOmax) and force-time curve (force produced in 500 milliseconds, F0-500) and dynamic 1 repetition maximum (1RM) strength of the leg extensors, 10-m walking time (10WALK) and dynamic balance test (DYN.D) were investigated in 26 middle-aged (MI; 52.8 +/- 2.4 years) and 22 older women (O; 63.8 +/- 3.8 years). 1RM, ISOmax, and F0-500 increased significantly in MI by 28 +/- 10%, 20 +/- 19%, 31 +/- 34%, and in O by 27 +/- 8%, 20 +/- 16%, 18 +/- 45%, respectively. 10WALK (MI and O, p < 0.001) shortened and DYN.D improved (MI and O, p < 0.001). The present strength-training protocol led to large increases in maximal and explosive strength characteristics of leg extensors and in walking speed, as well to an improvement in the present dynamic balance test performance in both age groups. Although training-induced increase in explosive strength is an important factor for aging women, there are other factors that contribute to improvements in dynamic balance capacity. This study indicates that total body heavy resistance training, including explosive dynamic training, may be applied in rehabilitation or preventive exercise protocols in aging women to improve dynamic balance capabilities.

  12. Effects of whole-body vibration on muscle architecture, muscle strength, and balance in stroke patients: a randomized controlled trial.

    PubMed

    Marín, Pedro J; Ferrero, Cristina M; Menéndez, Héctor; Martín, Juan; Herrero, Azael J

    2013-10-01

    The aim of the present study was to analyze the effects of whole-body vibration on lower limb muscle architecture, muscle strength, and balance in stroke patients during a period of 3 mos. The inclusion criteria were having had ischemic or hemorrhagic stroke at least 6 mos before the study and a National Institutes of Health Stroke Scale score of greater than 1 and less than 20. The patients were randomly divided into two groups: an experimental group (n = 11, six men and five women; age, 62.4 ± 10.7 yrs; height, 1.64 ± 0.07 m; mass, 69.4 ± 12.9 kg) and a sham group (n = 9, five men and four women; age, 64.4 ± 7.6 yrs; height, 1.62 ± 0.07 m; mass, 75.0 ± 15.8 kg). The experimental group received a whole-body vibration treatment, with an increase in frequency, sets, and time per set during 17 sessions. The sham group performed the same exercises as that of the experimental group but was not exposed to vibration. Outcome variables included the muscle architecture (the rectus femoris, the vastus lateralis, and the medial gastrocnemius), the maximal isometric voluntary contraction of the knee extensors, and the Berg Balance Scale. There were no significant differences between the groups on the primary outcomes of lower limb muscle architecture, muscle strength, and balance. It seems that whole-body vibration exercise does not augment the increase in neuromuscular performance and lower limb muscle architecture induced by isometric exercise alone in stroke patients.

  13. Muscle strength, gait, and balance in 20 patients with hip osteoarthritis followed for 2 years after THA

    PubMed Central

    Dalén, Nils; Berg, Hans E

    2010-01-01

    Background Patients with hip osteoarthritis (OA) have muscular weakness, impaired balance, and limp. Deficits in the different limb muscles and their recovery courses are largely unknown, however. We hypothesized that there is persisting muscular weakness in lower limb muscles and an impaired balance and gait 2 years after THA. Patients and methods 20 elderly patients with unilateral OA were assessed before, and 6 and 24 months after surgery for maximal voluntary isometric strength of hip and knee muscles and by gait analysis, postural stability, and clinical scores (HHS, SF-36, EuroQoL). Results Hip muscles showed a remaining 6% weakness compared to the contralateral healthy limb 2 years after THA. Preoperatively and 6 months postoperatively, that deficit was 18% and 12%, respectively. Knee extensors fully recovered a preoperative 27% deficit after 2 years. Gait analysis demonstrated a shorter single stance phase for the OA limb compared to healthy limb preoperatively, that had already recovered at the 6-month follow-up. Balance of two-foot standing showed improvement in both sagittal and lateral sway after operation. All clinical scores improved. Interpretation Muscle strength data demonstrated a slow but full recovery of muscles acting about the knee, but there was still a deficit in hip muscle strength 2 years after THA. Gait and balance recovered after the operation. To accelerate improvement in muscular strength after THA, postoperative training should probably be more intense and target hip abductors. PMID:20367414

  14. Whole-body vibration training improves balance, muscle strength and glycosylated hemoglobin in elderly patients with diabetic neuropathy.

    PubMed

    Lee, Kyoungjin; Lee, Seungwon; Song, Changho

    2013-12-01

    Elderly patients with diabetes and peripheral neuropathy are more likely to experience falls. However, the information available on how such falls can be prevented is scarce. We investigated the effects of whole-body vibration (WBV) combined with a balance exercise program on balance, muscle strength, and glycosylated hemoglobin (HbA1c) in elderly patients with diabetic peripheral neuropathy. Fifty-five elderly patients with diabetic neuropathy were randomly assigned to WBV with balance exercise group, balance exercise (BE) group, and control group. The WBV and BE groups performed the balance exercise program for 60 min per day, 2 times per week, for 6 weeks. Further, the WBV group performed WBV training (up to 3 × 3 min, 3 times per week, for 6 weeks). The control group did not participate in any training. The main outcome measures were assessed at baseline and after 6 weeks of training; namely, we assessed the postural sway and one leg stance (OLS) for static balance; Berg balance scale (BBS), timed up-and-go (TUG) test, and functional reach test (FRT) for dynamic balance; five-times-sit-to-stand (FTSTS) test for muscle strength; and HbA1c for predicting the progression of diabetes. Significant improvements were noted in the static balance, dynamic balance, muscle strength, and HbA1c in the WBV group, compared to the BE and control groups (P < 0.05). Thus, in combination with the balance exercise program, the short-term WBV therapy is beneficial in improving balance, muscle strength and HbA1c, in elderly patients with diabetic neuropathy who are at high risk for suffering falls.

  15. Balance Performance During Perturbed Standing Is Not Associated With Muscle Strength and Power in Young Adults.

    PubMed

    Zemková, Erika; Jeleň, Michal; Kováčiková, Zuzana; Miklovič, Peter; Svoboda, Zdeněk; Janura, Miroslav

    2017-01-01

    The authors investigate the ways in which varied postural responses to translating platform perturbations are associated with the variables of strength and power. Twenty-four physically active and 27 sedentary young adults were exposed to a set of postural perturbations at varied velocities (10 and 20 cm/s) and the respective accelerations (6.4 and 6.9 m/s 2 ), constant distance (6 cm), and 4 directions of platform motion (forward, backward, left-lateral, and right-lateral). They also performed maximum voluntary isometric contraction (MVC) and chair rising/chair jumping tests. The analysis of variance revealed significant interaction effect for peak center of pressure displacement, direction by velocity: F 3,129 = 24.43, p = .002; and direction by acceleration: F 3,129 = 34.18, p = .001. There were no significant correlations between peak center of pressure displacements and peak force and peak rate of force development measured during MVC in either standing (r = .27-57) or sitting positions (r = .12-51) and peak power during chair jumping (r = .47-.59) in all participants. As such, only a small proportion of variance was explained (9-39%, 3-23%, and 23-41%, respectively). In conclusion, interaction effects indicate that the composition of stimuli strongly influences compensatory responses and this effect is more pronounced in sedentary than in physically active young adults. Nevertheless, the dynamic balance is not associated with muscle strength and power in either group.

  16. Pilates: Build Strength in Your Core Muscles

    MedlinePlus

    ... an accessible way to build strength in your core muscles for better posture, balance and flexibility. By ... an accessible way to build strength in your core muscles for better posture, balance and flexibility. If ...

  17. Lower limb muscle strength is associated with poor balance in middle-aged women: linear and nonlinear analyses.

    PubMed

    Wu, F; Callisaya, M; Laslett, L L; Wills, K; Zhou, Y; Jones, G; Winzenberg, T

    2016-07-01

    This was the first study investigating both linear associations between lower limb muscle strength and balance in middle-aged women and the potential for thresholds for the associations. There was strong evidence that even in middle-aged women, poorer LMS was associated with reduced balance. However, no evidence was found for thresholds. Decline in balance begins in middle age, yet, the role of muscle strength in balance is rarely examined in this age group. We aimed to determine the association between lower limb muscle strength (LMS) and balance in middle-aged women and investigate whether cut-points of LMS exist that might identify women at risk of poorer balance. Cross-sectional analysis of 345 women aged 36-57 years was done. Associations between LMS and balance tests (timed up and go (TUG), step test (ST), functional reach test (FRT), and lateral reach test (LRT)) were assessed using linear regression. Nonlinear associations were explored using locally weighted regression smoothing (LOWESS) and potential cut-points identified using nonlinear least-squares estimation. Segmented regression was used to estimate associations above and below the identified cut-points. Weaker LMS was associated with poorer performance on the TUG (β -0.008 (95 % CI: -0.010, -0.005) second/kg), ST (β 0.031 (0.011, 0.051) step/kg), FRT (β 0.071 (0.047, 0.096) cm/kg), and LRT (β 0.028 (0.011, 0.044) cm/kg), independent of confounders. Potential nonlinear associations were evident from LOWESS results; significant cut-points of LMS were identified for all balance tests (29-50 kg). However, excepting ST, cut-points did not persist after excluding potentially influential data points. In middle-aged women, poorer LMS is associated with reduced balance. Therefore, improving muscle strength in middle-age may be a useful strategy to improve balance and reduce falls risk in later life. Middle-aged women with low muscle strength may be an effective target group for future randomized

  18. [Effects of community-based comprehensive fall prevention program on muscle strength, postural balance and fall efficacy in elderly people].

    PubMed

    Bae, Jeongyee; Cho, Seong Il

    2014-12-01

    The purposes of this study was to develop a comprehensive community-based fall prevention program and to test the effects of the program on the muscle strength, postural balance and fall efficacy for elderly people. The design of this study was a nonequivalent control group pretest-posttest design. There were 28 participants in the experimental group and 29 in the control group. The program consisted of balance exercises, elastic resistance exercises and prevention education. The program was provided five times a week for 8 weeks and each session lasted 90 minutes. Data were analyzed using χ²-test, independent t-test and paired t-test using the SPSS program. Muscle strength of the lower extremities, postural balance and fall efficacy scores significantly improved in the experimental group compared to the control group. These results suggest that this program can improve lower extremity muscle strength, postural balance and fall efficacy in elders. Therefore, this program is recommended for use in fall prevention programs for elders living in the community.

  19. A structural equation model of the relationship between muscle strength, balance performance, walking endurance and community integration in stroke survivors

    PubMed Central

    2017-01-01

    Purpose To use structural equation modelling (SEM) to determine (1) the direct and indirect associations of strength of paretic lower limb muscles with the level of community integration, and (2) the direct association of walking endurance and balance performance with the level of community integration in community-dwelling stroke survivors. Materials and methods In this cross-sectional study of 105 stroke survivors, the Subjective Index of Physical and Social Outcome (SIPSO) was used to measure the level of community integration. Lower-limb strength measures included isometric paretic ankle strength and isokinetic paretic knee peak torque. The Berg Balance Scale (BBS) and the 6-minute walk test (6MWT) were used to evaluate balance performance and walking endurance, respectively. Results SEM revealed that the distance walked on the 6MWT had the strongest direct association with the SIPSO score (β = 0.41, p <0.001). An increase of one standard deviation in the 6MWT distance resulted in an increase of 0.41 standard deviations in the SIPSO score. Moreover, dorsiflexion strength (β = 0.18, p = 0.044) and the BBS score (β = 0.21, p = 0.021) had direct associations with the SIPSO score. Conclusions The results of the proposed model suggest that rehabilitation training of community-dwelling stroke survivors could focus on walking endurance, balance performance and dorsiflexor muscle strengthening if the aim is to augment the level of community integration. PMID:29049293

  20. The importance of trunk muscle strength for balance, functional performance, and fall prevention in seniors: a systematic review.

    PubMed

    Granacher, Urs; Gollhofer, Albert; Hortobágyi, Tibor; Kressig, Reto W; Muehlbauer, Thomas

    2013-07-01

    The aging process results in a number of functional (e.g., deficits in balance and strength/power performance), neural (e.g., loss of sensory/motor neurons), muscular (e.g., atrophy of type-II muscle fibers in particular), and bone-related (e.g., osteoporosis) deteriorations. Traditionally, balance and/or lower extremity resistance training were used to mitigate these age-related deficits. However, the effects of resistance training are limited and poorly translate into improvements in balance, functional tasks, activities of daily living, and fall rates. Thus, it is necessary to develop and design new intervention programs that are specifically tailored to counteract age-related weaknesses. Recent studies indicate that measures of trunk muscle strength (TMS) are associated with variables of static/dynamic balance, functional performance, and falls (i.e., occurrence, fear, rate, and/or risk of falls). Further, there is preliminary evidence in the literature that core strength training (CST) and Pilates exercise training (PET) have a positive influence on measures of strength, balance, functional performance, and falls in older adults. The objectives of this systematic literature review are: (a) to report potential associations between TMS/trunk muscle composition and balance, functional performance, and falls in old adults, and (b) to describe and discuss the effects of CST/PET on measures of TMS, balance, functional performance, and falls in seniors. A systematic approach was employed to capture all articles related to TMS/trunk muscle composition, balance, functional performance, and falls in seniors that were identified using the electronic databases PubMed and Web of Science (1972 to February 2013). A systematic approach was used to evaluate the 582 articles identified for initial review. Cross-sectional (i.e., relationship) or longitudinal (i.e., intervention) studies were included if they investigated TMS and an outcome-related measure of balance, functional

  1. Increases in muscle strength and balance using a resistance training program administered via a telecommunications system in older adults.

    PubMed

    Sparrow, David; Gottlieb, Daniel J; Demolles, Deborah; Fielding, Roger A

    2011-11-01

    Resistance training programs have been found to improve muscle strength, physical function, and depressive symptoms in middle-aged and older adults. These programs have typically been provided in clinical facilities, health clubs, and senior centers, which may be inconvenient and/or cost prohibitive for some older adults. The purpose of this study was to investigate the effectiveness of an automated telemedicine intervention that provides real-time guidance and monitoring of resistance training in the home. A randomized clinical trial in 103 middle-aged or older participants. Participants were assigned to use of a theory-driven interactive voice response system designed to promote resistance training (Telephone-Linked Computer-based Long-term Interactive Fitness Trainer; n = 52) or to an attention control (n = 51) for a period of 12 months. Measurements of muscle strength, balance, walk distance, and mood were obtained at baseline, 3, 6, and 12 months. We observed increased strength, improved balance, and fewer depressive symptoms in the intervention group than in the control group. Using generalized estimating equations modeling, group differences were statistically significant for knee flexion strength (p = .035), single-leg stance time (p = .029), and Beck Depression Inventory (p = .030). This computer-based telecommunications exercise intervention led to improvements in participants' strength, balance, and depressive symptoms. Because of their low cost and easy accessibility, computer-based interventions may be a cost-effective way of promoting exercise in the home.

  2. The relationship of strength and muscle balance to shoulder pain and impingement syndrome in elite quadriplegic wheelchair rugby players.

    PubMed

    Miyahara, M; Sleivert, G G; Gerrard, D F

    1998-04-01

    Wheelchair athletes are susceptible to injuries related to overuse of the shoulder, in particular shoulder impingement syndrome. The present study examined the relationship of shoulder pain to demographic details, isokinetic strength and muscle balance in 8 elite quadriplegic rugby players. Demographic data were collected using personal interviews and each subject was clinically examined for signs of impingement syndrome by a physician. In addition each subject underwent bilateral isokinetic strength testing of the shoulder at 60 and 180 deg/s for abduction/adduction and internal/external rotation. A series of step-wise multiple discriminant analysis successfully predicted clinical symptoms from demographic, muscular strength and balance data. In particular, there was a significant deficit in adductor strength and this was related to shoulder pain and wasting of the scapular muscles. This strength deficit may be due to the high level of spinal lesions in the quadriplegic population. The level of spinal lesion may contribute to the aetiology of shoulder pathology in quadriplegia, and differentiate it from that observed in able-bodied athletes who exhibit weak abductors.

  3. The effect of aquatic therapy on postural balance and muscle strength in stroke survivors--a randomized controlled pilot trial.

    PubMed

    Noh, Dong Koog; Lim, Jae-Young; Shin, Hyung-Ik; Paik, Nam-Jong

    2008-01-01

    To evaluate the effect of an aquatic therapy programme designed to increase balance in stroke survivors. A randomized, controlled pilot trial. Rehabilitation department of a university hospital. Ambulatory chronic stroke patients (n = 25):13 in an aquatic therapy group and 12 in a conventional therapy group. The aquatic therapy group participated in a programme consisting of Ai Chi and Halliwick methods, which focused on balance and weight-bearing exercises. The conventional therapy group performed gym exercises. In both groups, the interventions occurred for 1 hour, three times per week, for eight weeks. The primary outcome measures were Berg Balance Scale score and weight-bearing ability, as measured by vertical ground reaction force during four standing tasks (rising from a chair and weight-shifting forward, backward and laterally). Secondary measures were muscle strength and gait. Compared with the conventional therapy group, the aquatic therapy group attained significant improvements in Berg Balance Scale scores, forward and backward weight-bearing abilities of the affected limbs, and knee flexor strength (P < 0.05), with effect sizes of 1.03, 1.14, 0.72 and 1.13 standard deviation units and powers of 75, 81, 70 and 26%, respectively. There were no significant changes in the other measures between the two groups. Postural balance and knee flexor strength were improved after aquatic therapy based on the Halliwick and Ai Chi methods in stroke survivors. Because of limited power and a small population base, further studies with larger sample sizes are required.

  4. Effects of a Supervised versus an Unsupervised Combined Balance and Strength Training Program on Balance and Muscle Power in Healthy Older Adults: A Randomized Controlled Trial.

    PubMed

    Lacroix, André; Kressig, Reto W; Muehlbauer, Thomas; Gschwind, Yves J; Pfenninger, Barbara; Bruegger, Othmar; Granacher, Urs

    2016-01-01

    Losses in lower extremity muscle strength/power, muscle mass and deficits in static and particularly dynamic balance due to aging are associated with impaired functional performance and an increased fall risk. It has been shown that the combination of balance and strength training (BST) mitigates these age-related deficits. However, it is unresolved whether supervised versus unsupervised BST is equally effective in improving muscle power and balance in older adults. This study examined the impact of a 12-week BST program followed by 12 weeks of detraining on measures of balance and muscle power in healthy older adults enrolled in supervised (SUP) or unsupervised (UNSUP) training. Sixty-six older adults (men: 25, women: 41; age 73 ± 4 years) were randomly assigned to a SUP group (2/week supervised training, 1/week unsupervised training; n = 22), an UNSUP group (3/week unsupervised training; n = 22) or a passive control group (CON; n = 22). Static (i.e., Romberg Test) and dynamic (i.e., 10-meter walk test) steady-state, proactive (i.e., Timed Up and Go Test, Functional Reach Test), and reactive balance (e.g., Push and Release Test), as well as lower extremity muscle power (i.e., Chair Stand Test; Stair Ascent and Descent Test) were tested before and after the active training phase as well as after detraining. Adherence rates to training were 92% for SUP and 97% for UNSUP. BST resulted in significant group × time interactions. Post hoc analyses showed, among others, significant training-related improvements for the Romberg Test, stride velocity, Timed Up and Go Test, and Chair Stand Test in favor of the SUP group. Following detraining, significantly enhanced performances (compared to baseline) were still present in 13 variables for the SUP group and in 10 variables for the UNSUP group. Twelve weeks of BST proved to be safe (no training-related injuries) and feasible (high attendance rates of >90%). Deficits of balance and lower extremity muscle power can be

  5. Effects of Muscle Strength and Balance Control on Sit-to-Walk and Turn Durations in the Timed Up and Go Test.

    PubMed

    Chen, Tzurei; Chou, Li-Shan

    2017-12-01

    To examine the association of muscle strength and balance control with the amount of time taken to perform sit-to-walk (STW) or turning components of the Timed Up and Go (TUG) test in older adults. Correlations; multiple regression models. General community. Older adults (N=60) age >70 years recruited from the community. Not applicable. Muscle strength, balance control, and TUG test performance time. Muscle strength was quantified by peak joint moments during the isometric maximal voluntary contraction test for bilateral hip abductors, knee extensors, and ankle plantar flexors. Balance control was assessed with the Berg Balance Scale, Fullerton Advanced Balance Scale, and center of mass and ankle inclination angle derived during the TUG test performance. We found that balance control measures were significantly associated with both STW and turning durations even after controlling for muscle strength and other confounders (STW duration: P<.001, turning duration: P=.001). Adding strength to the regression model was found to significantly improve its prediction of STW duration (F change =5.945, P=.018), but not turning duration (F change =1.03, P=.14). Our findings suggest that poor balance control is an important factor that contributes to longer STW and turning durations on the TUG test. Furthermore, strength has a higher association with STW than turning duration. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  6. Associations of dietary patterns with bone mass, muscle strength and balance in a cohort of Australian middle-aged women.

    PubMed

    Wu, Feitong; Wills, Karen; Laslett, Laura L; Oldenburg, Brian; Jones, Graeme; Winzenberg, Tania

    2017-10-01

    Influences of dietary patterns on musculoskeletal health are poorly understood in middle-aged women. This cross-sectional analysis from a cohort of 347 women (aged 36-57 years) aimed to examine associations between dietary patterns and musculoskeletal health outcomes in middle-aged women. Diet was measured by the Cancer Council of Victoria FFQ. Total body bone mineral content (TB BMC), femoral neck and lumbar spine bone density (dual-energy X-ray absorptiometry), lower limbs muscle strength (LMS) and balance tests (timed up and go test, step test, functional reach test (FRT) and lateral reach test) were also measured. Exploratory factor analysis was used to identify dietary patterns and scores for each pattern generated using factor loadings with absolute values ≥0·20. Associations between food pattern scores and musculoskeletal outcomes were assessed using multivariable linear regression. Three dietary patterns were identified: 'Healthy' (high consumption of a plant-based diet - vegetables, legumes, fruit, tomatoes, nuts, snacks, garlic, whole grains and low intake of high-fat dairy products), 'high protein, high fat' (red meats, poultry, processed meats, potatoes, cruciferous and dark-yellow vegetables, fish, chips, spirits and high-fat dairy products) and 'Processed foods' (high intakes of meat pies, hamburgers, beer, sweets, fruit juice, processed meats, snacks, spirits, pizza and low intake of cruciferous vegetables). After adjustment for confounders, Healthy pattern was positively associated with LMS, whereas Processed foods pattern was inversely associated with TB BMC and FRT. The associations were not significant after accounting for multiple comparisons. There were no associations with any other outcomes. These results suggest that maintaining a healthy diet could contribute to bone acquisition, muscle strength and balance in adult life. However, while they provide some support for further investigating dietary strategies for prevention of age

  7. Balance disorder and increased risk of falls in osteoporosis and kyphosis: significance of kyphotic posture and muscle strength.

    PubMed

    Sinaki, Mehrsheed; Brey, Robert H; Hughes, Christine A; Larson, Dirk R; Kaufman, Kenton R

    2005-08-01

    This controlled trial was designed to investigate the influence of osteoporosis-related kyphosis (O-K) on falls. Twelve community-dwelling women with O-K (Cobb angle, 50-65 degrees measured from spine radiographs) and 13 healthy women serving as controls were enrolled. Mean age of the O-K group was 76 years (+/-5.1), height 158 cm (+/-5), and weight 61 kg (+/-7.9), and mean age of the control group was 71 years (+/-4.6), height 161 cm (+/-3.8), and weight 66 kg (+/-11.7). Quantitative isometric strength data were collected. Gait was monitored during unobstructed level walking and during stepping over an obstacle of four different heights randomly assigned (2.5%, 5%, 10%, and 15% of the subject's height). Balance was objectively assessed with computerized dynamic posturography consisting of the sensory organization test. Back extensor strength, grip strength, and all lower extremity muscle groups were significantly weaker in the O-K group than the control group (P <0.05), except right ankle plantar flexors (P =0.09). There was a significant difference in the anteroposterior and mediolateral displacements and velocities. The O-K subjects had less anteroposterior displacement, greater mediolateral displacement, reduced anteroposterior velocity, and increased mediolateral velocity compared with controls for all conditions of unobstructed and obstructed level walking. Obstacle height had a significant effect on all center-of-mass variables. The O-K subjects had significantly greater balance abnormalities on computerized dynamic posturography than the control group (P =0.002). Data show that thoracic hyperkyphosis on a background of reduced muscle strength plays an important role in increasing body sway, gait unsteadiness, and risk of falls in osteoporosis.

  8. The effects of shoulder stabilization exercises and pectoralis minor stretching on balance and maximal shoulder muscle strength of healthy young adults with round shoulder posture.

    PubMed

    Kim, Mi-Kyoung; Lee, Jung Chul; Yoo, Kyung-Tae

    2018-03-01

    [Purpose] The purpose of this study was to analyze the effects of pectoralis minor stretching and shoulder strengthening with an elastic band on balance and maximal shoulder muscle strength in young adults with rounded shoulder posture. [Subjects and Methods] Nineteen subjects with rounded shoulder posture were randomly divided into 2 groups: a shoulder stabilization exercise group and a stretching exercise group. The groups performed each exercise for 40 minutes, 3 times a week, for 4 weeks. Static balance (eyes open and closed), dynamic balance (the limits of stability in 4 directions) and shoulder muscle strength in 5 directions were measure before and after the exercises. [Results] The stretching exercise demonstrated a significant difference between the pre- and post-exercise in the static balance with eyes closed and extension and horizontal abduction strength while the stabilization exercise demonstrated significant difference in the left and right directions between the pre- and post-exercise of the dynamic balance and flexion strength. The stabilization exercise demonstrated significant differences shown in the flexion between the pre- and post-test. [Conclusion] The shoulder stabilization and stretching exercises improved the static balance, dynamic balance, and muscle strength.

  9. Effect of Ankle Range of Motion (ROM) and Lower-Extremity Muscle Strength on Static Balance Control Ability in Young Adults: A Regression Analysis

    PubMed Central

    Kim, Seong-Gil

    2018-01-01

    Background The purpose of this study was to investigate the effect of ankle ROM and lower-extremity muscle strength on static balance control ability in young adults. Material/Methods This study was conducted with 65 young adults, but 10 young adults dropped out during the measurement, so 55 young adults (male: 19, female: 36) completed the study. Postural sway (length and velocity) was measured with eyes open and closed, and ankle ROM (AROM and PROM of dorsiflexion and plantarflexion) and lower-extremity muscle strength (flexor and extensor of hip, knee, and ankle joint) were measured. Pearson correlation coefficient was used to examine the correlation between variables and static balance ability. Simple linear regression analysis and multiple linear regression analysis were used to examine the effect of variables on static balance ability. Results In correlation analysis, plantarflexion ROM (AROM and PROM) and lower-extremity muscle strength (except hip extensor) were significantly correlated with postural sway (p<0.05). In simple correlation analysis, all variables that passed the correlation analysis procedure had significant influence (p<0.05). In multiple linear regression analysis, plantar flexion PROM with eyes open significantly influenced sway length (B=0.681) and sway velocity (B=0.011). Conclusions Lower-extremity muscle strength and ankle plantarflexion ROM influenced static balance control ability, with ankle plantarflexion PROM showing the greatest influence. Therefore, both contractile structures and non-contractile structures should be of interest when considering static balance control ability improvement. PMID:29760375

  10. Effect of Ankle Range of Motion (ROM) and Lower-Extremity Muscle Strength on Static Balance Control Ability in Young Adults: A Regression Analysis.

    PubMed

    Kim, Seong-Gil; Kim, Wan-Soo

    2018-05-15

    BACKGROUND The purpose of this study was to investigate the effect of ankle ROM and lower-extremity muscle strength on static balance control ability in young adults. MATERIAL AND METHODS This study was conducted with 65 young adults, but 10 young adults dropped out during the measurement, so 55 young adults (male: 19, female: 36) completed the study. Postural sway (length and velocity) was measured with eyes open and closed, and ankle ROM (AROM and PROM of dorsiflexion and plantarflexion) and lower-extremity muscle strength (flexor and extensor of hip, knee, and ankle joint) were measured. Pearson correlation coefficient was used to examine the correlation between variables and static balance ability. Simple linear regression analysis and multiple linear regression analysis were used to examine the effect of variables on static balance ability. RESULTS In correlation analysis, plantarflexion ROM (AROM and PROM) and lower-extremity muscle strength (except hip extensor) were significantly correlated with postural sway (p<0.05). In simple correlation analysis, all variables that passed the correlation analysis procedure had significant influence (p<0.05). In multiple linear regression analysis, plantar flexion PROM with eyes open significantly influenced sway length (B=0.681) and sway velocity (B=0.011). CONCLUSIONS Lower-extremity muscle strength and ankle plantarflexion ROM influenced static balance control ability, with ankle plantarflexion PROM showing the greatest influence. Therefore, both contractile structures and non-contractile structures should be of interest when considering static balance control ability improvement.

  11. A New Approach to Improve Cognition, Muscle Strength, and Postural Balance in Community-Dwelling Elderly with a 3-D Virtual Reality Kayak Program.

    PubMed

    Park, Junhyuck; Yim, JongEun

    2016-01-01

    Aging is usually accompanied with deterioration of physical abilities, such as muscular strength, sensory sensitivity, and functional capacity. Recently, intervention methods with virtual reality have been introduced, providing an enjoyable therapy for elderly. The aim of this study was to investigate whether a 3-D virtual reality kayak program could improve the cognitive function, muscle strength, and balance of community-dwelling elderly. Importantly, kayaking involves most of the upper body musculature and needs the balance control. Seventy-two participants were randomly allocated into the kayak program group (n = 36) and the control group (n = 36). The two groups were well matched with respect to general characteristics at baseline. The participants in both groups performed a conventional exercise program for 30 min, and then the 3-D virtual reality kayak program was performed in the kayak program group for 20 min, two times a week for 6 weeks. Cognitive function was measured using the Montreal Cognitive Assessment. Muscle strength was measured using the arm curl and handgrip strength tests. Standing and sitting balance was measured using the Good Balance system. The post-test was performed in the same manner as the pre-test; the overall outcomes such as cognitive function (p < 0.05), muscle strength (p < 0.05), and balance (standing and sitting balance, p < 0.05) were significantly improved in kayak program group compared to the control group. We propose that the 3-D virtual reality kayak program is a promising intervention method for improving the cognitive function, muscle strength, and balance of elderly.

  12. Responsiveness of performance-based outcome measures for mobility, balance, muscle strength and manual dexterity in adults with myotonic dystrophy type 1.

    PubMed

    Kierkegaard, Marie; Petitclerc, Émilie; Hébert, Luc J; Mathieu, Jean; Gagnon, Cynthia

    2018-02-28

    To assess changes and responsiveness in outcome measures of mobility, balance, muscle strength and manual dexterity in adults with myotonic dystrophy type 1. A 9-year longitudinal study conducted with 113 patients. The responsiveness of the Timed Up and Go test, Berg Balance Scale, quantitative muscle testing, grip and pinch-grip strength, and Purdue Pegboard Test was assessed using criterion and construct approaches. Patient-reported perceived changes (worse/stable) in balance, walking, lower-limb weakness, stair-climbing and hand weakness were used as criteria. Predefined hypotheses about expected area under the receiver operating characteristic curves (criterion approach) and correlations between relative changes (construct approach) were explored. The direction and magnitude of median changes in outcome measures corresponded with patient-reported changes. Median changes in the Timed Up and Go test, grip strength, pinch-grip strength and Purdue Pegboard Test did not, in general, exceed known measurement errors. Most criterion (72%) and construct (70%) approach hypotheses were supported. Promising responsiveness was found for outcome measures of mobility, balance and muscle strength. Grip strength and manual dexterity measures showed poorer responsiveness. The performance-based outcome measures captured changes over the 9-year period and responsiveness was promising. Knowledge of measurement errors is needed to interpret the meaning of these longitudinal changes.

  13. Differential Effect of Taekwondo Training on Knee Muscle Strength and Reactive and Static Balance Control in Children with Developmental Coordination Disorder: A Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Fong, Shirley S. M.; Chung, Joanne W. Y.; Chow, Lina P. Y.; Ma, Ada W. W.; Tsang, William W. N.

    2013-01-01

    This randomized controlled trial aimed to investigate the effect of short-term intensive TKD training on the isokinetic knee muscle strength and reactive and static balance control of children with developmental coordination disorder (DCD). Among the 44 children with DCD (mean age: 7.6 plus or minus 1.3 years) recruited, 21 were randomly assigned…

  14. Asymmetry of Muscle Strength in Elite Athletes

    ERIC Educational Resources Information Center

    Drid, Patrik; Drapsin, Miodrag; Trivic, Tatjana; Lukac, Damir; Obadov, Slavko; Milosevic, Zoran

    2009-01-01

    "Study aim": To determine muscle strength variables in elite judoists and wrestlers since thigh muscle strength and bilaterally balanced flexor-to-extensor ratio minimise injury risk and are desirable for achieving sport successes. "Material and methods": Judoists, wrestlers and untrained subjects, 10 each, were subjected to isokinetic strength…

  15. Lower-extremity resistance training on unstable surfaces improves proxies of muscle strength, power and balance in healthy older adults: a randomised control trial.

    PubMed

    Eckardt, Nils

    2016-11-24

    It is well documented that both balance and resistance training have the potential to mitigate intrinsic fall risk factors in older adults. However, knowledge about the effects of simultaneously executed balance and resistance training (i.e., resistance training conducted on unstable surfaces [URT]) on lower-extremity muscle strength, power and balance in older adults is insufficient. The objective of the present study was to compare the effects of machine-based stable resistance training (M-SRT) and two types of URT, i.e., machine-based (M-URT) and free-weight URT (F-URT), on measures of lower-extremity muscle strength, power and balance in older adults. Seventy-five healthy community-dwelling older adults aged 65-80 years, were assigned to three intervention groups: M-SRT, M-URT and F-URT. Over a period of ten weeks, all participants exercised two times per week with each session lasting ~60 min. Tests included assessment of leg muscle strength (e.g., maximal isometric leg extension strength), power (e.g., chair rise test) and balance (e.g., functional reach test), carried out before and after the training period. Furthermore, maximal training load of the squat-movement was assessed during the last training week. Maximal training load of the squat-movement was significantly lower in F-URT in comparison to M-SRT and M-URT. However, lower-extremity resistance training conducted on even and uneven surfaces meaningfully improved proxies of strength, power and balance in all groups. M-URT produced the greatest improvements in leg extension strength and F-URT in the chair rise test and functional reach test. Aside from two interaction effects, overall improvements in measures of lower-extremity muscle strength, power and balance were similar across training groups. Importantly, F-URT produced similar results with considerably lower training load as compared to M-SRT and M-URT. Concluding, F-URT seems an effective and safe alternative training program to mitigate

  16. Increases in muscle strength and balance using a resistance training program administered via a telecommunications system in older adults

    USDA-ARS?s Scientific Manuscript database

    BACKGROUND: Resistance training programs have been found to improve muscle strength, physical function, and depressive symptoms in middle-aged and older adults. These programs have typically been provided in clinical facilities, health clubs, and senior centers, which may be inconvenient and/or cos...

  17. Effects of Supervised vs. Unsupervised Training Programs on Balance and Muscle Strength in Older Adults: A Systematic Review and Meta-Analysis.

    PubMed

    Lacroix, André; Hortobágyi, Tibor; Beurskens, Rainer; Granacher, Urs

    2017-11-01

    Balance and resistance training can improve healthy older adults' balance and muscle strength. Delivering such exercise programs at home without supervision may facilitate participation for older adults because they do not have to leave their homes. To date, no systematic literature analysis has been conducted to determine if supervision affects the effectiveness of these programs to improve healthy older adults' balance and muscle strength/power. The objective of this systematic review and meta-analysis was to quantify the effectiveness of supervised vs. unsupervised balance and/or resistance training programs on measures of balance and muscle strength/power in healthy older adults. In addition, the impact of supervision on training-induced adaptive processes was evaluated in the form of dose-response relationships by analyzing randomized controlled trials that compared supervised with unsupervised trials. A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SportDiscus to detect articles examining the role of supervision in balance and/or resistance training in older adults. The initially identified 6041 articles were systematically screened. Studies were included if they examined balance and/or resistance training in adults aged ≥65 years with no relevant diseases and registered at least one behavioral balance (e.g., time during single leg stance) and/or muscle strength/power outcome (e.g., time for 5-Times-Chair-Rise-Test). Finally, 11 studies were eligible for inclusion in this meta-analysis. Weighted mean standardized mean differences between subjects (SMD bs ) of supervised vs. unsupervised balance/resistance training studies were calculated. The included studies were coded for the following variables: number of participants, sex, age, number and type of interventions, type of balance/strength tests, and change (%) from pre- to post-intervention values. Additionally, we coded training according

  18. Influence of successive badminton matches on muscle strength, power, and body-fluid balance in elite players.

    PubMed

    Abian-Vicen, Javier; Castanedo, Adrián; Abian, Pablo; Gonzalez-Millan, Cristina; Salinero, Juan José; Del Coso, Juan

    2014-07-01

    The aim was to analyze the influence of competitive round on muscle strength, body-fluid balance, and renal function in elite badminton players during a real competition. Body mass, jump height during a countermovement jump, handgrip force, and urine samples were obtained from 13 elite badminton players (6 men and 7 women) before and after the 2nd-round and quarterfinal matches of the national Spanish badminton championship. Sweat rate was determined by using prematch-to-postmatch body-mass change and by weighing individually labeled fluid bottles. Sweat rates were 1.04 ± 0.62 and 0.98 ± 0.43 L/h, while rehydration rate was 0.69 ± 0.26 and 0.91 ± 0.52 L/h for the 2nd round and quarterfinals, respectively. Thus, dehydration was 0.47% ± 1.03% after the 2nd round and 0.23% ± 0.43% after the quarterfinals. There were no differences in prematch-to-postmatch jump height, but jump height was reduced from 37.51 ± 8.83 cm after the 2nd-round game to 34.82 ± 7.37 cm after the quarterfinals (P < .05). No significant differences were found in handgrip force when comparing prepost matches or rounds, although there were significant differences between dominant and nondominant hands (P < .05). The succession of rounds caused the appearance of proteinuria, hematuria, glycosuria, and higher nitrite and ketone concentrations in urine. Rehydration patterns during a real badminton competition were effective to prevent dehydration. A badminton match did not affect jump height or handgrip force, but jump height was progressively reduced by the competitive round. Badminton players' renal responses reflected diminished renal flux due to the high-intensity nature of this racket sport.

  19. The effects of therapeutic exercises on pain, muscle strength, functional capacity, balance and hemodynamic parameters in knee osteoarthritis patients: a randomized controlled study of supervised versus home exercises.

    PubMed

    Kuru Çolak, Tuğba; Kavlak, Bahar; Aydoğdu, Onur; Şahin, Emir; Acar, Gönül; Demirbüken, İlkşan; Sarı, Zübeyir; Çolak, İlker; Bulut, Güven; Polat, M Gülden

    2017-03-01

    The aim of the study was to compare the effects of low-intensity exercise programs for lower extremities, either supervised or at home, on pain, muscle strength, balance and the hemodynamic parameters of knee osteoarthritis (OA) patients. This randomized study included 78 patients with knee OA in 2 groups of supervised and home-based exercise program. Exercises were applied to the first group in the clinic as a group exercise program and were demonstrated to the second group to be performed at home. Before and after the 6-week exercise program, assessment was made of pain, quadriceps and hamstring muscle strengths, 6-min walk test (6MWT), and non-invasive hemodynamic parameters. Results of the 78 patients, 56 completed the study. Pain, muscle strength, and 6MWT scores showed significant improvements in both groups. There were also significant differences in the amount of change in pain and muscle strength (pain: p = 0.041, Rqdc: 0.009, Lqdc: 0.013, Rhms: 0.04) which indicated greater improvements in the supervised group. The balance scores of supervised group showed a significant improvement (p = 0.009). No significant change was determined in hemodynamic parameters of either group. Conclusion according to the results of this study showed that low-intensity lower extremity exercises conducted in a clinic under the supervision of a physiotherapist were more effective than home-based exercises in reducing post-activity pain levels and improving quadriceps and right hamstring muscle strength. Both the supervised and home exercise programs were seen to be effective in reducing rest pain and increasing 6 MW distance in knee osteoarthritis patients.

  20. Associations Between Measures of Balance and Lower-Extremity Muscle Strength/Power in Healthy Individuals Across the Lifespan: A Systematic Review and Meta-Analysis.

    PubMed

    Muehlbauer, Thomas; Gollhofer, Albert; Granacher, Urs

    2015-12-01

    It has frequently been reported that balance and lower-extremity muscle strength/power are associated with sports-related and everyday activities. Knowledge about the relationship between balance, strength, and power are important for the identification of at-risk individuals because deficits in these neuromuscular components are associated with an increased risk of sustaining injuries and falls. In addition, this knowledge is of high relevance for the development of specifically tailored health and skill-related exercise programs. The objectives of this systematic literature review and meta-analysis were to characterize and, if possible, quantify associations between variables of balance and lower-extremity muscle strength/power in healthy individuals across the lifespan. A computerized systematic literature search was performed in the electronic databases PubMed, Web of Science, and SPORTDiscus up to March 2015 to capture all relevant articles. A systematic approach was used to evaluate the 996 articles identified for initial review. Studies were included only if they investigated healthy individuals aged ≥6 years and tested at least one measure of static steady-state balance (e.g., center of pressure [CoP] displacement during one-legged stance), dynamic steady-state balance (e.g., gait speed), proactive balance (e.g., distance in the functional-reach-test), or reactive balance (e.g., CoP displacement during perturbed one-legged stance), and one measure of maximal strength (e.g., maximum voluntary contraction), explosive force (e.g., rate of force development), or muscle power (e.g., jump height). In total, 37 studies met the inclusionary criteria for review. The included studies were coded for the following criteria: age (i.e., children: 6-12 years, adolescents: 13-18 years, young adults: 19-44 years, middle-aged adults: 45-64 years, old adults: ≥65 years), sex (i.e., female, male), and test modality/outcome (i.e., test for the assessment of balance

  1. Influence of Whole-Body Vibration Training Without Visual Feedback on Balance and Lower-Extremity Muscle Strength of the Elderly: A Randomized Controlled Trial.

    PubMed

    Tseng, Shiuan-Yu; Lai, Chung-Liang; Chang, Kai-Ling; Hsu, Pi-Shan; Lee, Meng-Chih; Wang, Chun-Hou

    2016-02-01

    The purpose of this study was to investigate the influence of whole-body vibration (WBV) training without visual feedback on balance and lower-extremity muscle strength in the elderly.Elderly subjects who did not exercise regularly participated in this study. Subjects were randomly divided into a WBV with eyes open group, a visual feedback-deprived plus WBV (VFDWBV) group, and a control group (0 Hz, eyes open). WBV training was provided over a 3-month period, 3 times per week for 5 min each session. Balance performance was measured with the limits of stability test, and muscle strength was measured with an isokinetic dynamometer.A total of 45 elderly subjects with an average age of 69.22  ±  3.97 years, divided into a WBV group (n = 14), a VFDWBV group (n = 17), and a control group (n = 14), completed the trial. Statistically significant differences were found in the balance performance of the 3 groups at different time points (time × group interaction: F = 13.213, P < 0.001), and the VFDWBV group had more improvement in balance than the WBV and control groups. The strength of the knee extensor and flexor muscles had time × group interactions: F = 29.604, P < 0.001 and F = 4.684, P = 0.015, respectively; the VFDWBV group had more improvement on lower-extremity muscle strength than the WBV and control groups. The 6-month follow-up showed that the rates of hospital visits for medical services due to falls were 0% in the WBV group (0/14), 0% in the VFDWBV group (0/17), and 28.57% in the control group (4/14).Results showed that WBV training at 20  Hz without visual feedback can significantly improve the balance performance and lower-extremity muscle strength of the elderly.

  2. Sitting Tai Chi Improves the Balance Control and Muscle Strength of Community-Dwelling Persons with Spinal Cord Injuries: A Pilot Study

    PubMed Central

    Tsang, William W. N.; Gao, Kelly L.; Chan, K. M.; Purves, Sheila; Macfarlane, Duncan J.; Fong, Shirley S. M.

    2015-01-01

    Objective. To investigate the effects of sitting Tai Chi on muscle strength, balance control, and quality of life (QOL) among survivors with spinal cord injuries (SCI). Methods. Eleven SCI survivors participated in the sitting Tai Chi training (90 minutes/session, 2 times/week for 12 weeks) and eight SCI survivors acted as controls. Dynamic sitting balance was evaluated using limits of stability test and a sequential weight shifting test in sitting. Handgrip strength was also tested using a hand-held dynamometer. QOL was measured using the World Health Organization's Quality of Life Scale. Results. Tai Chi practitioners achieved significant improvements in their reaction time (P = 0.042); maximum excursion (P = 0.016); and directional control (P = 0.025) in the limits of stability test after training. In the sequential weight shifting test, they significantly improved their total time to sequentially hit the 12 targets (P = 0.035). Significant improvement in handgrip strength was also found among the Tai Chi practitioners (P = 0.049). However, no significant within and between-group differences were found in the QOL outcomes (P > 0.05). Conclusions. Twelve weeks of sitting Tai Chi training could improve the dynamic sitting balance and handgrip strength, but not QOL, of the SCI survivors. PMID:25688276

  3. Effect of an herbal/botanical supplement on strength, balance, and muscle function following 12-weeks of resistance training: a placebo controlled study

    PubMed Central

    2014-01-01

    Background StemSport (SS; StemTech International, Inc. San Clemente, CA) contains a proprietary blend of the botanical Aphanizomenon flos-aquae and several herbal antioxidant and anti-inflammatory substances. SS has been purported to accelerate tissue repair and restore muscle function following resistance exercise. Here, we examine the effects of SS supplementation on strength adaptations resulting from a 12-week resistance training program in healthy young adults. Methods Twenty-four young adults (16 males, 8 females, mean age = 20.5 ± 1.9 years, mass = 70.9 ± 11.9 kg, stature = 176.6 ± 9.9 cm) completed the twelve week training program. The study design was a double-blind, placebo controlled parallel group trial. Subjects either received placebo or StemSport supplement (SS; mg/day) during the training. 1-RM bench press, 1-RM leg press, vertical jump height, balance (star excursion and center of mass excursion), isokinetic strength (elbow and knee flexion/extension) and perception of recovery were measured at baseline and following the 12-week training intervention. Results Resistance training increased 1-RM strength (p < 0.008), vertical jump height (p < 0.03), and isokinetic strength (p < 0.05) in both SS and placebo groups. No significant group-by-time interactions were observed (all p-values >0.10). Conclusions These data suggest that compared to placebo, the SS herbal/botanical supplement did not enhance training induced adaptations to strength, balance, and muscle function above strength training alone. PMID:24910543

  4. Effect of an herbal/botanical supplement on strength, balance, and muscle function following 12-weeks of resistance training: a placebo controlled study.

    PubMed

    Furlong, Jonathan; Rynders, Corey A; Sutherlin, Mark; Patrie, James; Katch, Frank I; Hertel, Jay; Weltman, Arthur

    2014-01-01

    StemSport (SS; StemTech International, Inc. San Clemente, CA) contains a proprietary blend of the botanical Aphanizomenon flos-aquae and several herbal antioxidant and anti-inflammatory substances. SS has been purported to accelerate tissue repair and restore muscle function following resistance exercise. Here, we examine the effects of SS supplementation on strength adaptations resulting from a 12-week resistance training program in healthy young adults. Twenty-four young adults (16 males, 8 females, mean age = 20.5 ± 1.9 years, mass = 70.9 ± 11.9 kg, stature = 176.6 ± 9.9 cm) completed the twelve week training program. The study design was a double-blind, placebo controlled parallel group trial. Subjects either received placebo or StemSport supplement (SS; mg/day) during the training. 1-RM bench press, 1-RM leg press, vertical jump height, balance (star excursion and center of mass excursion), isokinetic strength (elbow and knee flexion/extension) and perception of recovery were measured at baseline and following the 12-week training intervention. Resistance training increased 1-RM strength (p < 0.008), vertical jump height (p < 0.03), and isokinetic strength (p < 0.05) in both SS and placebo groups. No significant group-by-time interactions were observed (all p-values >0.10). These data suggest that compared to placebo, the SS herbal/botanical supplement did not enhance training induced adaptations to strength, balance, and muscle function above strength training alone.

  5. Analysis of moment structures for assessing relationships among perceived chewing ability, dentition status, muscle strength, and balance in community-dwelling older adults.

    PubMed

    Moriya, Shingo; Notani, Kenji; Murata, Ayumi; Inoue, Nobuo; Miura, Hiroko

    2014-12-01

    The aim of this study was to assess relationships among perceived chewing ability, dentition status, muscle strength and balance in community-dwelling older adults using analysis of moment structures (Amos). Physical performance parameters such as muscle strength and balance can predict the future onset of disabilities in activities of daily living among older adults. In this context, elucidation of the relationships among oral conditions and physical performance parameters is necessary. Data on occlusal contact patterns of natural teeth (OPNT), self-assessed masticatory ability (mastication), body mass index (BMI), handgrip strength (HG) and one-leg standing time with eyes open (OLST) were collected from 501 independently living adults aged 65-74 years. The relationships among these parameters were analysed using Spearman's rank correlation coefficients and Amos. Subjects of both genders showed significant correlations among OPNT, mastication, HG and OLST, evaluated using Spearman's rank correlation coefficients. For each Amos model, the goodness-of-fit statistic indicated a good level of fit. In both men and women, OPNT was significantly related to mastication, and mastication was related to HG but not to OLST. OPNT was related to neither HG nor OLST in women and was related to OLST but not HG in men. The findings observed in this study present a possible importance of dental status and perceived chewing ability for the onset of disability by influencing physical performance in community-dwelling older adults. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

  6. Strength and Balance Exercises

    MedlinePlus

    ... needs and physical condition. If you're at high risk of heart disease , your doctor may conduct an exercise stress test to identify any potential problems. Arm Raise Purpose: Strengthen shoulder muscles. Starting ...

  7. Effects of Pilates on muscle strength, postural balance and quality of life of older adults: a randomized, controlled, clinical trial

    PubMed Central

    Campos de Oliveira, Laís; Gonçalves de Oliveira, Raphael; Pires-Oliveira, Deise Aparecida de Almeida

    2015-01-01

    [Purpose] The aim of the present study was to determine the effects of Pilates on lower leg strength, postural balance and the health-related quality of life (HRQoL) of older adults. [Subjects and Methods] Thirty-two older adults were randomly allocated either to the experimental group (EG, n = 16; mean age, 63.62 ± 1.02 years), which performed two sessions of Pilates per week for 12 weeks, or to the control group (CG, n = 16; mean age, 64.21 ± 0.80), which performed two sessions of static stretching per week for 12 weeks. The following evaluations were performed before and after the interventions: isokinetic torque of knee extensors and flexors at 300°/s, the Timed Up and Go (TUG) test, the Berg Balance Scale, and the Health Survey assessment (SF-36). [Results] In the intra-group analysis, the EG demonstrated significant improvement in all variables. In the inter-group analysis, the EG demonstrated significant improvement in most variables. [Conclusion] Pilates exercises led to significant improvement in isokinetic torque of the knee extensors and flexors, postural balance and aspects of the health-related quality of life of older adults. PMID:25931749

  8. Both Baseline and Change in Lower Limb Muscle Strength in Younger Women Are Independent Predictors of Balance in Middle Age: A 12-Year Population-Based Prospective Study.

    PubMed

    Wu, Feitong; Callisaya, Michele; Wills, Karen; Laslett, Laura L; Jones, Graeme; Winzenberg, Tania

    2017-06-01

    Poor balance is a risk factor for falls and fracture in older adults, but little is known about modifiable factors affecting balance in younger women. This study aimed to examine whether lower limb muscle strength (LMS) in young women and changes in LMS are independent predictors of balance in middle age. This was an observational 10-year follow-up of 470 women aged 25 to 44 years at baseline who had previously participated in a 2-year population-based randomized controlled trial of osteoporosis education interventions. Linear regression was used to examine the association between baseline LMS (by dynamometer) and change in LMS over 12 years with balance at 12 years (timed up and go test [TUG], step test [ST], functional reach test [FRT], and lateral reach test [LRT]). LMS declined by a mean of 17.3 kg over 12 years. After adjustment for potential confounders, baseline and change in LMS were independently beneficially associated with TUG (β = -0.008 sec/kg, 95% confidence interval [CI] -0.01 to -0.006, and β = -0.006 sec/kg, 95% CI -0.009 to -0.003 for baseline and change, respectively), FRT (β = 0.057 cm/kg, 95% CI 0.030 to 0.084, and β = 0.071 cm/kg, 95% CI 0.042 to 0.101, respectively), and LRT (β = 0.030 cm/kg, 95% CI 0.012 to 0.049, and β = 0.022 cm/kg, 95% CI 0.002 to 0.043, respectively) 12 years later. There was an association between baseline LMS and ST (β = 0.044 steps/kg, 95% CI 0.022 to 0.067) but not between change in LMS and ST. Among young women, greater LMS at baseline and slower decline over time are both associated with better balance in midlife. Analogous to the contributions of peak bone mass and bone loss to fracture risk in older adults, this suggests that both improvement of muscle strength in younger age and prevention of age-related loss of muscle strength could be potentially useful strategies to improve balance and reduce falls in later life. © 2017 American Society for Bone and Mineral

  9. The relationship between performance on the modified star excursion balance test and the knee muscle strength before and after anterior cruciate ligament reconstruction.

    PubMed

    Domingues, Paula Calori; Serenza, Felipe de Souza; Muniz, Thiago Batista; de Oliveira, Luciano Fonseca Lemos; Salim, Rodrigo; Fogagnolo, Fabricio; Kfuri, Mauricio; Ferreira, Aline Miranda

    2018-06-06

    The objective of this study was to evaluate the dynamic balance of the injured and uninjured limb before and after the anterior cruciate ligament (ACL) reconstruction and compare with the control group. Prospective longitudinal. Biomechanics laboratory. Participants are 24 males (mean age, 27.5 years) with unilateral ACL injury (ACLG) and 24 male healthy volunteers (CG). The modified star excursion balance test (SEBT) and isokinetic knee extensor and flexor strength were applied in the ACLG preoperatively and after surgery. The dominant limb of CG was evaluated at a single time. There was no difference between the injured and the uninjured limb of the ACLG (P > 0.05) before and after surgery. Preoperatively, both ACLG limbs had a significantly lower reach distance in posteromedial (PM) and posterolateral (PL) directions and in composite reach (CR) score compared to the control group (P < 0.001). Postoperatively, no significant differences were found between ACLG and CG (P > 0.05). There was a positive correlation between preoperative PL (0.59) and CR (0.51), postoperative PM (0.36), PL (0.36) and CR (0.46) with flexor strength at 12 months after surgery. Patients with ACL injury presented a worse performance in the SEBT in the preoperative period compared to the control group. After ligament reconstruction, the performance in the SEBT became equivalent to that of the control group. The strong correlation between flexor strength and posterior directions of the injured limb demonstrates the importance of the knee flexor muscles in the neuromuscular control of patients submitted to ACL reconstruction. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Home-Based Virtual Reality-Augmented Training Improves Lower Limb Muscle Strength, Balance, and Functional Mobility following Chronic Incomplete Spinal Cord Injury.

    PubMed

    Villiger, Michael; Liviero, Jasmin; Awai, Lea; Stoop, Rahel; Pyk, Pawel; Clijsen, Ron; Curt, Armin; Eng, Kynan; Bolliger, Marc

    2017-01-01

    Key factors positively influencing rehabilitation and functional recovery after spinal cord injury (SCI) include training variety, intensive movement repetition, and motivating training tasks. Systems supporting these aspects may provide profound gains in rehabilitation, independent of the subject's treatment location. In the present study, we test the hypotheses that virtual reality (VR)-augmented training at home (i.e., unsupervised) is feasible with subjects with an incomplete SCI (iSCI) and that it improves motor functions such as lower limb muscle strength, balance, and functional mobility. In the study, 12 chronic iSCI subjects used a home-based, mobile version of a lower limb VR training system. The system included motivating training scenarios and combined action observation and execution. Virtual representations of the legs and feet were controlled via movement sensors. The subjects performed home-based training over 4 weeks, with 16-20 sessions of 30-45 min each. The outcome measures assessed were the Lower Extremity Motor Score (LEMS), Berg Balance Scale (BBS), Timed Up and Go (TUG), Spinal Cord Independence Measure mobility, Walking Index for Spinal Cord Injury II, and 10 m and 6 min walking tests. Two pre-treatment assessment time points were chosen for outcome stability: 4 weeks before treatment and immediately before treatment. At post-assessment (i.e., immediately after treatment), high motivation and positive changes were reported by the subjects (adapted Patients' Global Impression of Change). Significant improvements were shown in lower limb muscle strength (LEMS, P  = 0.008), balance (BBS, P  = 0.008), and functional mobility (TUG, P  = 0.007). At follow-up assessment (i.e., 2-3 months after treatment), functional mobility (TUG) remained significantly improved ( P  = 0.005) in contrast to the other outcome measures. In summary, unsupervised exercises at home with the VR training system led to beneficial functional

  11. Muscle strength at the trunk*.

    PubMed

    Smidt, G L; Amundsen, L R; Dostal, W F

    1980-01-01

    The purpose of this study was to determine the strength of trunk flexors and extensors in normal male subjects during isometric, concentric, and eccentric contractions. Subjects were tested in the sidelying position to minimize the effects of gravity. The pelvis and lower extremities were measured on a custom built force table (lowa Force Table). Muscle strength was expressed as a moment of force (external force times the moment arm) in Newton-meter (Nm) units. Greater Nm were registered in the muscle-lengthened position than in the muscle-shortened position for all isometric contractions. The Nm registered for eccentric contractions always exceeded the Nm registered for concentric contractions of the same muscle group. The Nm registered during contractions of trunk extensors always exceeded the values obtained during corresponding modes of contractions (isometric, eccentric, and concentric) of trunk flexors.J Orthop Sports Phys Ther 1980;1(3):165-170.

  12. Comparison of Walking, Muscle Strength, Balance, and Fear of Falling Between Repeated Fall Group, One-time Fall Group, and Nonfall Group of the Elderly Receiving Home Care Service.

    PubMed

    Jeon, MiYang; Gu, Mee Ock; Yim, JongEun

    2017-12-01

    The purpose of this study was to provide information to develop a program to prevent repeated falls by analyzing the difference in gait, muscle strength, balance, and fear of falling according to their fall experience. The study subjects were 110 elderly individuals aged over 60 years who agreed to their participation in this research. The study participants were categorized into a repeated fall group (n = 40), a one-time fall group (n = 15), and a nonfall group (n = 46) of the elderly. Measurements of gait, muscle strength, balance, and fear of falling were taken in each group. With regard to gait, there were significant differences among three groups in gait cycle (F = 3.50, p = .034), speed (F = 13.06, p < .001), and cadence (F = 5.59, p = .005). Regarding muscle strength in the upper and lower limbs, statistically significant differences were shown among three groups in muscle strength of upper (F = 16.98, p < .001) and lower (F = 10.55, p < .001) limbs. With regard to balance, the nonfall group had significantly greater results than the one-time fall group and repeated fall group in dynamic balance (F = 10.80, p < .001) and static balance (F = 8.20, p = .001). In the case of the fear of falling, the repeated fall group had significantly higher score than other two groups (F = 20.62, p < .001). This study suggests that intervention program should be tailored to fall risk factors to enhance gait and balance and lower body muscle strength and reduce the fear of falling to prevent repeated incidences of falls in this population. Copyright © 2017. Published by Elsevier B.V.

  13. Postural control in elderly persons with osteoporosis: Efficacy of an intervention program to improve balance and muscle strength: a randomized controlled trial.

    PubMed

    Burke, Thomaz Nogueira; França, Fábio Jorge Renovato; Ferreira de Meneses, Sarah Rúbia; Cardoso, Viviam Inhasz; Marques, Amélia Pasqual

    2010-07-01

    To assess the efficacy of an exercise program aiming to improve balance and muscular strength, for postural control and muscular strength of women with osteoporosis. Sample consisted of 33 women with osteoporosis, randomized into one of two groups: intervention group, in which exercises for balance and improvement of muscular strength of the inferior members were performed for 8 wks (n = 17, age 72.8 +/- 3.6 yrs); control group, which was women not practicing exercises (n = 16, age 74.4 +/- 3.7 yrs). At baseline and after 8 wks of treatment, postural control was assessed using a force plate (Balance Master, Neurocom), and muscular strength during ankle dorsiflexion, knee extension, and flexion was assessed by dynamometry. Adherence to the program was 82%. When compared with the control group, individuals in the intervention group significantly improved the center of pressure velocity (P = 0.02) in the modified clinical test of sensory interaction for balance test, center of pressure velocity (P < 0.01), and directional control (P < 0.01) in limits of stability test, isometric force during ankle dorsiflexion (P = 0.01), knee extension (P < 0.01), and knee flexion (P < 0.01). Balance and strength exercises are effective in improving postural control and lower-limb strength in elderly women with osteoporosis.

  14. Relationship between strength, power and balance performance in seniors.

    PubMed

    Muehlbauer, Thomas; Besemer, Carmen; Wehrle, Anja; Gollhofer, Albert; Granacher, Urs

    2012-01-01

    Deficits in strength, power and balance represent important intrinsic risk factors for falls in seniors. The purpose of this study was to investigate the relationship between variables of lower extremity muscle strength/power and balance, assessed under various task conditions. Twenty-four healthy and physically active older adults (mean age: 70 ± 5 years) were tested for their isometric strength (i.e. maximal isometric force of the leg extensors) and muscle power (i.e. countermovement jump height and power) as well as for their steady-state (i.e. unperturbed standing, 10-meter walk), proactive (i.e. Timed Up & Go test, Functional Reach Test) and reactive (i.e. perturbed standing) balance. Balance tests were conducted under single (i.e. standing or walking alone) and dual task conditions (i.e. standing or walking plus cognitive and motor interference task). Significant positive correlations were found between measures of isometric strength and muscle power of the lower extremities (r values ranged between 0.608 and 0.720, p < 0.01). Hardly any significant associations were found between variables of strength, power and balance (i.e. no significant association in 20 out of 21 cases). Additionally, no significant correlations were found between measures of steady-state, proactive and reactive balance or balance tests performed under single and dual task conditions (all p > 0.05). The predominately nonsignificant correlations between different types of balance imply that balance performance is task specific in healthy and physically active seniors. Further, strength, power and balance as well as balance under single and dual task conditions seem to be independent of each other and may have to be tested and trained complementarily. Copyright © 2012 S. Karger AG, Basel.

  15. Pulmonary Function, Muscle Strength and Mortality in Old Age

    PubMed Central

    Buchman, A. S.; Boyle, P. A.; Wilson, R.S.; Gu, Liping; Bienias, Julia L.; Bennett, D. A.

    2009-01-01

    Numerous reports have linked extremity muscle strength with mortality but the mechanism underlying this association is not known. We used data from 960 older persons without dementia participating in the Rush Memory and Aging Project to test two sequential hypotheses: first, that extremity muscle strength is a surrogate for respiratory muscle strength, and second, that the association of respiratory muscle strength with mortality is mediated by pulmonary function. In a series of proportional hazards models, we first demonstrated that the association of extremity muscle strength with mortality was no longer significant after including a term for respiratory muscle strength, controlling for age, sex, education, and body mass index. Next, the association of respiratory muscle strength with mortality was attenuated by more than 50% and no longer significant after including a term for pulmonary function. The findings were unchanged after controlling for cognitive function, parkinsonian signs, physical frailty, balance, physical activity, possible COPD, use of pulmonary medications, vascular risk factors including smoking, chronic vascular diseases, musculoskeletal joint pain, and history of falls. Overall, these findings suggest that pulmonary function may partially account for the association of muscle strength and mortality. PMID:18755207

  16. Effects of intensive whole-body vibration training on muscle strength and balance in adults with chronic stroke: a randomized controlled pilot study.

    PubMed

    Tankisheva, Ekaterina; Bogaerts, An; Boonen, Steven; Feys, Hilde; Verschueren, Sabine

    2014-03-01

    To investigate the effects of a 6-week whole body vibration (WBV) training program in patients with chronic stroke. Randomized controlled pilot trial with 6 weeks' follow-up. University hospital. Adults with chronic stroke (N=15) were randomly assigned to an intervention (n=7) or a control group (n=8). Supervised, intensive WBV training. The vibration group performed a variety of static and dynamic squat exercises on a vibration platform with vibration amplitudes of 1.7 and 2.5mm and frequencies of 35 and 40Hz. The vibration lasted 30 to 60 seconds, with 5 to 17 repetitions per exercise 3 times weekly for 6 weeks. Participants in the control group continued their usual activities and were not involved in any additional training program. The primary outcome variable was the isometric and isokinetic muscle strength of the quadriceps (isokinetic dynamometer). Additionally, hamstrings muscle strength, static and dynamic postural control (dynamic posturography), and muscle spasticity (Ashworth Scale) were assessed. Compliance with the vibration intervention was excellent, and the participants completed all 18 training sessions. Vibration frequencies of both 35 and 40Hz were well tolerated by the patients, and no adverse effects resulting from the vibration were noted. Overall, the effect of intensive WBV intervention resulted in significant between-group differences in favor of the vibration group only in isometric knee extension strength (knee angle, 60°) (P=.022) after 6 weeks of intervention and in isokinetic knee extension strength (velocity, 240°/s) after a 6-week follow-up period (P=.005), both for the paretic leg. Postural control improved after 6 weeks of vibration in the intervention group when the patients had normal vision and a sway-referenced support surface (P<.05). Muscle spasticity was not affected by vibration (P>.05). These preliminary results suggest that intensive WBV might potentially be a safe and feasible way to increase some aspect of lower

  17. Promoting balance and strength in the middle-aged workforce.

    PubMed

    Granacher, U; Wick, C; Rueck, N; Esposito, C; Roth, R; Zahner, L

    2011-01-01

    The prevalence of sustaining fall-related injuries is high in the middle-aged workforce. Deficits in postural control/muscle strength represent important fall-risk factors. The objective of this study was to examine the impact of balance and strength training followed by detraining on postural control and muscle strength in the workforce. Thirty-two adults with sedentary office work participated in this study and were assigned to an intervention (age 56.0 ± 3.7 yrs) or a control group (age 55.5 ± 3.4 yrs). The intervention group participated in 8 weeks of balance and strength training conducted at the worksite, followed by 8 weeks of detraining. Tests included the measurement of (a) total centre of pressure (COP) displacements during one-legged standing, (b) gait velocity and stride-to-stride variability, (c) peak isometric/isokinetic torque and rate of torque development (RTD) of the plantar flexors, and (d) jumping height. After training, significant improvements in COP displacements, gait velocity, peak isometric/isokinetic torque, RTD, and jumping height were observed. During detraining, muscle strength deteriorated, whereas postural control improved. This fall-preventive training program conducted at the worksite proved to be feasible and effective. It is suggested that this training program should be permanently conducted to maintain/improve muscle strength. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Analysis of muscle activation in lower extremity for static balance.

    PubMed

    Chakravarty, Kingshuk; Chatterjee, Debatri; Das, Rajat Kumar; Tripathy, Soumya Ranjan; Sinha, Aniruddha

    2017-07-01

    Balance plays an important role for human bipedal locomotion. Degeneration of balance control is prominent in stroke patients, elderly adults and even for majority of obese people. Design of personalized balance training program, in order to strengthen muscles, requires the analysis of muscle activation during an activity. In this paper we have proposed an affordable and portable approach to analyze the relationship between the static balance strategy and activation of various lower extremity muscles. To do that we have considered Microsoft Kinect XBox 360 as a motion sensing device and Wii balance board for measuring external force information. For analyzing the muscle activation pattern related to static balance, participants are asked to do the single limb stance (SLS) exercise on the balance board and in front of the Kinect. Static optimization to minimize the overall muscle activation pattern is carried out using OpenSim, which is an open-source musculoskeletal simulation software. The study is done on ten normal and ten obese people, grouped according to body mass index (BMI). Results suggest that the lower extremity muscles like biceps femoris, psoas major, sartorius, iliacus play the major role for both maintaining the balance using one limb as well as maintaining the flexion of the other limb during SLS. Further investigations reveal that the higher muscle activations of the flexed leg for normal group demonstrate higher strength. Moreover, the lower muscle activation of the standing leg for normal group demonstrate more headroom for the biceps femoris-short-head and psoas major to withstand the load and hence have better static balance control.

  19. Personality Typology in Relation to Muscle Strength

    PubMed Central

    Terracciano, Antonio; Milaneschi, Yuri; Metter, E. Jeffrey; Ferrucci, Luigi

    2011-01-01

    Background Physical inactivity plays a central role in the age-related decline in muscle strength, an important component in the process leading to disability. Personality, a significant determinant of health behaviors including physical activity, could therefore impact muscle strength throughout adulthood and affect the rate of muscle strength decline with aging. Personality typologies combining “high neuroticism” (N≥55), “low extraversion” (E<45), and “low conscientiousness” (C<45) have been associated with multiple risky health behaviors but have not been investigated with regards to muscle strength. Purpose The purpose of this study is to investigate associations between individual and combined typologies consisting of high N, low E, and low C and muscle strength, and whether physical activity and body mass index act as mediators. Method This cross-sectional study includes 1,220 participants from the Baltimore Longitudinal Study of Aging. Results High N was found among 18%, low E among 31%, and low C among 26% of the sample. High levels of N, particularly when combined with either low E or low C, were associated with lower muscle strength compared with having only one or none of these personality types. Facet analyses suggest an important role for the N components of depression and hostility. Physical activity level appears to partly explain some of these associations. Conclusion Findings provide support for the notion that the typological approach to personality may be useful in identifying specific personality types at risk of low muscle strength and offer the possibility for more targeted prevention and intervention programs. PMID:21614452

  20. Strength and fatigability of selected muscles in upper limb: assessing muscle imbalance relevant to tennis elbow.

    PubMed

    Alizadehkhaiyat, O; Fisher, A C; Kemp, G J; Frostick, S P

    2007-08-01

    The aetiology of tennis elbow has remained uncertain for more than a century. To examine muscle imbalance as a possible pathophysiological factor requires a reliable method of assessment. This paper describes the development of such a method and its performance in healthy subjects. We propose a combination of surface and fine-wire EMG of shoulder and forearm muscles and wrist strength measurements as a reliable tool for assessing muscle imbalance relevant to the pathophysiology of tennis elbow. Six healthy volunteers participated. EMG data were acquired at 50% maximal voluntary isometric contraction from five forearm muscles during grip and three shoulder muscles during external rotation and abduction, and analysed using normalized median frequency slope as a fatigue index. Wrist extension/flexion strength was measured using a purpose-built dynamometer. Significant negative slope of median frequency was found for all muscles, with good reproducibility, and no significant difference in slope between the different muscles of the shoulder and the wrist. (Amplitude slope showed high variability and was therefore unsuitable for this purpose.) Wrist flexion was 27+/-8% stronger than extension (mean+/-SEM, p=0.006). This is a reliable method for measuring muscle fatigue in forearm and shoulder. EMG and wrist strength studies together can be used for assessing and identifying the muscle balance in the wrist-forearm-shoulder chain.

  1. Rotator cuff strength balance in glovebox workers

    DOE PAGES

    Lawton, Cindy M.; Weaver, Amelia M.; Chan, Martha Kwan Yi; ...

    2016-11-23

    Gloveboxes are essential to the pharmaceutical, semi-conductor, nuclear, and biochemical industries. While gloveboxes serve as effective containment systems, they are often difficult to work in and present a number of ergonomic hazards. One such hazard is injury to the rotator cuff, a group of tendons and muscles in the shoulder, connecting the upper arm to the shoulder blade. Rotator cuff integrity is critical to shoulder health. This study compared the rotator cuff muscle strength ratios of glovebox workers to the healthy norm. Descriptive statistics were collected using a short questionnaire. Handheld dynamometry was used to quantify the ratio of forcesmore » produced for shoulder internal and external rotation. Results showed this population to have shoulder strength ratios significantly different from the healthy norm. Strength ratios were found to be a sound predictor of symptom incidence. The deviation from the normal ratio demonstrates the need for solutions designed to reduce the workload on the rotator cuff musculature in order to improve health and safety. Assessment of strength ratios can be used to screen for risk of symptom development. As a result, this increases technical knowledge and augments operational safety.« less

  2. Rotator cuff strength balance in glovebox workers

    SciTech Connect

    Lawton, Cindy M.; Weaver, Amelia M.; Chan, Martha Kwan Yi

    Gloveboxes are essential to the pharmaceutical, semi-conductor, nuclear, and biochemical industries. While gloveboxes serve as effective containment systems, they are often difficult to work in and present a number of ergonomic hazards. One such hazard is injury to the rotator cuff, a group of tendons and muscles in the shoulder, connecting the upper arm to the shoulder blade. Rotator cuff integrity is critical to shoulder health. This study compared the rotator cuff muscle strength ratios of glovebox workers to the healthy norm. Descriptive statistics were collected using a short questionnaire. Handheld dynamometry was used to quantify the ratio of forcesmore » produced for shoulder internal and external rotation. Results showed this population to have shoulder strength ratios significantly different from the healthy norm. Strength ratios were found to be a sound predictor of symptom incidence. The deviation from the normal ratio demonstrates the need for solutions designed to reduce the workload on the rotator cuff musculature in order to improve health and safety. Assessment of strength ratios can be used to screen for risk of symptom development. As a result, this increases technical knowledge and augments operational safety.« less

  3. The effects of pilates on balance, mobility and strength in patients with multiple sclerosis.

    PubMed

    Guclu-Gunduz, Arzu; Citaker, Seyit; Irkec, Ceyla; Nazliel, Bijen; Batur-Caglayan, Hale Zeynep

    2014-01-01

    Although there are evidences as to Pilates developing dynamic balance, muscle strength and flexibility in healthy people, evidences related to its effects on Multiple Sclerosis patients are insufficient. The aims of this study were to investigate the effects of Pilates on balance, mobility, and strength in ambulatory patients with Multiple Sclerosis. Twenty six patients were divided into two groups as experimental (n = 18) and control (n = 8) groups for an 8-week treatment program. The experimental group underwent Pilates and the control group did abdominal breathing and active extremity exercises at home. Balance and mobility were measured with Berg Balance Scale and Timed up and go test, upper and lower muscle strength with hand-held dynamometer. Confidence in balance skills while performing daily activities was evaluated with Activities Specific Balance Confidence Scale. Improvements were observed in balance, mobility, and upper and lower extremity muscle strength in the Pilates group (p < 0.05). No significant differences in any outcome measures were observed in the control group (p > 0.05). Due to its structure which is made up of balance and strengthening exercises, Pilates training may develop balance, mobility and muscle strength of MS patients. For this reason, we think that, Pilates exercises which are appropriate for the disability level of the patient may be suggested.

  4. The impact of obesity on skeletal muscle strength and structure through adolescence to old age.

    PubMed

    Tomlinson, D J; Erskine, R M; Morse, C I; Winwood, K; Onambélé-Pearson, Gladys

    2016-06-01

    Obesity is associated with functional limitations in muscle performance and increased likelihood of developing a functional disability such as mobility, strength, postural and dynamic balance limitations. The consensus is that obese individuals, regardless of age, have a greater absolute maximum muscle strength compared to non-obese persons, suggesting that increased adiposity acts as a chronic overload stimulus on the antigravity muscles (e.g., quadriceps and calf), thus increasing muscle size and strength. However, when maximum muscular strength is normalised to body mass, obese individuals appear weaker. This relative weakness may be caused by reduced mobility, neural adaptations and changes in muscle morphology. Discrepancies in the literature remain for maximal strength normalised to muscle mass (muscle quality) and can potentially be explained through accounting for the measurement protocol contributing to muscle strength capacity that need to be explored in more depth such as antagonist muscle co-activation, muscle architecture, a criterion valid measurement of muscle size and an accurate measurement of physical activity levels. Current evidence demonstrating the effect of obesity on muscle quality is limited. These factors not being recorded in some of the existing literature suggest a potential underestimation of muscle force either in terms of absolute force production or relative to muscle mass; thus the true effect of obesity upon skeletal muscle size, structure and function, including any interactions with ageing effects, remains to be elucidated.

  5. Mechanisms of protein balance in skeletal muscle.

    PubMed

    Anthony, T G

    2016-07-01

    Increased global demand for adequate protein nutrition against a backdrop of climate change and concern for animal agriculture sustainability necessitates new and more efficient approaches to livestock growth and production. Anabolic growth is achieved when rates of new synthesis exceed turnover, producing a positive net protein balance. Conversely, deterioration or atrophy of lean mass is a consequence of a net negative protein balance. During early life and periods of growth, muscle mass is driven by increases in protein synthesis at the level of mRNA translation. Throughout life, muscle mass is further influenced by degradative processes such as autophagy and the ubiquitin proteasome pathway. Multiple signal transduction networks guide and coordinate these processes alongside quality control mechanisms to maintain protein homeostasis (proteostasis). Genetics, hormones, and environmental stimuli each influence proteostasis control, altering capacity and/or efficiency of muscle growth. An overview of recent findings and current methods to assess muscle protein balance and proteostasis is presented. Current efforts to identify novel control points have the potential through selective breeding design or development of hormetic strategies to better promote growth and health span during environmental stress. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Importance and challenges of measuring intrinsic foot muscle strength

    PubMed Central

    2012-01-01

    Background Intrinsic foot muscle weakness has been implicated in a range of foot deformities and disorders. However, to establish a relationship between intrinsic muscle weakness and foot pathology, an objective measure of intrinsic muscle strength is needed. The aim of this review was to provide an overview of the anatomy and role of intrinsic foot muscles, implications of intrinsic weakness and evaluate the different methods used to measure intrinsic foot muscle strength. Method Literature was sourced from database searches of MEDLINE, PubMed, SCOPUS, Cochrane Library, PEDro and CINAHL up to June 2012. Results There is no widely accepted method of measuring intrinsic foot muscle strength. Methods to estimate toe flexor muscle strength include the paper grip test, plantar pressure, toe dynamometry, and the intrinsic positive test. Hand-held dynamometry has excellent interrater and intrarater reliability and limits toe curling, which is an action hypothesised to activate extrinsic toe flexor muscles. However, it is unclear whether any method can actually isolate intrinsic muscle strength. Also most methods measure only toe flexor strength and other actions such as toe extension and abduction have not been adequately assessed. Indirect methods to investigate intrinsic muscle structure and performance include CT, ultrasonography, MRI, EMG, and muscle biopsy. Indirect methods often discriminate between intrinsic and extrinsic muscles, but lack the ability to measure muscle force. Conclusions There are many challenges to accurately measure intrinsic muscle strength in isolation. Most studies have measured toe flexor strength as a surrogate measure of intrinsic muscle strength. Hand-held dynamometry appears to be a promising method of estimating intrinsic muscle strength. However, the contribution of extrinsic muscles cannot be excluded from toe flexor strength measurement. Future research should clarify the relative contribution of intrinsic and extrinsic muscles

  7. Is muscular strength balance influenced by menstrual cycle in female soccer players?

    PubMed

    Dos Santos Andrade, Marília; Mascarin, Naryana C; Foster, Roberta; de Jármy di Bella, Zsuzsanna I; Vancini, Rodrigo L; Barbosa de Lira, Claudio A

    2017-06-01

    Muscular strength imbalance is an important risk factor for ACL injury, but it is not clear the impact of menstrual cycle on muscular strength balance. Our aims were to compare muscular balance (hamstring-to-quadriceps peak torque strength balance ratio) between luteal and follicular phases and compare gender differences relative to strength balance to observe possible fluctuations in strength balance ratio. Thirty-eight soccer athletes (26 women and 12 men) took part in this study. Athletes participated in two identical isokinetic strength evaluations for both knee (non-dominant [ND] and dominant [D]). Peak torque for quadriceps and hamstring muscles were measured in concentric mode and hamstring-to-quadriceps peak torque strength balance ratio calculated. Women had significantly lower hamstring-to-quadriceps peak torque strength balance ratio during the follicular compared to luteal phase, for the ND limb (P=0.011). However, no differences, between luteal and follicular phases, were observed in the D limb. In men, no difference in strength balance ratios was found between the ND and D limbs. These data may be useful in prevention programs for knee (ACL) injuries among soccer female athletes.

  8. Autism Severity and Muscle Strength: A Correlation Analysis

    ERIC Educational Resources Information Center

    Kern, Janet K.; Geier, David A.; Adams, James B.; Troutman, Melissa R.; Davis, Georgia; King, Paul G.; Young, John L.; Geier, Mark R.

    2011-01-01

    The current study examined the relationship between muscle strength, as measured by hand grip strength, and autism severity, as measured by the Childhood Autism Rating Scale (CARS). Thirty-seven (37) children with a diagnosis of autism spectrum disorder (ASD) were evaluated using the CARS and then tested for hand muscle strength using a hand grip…

  9. Balance and muscle power of children with Charcot-Marie-Tooth.

    PubMed

    Silva, Tais R; Testa, Amanda; Baptista, Cyntia R J A; Marques, Wilson; Mattiello-Sverzut, Ana C

    2014-01-01

    In certain diseases, functional constraints establish a greater relationship with muscle power than muscle strength. However, in hereditary peripheral polyneuropathies, no such relationship was found in the literature. In children with Charcot-Marie-Tooth (CMT), to identify the impact of muscle strength and range of movement on the static/dynamic balance and standing long jump based on quantitative and functional variables. The study analyzed 19 participants aged between 6 and 16 years, of both genders and with clinical diagnoses of CMT of different subtypes. Anthropometric data, muscle strength of the lower limbs (hand-held dynamometer), ankle and knee range of movement, balance (Pediatric Balance Scale) and standing long jump distance were obtained by standardized procedures. For the statistical analysis, Pearson and Spearman correlation coefficients were used. There was a strong positive correlation between balance and the muscle strength of the right plantar flexors (r=0.61) and dorsiflexors (r=0.59) and a moderate correlation between balance and the muscle strength of inversion (r=0.41) and eversion of the right foot (r=0.44). For the long jump and range of movement, there was a weak positive correlation with right and left plantar flexion (r=0.20 and r=0.12, respectively) and left popliteal angle (r=0.25), and a poor negative correlation with left dorsiflexion (r=-0.15). The data on the patients analyzed suggests that the maintenance of distal muscle strength favors performance during balance tasks, while limitations in the range of movement of the legs seem not to be enough to influence the performance of the horizontal long jump.

  10. Knee flexor strength and balance control impairment may explain declines during prolonged walking in women with mild multiple sclerosis.

    PubMed

    Ramari, Cintia; Moraes, Andréa G; Tauil, Carlos B; von Glehn, Felipe; Motl, Robert; de David, Ana C

    2018-02-01

    Physiological factors such as muscle weakness and balance could explain declines in walking distance by multiple sclerosis (MS) patients. The purpose of this study was to characterize levels and examine associations among decline in walking distance, balance and muscular strength in women with mild MS. Participants included 28 women with mild relapsing-remitting MS and 21 women without MS. We executed the 6-min walk test (6MWT) to verify declines in walking distance. Isokinetic knee flexion (KF) and extension (KE) muscle strength was measured using a dynamometer. Balance was quantified using a force platform, with eyes open and closed, on a rigid and foam surface. The MS patients presented declines in walking, lower KF muscle strength, and worse balance than controls. KF strength and balance correlated with walking in the MS group. The KF strength explained differences between groups in walking. The KF strength and balance presented as predictors of walking slowing down in the 6MWT, in mild MS. Women with mild MS have strength impairment of knee flexor muscles and balance control impairment that may explain walking related motor fatigability during prolonged walking. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Ankle muscle strength discriminates fallers from non-fallers

    PubMed Central

    Cattagni, Thomas; Scaglioni, Gil; Laroche, Davy; Van Hoecke, Jacques; Gremeaux, Vincent; Martin, Alain

    2014-01-01

    It is well known that center of pressure (CoP) displacement correlates negatively with the maximal isometric torque (MIT) of ankle muscles. This relationship has never been investigated in elderly fallers (EF). The purpose of this study was thus to analyze the relationship between the MIT of ankle muscles and CoP displacement in upright stance in a sample aged between 18 and 90 years old that included EF. The aim was to identify a threshold of torque below which balance is compromised. The MIT of Plantar flexors (PFs) and dorsal flexors (DFs) and CoP were measured in 90 volunteers: 21 healthy young adults (YA) (age: 24.1 ± 5.0), 12 healthy middle-aged adults (MAA) (age: 50.2 ± 4.5), 27 healthy elderly non-fallers (ENF) (age: 75.5 ± 7.0) and 30 EF (age: 78.8 ± 6.7). The MIT of PF and DF were summed to obtain the overall maximal ankle muscle strength. Body weight and height were used to normalize MIT (nMIT) and CoP (nCoP), respectively. nCoP correlated negatively with nMIT. 90% of EF generated an nMIT <3.1 N·m·kg−1, whereas 85% of non-fallers generated an nMIT >3.1 N·m·kg−1. The relationship between nMIT and nCoP implies that ankle muscle weakness contributes to increased postural instability and the risk of falling. We observed that below the threshold of 3.1 N·m·kg−1, postural stability was dramatically diminished and balance was compromised. Our results suggest that measuring ankle torque could be used in routine clinical practice to identify potential fallers. PMID:25566068

  12. Dynamic balance ability in young elite soccer players: implication of isometric strength.

    PubMed

    Chtara, Moktar; Rouissi, Mehdi; Bragazzi, Nicola L; Owen, Adam L; Haddad, Monoem; Chamari, Karim

    2018-04-01

    Soccer requires maintaining unilateral balance when executing movement with the contralateral leg. Despite the fact that balance requires standing with maintaining isometric posture with the support leg, currently there is a lack of studies regarding the implication of isometric strength on dynamic balance's performance among young soccer players. Therefore, the aim of this study was to examine the relationship between the Y-Balance Test and 12 lower limbs isometric strength tests. Twenty-six right footed soccer players (mean±SD, age=16.2±1.6 years, height=175±4.2 cm, body mass=68.8±6.1 kg) performed a dynamic balance test (star excursion balance-test with dominant- (DL) and nondominant-legs (NDL). Furthermore, maximal isometric contraction tests of 12 lower limb muscle groups were assessed in DL and NDL. Correlations analysis reported a significant positive relationship between some of isometric strength tests (with DL and NDL) and the Y-Balance Test. Furthermore, stepwise multiple regression analysis showed that maximal isometric strength explained between 21.9% and 49.4% of the variance of the Y-Balance Test. Moreover, maximal isometric strength was dependent upon the reaching angle of the Y-Balance Test and the leg used to support body weight. This study showed a significant implication of maximal isometric strength of the lower limb and the Y-Balance Test. Moreover, the present investigation suggests the implementation of specific lower limb strengthening exercises depending on players' deficit in each reaching direction and leg. This result suggests that further studies should experiment if increasing lower limbs isometric strength could improve dynamic balance ability among young soccer players.

  13. Objective Evaluation of Muscle Strength in Infants with Hypotonia and Muscle Weakness

    ERIC Educational Resources Information Center

    Reus, Linda; van Vlimmeren, Leo A.; Staal, J. Bart; Janssen, Anjo J. W. M.; Otten, Barto J.; Pelzer, Ben J.; Nijhuis-van der Sanden, Maria W. G.

    2013-01-01

    The clinical evaluation of an infant with motor delay, muscle weakness, and/or hypotonia would improve considerably if muscle strength could be measured objectively and normal reference values were available. The authors developed a method to measure muscle strength in infants and tested 81 typically developing infants, 6-36 months of age, and 17…

  14. Cycle training induces muscle hypertrophy and strength gain: strategies and mechanisms.

    PubMed

    Ozaki, Hayao; Loenneke, J P; Thiebaud, R S; Abe, T

    2015-03-01

    Cycle training is widely performed as a major part of any exercise program seeking to improve aerobic capacity and cardiovascular health. However, the effect of cycle training on muscle size and strength gain still requires further insight, even though it is known that professional cyclists display larger muscle size compared to controls. Therefore, the purpose of this review is to discuss the effects of cycle training on muscle size and strength of the lower extremity and the possible mechanisms for increasing muscle size with cycle training. It is plausible that cycle training requires a longer period to significantly increase muscle size compared to typical resistance training due to a much slower hypertrophy rate. Cycle training induces muscle hypertrophy similarly between young and older age groups, while strength gain seems to favor older adults, which suggests that the probability for improving in muscle quality appears to be higher in older adults compared to young adults. For young adults, higher-intensity intermittent cycling may be required to achieve strength gains. It also appears that muscle hypertrophy induced by cycle training results from the positive changes in muscle protein net balance.

  15. Respiratory Muscle Strength Predicts Decline in Mobility in Older Persons

    PubMed Central

    Buchman, A.S.; Boyle, P.A.; Wilson, R.S.; Leurgans, S.; Shah, R.C.; Bennett, D.A.

    2008-01-01

    Objectives To test the hypothesis that respiratory muscle strength is associated with the rate of change in mobility even after controlling for leg strength and physical activity. Methods Prospective study of 890 ambulatory older persons without dementia who underwent annual clinical evaluations to examine change in the rate of mobility over time. Results In a linear mixed-effect model adjusted for age, sex, and education, mobility declined about 0.12 unit/year, and higher levels of respiratory muscle strength were associated with a slower rate of mobility decline (estimate 0.043, SE 0.012, p < 0.001). Respiratory muscle strength remained associated with the rate of change in mobility even after controlling for lower extremity strength (estimate 0.036, SE 0.012, p = 0.004). In a model that included terms for respiratory muscle strength, lower extremity strength and physical activity together, all three were independent predictors of mobility decline in older persons. These associations remained significant even after controlling for body composition, global cognition, the development of dementia, parkinsonian signs, possible pulmonary disease, smoking, joint pain and chronic diseases. Conclusion Respiratory muscle strength is associated with mobility decline in older persons independent of lower extremity strength and physical activity. Clinical interventions to improve respiratory muscle strength may decrease the burden of mobility impairment in the elderly. PMID:18784416

  16. Predictors of chronic ankle instability: Analysis of peroneal reaction time, dynamic balance and isokinetic strength.

    PubMed

    Sierra-Guzmán, Rafael; Jiménez, Fernando; Abián-Vicén, Javier

    2018-05-01

    Previous studies have reported the factors contributing to chronic ankle instability, which could lead to more effective treatments. However, factors such as the reflex response and ankle muscle strength have not been taken into account in previous investigations. Fifty recreational athletes with chronic ankle instability and 55 healthy controls were recruited. Peroneal reaction time in response to sudden inversion, isokinetic evertor muscle strength and dynamic balance with the Star Excursion Balance Test and the Biodex Stability System were measured. The relationship between the Cumberland Ankle Instability Tool score and performance on each test was assessed and a backward multiple linear regression analysis was conducted. Participants with chronic ankle instability showed prolonged peroneal reaction time, poor performance in the Biodex Stability System and decreased reach distance in the Star Excursion Balance Test. No significant differences were found in eversion and inversion peak torque. Moderate correlations were found between the Cumberland Ankle Instability Tool score and the peroneal reaction time and performance on the Star Excursion Balance Test. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test accounted for 36% of the variance in the Cumberland Ankle Instability Tool. Dynamic balance deficits and delayed peroneal reaction time are present in participants with chronic ankle instability. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test were the main contributing factors to the Cumberland Ankle Instability Tool score. No clear strength impairments were reported in unstable ankles. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Functional polymorphisms associated with human muscle size and strength.

    PubMed

    Thompson, Paul D; Moyna, Niall; Seip, Richard; Price, Thomas; Clarkson, Priscilla; Angelopoulos, Theodore; Gordon, Paul; Pescatello, Linda; Visich, Paul; Zoeller, Robert; Devaney, Joseph M; Gordish, Heather; Bilbie, Stephen; Hoffman, Eric P

    2004-07-01

    Skeletal muscle is critically important to human performance and health, but little is known of the genetic factors influencing muscle size, strength, and its response to exercise training. The Functional single nucleotide polymorphisms (SNP) Associated with Muscle Size and Strength, or FAMuSS, Study is a multicenter, NIH-funded program to examine the influence of gene polymorphisms on skeletal muscle size and strength before and after resistance exercise training. One thousand men and women, age 18 - 40 yr, will train their nondominant arm for 12 wk. Skeletal muscle size (magnetic resonance imaging) and isometric and dynamic strength will be measured before and after training. Individuals whose baseline values or response to training deviate > or = 1.5 SD will be defined as outliers and examined for genetic variants. Initially candidate genes previously associated with muscle performance will be examined, but the study will ultimately attempt to identify genes associated with muscle performance. FAMuSS should help identify genetic factors associated with muscle performance and the response to exercise training. Such insight should contribute to our ability to predict the individual response to exercise training but may also contribute to understanding better muscle physiology, to identifying individuals who are susceptible to muscle loss with environmental challenge, and to developing pharmacologic agents capable of preserving muscle size and function.

  18. Pulmonary Function, Muscle Strength, and Incident Mobility Disability in Elders

    PubMed Central

    Buchman, Aron S.; Boyle, Patricia A.; Leurgans, Sue E.; Evans, Denis A.; Bennett, David A.

    2009-01-01

    Muscle strength, including leg strength and respiratory muscle strength, are relatively independently associated with mobility disability in elders. However, the factors linking muscle strength with mobility disability are unknown. To test the hypothesis that pulmonary function mediates the association of muscle strength with the development of mobility disability in elders, we used data from a longitudinal cohort study of 844 ambulatory elders without dementia participating in the Rush Memory and Aging Project with a mean follow-up of 4.0 years (SD = 1.39). A composite measure of pulmonary function was based on spirometric measures of forced vital capacity, forced expiratory volume, and peak expiratory flow. Respiratory muscle strength was based on maximal inspiratory pressure and expiratory pressure and leg strength based on hand-held dynamometry. Mobility disability was defined as a gait speed less than or equal to 0.55 m/s based on annual assessment of timed walk. Secondary analyses considered time to loss of the ability to ambulate. In separate proportional hazards models which controlled for age, sex, and education, composite measures of pulmonary function, respiratory muscle strength, and leg strength were each associated with incident mobility disability (all P values < 0.001). Further, all three were related to the development of incident mobility disability when considered together in a single model (pulmonary function: hazard ratio [HR], 0.721; 95% confidence interval [CI], 0.577, 0.902; respiratory muscle strength: HR, 0.732; 95% CI, 0.593, 0.905; leg strength: HR, 0.791; 95% CI, 0.640, 0.976). Secondary analyses examining incident loss of the ability to ambulate revealed similar findings. Overall, these findings suggest that lower levels of pulmonary function and muscle strength are relatively independently associated with the development of mobility disability in the elderly. PMID:19934353

  19. Muscle Strength and Muscle Mass in Older Patients during Hospitalization: The EMPOWER Study

    PubMed Central

    Van Ancum, Jeanine M.; Scheerman, Kira; Pierik, Vincent D.; Numans, Siger T.; Verlaan, Sjors; Smeenk, Hanne E.; Slee-Valentijn, Monique; Kruizinga, Roeliene C.; Meskers, Carel G.M.; Maier, Andrea B.

    2017-01-01

    Background Low muscle strength and muscle mass are associated with an increased length of hospital stay and higher mortality rate in inpatients. To what extent hospitalization affects muscle strength and muscle mass is unclear. Objective We aimed to assess muscle strength and muscle mass at admission and during hospitalization in older patients and its relation with being at risk of geriatric conditions. Methods The EMPOWER study included patients aged 70 years and older, admitted to 4 wards of the VU University Medical Center in the Netherlands between April and December 2015. At admission, patients were screened for being at risk of 4 geriatric conditions: delirium, falls, malnutrition, and functional disability. At admission and at discharge, muscle strength and muscle mass were assessed. Results A total of 373 patients (mean age, standard deviation [SD]: 79.6, 6.38 years) were included at admission, and 224 patients (mean age, SD: 80.1, 6.32 years) at discharge. At admission, lower muscle strength in both female and male patients and low muscle mass in male patients were associated with being at risk of a higher cumulative number of geriatric conditions. Muscle strength increased during hospitalization, but no change in muscle mass was observed. Changes in muscle measures were not associated with being at risk of geriatric conditions. Discussion Older patients with lower muscle strength and muscle mass at admission were at risk of a higher cumulative number of geriatric conditions. However, being at risk of geriatric conditions did not forecast further decrease in muscle strength and muscle mass during hospitalization PMID:28817825

  20. Muscle Strength and Muscle Mass in Older Patients during Hospitalization: The EMPOWER Study.

    PubMed

    Van Ancum, Jeanine M; Scheerman, Kira; Pierik, Vincent D; Numans, Siger T; Verlaan, Sjors; Smeenk, Hanne E; Slee-Valentijn, Monique; Kruizinga, Roeliene C; Meskers, Carel G M; Maier, Andrea B

    2017-01-01

    Low muscle strength and muscle mass are associated with an increased length of hospital stay and higher mortality rate in inpatients. To what extent hospitalization affects muscle strength and muscle mass is unclear. We aimed to assess muscle strength and muscle mass at admission and during hospitalization in older patients and its relation with being at risk of geriatric conditions. The EMPOWER study included patients aged 70 years and older, admitted to 4 wards of the VU University Medical Center in the Netherlands between April and December 2015. At admission, patients were screened for being at risk of 4 geriatric conditions: delirium, falls, malnutrition, and functional disability. At admission and at discharge, muscle strength and muscle mass were assessed. A total of 373 patients (mean age, standard deviation [SD]: 79.6, 6.38 years) were included at admission, and 224 patients (mean age, SD: 80.1, 6.32 years) at discharge. At admission, lower muscle strength in both female and male patients and low muscle mass in male patients were associated with being at risk of a higher cumulative number of geriatric conditions. Muscle strength increased during hospitalization, but no change in muscle mass was observed. Changes in muscle measures were not associated with being at risk of geriatric conditions. Older patients with lower muscle strength and muscle mass at admission were at risk of a higher cumulative number of geriatric conditions. However, being at risk of geriatric conditions did not forecast further decrease in muscle strength and muscle mass during hospitalization. © 2017 The Author(s) Published by S. Karger AG, Basel.

  1. Lower Cognitive Function in Older Patients with Lower Muscle Strength and Muscle Mass.

    PubMed

    van Dam, Romee; Van Ancum, Jeanine M; Verlaan, Sjors; Scheerman, Kira; Meskers, Carel G M; Maier, Andrea B

    2018-06-18

    Low muscle strength and muscle mass are associated with adverse outcomes in older hospitalized patients. The aim of this study was to assess the association between cognitive functioning and muscle strength and muscle mass in hospitalized older patients. This prospective inception cohort included 378 patients aged 70 years or older. At admission patients were assessed for cognitive functioning by use of the Six-Item Cognitive Impairment Test (6-CIT). Muscle strength and muscle mass were assessed using handheld dynamometry and segmental multifrequency bioelectrical impedance analysis, within 48 h after admission and on day 7, or earlier on the day of discharge. The data of 371 patients (mean age ± standard deviation 80.1 ± 6.4 years, 49.3% female) were available for analyses. The median (interquartile range) 6-CIT score was 4 (0-8) points. At admission, lower cognitive functioning was associated with lower muscle strength, lower skeletal muscle mass (SMM), lower appendicular lean mass, and lower SMM index. Cognitive functioning was not associated with change in muscle strength and muscle mass during hospitalization. This study further strengthens evidence for an association between lower cognitive functioning and lower muscle strength and muscle mass, but without a further decline during hospitalization. © 2018 The Author(s) Published by S. Karger AG, Basel.

  2. Association of balance, strength, and power measures in young adults.

    PubMed

    Muehlbauer, Thomas; Gollhofer, Albert; Granacher, Urs

    2013-03-01

    The purpose of this study was to investigate the relationship between variables of static/dynamic balance, isometric strength, and power. Twenty-seven young healthy adults (mean age: 23 ± 4 years) performed measurements of static (unperturbed)/dynamic (perturbed) balance, isometric strength (i.e., maximal isometric torque [MIT]; rate of torque development [RTD] of the plantar flexor), and power (i.e., countermovement jump [CMJ] height and power). No significant associations were found between variables of static and dynamic balance (r = -0.090 to +0.329, p > 0.05) and between measures of static/dynamic balance and isometric strength (r = +0.041 to +0.387, p > 0.05) and static/dynamic balance and power (r = -0.076 to +0.218, p > 0.05). Significant positive correlations (r) were detected between variables of power and isometric strength ranging from +0.458 to +0.689 (p < 0.05). Furthermore, simple regression analyses revealed that a 10% increase in mean CMJ height (4.1 cm) was associated with 22.9 N·m and 128.4 N·m·s better MIT and RTD, respectively. The nonsignificant correlation between static and dynamic balance measures and between static/dynamic balance, isometric strength, and power variables implies that these capacities may be independent of each other and may have to be tested and trained complementarily.

  3. Evaluation of rotator cuff muscle strength in healthy individuals

    PubMed Central

    Cortez, Paulo José Oliveira; Tomazini, José Elias

    2015-01-01

    OBJECTIVE: To compare the strength generated by the rotator muscles of the shoulder joint between the right upper limb and left upper limb among healthy individuals. METHODS: To evaluate the muscle strength of upper limbs from isometric contractions in the horizontal direction (rotation) an isometric dynamometer was used, equipped with transducers, signal conditioning, a data acquisition board, and finally, a computer. Study participants were 22 male military subjects, aged between 18 and 19 years old, body mass between 57.7 and 93.0 kg (71.8 ± 9.45 kg) and height between 1.67 and 1.90 m (1.75 ± 0.06 m), healthy and without clinical diseases or any type of orthopedic injury in the muscle skeletal system. RESULTS: The internal rotation in the right upper limb (RUL) was higher than the average strength of internal rotation in the left upper limb (LUL) (p = 0.723). The external rotation strength in RUL was lower than the average strength of external rotation in the LUL (p=0.788). No statistical difference was observed by comparing the strength values of all isometric strength tests. CONCLUSION: For the sample and methodology used to assess muscle strength, there was no statistical difference between the strength generated by the muscles of the rotator cuff of the right and left upper limbs. Experimental Study. PMID:26207091

  4. Skeletal muscle strength and endurance in recipients of lung transplants.

    PubMed

    Mathur, Sunita; Levy, Robert D; Reid, W Darlene

    2008-09-01

    Exercise limitation in recipients of lung transplant may be a result of abnormalities in the skeletal muscle. However, it is not clear whether these abnormalities are merely a reflection of the changes observed in the pretransplant condition. The purpose of this paper was to compare thigh muscle volume and composition, strength, and endurance in lung transplant recipients to people with chronic obstructive pulmonary disease (COPD). Single lung transplant recipients (n=6) and people with COPD (n=6), matched for age, sex, and BMI participated in the study. Subjects underwent MRI to determine muscle size and composition, lower extremity strength testing and an isometric endurance test of the quadriceps. Lung transplant recipients had similar muscle volumes and intramuscular fat infiltration of their thigh muscles and similar strength of the quadriceps and hamstrings to people with COPD who had not undergone transplant. However, quadriceps endurance tended to be lower in transplant recipients compared to people with COPD (15 +/- 7 seconds in transplant versus 31 +/- 12 seconds in COPD, p = 0.08). Recipients of lung transplant showed similar changes in muscle size and strength as people with COPD, however muscle endurance tended to be lower in people with lung transplants. Impairments in muscle endurance may reflect the effects of immunosuppressant medications on skeletal muscle in people with lung transplant.

  5. Coimpairments: strength and balance as predictors of severe walking disability.

    PubMed

    Rantanen, T; Guralnik, J M; Ferrucci, L; Leveille, S; Fried, L P

    1999-04-01

    Little information is available on the joint effects of multiple impairments (coimpairments) on the risk of disability. Our aim was to study the joint effects of strength and balance impairments on severe walking disability. The data are from the baseline of the Women's Health and Aging Study (WHAS), a study of moderately to severely disabled women. A total of 1,002 women aged 65 and older participated in the tests, which took place in their homes. Severe walking disability was defined as self-reported inability to walk one-quarter mile and customary walking speed in a 4-meter test of < or =0.4 m/s. Balance was measured as an ability to hold progressively more difficult stands (feet side-by-side, semitandem and tandem stands). Maximal knee extension strength was measured using a hand-held dynamometer. There were 129 women who were severely walking disabled but able to walk at least minimally. In logistic regression analysis, balance and knee extension strength were independent predictors of severe walking disability. To study the combined effects, nine groups were formed on the basis of strength tertiles by balance categories in the entire population. In the best balance category, the crude prevalences of severe walking disability were 1.2%, 4.9%, and 14.3% in the highest to lowest strength tertiles. In the middle balance category, the rates were 2.9%, 10.0%, and 45.4.1%, and in the poorest balance category 4.9%, 22.1%, and 42.6%, correspondingly. The age, body weight, and height-adjusted odds ratios (OR) showed that the risk of severe walking disability in the subgroup with best balance and strength was less than 5% of the risk in the subgroup with poorest balance and strength (OR .034, 95% confidence interval [CI] .007-.166). Correspondingly, in the subgroups with poorest strength and best balance (OR .097, 95% CI .025-.38) or poorest balance and best strength (OR .102, 95% CI .012-.866) the risk was about 10%. The age-specific estimates of prevalence of severe

  6. Changes in muscle strength in patients with statin myalgia.

    PubMed

    Panza, Gregory A; Taylor, Beth A; Roman, William; Thompson, Paul D

    2014-10-15

    Statins can produce myalgia or muscle pain, which may affect medication adherence. We measured the effects of statins on muscle strength in patients with previous statin myalgia. Leg isokinetic extension average power at 60° per second (-8.8 ± 10.5N-M, p = 0.02) and average peak torque at 60° per second (-14.0 ± 19.7N-M, p = 0.04) decreased slightly with statin use, but 8 of 10 other variables for leg strength did not change (all p >0.13). Handgrip, muscle pain, respiratory exchange ratio, and daily activity also did not change (all p >0.09). In conclusion, statin myalgia is not associated with reduced muscle strength or muscle performance. Published by Elsevier Inc.

  7. Exercise capacity, muscle strength and fatigue in sarcoidosis.

    PubMed

    Marcellis, R G J; Lenssen, A F; Elfferich, M D P; De Vries, J; Kassim, S; Foerster, K; Drent, M

    2011-09-01

    The aim of this case-control study was to investigate the prevalence of exercise intolerance, muscle weakness and fatigue in sarcoidosis patients. Additionally, we evaluated whether fatigue can be explained by exercise capacity, muscle strength or other clinical characteristics (lung function tests, radiographic stages, prednisone usage and inflammatory markers). 124 sarcoidosis patients (80 males) referred to the Maastricht University Medical Centre (Maastricht, the Netherlands) were included (mean age 46.6±10.2 yrs). Patients performed a 6-min walk test (6MWT) and handgrip force (HGF), elbow flexor muscle strength (EFMS), quadriceps peak torque (QPT) and hamstring peak torque (HPT) tests. Maximal inspiratory pressure (P(I,max)) was recorded. All patients completed the Fatigue Assessment Scale (FAS) questionnaire. The 6MWT was reduced in 45% of the population, while HGF, EFMS, QPT and HPT muscle strength were reduced in 15, 12, 27 and 18%, respectively. P(I,max) was reduced in 43% of the population. The majority of the patients (81%) reported fatigue (FAS ≥22). Patients with reduced peripheral muscle strength of the upper and/or lower extremities were more fatigued and demonstrated impaired lung functions, fat-free mass, P(I,max), 6MWT and quality of life. Fatigue was neither predicted by exercise capacity, nor by muscle strength. Besides fatigue, exercise intolerance and muscle weakness are frequent problems in sarcoidosis. We therefore recommend physical tests in the multidisciplinary management of sarcoidosis patients, even in nonfatigued patients.

  8. Quadriceps muscle strength and voluntary activation after polio.

    PubMed

    Beelen, Anita; Nollet, Frans; de Visser, Marianne; de Jong, Bareld A; Lankhorst, Gustaaf J; Sargeant, Anthony J

    2003-08-01

    Quadriceps strength, maximal anatomical cross-sectional area (CSA), maximal voluntary activation (MVA), and maximal relaxation rate (MRR) were studied in 48 subjects with a past history of polio, 26 with and 22 without postpoliomyelitis syndrome (PPS), and in 13 control subjects. It was also investigated whether, apart from CSA, MVA and MRR were determinants of muscle strength. Polio subjects had significantly less strength, CSA, and MRR in the more-affected quadriceps than control subjects. MVA was reduced in 18 polio subjects and normal in all controls. PPS subjects differed from non-PPS subjects only in that the MVA of the more-affected quadriceps was significantly lower. Both CSA and MVA were found to be associated with muscle strength. Quadriceps strength in polio subjects was dependent not only on muscle mass, but also on the ability to activate the muscles. Since impaired activation was more pronounced in PPS subjects, the new muscle weakness and functional decline in PPS may be due not only to a gradual loss of muscle fibers, but also to an increasing inability to activate the muscles.

  9. Inspiratory muscle training increases inspiratory muscle strength in patients weaning from mechanical ventilation: a systematic review.

    PubMed

    Moodie, Lisa; Reeve, Julie; Elkins, Mark

    2011-01-01

    Does inspiratory muscle training improve inspiratory muscle strength and endurance, facilitate weaning, improve survival, and reduce the rate of reintubation and tracheostomy in adults receiving mechanical ventilation? Systematic review of randomised or quasi-randomised controlled trials. Adults over 16 years of age receiving mechanical ventilation. Inspiratory muscle training versus sham or no inspiratory muscle training. Data were extracted regarding inspiratory muscle strength and endurance, the duration of unassisted breathing periods, weaning success and duration, reintubation and tracheostomy, survival, adverse effects, and length of stay. Three studies involving 150 participants were included in the review. The studies varied in time to commencement of the training, the device used, the training protocol, and the outcomes measured. Inspiratory muscle training significantly increased inspiratory muscle strength over sham or no training (weighted mean difference 8 cmH(2)O, 95% CI 6 to 9). There were no statistically significant differences between the groups in weaning success or duration, survival, reintubation, or tracheostomy. Inspiratory muscle training was found to significantly increase inspiratory muscle strength in adults undergoing mechanical ventilation. Despite data from a substantial pooled cohort, it is not yet clear whether the increase in inspiratory muscle strength leads to a shorter duration of mechanical ventilation, improved weaning success, or improved survival. Further large randomised studies are required to clarify the impact of inspiratory muscle training on patients receiving mechanical ventilation. PROSPERO CRD42011001132. Copyright © 2011 Australian Physiotherapy Association. Published by .. All rights reserved.

  10. Effects of functional training on pain, leg strength, and balance in women with fibromyalgia.

    PubMed

    Latorre Román, Pedro Ángel; Santos E Campos, María Aparecida; García-Pinillos, Felipe

    2015-01-01

    The aim of this study was to analyze the effect of 18-week functional training (FT) program consisting in two sessions a week of in-water exercise and one of on-land exercise on pain, strength, and balance in women with fibromyalgia. A sample consisting of 36 fibromyalgia patients was included in the study. The patients were allocated randomly into the experimental group (EG, n = 20), and control group (CG, n = 16). Standardized field-based fitness tests were used to assess muscle strength (30-s chair stand and handgrip strength) and agility/dynamic balance and static balance. Fibromyalgia impact and pain were analyzed by Fibromyalgia Impact Questionnaire (FIQ), tender points (TPs), visual analog scale (VAS). We observed a significant reduction in the FIQ (p = 0.042), the algometer scale of TP (p = 0.008), TP (p < 0.001), and VAS (p < 0.001) in the EG. The EG shows better results in leg strength (p < 0.001), handgrip strength (p = 0.025), agility/dynamic balance (p = 0.032) and balance (p = 0.006). An 18-week intervention consisting in two sessions of in-water exercise and one session of on-land exercise of FT reduces pain and improves functional capacity in FM patients. These results suggested that FT could play an important role in maintaining an independent lifestyle in patients with FM.

  11. Objective evaluation of muscle strength in infants with hypotonia and muscle weakness.

    PubMed

    Reus, Linda; van Vlimmeren, Leo A; Staal, J Bart; Janssen, Anjo J W M; Otten, Barto J; Pelzer, Ben J; Nijhuis-van der Sanden, Maria W G

    2013-04-01

    The clinical evaluation of an infant with motor delay, muscle weakness, and/or hypotonia would improve considerably if muscle strength could be measured objectively and normal reference values were available. The authors developed a method to measure muscle strength in infants and tested 81 typically developing infants, 6-36 months of age, and 17 infants with Prader-Willi Syndrome (PWS) aged 24 months. The inter-rater reliability of the measurement method was good (ICC=.84) and the convergent validity was confirmed by high Pearson's correlations between muscle strength, age, height, and weight (r=.79-.85). A multiple linear regression model was developed to predict muscle strength based on age, height, and weight, explaining 73% of the variance in muscle strength. In infants with PWS, muscle strength was significantly decreased. Pearson's correlations showed that infants with PWS in which muscle strength was more severely affected also had a larger motor developmental delay (r=.75). Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Muscle strength and golf performance: a critical review.

    PubMed

    Torres-Ronda, Lorena; Sánchez-Medina, Luis; González-Badillo, Juan J

    2011-01-01

    Golf has become an increasingly popular sport and a growing body of research trying to identify its main physical requirements is being published. The aim of this review was twofold: first, to examine the existing scientific literature regarding strength training and golf in healthy, non-injured, subjects; and second, to reach conclusions that could provide information on how to design more effective strength training programs to improve golf performance as well as directions for future research. Studies which analyzed the relationship between muscle strength, swing performance variables (club head speed, driving distance, ball speed) and skill (handicap, score) were reviewed. Changes in swing performance following different strength training programs were also investigated. Finally, a critical analysis about the methodologies used was carried out. The results of the reviewed studies seem to indicate that: 1) a positive relationship exists between handicap and swing performance (even though few studies have investigated this issue); 2) there is a positive correlation between skill (handicap and/or score) and muscle strength; and 3) there is a relationship between driving distance, swing speed, ball speed and muscle strength. Results suggest that training leg-hip and trunk power as well as grip strength is especially relevant for golf performance improvement. Studies that analyzed variations in swing performance following resistance-only training programs are scarce, thus it is difficult to prove whether the observed improvements are attributable to changes in strength levels. Many of the studies reviewed presented some methodological errors in their design and not all strength assessment protocols seemed appropriate. Further studies should determine muscle strength needs in relation to final swing performance, using well designed experiments and strict isoinertial assessment protocols which adequately relate to specific golf motion, age and skill level. More

  13. Muscle Strength And Golf Performance: A Critical Review

    PubMed Central

    Torres-Ronda, Lorena; Sánchez-Medina, Luis; González-Badillo, Juan J.

    2011-01-01

    Golf has become an increasingly popular sport and a growing body of research trying to identify its main physical requirements is being published. The aim of this review was twofold: first, to examine the existing scientific literature regarding strength training and golf in healthy, non-injured, subjects; and second, to reach conclusions that could provide information on how to design more effective strength training programs to improve golf performance as well as directions for future research. Studies which analyzed the relationship between muscle strength, swing performance variables (club head speed, driving distance, ball speed) and skill (handicap, score) were reviewed. Changes in swing performance following different strength training programs were also investigated. Finally, a critical analysis about the methodologies used was carried out. The results of the reviewed studies seem to indicate that: 1) a positive relationship exists between handicap and swing performance (even though few studies have investigated this issue); 2) there is a positive correlation between skill (handicap and/or score) and muscle strength; and 3) there is a relationship between driving distance, swing speed, ball speed and muscle strength. Results suggest that training leg-hip and trunk power as well as grip strength is especially relevant for golf performance improvement. Studies that analyzed variations in swing performance following resistance-only training programs are scarce, thus it is difficult to prove whether the observed improvements are attributable to changes in strength levels. Many of the studies reviewed presented some methodological errors in their design and not all strength assessment protocols seemed appropriate. Further studies should determine muscle strength needs in relation to final swing performance, using well designed experiments and strict isoinertial assessment protocols which adequately relate to specific golf motion, age and skill level. More

  14. Decreased Muscle Strength Relates to Self-Reported Stooping, Crouching, or Kneeling Difficulty in Older Adults

    PubMed Central

    Goldberg, Allon; Alexander, Neil B.

    2010-01-01

    Background Bending down and kneeling are fundamental tasks of daily living, yet nearly a quarter of older adults report having difficulty performing or being unable to perform these movements. Older adults with stooping, crouching, or kneeling (SCK) difficulty have demonstrated an increased fall risk. Strength (force-generating capacity) measures may be useful for determining both SCK difficulty and fall risk. Objective The purposes of this study were: (1) to examine muscle strength differences in older adults with and without SCK difficulty and (2) to examine the relative contributions of trunk and leg muscle strength to SCK difficulty. Design This was a cross-sectional observational study. Methods Community-dwelling older adults (age [X̅±SD]=75.5±6.0 years) with SCK difficulty (n=27) or without SCK difficulty (n=21) were tested for leg and trunk strength and functional mobility. Isometric strength at the trunk, hip, knee, and ankle also was normalized by body weight and height. Results Compared with older adults with no SCK difficulty, those with SCK difficulty had significant decreases in normalized trunk extensor, knee extensor, and ankle dorsiflexor and plantar-flexor strength. In 2 separate multivariate analyses, raw ankle plantar-flexor strength (odds ratio [OR]=0.97, 95% confidence interval [CI]=0.95–0.99) and normalized knee extensor strength (OR=0.61, 95% CI=0.44–0.82) were significantly associated with SCK difficulty. Stooping, crouching, and kneeling difficulty also correlated with measures of functional balance and falls. Limitations Although muscle groups that were key to rising from SCK were examined, there are other muscle groups that may contribute to safe SCK performance. Conclusions Decreased muscle strength, particularly when normalized for body size, predicts SCK difficulty. These data emphasize the importance of strength measurement at multiple levels in predicting self-reported functional impairment. PMID:19942678

  15. The effect of Nordic hamstring strength training on muscle architecture, stiffness, and strength.

    PubMed

    Seymore, Kayla D; Domire, Zachary J; DeVita, Paul; Rider, Patrick M; Kulas, Anthony S

    2017-05-01

    Hamstring strain injury is a frequent and serious injury in competitive and recreational sports. While Nordic hamstring (NH) eccentric strength training is an effective hamstring injury-prevention method, the protective mechanism of this exercise is not understood. Strength training increases muscle strength, but also alters muscle architecture and stiffness; all three factors may be associated with reducing muscle injuries. The purpose of this study was to examine the effects of NH eccentric strength training on hamstring muscle architecture, stiffness, and strength. Twenty healthy participants were randomly assigned to an eccentric training group or control group. Control participants performed static stretching, while experimental participants performed static stretching and NH training for 6 weeks. Pre- and post-intervention measurements included: hamstring muscle architecture and stiffness using ultrasound imaging and elastography, and maximal hamstring strength measured on a dynamometer. The experimental group, but not the control group, increased volume (131.5 vs. 145.2 cm 3 , p < 0.001) and physiological cross-sectional area (16.1 vs. 18.1 cm 2 , p = 0.032). There were no significant changes to muscle fascicle length, stiffness, or eccentric hamstring strength. The NH intervention was an effective training method for muscle hypertrophy, but, contrary to common literature findings for other modes of eccentric training, did not increase fascicle length. The data suggest that the mechanism behind NH eccentric strength training mitigating hamstring injury risk could be increasing volume rather than increasing muscle length. Future research is, therefore, warranted to determine if muscle hypertrophy induced by NH training lowers future hamstring strain injury risk.

  16. Respiratory muscle training increases respiratory muscle strength and reduces respiratory complications after stroke: a systematic review.

    PubMed

    Menezes, Kênia Kp; Nascimento, Lucas R; Ada, Louise; Polese, Janaine C; Avelino, Patrick R; Teixeira-Salmela, Luci F

    2016-07-01

    After stroke, does respiratory muscle training increase respiratory muscle strength and/or endurance? Are any benefits carried over to activity and/or participation? Does it reduce respiratory complications? Systematic review of randomised or quasi-randomised trials. Adults with respiratory muscle weakness following stroke. Respiratory muscle training aimed at increasing inspiratory and/or expiratory muscle strength. Five outcomes were of interest: respiratory muscle strength, respiratory muscle endurance, activity, participation and respiratory complications. Five trials involving 263 participants were included. The mean PEDro score was 6.4 (range 3 to 8), showing moderate methodological quality. Random-effects meta-analyses showed that respiratory muscle training increased maximal inspiratory pressure by 7 cmH2O (95% CI 1 to 14) and maximal expiratory pressure by 13 cmH2O (95% CI 1 to 25); it also decreased the risk of respiratory complications (RR 0.38, 95% CI 0.15 to 0.96) compared with no/sham respiratory intervention. Whether these effects carry over to activity and participation remains uncertain. This systematic review provided evidence that respiratory muscle training is effective after stroke. Meta-analyses based on five trials indicated that 30minutes of respiratory muscle training, five times per week, for 5 weeks can be expected to increase respiratory muscle strength in very weak individuals after stroke. In addition, respiratory muscle training is expected to reduce the risk of respiratory complications after stroke. Further studies are warranted to investigate whether the benefits are carried over to activity and participation. PROSPERO (CRD42015020683). [Menezes KKP, Nascimento LR, Ada L, Polese JC, Avelino PR, Teixeira-Salmela LF (2016) Respiratory muscle training increases respiratory muscle strength and reduces respiratory complications after stroke: a systematic review.Journal of Physiotherapy62: 138-144]. Copyright © 2016 Australian

  17. Effects on Hamstring Muscle Extensibility, Muscle Activity, and Balance of Different Stretching Techniques

    PubMed Central

    Lim, Kyoung-Il; Nam, Hyung-Chun; Jung, Kyoung-Sim

    2014-01-01

    [Purpose] The purpose of this study was to investigate the effects of two different stretching techniques on range of motion (ROM), muscle activation, and balance. [Subjects] For the present study, 48 adults with hamstring muscle tightness were recruited and randomly divided into three groups: a static stretching group (n=16), a PNF stretching group (n=16), a control group (n=16). [Methods] Both of the stretching techniques were applied to the hamstring once. Active knee extension angle, muscle activation during maximum voluntary isometric contraction (MVC), and static balance were measured before and after the application of each stretching technique. [Results] Both the static stretching and the PNF stretching groups showed significant increases in knee extension angle compared to the control group. However, there were no significant differences in muscle activation or balance between the groups. [Conclusion] Static stretching and PNF stretching techniques improved ROM without decrease in muscle activation, but neither of them exerted statistically significant effects on balance. PMID:24648633

  18. Back muscle strength, lifting, and stooped working postures.

    PubMed

    Poulsen, E; Jørgensen, K

    1971-09-01

    When lifting loads and working in a forward stooped position, the muscles of the back rather than the ligaments and bony structures of the spine should overcome the gravitational forces. Formulae, based on measurements of back muscle strength, for prediction of maximal loads to be lifted, and for the ability to sustain work in a stooped position, have been worked out and tested in practical situations. From tests with 50 male and female subjects the simplest prediction formulae for maximum loads were: max. load = 1.10 x isometric back muscle strength for men; and max. load = 0.95 x isometric back muscle strength - 8 kg for women. Some standard values for maximum lifts and permissible single and repeated lifts have been calculated for men and women separately and are given in Table 1. From tests with 65 rehabilitees it was found that the maximum isometric strength of the back muscles measured at shoulder height should exceed 2/3 of the body weight, if fatigue and/or pain in the back muscles is to be avoided during work in a standing stooped position.

  19. Normal isometric strength of rotatorcuff muscles in adults.

    PubMed

    Chezar, A; Berkovitch, Y; Haddad, M; Keren, Y; Soudry, M; Rosenberg, N

    2013-01-01

    The most prevalent disorders of the shoulder are related to the muscles of rotator cuff. In order to develop a mechanical method for the evaluation of the rotator cuff muscles, we created a database of isometric force generation by the rotator cuff muscles in normal adult population. We hypothesised the existence of variations according to age, gender and dominancy of limb. A total of 400 healthy adult volunteers were tested, classified into groups of 50 men and women for each decade of life. Maximal isometric force was measured at standardised positions for supraspinatus, infraspinatus and subscapularis muscles in both shoulders in every person. Torque of the force was calculated and normalised to lean body mass. The profiles of mean torque-time curves for each age and gender group were compared. Our data showed that men gradually gained maximal strength in the fifth decade, and showed decreased strength in the sixth. In women the maximal strength was gained in the fourth decade with gradual decline to the sixth decade of life. The dominant arm was stronger in most of the tested groups. The torque profiles of the rotator cuff muscles in men at all ages were significantly higher than that in women. We found previously unrecognised variations of rotator cuff muscles' isometric strength according to age, gender and dominancy in a normal population. The presented data may serve as a basis for the future studies for identification of the abnormal patterns of muscle isometric strength in patients with pathology of the rotator cuff muscles. Cite this article: Bone Joint Res 2013;2:214-19.

  20. Insulin resistance and muscle strength in older persons.

    PubMed

    Abbatecola, Angela M; Ferrucci, Luigi; Ceda, Gianpaolo; Russo, Cosimo R; Lauretani, Fulvio; Bandinelli, Stefania; Barbieri, Michelangela; Valenti, Giorgio; Paolisso, Giuseppe

    2005-10-01

    The functional consequences of an age-related insulin resistance (IR) state on muscle functioning are unknown. Because insulin is needed for adequate muscle function, an age-related insulin-resistant state may also be a determining factor. We evaluated the relationship between IR and handgrip muscle strength in men and women from a large population-based study (n = 968). The degree of IR was evaluated by the homeostasis model assessment (HOMA) and muscle strength was assessed using handgrip. Simple sex-stratified correlations demonstrated that, in men, body mass index-adjusted handgrip strength correlated positively with physical activity (r = 0.321; p < .001), muscle area (r = 0.420; p < .001), muscle density (r = 0.263; p = .001), plasma albumin (r = 0.156; p = .001), insulin-like growth factor-1 (r = 0.258; p < .001), calcium (r = 0.140; p = .006), and testosterone (r = 0.325; p < .001) concentrations, whereas a negative association was found for age (r = -0.659; p < .001) and myoglobin plasma levels (r = -0.164; p =.001). In women, body mass index-adjusted handgrip strength correlated positively with physical activity (r = 0.280; p < .001), muscle area (r = 0.306; p < .001), muscle density (r = 0.341; p = .001), plasma albumin (r = 0.140; p =.001), and insulin-like growth factor-1 (r = 0.300; p < .001), whereas a negative association was found for age (r = -0.563; p < .001), myoglobin levels (r = -0.164; p = .001), and IR (r = -0.130; p = .04). Sex-stratified analyses adjusted for multiple confounders showed that the relationship between IR and handgrip strength was found significant in women, whereas it was negligible and not significant in men.

  1. Comparison of traditional and recent approaches in the promotion of balance and strength in older adults.

    PubMed

    Granacher, Urs; Muehlbauer, Thomas; Zahner, Lukas; Gollhofer, Albert; Kressig, Reto W

    2011-05-01

    Demographic change in industrialized countries produced an increase in the proportion of elderly people in our society, resulting in specific healthcare challenges. One such challenge is how to effectively deal with the increased risk of sustaining a fall and fall-related injuries in old age. Deficits in postural control and muscle strength represent important intrinsic fall risk factors. Thus, adequate training regimens need to be designed and applied that have the potential to reduce the rate of falling in older adults by countering these factors. Therefore, the purpose of this review is to compare traditional and recent approaches in the promotion of balance and strength in older adults. Traditionally, balance and resistance training programmes proved to be effective in improving balance and strength, and in reducing the number of falls. Yet, it was argued that these training protocols are not specific enough to induce adaptations in neuromuscular capacities that are specifically needed in actual balance-threatening situations (e.g. abilities to recover balance and to produce force explosively). Recent studies indicated that perturbation-based or multitask balance training and power/high-velocity resistance training have the potential to improve these specific capacities because they comply with the principle of training specificity. In fact, there is evidence that these specifically tailored training programmes are more effective in improving balance recovery mechanisms and muscle power than traditional training protocols. A few pilot studies have even shown that these recently designed training protocols have an impact on the reduction of fall incidence rate in older adults. Further research is needed to confirm these results and to elucidate the underlying mechanisms responsible for the adaptive processes.

  2. Muscle strength and knee range of motion after femoral lengthening.

    PubMed

    Bhave, Anil; Shabtai, Lior; Woelber, Erik; Apelyan, Arman; Paley, Dror; Herzenberg, John E

    2017-04-01

    Background and purpose - Femoral lengthening may result in decrease in knee range of motion (ROM) and quadriceps and hamstring muscle weakness. We evaluated preoperative and postoperative knee ROM, hamstring muscle strength, and quadriceps muscle strength in a diverse group of patients undergoing femoral lengthening. We hypothesized that lengthening would not result in a significant change in knee ROM or muscle strength. Patients and methods - This prospective study of 48 patients (mean age 27 (9-60) years) compared ROM and muscle strength before and after femoral lengthening. Patient age, amount of lengthening, percent lengthening, level of osteotomy, fixation time, and method of lengthening were also evaluated regarding knee ROM and strength. The average length of follow-up was 2.9 (2.0-4.7) years. Results - Mean amount of lengthening was 5.2 (2.4-11.0) cm. The difference between preoperative and final knee flexion ROM was 2° for the overall group. Congenital shortening cases lost an average of 5% or 6° of terminal knee flexion, developmental cases lost an average of 3% or 4°, and posttraumatic cases regained all motion. The difference in quadriceps strength at 45° preoperatively and after lengthening was not statistically or clinically significant (2.7 Nm; p = 0.06). Age, amount of lengthening, percent lengthening, osteotomy level, fixation time, and lengthening method had no statistically significant influence on knee ROM or quadriceps strength at final follow-up. Interpretation - Most variables had no effect on ROM or strength, and higher age did not appear to be a limiting factor for femoral lengthening. Patients with congenital causes were most affected in terms of knee flexion.

  3. [Muscle strength of the cervical and lumbar spine in triathletes].

    PubMed

    Miltner, O; Siebert, C H; Müller-Rath, R; Kieffer, O

    2010-12-01

    better values than the reference group. Ratio of lateral left/right: In the reference group the ratio is set at 1. For triathletes, it shows an average value of 0.93. This difference is not significant. Cervical extension: The extension of the force values (1.96 ± 0.59 N/kg vs. 3.03 ± 0.24 N/kg) shows a highly significant difference from the reference group. Cervical flexion: In flexion (1.3 ± 0.42 N/kg vs. 2.17 ± 0.22 N/kg) triathletes have highly significantly lower strength values than the reference group. Flexion/extension: The triathletes did not differ significantly from the reference values (0.69 ± 0.23 and 0.72 ± 0.08). Lateral cervical spine: In comparison to the reference group (left: 1.67 ± 0.48 N/kg, right: 1.55 ± 0.46 N/kg vs. 2.36 ± 0.15 N/kg) in which there is left/right lateral flexion, there is a highly significant difference. Right lateral flexion is weaker than the left. Ratio of lateral left/right: The triathletes have a significant imbalance in the lateral flexion of the cervical spine compared to the reference group (1.07 ± 0.15 to 1). In conclusion, in the triathlon there is a specific stress that is obviously not an adequate stimulus for the muscles of the cervical spine in order to achieve a balanced musculature and the athletes should be advised to practice a preventive approach with regard to these areas. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Changes in muscle activation following balance and technique training and a season of Australian football.

    PubMed

    Donnelly, C J; Elliott, B C; Doyle, T L A; Finch, C F; Dempsey, A R; Lloyd, D G

    2015-05-01

    Determine if balance and technique training implemented adjunct to 1001 male Australian football players' training influenced the activation/strength of the muscles crossing the knee during pre-planned and unplanned sidestepping. Randomized Control Trial. Each Australian football player participated in either 28 weeks of balance and technique training or 'sham' training. Twenty-eight Australian football players (balance and technique training, n=12; 'sham' training, n=16) completed biomechanical testing pre-to-post training. Peak knee moments and directed co-contraction ratios in three degrees of freedom, as well as total muscle activation were calculated during pre-planned and unplanned sidestepping. No significant differences in muscle activation/strength were observed between the 'sham' training and balance and technique training groups. Following a season of Australian football, knee extensor (p=0.023) and semimembranosus (p=0.006) muscle activation increased during both pre-planned sidestepping and unplanned sidestepping. Following a season of Australian football, total muscle activation was 30% lower and peak valgus knee moments 80% greater (p=0.022) during unplanned sidestepping when compared with pre-planned sidestepping. When implemented in a community level training environment, balance and technique training was not effective in changing the activation of the muscles crossing the knee during sidestepping. Following a season of Australian football, players are better able to support both frontal and sagittal plane knee moments. When compared to pre-planned sidestepping, Australian football players may be at increased risk of anterior cruciate ligament injury during unplanned sidestepping in the latter half of an Australian football season. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  5. Subcutaneous immunoglobulin preserves muscle strength in chronic inflammatory demyelinating polyneuropathy.

    PubMed

    Markvardsen, L H; Harbo, T; Sindrup, S H; Christiansen, I; Andersen, H; Jakobsen, J

    2014-12-01

    Subcutaneous immunoglobulin (SCIG) is superior to placebo treatment for maintenance of muscle strength during 12 weeks in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). The present study evaluated whether SCIG preserves muscle strength for 1 year in an open-label follow-up study. Seventeen responders to intravenous immunoglobulin (IVIG) who had participated in the previous study of SCIG versus placebo in CIDP were included. After one IVIG infusion 2 weeks prior to baseline, all continued on SCIG treatment at weekly equal dosage and were evaluated after 3, 6 and 12 months. Primary end-points were changes in muscle strength evaluated by isokinetic dynamometry in four affected muscle groups and a composite score of muscle performance and function tests, including Medical Research Council (MRC) score, grip strength, 40-m walking test (40-MWT) and nine-hole peg test (9-HPT). Secondary end-points were changes of each of the listed parameters at each time point as well as an overall disability sum score (ODSS). The dose of SCIG was significantly unaltered during the follow-up period. Overall the isokinetic dynamometry value increased by 7.2% (P = 0.033) and after 3, 6 and 12 months by 5.7%, 8.2% and 6.8% (ns). The overall composite score at all time intervals and for each interval remained unchanged. Amongst the secondary parameters the MRC score increased significantly by 1.7% (P = 0.007), whereas grip strength, 40-MWT, 9-HPT and ODSS remained unchanged. SCIG preserves muscle strength and functional ability in patients with CIDP who previously responded to IVIG. SCIG should be considered as an alternative in long-term treatment of CIDP patients. © 2014 The Author(s) European Journal of Neurology © 2014 EAN.

  6. Effects of inspiratory muscle training on balance ability and abdominal muscle thickness in chronic stroke patients

    PubMed Central

    Oh, Dongha; Kim, Gayeong; Lee, Wanhee; Shin, Mary Myong Sook

    2016-01-01

    [Purpose] This study evaluated the effects of inspiratory muscle training on pulmonary function, deep abdominal muscle thickness, and balance ability in stroke patients. [Subjects] Twenty-three stroke patients were randomly allocated to an experimental (n = 11) or control group (n = 12). [Methods] The experimental group received inspiratory muscle training-based abdominal muscle strengthening with conventional physical therapy; the control group received standard abdominal muscle strengthening with conventional physical therapy. Treatment was conducted 20 minutes per day, 3 times per week for 6 weeks. Pulmonary function testing was performed using an electronic spirometer. Deep abdominal muscle thickness was measured by ultrasonography. Balance was measured using the Berg balance scale. [Results] Forced vital capacity, forced expiratory volume in 1 second, deep abdominal muscle thickness, and Berg balance scale scores were significantly improved in the experimental group than in the control group. [Conclusion] Abdominal muscle strengthening accompanied by inspiratory muscle training is recommended to improve pulmonary function in stroke patients, and may also be used as a practical adjunct to conventional physical therapy. PMID:26957739

  7. Impaired hip muscle strength in patients with femoroacetabular impingement syndrome.

    PubMed

    Kierkegaard, Signe; Mechlenburg, Inger; Lund, Bent; Søballe, Kjeld; Dalgas, Ulrik

    2017-12-01

    Patients with femoroacetabular impingement (FAI) experience hip pain as well as decreased function and lowered quality of life. The aim was to compare maximal isometric and isokinetic muscle strength (MVC) during hip flexion and extension and rate of force development (RFD) during extension between patients with FAI and a matched reference group. Secondary, the aim was to compare patient hips and subgroups defined by gender and age as well as to investigate associations between hip muscle strength and self-reported outcomes. Design Cross-sectional, comparative study Methods Sixty patients (36±9 years, 63% females) and 30 age and gender matched reference persons underwent MVC tests in an isokinetic dynamometer. During hip flexion and extension, patients' affected hip showed a strength deficit of 15-21% (p<0.001) and 10-25% (p<0.03) compared with reference MVC, respectively. The affected hip of the patients was significantly weaker than their contralateral hip. RFD was significantly decreased for both patient hips compared to the reference group (p<0.05). While age had less effect on MVC, female patients were more affected than male patients. Self-reported measures were associated with isometric hip muscle strength. Patients with FAI demonstrate decreased hip flexion and extension strength when compared to (1) reference persons and (2) their contralateral hip. There seems to be a gender specific affection which should be investigated further and addressed when planning training protocols. Furthermore, self-reported measures were associated with isometric muscle strength, which underlines the clinical importance of the reduced muscle strength. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  8. Muscle strength and endurance following lowerlimb suspension in man

    NASA Technical Reports Server (NTRS)

    Tesch, Per A.; Berg, Hans E.; Haggmark, Tom; Ohlsen, Hans; Dudley, Gary A.

    1991-01-01

    The effect of lower-limb suspension on the muscle strength and muscle endurance was investigated in six men subjected to four weeks of unilateral unloading of a lower limb (using of a harness attached to a modified shoe), followed by seven weeks of weight-bearing recovery. Results showed a decrease in the cross-sectional area (CSA) of the thigh muscle and in the average peak torque (APT) during three bouts of 30 concentric knee extensions. While the the thigh muscle CSA returned to normal after seven weeks of recovery, the APT recovery was still reduced by 11 percent, suggesting that muscle metabolic function was severely affected by unloading and was not restored by ambulation.

  9. Age at spinal cord injury determines muscle strength

    PubMed Central

    Thomas, Christine K.; Grumbles, Robert M.

    2014-01-01

    As individuals with spinal cord injury (SCI) age they report noticeable deficits in muscle strength, endurance and functional capacity when performing everyday tasks. These changes begin at ~45 years. Here we present a cross-sectional analysis of paralyzed thenar muscle and motor unit contractile properties in two datasets obtained from different subjects who sustained a cervical SCI at different ages (≤46 years) in relation to data from uninjured age-matched individuals. First, completely paralyzed thenar muscles were weaker when C6 SCI occurred at an older age. Muscles were also significantly weaker if the injury was closer to the thenar motor pools (C6 vs. C4). More muscles were strong (>50% uninjured) in those injured at a younger (≤25 years) vs. young age (>25 years), irrespective of SCI level. There was a reduction in motor unit numbers in all muscles tested. In each C6 SCI, only ~30 units survived vs. 144 units in uninjured subjects. Since intact axons only sprout 4–6 fold, the limits for muscle reinnervation have largely been met in these young individuals. Thus, any further reduction in motor unit numbers with time after these injuries will likely result in chronic denervation, and may explain the late-onset muscle weakness routinely described by people with SCI. In a second dataset, paralyzed thenar motor units were more fatigable than uninjured units. This gap widened with age and will reduce functional reserve. Force declines were not due to electromyographic decrements in either group so the site of failure was beyond excitation of the muscle membrane. Together, these results suggest that age at SCI is an important determinant of long-term muscle strength, and fatigability, both of which influence functional capacity. PMID:24478643

  10. The Relationship between Walk Distance and Muscle Strength, Muscle Pain in Visually Disabled People

    ERIC Educational Resources Information Center

    Akyol, Betül

    2018-01-01

    The purpose of this study is to examine the relationship between six-minute walk test and muscle pain, muscle strength in visually disabled people. The study includes 50 visually disabled people, aged between 17, 21 ± 5,3. Participants were classified into three categories according to their degree of vision (B1, B2, B3). All participants were…

  11. Quantitative muscle ultrasound and quadriceps strength in patients with post-polio syndrome.

    PubMed

    Bickerstaffe, Alice; Beelen, Anita; Zwarts, Machiel J; Nollet, Frans; van Dijk, Johannes P

    2015-01-01

    We investigated whether muscle ultrasound can distinguish muscles affected by post-polio syndrome (PPS) from healthy muscles and whether severity of ultrasound abnormalities is associated with muscle strength. Echo intensity, muscle thickness, and isometric strength of the quadriceps muscles were measured in 48 patients with PPS and 12 healthy controls. Patients with PPS had significantly higher echo intensity and lower muscle thickness than healthy controls. In patients, both echo intensity and muscle thickness were associated independently with muscle strength. A combined measure of echo intensity and muscle thickness was more strongly related to muscle strength than either parameter alone. Quantitative ultrasound distinguishes healthy muscles from those affected by PPS, and measures of muscle quality and quantity are associated with muscle strength. Hence, ultrasound could be a useful tool for assessing disease severity and monitoring changes resulting from disease progression or clinical intervention in patients with PPS. © 2014 Wiley Periodicals, Inc.

  12. Gait, Balance, Leg Strength, and Sprint Speed After Bedrest with LBNP Exercise

    NASA Technical Reports Server (NTRS)

    Boda, Wanda L.; Watenbaugh, D. E.; Ballard, R. E.; Fortney, S. M.; Ertl, A. C.; Lee, S. M. C.; William, J. M.; Hargens, Alan R.

    1997-01-01

    Microgravity and bedrest (BR) result in similar physiological decrements such as loss of muscle mass, muscle strength and balance. Previous studies analyzing exercise within lower body negative pressure (LBNP) have found that gait is similar in LBNP on a vertical treadmill and overground exercise on a horizontal treadmill. Since treadmill exercise is known to increase muscular strength and endurance, we tested the hypothesis that LBNP exercise on a vertical treadmill would prevent or attenuate many of the physical decrements which occur during bedrest. Based on our positive results from diverse tests of post-BR function, we believe that exercise within LBNP is worth pursuing as a countermeasure for reducing the physical deterioration that occurs during bedrest and microgravity.

  13. Effect of muscle length on strength and dexterity after stroke.

    PubMed

    Ada, L; Canning, C; Dwyer, T

    2000-02-01

    The effect of muscle length on strength and dexterity after stroke was investigated. The aim was to determine if poor function at a particular muscle length could be attributed solely to differential weakness at this joint angle or whether an additional problem of differential dexterity exists. This descriptive research study measured elbow flexor and extensor strength as well as dexterity at three elbow joint angles: 30 degrees , 60 degrees and 90 degrees flexion. Dexterity was measured independently of strength. Fifteen (seven female, eight male) chronic stroke patients (mean age 67 years) who could actively flex and extend their affected elbow participated. Ten neurologically normal control subjects (mean age 67 years) acted as controls. Strength was measured as peak elbow flexor and extensor torque at three angles; and dexterity was measured as coherence for slow and fast tracking also at three angles. Dexterity was not affected by muscle length but strength was and this finding was the same for both stroke and controls. While the magnitude of the torque-angle curves was not significantly different between stroke and controls, the shape of torque-angle curves was altered after stroke so that both the elbow flexors (p < 0.05) and extensors (p < 0.05) tested weaker in the testing position where they were shortest. Since there was no differential loss of dexterity, it appears that differential loss of strength, especially in the shortened range, may explain the clinical observation of poorer function at one muscle length than another after stroke. Specific training to strengthen the muscles in these ranges is therefore of clinical importance for rehabilitation.

  14. Muscle strength and body composition are clinical indicators of osteoporosis.

    PubMed

    Rikkonen, Toni; Sirola, Joonas; Salovaara, Kari; Tuppurainen, Marjo; Jurvelin, Jukka S; Honkanen, Risto; Kröger, Heikki

    2012-08-01

    We examined the role of muscle strength, lean tissue distribution, and overall body composition as indicators of osteoporosis (OP) in a pooled sample of 979 Finnish postmenopausal women (mean age 68.1 years) from the Kuopio Osteoporosis Risk Factor and Prevention study. Bone mineral density (BMD) at the femoral neck (FN) and total body composition were assessed by dual-energy X-ray absorptiometry scans. The women (n = 979) were divided into three groups according to WHO criteria, based on FN BMD T score: normal (n = 474), osteopenia (n = 468), and OP (n = 37). Soft tissue proportions, fat mass index (FMI, fat/height²), lean mass index (LMI, lean/height²), and appendicular skeletal muscle mass (ASM, (arms + legs)/height²) were calculated. Handgrip and knee extension strength measurements were made. OP subjects had significantly smaller LMI (p = 0.001), ASM (p = 0.001), grip strength (p < 0.0001), and knee extension strength (p < 0.05) but not FMI (p > 0.05) compared to other subjects. Grip and knee extension strength were 19 and 16 % weaker in OP women compared to others, respectively. The area under the receiver operating characteristic curve was 69 % for grip and 71 % for knee extension strength. In tissue proportions only LMI showed predictive power (63 %, p = 0.016). An overall linear association of LMI (R² = 0.007, p = 0.01) and FMI (R² = 0.028, p < 0.001) with FN BMD remained significant. In the multivariate model, after adjusting for age, grip strength, leg extension strength, FMI, LMI, number of medications, alcohol consumption, current smoking, dietary calcium intake, and hormone therapy, grip strength (adjusted OR = 0.899, 95 % CI 0.84-0.97, p < 0.01), leg extension strength (OR = 0.998, 95 % CI 0.99-1, p < 0.05), and years of hormone therapy (OR = 0.905, 95 % CI 0.82-1, p < 0.05) remained as significant determinants of OP. Muscle strength tests, especially grip strength, serve as an independent and useful tool for postmenopausal OP risk assessment

  15. Diagnostic methods to assess inspiratory and expiratory muscle strength*

    PubMed Central

    Caruso, Pedro; de Albuquerque, André Luis Pereira; Santana, Pauliane Vieira; Cardenas, Leticia Zumpano; Ferreira, Jeferson George; Prina, Elena; Trevizan, Patrícia Fernandes; Pereira, Mayra Caleffi; Iamonti, Vinicius; Pletsch, Renata; Macchione, Marcelo Ceneviva; Carvalho, Carlos Roberto Ribeiro

    2015-01-01

    Impairment of (inspiratory and expiratory) respiratory muscles is a common clinical finding, not only in patients with neuromuscular disease but also in patients with primary disease of the lung parenchyma or airways. Although such impairment is common, its recognition is usually delayed because its signs and symptoms are nonspecific and late. This delayed recognition, or even the lack thereof, occurs because the diagnostic tests used in the assessment of respiratory muscle strength are not widely known and available. There are various methods of assessing respiratory muscle strength during the inspiratory and expiratory phases. These methods are divided into two categories: volitional tests (which require patient understanding and cooperation); and non-volitional tests. Volitional tests, such as those that measure maximal inspiratory and expiratory pressures, are the most commonly used because they are readily available. Non-volitional tests depend on magnetic stimulation of the phrenic nerve accompanied by the measurement of inspiratory mouth pressure, inspiratory esophageal pressure, or inspiratory transdiaphragmatic pressure. Another method that has come to be widely used is ultrasound imaging of the diaphragm. We believe that pulmonologists involved in the care of patients with respiratory diseases should be familiar with the tests used in order to assess respiratory muscle function.Therefore, the aim of the present article is to describe the advantages, disadvantages, procedures, and clinical applicability of the main tests used in the assessment of respiratory muscle strength. PMID:25972965

  16. Myotonometry as a Surrogate Measure of Muscle Strength

    NASA Technical Reports Server (NTRS)

    Ang, B. S.; Feeback, D. L.; Leonard, C. T.; Sykes, J.; Kruger, E.; Clarke, M. S. F.

    2007-01-01

    Space flight-induced muscle atrophy/neuromuscular degradation and the consequent decrements in crew-member performance are of increasing concern as mission duration lengthens, and planetary exploration after extended space flight is planned. Pre- to post-flight strength measures have demonstrated that specific countermeasures, such as resistive exercise, are effective at countering microgravity-induced muscle atrophy and preventing decrements in muscle strength. However, in-flight assessment/monitoring of exercise countermeasure effectiveness will be essential during exploration class missions due to their duration. The ability to modify an exercise countermeasure prescription based on such real-time information will allow each individual crew member to perform the optimal amount and type of exercise countermeasure to maintain performance. In addition, such measures can be used to determine if a crew member is physically capable of performing a particular mission-related task during exploration class missions. The challenges faced in acquiring such data are those common to all space operations, namely the requirement for light-weight, low power, mechanically reliable technologies that make valid measurements in microgravity, in this case of muscle strength/neuromuscular function. Here we describe a simple, light-weight, low power, non-invasive device, known as the Myotonometer, that measures tissue stiffness as an indirect measure of muscle contractile state and muscle force production. Repeat myotonometer measurements made at the same location on the surface of the rectis femoris muscle (as determined using a 3D locator device, SEM plus or minus 0.34 mm) were shown to be reproducible over time at both maximal voluntary contraction (MVC) and at rest in a total of 17 sedentary subjects assessed three times over a period of seven days. In addition, graded voluntary isometric force production (i.e. 20%, 40%, 60%, 80% & 100% of MVC) during knee extension was shown to

  17. Strength and muscle mass loss with aging process. Age and strength loss.

    PubMed

    Keller, Karsten; Engelhardt, Martin

    2013-10-01

    aging process is associated with changes in muscle mass and strength with decline of muscle strength after the 30(th) life year. The aim of this study was to investigate these changes in muscle mass and strength. for this analysis 26 participants were subdivided in two groups. Group 1 comprises participants aged <40 years (n=14), group 2 those >40 years (n=12). We assessed anthropometrics, range of motions, leg circumferences and isometric strength values of the knee joints. besides comparable anthropometrics, circumferences and strength were higher in group 1 than in group 2. Circumference of upper leg (20 cm above knee articular space) showed for right leg a trend to a significant (median: 54.45 cm (1(st) quartile: 49.35/3(rd) quartile: 57.78) vs 49.80 cm (49.50/50.75), p=0.0526) and for left leg a significant 54.30 cm (49.28/58.13) vs 49.50 cm (48.00/52.53), p=0.0356) larger circumference in group 1. Isometric strength was in 60° knee flexion significantly higher in group 1 than in group 2 for right (729.88N (561.47/862.13) vs 456.92N (304.67/560.12), p=0.00448) and left leg (702.49N (581.36/983.87) vs 528.49N (332.95/648.58), p=0.0234). aging process leads to distinct muscle mass and strength loss. Muscle strength declines from people aged <40 years to those >40 years between 16.6% and 40.9%.

  18. A randomised controlled trial among cleaners--effects on strength, balance and kinesiophobia.

    PubMed

    Jørgensen, Marie Birk; Ektor-Andersen, John; Sjøgaard, Gisela; Holtermann, Andreas; Søgaard, Karen

    2011-10-10

    Cleaners constitute a job group with poor health and low socioeconomic resources. Therefore, there is a great need for scientifically documented health promoting initiatives for cleaners. However, both workplace initiatives and high quality intervention studies are lacking. The aim of this study was to evaluate the effects of a 3-month workplace trial with interventions to improve physical or cognitive behavioural resources among cleaners. A cluster randomised controlled trial was conducted among 294 female cleaners from 9 workplaces. The participants were allocated to three groups: Physical coordination training (PCT, n = 95), Cognitive behavioural theory-based training (CBTr, n = 99) and Reference group (REF, n = 100). Interventions were conducted during work hours for an average of 1 hour/week. Muscle strength was measured by maximal voluntary contractions in trunk/extension, and shoulder abduction/elevation. Postural balance was measured on a force platform. Kinesiophobia was measured with Tampa Scale for Kinesiophobia. Test and questionnaires were completed at baseline and at 3-month follow-up and analyses followed the intention-to-treat (ITT) principle with last observation carried forward in case of missing data at follow-up. Reports and analyses are given on true observations as well. ITT-analyses revealed that PCT improved strength of the trunk (p < .05) and postural balance (p < .05) compared to CBTr and REF. Based on true observations the strength and balance improvements corresponded to ~20% and ~16%, respectively. ITT-analyses showed that CBTr reduced kinesiophobia compared to PCT and REF (p < .05). Based on true observations, the improvement corresponded to a ~16% improvement. This workplace-based intervention study including PCT and CBTr among cleaners improved strength and postural balance from PCT, and kinesiophobia from CBTr. The improved strength, postural balance and kinesiophobia may improve the cleaners' tolerance for high physical work

  19. Research on measurement of aviation magneto ignition strength and balance

    NASA Astrophysics Data System (ADS)

    Gao, Feng; He, Zhixiang; Zhang, Dingpeng

    2017-12-01

    Aviation magneto ignition system failure accounted for two-thirds of the total fault aviation piston engine and above. At present the method used for this failure diagnosis is often depended on the visual inspections in the civil aviation maintenance field. Due to human factors, the visual inspections cannot provide ignition intensity value and ignition equilibrium deviation value among the different spark plugs in the different cylinder of aviation piston engine. So air magneto ignition strength and balance testing has become an aviation piston engine maintenance technical problem needed to resolve. In this paper, the ultraviolet sensor with detection wavelength of 185~260nm and driving voltage of 320V DC is used as the core of ultraviolet detection to detect the ignition intensity of Aviation magneto ignition system and the balance deviation of the ignition intensity of each cylinder. The experimental results show that the rotational speed within the range 0 to 3500 RPM test error less than 0.34%, ignition strength analysis and calculation error is less than 0.13%, and measured the visual inspection is hard to distinguish between high voltage wire leakage failure of deviation value of 200 pulse ignition strength balance/Sec. The method to detect aviation piston engine maintenance of magneto ignition system fault has a certain reference value.

  20. The value of multiple tests of respiratory muscle strength

    PubMed Central

    Steier, Joerg; Kaul, Sunny; Seymour, John; Jolley, Caroline; Rafferty, Gerrard; Man, William; Luo, Yuan M; Roughton, Michael; Polkey, Michael I; Moxham, John

    2007-01-01

    Background Respiratory muscle weakness is an important clinical problem. Tests of varying complexity and invasiveness are available to assess respiratory muscle strength. The relative precision of different tests in the detection of weakness is less clear, as is the value of multiple tests. Methods The respiratory muscle function tests of clinical referrals who had multiple tests assessed in our laboratories over a 6‐year period were analysed. Thresholds for weakness for each test were determined from published and in‐house laboratory data. The patients were divided into three groups: those who had all relevant measurements of global inspiratory muscle strength (group A, n = 182), those with full assessment of diaphragm strength (group B, n = 264) and those for whom expiratory muscle strength was fully evaluated (group C, n = 60). The diagnostic outcome of each inspiratory, diaphragm and expiratory muscle test, both singly and in combination, was studied and the impact of using more than one test to detect weakness was calculated. Results The clinical referrals were primarily for the evaluation of neuromuscular diseases and dyspnoea of unknown cause. A low maximal inspiratory mouth pressure (Pimax) was recorded in 40.1% of referrals in group A, while a low sniff nasal pressure (Sniff Pnasal) was recorded in 41.8% and a low sniff oesophageal pressure (Sniff Poes) in 37.9%. When assessing inspiratory strength with the combination of all three tests, 29.6% of patients had weakness. Using the two non‐invasive tests (Pimax and Sniff Pnasal) in combination, a similar result was obtained (low in 32.4%). Combining Sniff Pdi (low in 68.2%) and Twitch Pdi (low in 67.4%) reduced the diagnoses of patients with diaphragm weakness to 55.3% in group B. 38.3% of the patients in group C had expiratory muscle weakness as measured by maximum expiratory pressure (Pemax) compared with 36.7% when weakness was diagnosed by cough gastric pressure (Pgas), and 28.3% when

  1. Muscle strength in breast cancer patients receiving different treatment regimes

    PubMed Central

    Klassen, Oliver; Schmidt, Martina E.; Ulrich, Cornelia M.; Schneeweiss, Andreas; Potthoff, Karin; Steindorf, Karen

    2016-01-01

    Abstract Background Muscle dysfunction and sarcopenia have been associated with poor performance status, an increased mortality risk, and greater side effects in oncologic patients. However, little is known about how performance is affected by cancer therapy. We investigated muscle strength in breast cancer patients in different adjuvant treatment settings and also compared it with data from healthy individuals. Methods Breast cancer patients (N = 255) from two randomized controlled exercise trials, staged 0–III and aged 54.4 ± 9.4 years, were categorized into four groups according to their treatment status. In a cross‐sectional design, muscle function was assessed bilaterally by isokinetic dynamometry (0°, 60°, 180°/s) as maximal voluntary isometric contraction (MVIC) and maximal isokinetic peak torque (MIPT) in shoulder rotators and knee flexors and extensors. Additionally, muscular fatigue index (FI%) and shoulder flexibility were evaluated. Healthy women (N = 26), aged 53.3 ± 9.8 years, were tested using the same method. Analysis of covariance was used to estimate the impact of different cancer treatments on skeletal muscle function with adjustment for various clinical and socio‐demographic factors. Results Consistently, lower muscle strength was measured in shoulder and knee strength in patients after chemotherapy. On average, patients had up to 25% lower strength in lower extremities and 12–16% in upper extremities in MVIC and MIPT during cancer treatment compared with healthy women. No substantial difference between patient groups in shoulder strength, but significantly lower shoulder flexibility in patients with radical mastectomy was measured. Chemotherapy‐treated patients had consistently higher FI%. No serious adverse events were reported. Conclusions Breast cancer patients showed markedly impaired muscle strength and joint dysfunctions before and after anticancer treatment. The significant differences between patients

  2. Strength Training for Skeletal Muscle Endurance after Stroke

    PubMed Central

    Ivey, Frederick M.; Prior, Steven J.; Hafer-Macko, Charlene E.; Katzel, Leslie I.; Macko, Richard F.; Ryan, Alice S.

    2018-01-01

    Background and Purpose Initial studies support the use of strength training (ST) as a safe and effective intervention after stroke. Our previous work shows that relatively aggressive, higher intensity ST translates into large effect sizes for paretic and non-paretic leg muscle volume, myostatin expression, and maximum strength post-stroke. An unanswered question pertains to how our unique ST model for stroke impacts skeletal muscle endurance (SME). Thus, we now report on ST-induced adaptation in the ability to sustain isotonic muscle contraction. Methods Following screening and baseline testing, hemiparetic stroke participants were randomized to either ST or an attention-matched stretch control group (SC). Those in the ST group trained each leg individually to muscle failure (20 repetition sets, 3× per week for 3 months) on each of three pneumatic resistance machines (leg press, leg extension, and leg curl). Our primary outcome measure was SME, quantified as the number of submaximal weight leg press repetitions possible at a specified cadence. The secondary measures included one-repetition maximum strength, 6-minute walk distance (6MWD), 10-meter walk speeds, and peak aerobic capacity (VO2 peak). Results ST participants (N = 14) had significantly greater SME gains compared with SC participants (N = 16) in both the paretic (178% versus 12%, P < .01) and non-paretic legs (161% versus 12%, P < .01). These gains were accompanied by group differences for 6MWD (P < .05) and VO2 peak (P < .05). Conclusion Our ST regimen had a large impact on the capacity to sustain submaximal muscle contraction, a metric that may carry more practical significance for stroke than the often reported measures of maximum strength. PMID:27865696

  3. Muscle strength is associated with vitamin D receptor gene variants.

    PubMed

    Bozsodi, Arpad; Boja, Sara; Szilagyi, Agnes; Somhegyi, Annamaria; Varga, Peter Pal; Lazary, Aron

    2016-11-01

    Vitamin D receptor (VDR) is an important candidate gene in muscle function. Scientific reports on the effect of its genetic variants on muscle strength are contradictory likely due to the inconsistent study designs. Hand grip strength (HGS) is a highly heritable phenotype of muscle strength but only limited studies are available on its genetic background. Association between VDR polymorphisms and HGS has been poorly investigated and previous reports are conflicting. We studied the effect of VDR gene variants on HGS in a sample of 706 schoolchildren. Genomic DNA was extracted from saliva samples and six candidate single nucleotide polymorphisms (SNPs) across the VDR gene were genotyped with Sequenom MassARRAY technique. HGS was measured with a digital dynamometer in both hands. Single marker and haplotype associations were adjusted for demographic parameters. Three SNPs, rs4516035 (A1012G; p = 0.009), rs1544410 (BsmI; p = 0.010), and rs731236 (TaqI; p = 0.038) and a 3' UTR haploblock constructed by three SNPs (Bsml-Taq1-rs10783215; p < 0.005) showed significantly associations with HGS of the dominant hand. In the non-dominant hand, the effects of the A1012G (p = 0.034) and the 3' UTR haploblock (p < 0.01) on HGS were also significant. Since the promoter SNP (A10112G) and the 3' UTR haplotype were proved to be associated with the expression and the stability of the VDR mRNA in earlier studies, VDR variants can be supposed to have a direct effect on muscle strength. The individual genetic patterns can also explain the inconsistency of the previously published clinical results on the association between vitamin D and muscle function. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2031-2037, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  4. Bone mineral density, muscle strength, and recreational exercise in men

    NASA Technical Reports Server (NTRS)

    Snow-Harter, C.; Whalen, R.; Myburgh, K.; Arnaud, S.; Marcus, R.

    1992-01-01

    Muscle strength has been shown to predict bone mineral density (BMD) in women. We examined this relationship in 50 healthy men who ranged in age from 28 to 51 years (average 38.3 years). BMD of the lumbar spine, proximal femur, whole body, and tibia were measured by dual-energy x-ray absorptiometry (Hologic QDR 1000W). Dynamic strength using one repetition maximum was assessed for the biceps, quadriceps, and back extensors and for the hip abductors, adductors, and flexors. Isometric grip strength was measured by dynamometry. Daily walking mileage was assessed by 9 week stepmeter records and kinematic analysis of video filming. Subjects were designated as exercisers and nonexercisers. Exercisers participated in recreational exercise at least two times each week. The results demonstrated that BMD at all sites correlated with back and biceps strength (p < 0.01 to p = 0.0001). Body weight correlated with tibia and whole-body BMD (p < 0.001); age negatively correlated with Ward's triangle BMD (p < 0.01). In stepwise multiple regressions, back strength was the only independent predictor of spine and femoral neck density (R2 = 0.27). Further, back strength was the most robust predictor of BMD at the trochanter, Ward's triangle, whole body, and tibia, although biceps strength, age, body weight, and leg strength contributed significantly to BMD at these skeletal sites, accounting for 35-52% of the variance in BMD. Exercisers and nonexercisers were similar for walking (3.97 versus 3.94 miles/day), age (37.8 versus 38.5) years, and weight (80.0 versus 77.7 kg). However, BMD and muscle strength were significantly greater in exercises than in nonexercisers.(ABSTRACT TRUNCATED AT 250 WORDS).

  5. Reliability and relationships among handgrip strength, leg extensor strength and power, and balance in older men.

    PubMed

    Jenkins, Nathaniel D M; Buckner, Samuel L; Bergstrom, Haley C; Cochrane, Kristen C; Goldsmith, Jacob A; Housh, Terry J; Johnson, Glen O; Schmidt, Richard J; Cramer, Joel T

    2014-10-01

    To quantify the reliability of isometric leg extension torque (LEMVC), rate of torque development (LERTD), isometric handgrip force (HGMVC) and RFD (HGRFD), isokinetic leg extension torque and power at 1.05rad·s(-1) and 3.14rad·s(-1); and explore relationships among strength, power, and balance in older men. Sixteen older men completed 3 isometric handgrips, 3 isometric leg extensions, and 3 isokinetic leg extensions at 1.05rad·s(-1) and 3.14rad·s(-1) during two visits. Intraclass correlation coefficients (ICCs), ICC confidence intervals (95% CI), coefficients of variation (CVs), and Pearson correlation coefficients were calculated. LERTD demonstrated no reliability. The CVs for LERTD and HGRFD were ≤23.26%. HGMVC wasn't related to leg extension torque or power, or balance (r=0.14-0.47; p>0.05). However, moderate to strong relationships were found among isokinetic leg extension torque at 1.05rad·s(-1) and 3.14rad·s(-1), leg extension mean power at 1.05rad·s(-1), and functional reach (r=0.51-0.95; p≤0.05). LERTD and HGRFD weren't reliable and shouldn't be used as outcome variables in older men. Handgrip strength may not be an appropriate surrogate for lower body strength, power, or balance. Instead, perhaps handgrip strength should only be used to describe upper body strength or functionality, which may compliment isokinetic assessments of lower body strength, which were reliable and related to balance. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Correlation of the Y-Balance Test with Lower-limb Strength of Adult Women

    PubMed Central

    Lee, Dong-Kyu; Kim, Gyoung-Mo; Ha, Sung-Min; Oh, Jae-Seop

    2014-01-01

    [Purpose] The purpose of this study was to elucidate the relationship between Y-balance test (YBT) distance and the lower-limb strength of adult women. [Subjects] Forty women aged 45 to 80 years volunteered for this study. [Methods] The participants were tested for maximal muscle strength of the lower limbs (hip extensors, hip flexors, hip abductors, knee extensors, knee flexors, and ankle dorsiflexors) and YBT distances in the anterior, posteromedial, and posterolateral directions. Pearson’s correlation coefficient was used to quantify the linear relationships between YBT distances and lower-limb strength. [Results] Hip extensor and knee flexor strength were positively correlated with YBT anterior distance. Hip extensor, hip abductor, and knee flexor strength were positively correlated with the YBT posteromedial distance. Hip extensor and knee flexor strength were positively correlated with YBT posterolateral distance. [Conclusion] There was a weak correlation between lower-limb strength (hip extensors, hip abductors, and knee flexors) and dynamic postural control as measured by the YBT. PMID:24926122

  7. Intra-rater reliability of hallux flexor strength measures using the Nintendo Wii Balance Board.

    PubMed

    Quek, June; Treleaven, Julia; Brauer, Sandra G; O'Leary, Shaun; Clark, Ross A

    2015-01-01

    The purpose of this study was to investigate the intra-rater reliability of a new method in combination with the Nintendo Wii Balance Board (NWBB) to measure the strength of hallux flexor muscle. Thirty healthy individuals (age: 34.9 ± 12.9 years, height: 170.4 ± 10.5 cm, weight: 69.3 ± 15.3 kg, female = 15) participated. Repeated testing was completed within 7 days. Participants performed strength testing in sitting using a wooden platform in combination with the NWBB. This new method was set up to selectively recruit an intrinsic muscle of the foot, specifically the flexor hallucis brevis muscle. Statistical analysis was performed using intra-class coefficients and ordinary least product analysis. To estimate measurement error, standard error of measurement (SEM), minimal detectable change (MDC) and percentage error were calculated. Results indicate excellent intra-rater reliability (ICC = 0.982, CI = 0.96-0.99) with an absence of systematic bias. SEM, MDC and percentage error value were 0.5, 1.4 and 12 % respectively. This study demonstrates that a new method in combination with the NWBB application is reliable to measure hallux flexor strength and has potential to be used for future research and clinical application.

  8. Experimental neck muscle pain impairs standing balance in humans.

    PubMed

    Vuillerme, Nicolas; Pinsault, Nicolas

    2009-02-01

    Impaired postural control has been reported in patients with chronic neck pain of both traumatic and non-traumatic etiologies, but whether painful stimulation of neck muscle per se can affect balance control during quiet standing in humans remains unclear. The purpose of the present experiment was thus to investigate the effect of experimental neck muscle pain on standing balance in young healthy adults. To achieve this goal, 16 male university students were asked to stand upright as still as possible on a force platform with their eyes closed in two conditions of No pain and Pain of the neck muscles elicited by experimental painful electrical stimulation. Postural control and postural performance were assessed by the displacements of the center of foot pressure (CoP) and of the center of mass (CoM), respectively. The results showed increased CoP and CoM displacements variance, range, mean velocity, and mean and median frequencies in the Pain relative to the No pain condition. The present findings emphasize the destabilizing effect of experimental neck muscle pain per se, and more largely stress the importance of intact neck neuromuscular function on standing balance.

  9. Trunk Muscle Attributes are Associated with Balance and Mobility in Older Adults: A Pilot Study

    PubMed Central

    Suri, Pradeep; Kiely, Dan K.; Leveille, Suzanne G.; Frontera, Walter R.; Bean, Jonathan. F.

    2010-01-01

    Objective To determine if trunk muscle attributes are associated with balance and mobility performance among mobility-limited older adults. Design Cross-sectional analysis of data from a randomized clinical trial. Setting Outpatient rehabilitation research center. Participants Community-dwelling older adults (N=70; mean age 75.9 y) with mobility limitations as defined by the Short Physical Performance Battery (SPPB). Methods Independent variables included physiologic measures of trunk extension strength, trunk flexion strength, trunk extension endurance, trunk extension endurance and leg press strength. All measures were well tolerated by the study subjects without the occurrence of any associated injuries or adverse events. The association of each physiologic measure with each outcome was examined, using separate multivariate models to calculate the partial variance (R2) of each trunk and extremity measure. Main Outcome Measurements Balance measured by the Berg Balance Scale (BBS) and Unipedal Stance Test (UST), and mobility performance as measured by the SPPB. Results Trunk extension endurance (partial R2=.14, p=.02), and leg press strength (partial R2=.14, p=.003) accounted for the greatest amount of the variance in SPPB performance. Trunk extension endurance (partial R2=.17, p=.007), accounted for the greatest amount of the variance in BBS performance. Trunk extension strength (R2=.09, p=.03), accounted for the greatest amount of the variance in UST performance. The variance explained by trunk extension endurance equaled or exceeded the variance explained by limb strength across all three performance outcomes. Conclusions Trunk endurance and strength can be safely measured in mobility-limited older adults, and are associated with both balance and mobility performance. Trunk endurance and trunk strength are physiologic attributes worthy of targeting in the rehabilitative care of mobility-limited older adults. PMID:19854420

  10. Trunk muscle attributes are associated with balance and mobility in older adults: a pilot study.

    PubMed

    Suri, Pradeep; Kiely, Dan K; Leveille, Suzanne G; Frontera, Walter R; Bean, Jonathan F

    2009-10-01

    To determine whether trunk muscle attributes are associated with balance and mobility performance among mobility-limited older adults. Cross-sectional analysis of data from a randomized clinical trial. Outpatient rehabilitation research center. Community-dwelling older adults (N = 70; mean age 75.9 years) with mobility limitations as defined by the Short Physical Performance Battery (SPPB). Independent variables included physiologic measures of trunk extension strength, trunk flexion strength, trunk extension endurance, trunk extension endurance, and leg press strength. All measures were well tolerated by the study subjects without the occurrence of any associated injuries or adverse events. The association of each physiologic measure with each outcome was examined by the use of separate multivariate models to calculate the partial variance (R(2)) of each trunk and extremity measure. Balance measured by the Berg Balance Scale and Unipedal Stance Test and mobility performance as measured by the SPPB. Trunk extension endurance (partial R(2) = .14, P = .02), and leg press strength (partial R(2) = .14, P = .003) accounted for the greatest amount of the variance in SPPB performance. Trunk extension endurance (partial R(2) = .17, P = .007), accounted for the greatest amount of the variance in BBS performance. Trunk extension strength (R(2) = .09, P = .03), accounted for the greatest amount of the variance in UST performance. The variance explained by trunk extension endurance equaled or exceeded the variance explained by limb strength across all three performance outcomes. Trunk endurance and strength can be safely measured in mobility-limited older adults and are associated with both balance and mobility performance. Trunk endurance and trunk strength are physiologic attributes worthy of targeting in the rehabilitative care of mobility-limited older adults.

  11. Muscle Strength and Flexibility without and with Visual Impairments Judoka's

    ERIC Educational Resources Information Center

    Karakoc, Onder

    2016-01-01

    The aim of this study was to examine muscle strength and flexibility of judoka with and without visual impairments. A total of 32 male national judoka volunteered to participate in this study. There were 20 male judoka without visual impairments (mean ± SD; age: 19.20 ± 5.76 years, body weight: 66.45 ± 11.09 kg, height: 169.60 ± 7.98 cm, sport…

  12. Circuit strength training improves muscle strength, functional performance and anthropometric indicators in sedentary elderly women.

    PubMed

    Mazini Filho, Mauro L; Aidar, Felipe J; Gama de Matos, Dihogo; Costa Moreira, Osvaldo; Patrocínio de Oliveira, Cláudia E; de Oliveira Venturini, Gabriela R; Magalhães Curty, Victor; Menezes Touguinha, Henrique; Caputo Ferreira, Maria E

    2017-04-26

    This study aimed to investigate the effects of circuit strength training on the muscle strength, functional autonomy and anthropometric indicators of the elderly. Were included 65 women divided in two groups: strength training (TG, n= 34) and control group (CG, n = 31). The strength-training group was subjected to a circuit shaped training program, three days per week, for a period of 12 weeks. In each training session, the circuit was repeated three times. In each circuit, all exercises wereperformed once, with 8 to 12 repetitions per exercise, with 30-seconds intervals between each exercise. TG showed significantly changes in body composition post 12 weeks, as decreases in body weight (Δ -1.5±1.8 kg) and BMI (Δ-0.57 ±0.74 kg/m²), and decreases in abdominal (Δ -3±1.61 cm), waist (Δ -1 ± 1.61 cm), hip (Δ -2.75±1.44 cm) and waist hip ratio circumference (Δ -0.02 ± 0.15 cm). For functional autonomy, TG showed increases post 12 weeks by 30-second chair stand (Δ 3.5±0.4 reps), six minute walk (Δ60.95±7.91 m), back scratch (Δ 3.2 ± 1.36 cm), and time up and go tests (Δ -1,62 ±0,15s). TG also showed increases in muscle strength post 12 weeks in both leg press (Δ 11±1,29 kg) and lat pulldown (Δ11 ±0,75 Kg). For CG, Body composition, functional autonomy and muscle strength did not improved in any moment. Hence, circuit strength training provides significant improvements inmuscle strength, functional performance and anthropometric indicators in sedentary elderly women.

  13. Whole Body Vibration Training - Improving Balance Control and Muscle Endurance

    PubMed Central

    Ritzmann, Ramona; Kramer, Andreas; Bernhardt, Sascha; Gollhofer, Albert

    2014-01-01

    Exercise combined with whole body vibration (WBV) is becoming increasingly popular, although additional effects of WBV in comparison to conventional exercises are still discussed controversially in literature. Heterogeneous findings are attributed to large differences in the training designs between WBV and “control” groups in regard to training volume, load and type. In order to separate the additional effects of WBV from the overall adaptations due to the intervention, in this study, a four-week WBV training setup was compared to a matched intervention program with identical training parameters in both training settings except for the exposure to WBV. In a repeated-measures matched-subject design, 38 participants were assigned to either the WBV group (VIB) or the equivalent training group (CON). Training duration, number of sets, rest periods and task-specific instructions were matched between the groups. Balance, jump height and local static muscle endurance were assessed before and after the training period. The statistical analysis revealed significant interaction effects of group×time for balance and local static muscle endurance (p<0.05). Hence, WBV caused an additional effect on balance control (pre vs. post VIB +13%, p<0.05 and CON +6%, p = 0.33) and local static muscle endurance (pre vs. post VIB +36%, p<0.05 and CON +11%, p = 0.49). The effect on jump height remained insignificant (pre vs. post VIB +3%, p = 0.25 and CON ±0%, p = 0.82). This study provides evidence for the additional effects of WBV above conventional exercise alone. As far as balance and muscle endurance of the lower leg are concerned, a training program that includes WBV can provide supplementary benefits in young and well-trained adults compared to an equivalent program that does not include WBV. PMID:24587114

  14. Effects of feedback-based balance and core resistance training vs. Pilates training on balance and muscle function in older women: a randomized-controlled trial.

    PubMed

    Markovic, Goran; Sarabon, Nejc; Greblo, Zrinka; Krizanic, Valerija

    2015-01-01

    Aging is associated with decline in physical function that could result in the development of physical impairment and disability. Hence, interventions that simultaneously challenge balance ability, trunk (core) and extremity strength of older adults could be particularly effective in preserving and enhancing these physical functions. The purpose of this study was to compare the effects of feedback-based balance and core resistance training utilizing the a special computer-controlled device (Huber®) with the conventional Pilates training on balance ability, neuromuscular function and body composition of healthy older women. Thirty-four older women (age: 70±4 years) were randomly assigned to a Huber group (n=17) or Pilates group (n=17). Both groups trained for 8 weeks, 3 times a week. Maximal isometric strength of the trunk flexors, extensors, and lateral flexors, leg power, upper-body strength, single- and dual-task static balance, and body composition were measured before and after the intervention programs. Significant group×time interactions and main effects of time (p<0.05) were found for body composition, balance ability in standard and dual-task conditions, all trunk muscle strength variables, and leg power in favor of the Huber group. The observed improvements in balance ability under both standard and dual-task conditions in the Huber group were mainly the result of enhanced postural control in medial-lateral direction (p<0.05). Feedback-based balance and core resistance training proved to be more effective in improving single- and dual-task balance ability, trunk muscle strength, leg power, and body composition of healthy older women than the traditional Pilates training. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Comparison of lower limb muscle strength between diabetic neuropathic and healthy subjects using OpenSim.

    PubMed

    Scarton, Alessandra; Jonkers, Ilse; Guiotto, Annamaria; Spolaor, Fabiola; Guarneri, Gabriella; Avogaro, Angelo; Cobelli, Claudio; Sawacha, Zimi

    2017-10-01

    Diabetes neuropathy and vasculopathy are the two major complications of diabetes mellitus, leading to diabetic foot disease, of which the worst consequences are plantar ulcers and amputations. Motor impairments like joint stiffness and loss of balance are distinctive effects of diabetes and they have been extensively explored. However, while altered muscle function has been also assessed through experimentally measured surface electromyography, little is known about muscle forces. The objective of this study was to estimate muscle forces in subjects with diabetes and to use these data to identify differences with respect to a population of healthy subjects matched for age and BMI. This was obtained by generating musculoskeletal models of 10 diabetic and 10 control subjects in OpenSim starting from experimentally recorded data. Dynamic simulations of motion were run and hence muscle forces calculated. Student T test (p<0.05) was used to compare joints kinematics, kinetics and muscle forces between the two populations. Significant changes were observed between lower limb muscle forces and activation of diabetic and healthy subjects, as well as between joints kinematics and kinetics. In particular muscles related to foot movements proved to be stronger in the healthy population. The typical ankle rigidity of the diabetic population was confirmed by a lower range of motion registered at the ankle plantar/flexion angle associated with weaker dorsal-plantar flexor muscles. The information provided by this methodology can help planning specific training programs aiming at augmenting muscle strength and joints mobility, and they can also improve the evaluation of the potential benefits. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Comparison of isokinetic muscle strength and muscle power by types of warm-up.

    PubMed

    Sim, Young-Je; Byun, Yong-Hyun; Yoo, Jaehyun

    2015-05-01

    [Purpose] The purpose of this study was to clarify the influence of static stretching at warm-up on the isokinetic muscle torque (at 60°/sec) and muscle power (at 180°/sec) of the flexor muscle and extensor muscle of the knee joint. [Subjects and Methods] The subjects of this study were 10 healthy students with no medically specific findings. The warm-up group and warm-up with stretching group performed their respective warm-up prior to the isokinetic muscle torque evaluation of the knee joint. One-way ANOVA was performed by randomized block design for each variable. [Results] The results were as follows: First, the flexor peak torque and extensor peak torque of the knee joint tended to decrease at 60°/sec in the warm-up with stretching group compared with the control group and warm-up group, but without statistical significance. Second, extensor power at 180°/sec was also not statistically significant. However, it was found that flexor power increased significantly in the warm-up with stretching group at 180°/sec compared with the control group and warm-up group in which stretching was not performed. [Conclusion] Therefore, it is considered that in healthy adults, warm-up including two sets of stretching for 20 seconds per muscle group does not decrease muscle strength and muscle power.

  17. CCL2 and CCR2 variants are associated with skeletal muscle strength and change in strength with resistance training.

    PubMed

    Harmon, Brennan T; Orkunoglu-Suer, E Funda; Adham, Kasra; Larkin, Justin S; Gordish-Dressman, Heather; Clarkson, Priscilla M; Thompson, Paul D; Angelopoulos, Theodore J; Gordon, Paul M; Moyna, Niall M; Pescatello, Linda S; Visich, Paul S; Zoeller, Robert F; Hubal, Monica J; Tosi, Laura L; Hoffman, Eric P; Devaney, Joseph M

    2010-12-01

    Baseline muscle size and muscle adaptation to exercise are traits with high variability across individuals. Recent research has implicated several chemokines and their receptors in the pathogenesis of many conditions that are influenced by inflammatory processes, including muscle damage and repair. One specific chemokine, chemokine (C-C motif) ligand 2 (CCL2), is expressed by macrophages and muscle satellite cells, increases expression dramatically following muscle damage, and increases expression further with repeated bouts of exercise, suggesting that CCL2 plays a key role in muscle adaptation. The present study hypothesizes that genetic variations in CCL2 and its receptor (CCR2) may help explain muscle trait variability. College-aged subjects [n = 874, Functional Single-Nucleotide Polymorphisms Associated With Muscle Size and Strength (FAMUSS) cohort] underwent a 12-wk supervised strength-training program for the upper arm muscles. Muscle size (via MR imaging) and elbow flexion strength (1 repetition maximum and isometric) measurements were taken before and after training. The study participants were then genotyped for 11 genetic variants in CCL2 and five variants in CCR2. Variants in the CCL2 and CCR2 genes show strong associations with several pretraining muscle strength traits, indicating that inflammatory genes in skeletal muscle contribute to the polygenic system that determines muscle phenotypes. These associations extend across both sexes, and several of these genetic variants have been shown to influence gene regulation.

  18. Respiratory Muscle Strength in Patients With Chronic Obstructive Pulmonary Disease.

    PubMed

    Kim, Nam-Sik; Seo, Jeong-Hwan; Ko, Myoung-Hwan; Park, Sung-Hee; Kang, Seong-Woong; Won, Yu Hui

    2017-08-01

    To compare the respiratory muscle strength between patients with stable and acutely exacerbated (AE) chronic obstructive pulmonary disease (COPD) at various stages. A retrospective medical record review was conducted on patients with COPD from March 2014 to May 2016. Patients were subdivided into COPD stages 1-4 according to the Global Initiative for Chronic Obstructive Lung Disease guidelines: mild, moderate, severe, and very severe. A rehabilitation physician reviewed their medical records and initial assessment, including spirometry, maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), COPD Assessment Test, and modified Medical Research Council scale. We then compared the initial parameters in patients with a stable condition and those at AE status. The AE group (n=94) had significantly lower MIP (AE, 55.93±20.57; stable, 67.88±24.96; p=0.006) and MIP% (AE, 82.82±27.92; stable, 96.64±30.46; p=0.015) than the stable patient group (n=36). MIP, but not MEP, was proportional to disease severity in patients with AE and stable COPD. The strength of the inspiratory muscles may better reflect severity of disease when compared to that of expiratory muscles.

  19. Muscle Strength and Changes in Physical Function in Women With Systemic Lupus Erythematosus.

    PubMed

    Andrews, James S; Trupin, Laura; Schmajuk, Gabriela; Barton, Jennifer; Margaretten, Mary; Yazdany, Jinoos; Yelin, Edward H; Katz, Patricia P

    2015-08-01

    Cross-sectional studies have observed that muscle weakness is associated with worse physical function among women with systemic lupus erythematosus (SLE). The present study examines whether reduced upper and lower extremity muscle strength predict declines in function over time among adult women with SLE. One hundred forty-six women from a longitudinal SLE cohort participated in the study. All measures were collected during in-person research visits approximately 2 years apart. Upper extremity muscle strength was assessed by grip strength. Lower extremity muscle strength was assessed by peak knee torque of extension and flexion. Physical function was assessed using the Short Physical Performance Battery (SPPB). Regression analyses modeled associations of baseline upper and lower extremity muscle strength with followup SPPB scores controlling for baseline SPPB, age, SLE duration, SLE disease activity (Systemic Lupus Activity Questionnaire), physical activity level, prednisone use, body composition, and depression. Secondary analyses tested whether associations of baseline muscle strength with followup in SPPB scores differed between intervals of varying baseline muscle strength. Lower extremity muscle strength strongly predicted changes over 2 years in physical function even when controlling for covariates. The association of reduced lower extremity muscle strength with reduced physical function in the future was greatest among the weakest women. Reduced lower extremity muscle strength predicted clinically significant declines in physical function, especially among the weakest women. Future studies should test whether therapies that promote preservation of lower extremity muscle strength may prevent declines in function among women with SLE. © 2015, American College of Rheumatology.

  20. Muscle strength and fatigue in newly diagnosed patients with myasthenia gravis.

    PubMed

    Vinge, Lotte; Andersen, Henning

    2016-10-01

    Dynamometry is increasingly used as an objective measurement of muscle strength in neurological diseases. No study has applied dynamometry in untreated newly diagnosed patients with myasthenia gravis (MG). Isometric muscle strength at the shoulder, knee, and ankle was determined in 21 MG patients before and after initial anti-myasthenic treatment. Isometric strength was compared with MG evaluation scales. Muscle strength was reduced for knee extensors and shoulder abductors but normal for ankle extensors. Isometric muscle strength did not correlate significantly with manual muscle testing (MG Composite). Dynamometry revealed improved muscle strength of up to 50% (median 17%; range -1.8-49.8) despite no change in the MG Composite score. Dynamometry appears to be a more sensitive method of identifying changes in limb strength than MG evaluation scales. This supports the use of dynamometry in MG patients, especially for evaluation of the effect of anti-myasthenic treatment. Muscle Nerve 54: 709-714, 2016. © 2016 Wiley Periodicals, Inc.

  1. Relationships between HMG-CoA reductase inhibitors (statin) use and strength, balance and falls in older people.

    PubMed

    Haerer, W; Delbaere, K; Bartlett, H; Lord, S R; Rowland, J

    2012-12-01

    To investigate associations between HMG-CoA reductase inhibitor (statin) use and muscle strength, balance, mobility and falls in older people. Five hundred community-dwelling people aged 70-90 years provided information about their medication use and undertook tests of lower limb strength, postural sway, leaning balance (maximal balance range and coordinated stability tests) and functional mobility. Participants were then followed up for 12 months with respect to falls. After adjusting for general health in analyses of covariance procedures, statin users had poorer maximal balance range than non-statin users (P = 0.017). Statin and non-statin users did not differ with respect to strength, postural sway, mobility or falls experienced in the follow-up year. In a sample of healthy older people, statin use was not associated with muscle weakness, postural sway, reduced mobility or falls. Statin users, however, had poorer leaning balance which may potentially increase fall risk in this group. © 2011 The Authors; Internal Medicine Journal © 2011 Royal Australasian College of Physicians.

  2. Spinal mobility and trunk muscle strength in elite hockey players.

    PubMed

    Lindgren, S; Twomey, L

    1988-01-01

    Elite hockey players of both sexes from the Australian Institute of Sport were assessed for lumbar spine mobility, trunk flexion and back extensor muscle strength, hamstring flexibility and postural characteristics over a two year period. All the athletes were more mobile in rotation than the 'normal' West Australian population, and demonstrated flexible hamstrings and powerful back extensor muscles; trunk flexion was less strong initially, but improved after intervention in the form of a specific exercise programme, over the measurement period. A questionnaire disclosed that low back pain is a common complaint of hockey players, but rarely required intensive physical and medical treatment. The term 'hockey player's back' has been coined in recognition of the long flat thoracolumbar spine frequently noted in these subjects. Copyright © 1988 Australian Physiotherapy Association. Published by . All rights reserved.

  3. Cardiorespiratory fitness and muscle strength in pancreatic cancer patients.

    PubMed

    Clauss, Dorothea; Tjaden, Christine; Hackert, Thilo; Schneider, Lutz; Ulrich, Cornelia M; Wiskemann, Joachim; Steindorf, Karen

    2017-09-01

    Cancer patients frequently experience reduced physical fitness due to the disease itself as well as treatment-related side effects. However, studies on physical fitness in pancreatic cancer patients are missing. Therefore, we assessed cardiorespiratory fitness and muscle strength of pancreatic cancer patients. We included 65 pancreatic cancer patients, mostly after surgical resection. Cardiorespiratory fitness was assessed using cardiopulmonary exercise testing (CPET) and 6-min walk test (6MWT). Hand-held dynamometry was used to evaluate isometric muscle strength. Physical fitness values were compared to reference values of a healthy population. Associations between sociodemographic and clinical variables with patients' physical fitness were analyzed using multiple regression models. Cardiorespiratory fitness (VO 2 peak, 20.5 ± 6.9 ml/min/kg) was significantly lower (-24%) compared to healthy reference values. In the 6MWT pancreatic cancer patients nearly reached predicted values (555 vs. 562 m). Maximal voluntary isometric contraction (MVIC) of the upper (-4.3%) and lower extremities (-13.8%) were significantly lower compared to reference values. Overall differences were larger in men than those in women. Participating in regular exercise in the year before diagnosis was associated with greater VO 2 peak (p < .05) and MVIC of the knee extensors (p < .05). Pancreatic cancer patients had significantly impaired physical fitness with regard to both cardiorespiratory function and isometric muscle strength, already in the early treatment phase (median 95 days after surgical resection). Our findings underline the need to investigate exercise training in pancreatic cancer patients to counteract the loss of physical fitness.

  4. Experimental knee joint pain during strength training and muscle strength gain in healthy subjects: a randomized controlled trial.

    PubMed

    Sørensen, T J; Langberg, H; Hodges, P W; Bliddal, H; Henriksen, M

    2012-01-01

    Knee joint pain and reduced quadriceps strength are cardinal symptoms in many knee pathologies. In people with painful knee pathologies, quadriceps exercise reduces pain, improves physical function, and increases muscle strength. A general assumption is that pain compromises muscle function and thus may prevent effective rehabilitation. This study evaluated the effects of experimental knee joint pain during quadriceps strength training on muscle strength gain in healthy individuals. Twenty-seven healthy untrained volunteers participated in a randomized controlled trial of quadriceps strengthening (3 times per week for 8 weeks). Participants were randomized to perform resistance training either during pain induced by injections of painful hypertonic saline (pain group, n = 13) or during a nonpainful control condition with injection of isotonic saline (control group, n = 14) into the infrapatellar fat pad. The primary outcome measure was change in maximal isokinetic muscle strength in knee extension/flexion (60, 120, and 180 degrees/second). The group who exercised with pain had a significantly larger improvement in isokinetic muscle strength at all angular velocities of knee extension compared to the control group. In knee flexion there were improvements in isokinetic muscle strength in both groups with no between-group differences. Experimental knee joint pain improved the training-induced gain in muscle strength following 8 weeks of quadriceps training. It remains to be studied whether knee joint pain has a positive effect on strength gain in patients with knee pathology. Copyright © 2012 by the American College of Rheumatology.

  5. Muscle hypertrophy, strength development, and serum hormones during strength training in elderly women with fibromyalgia.

    PubMed

    Valkeinen, H; Häkkinen, K; Pakarinen, A; Hannonen, P; Häkkinen, A; Airaksinen, O; Niemitukia, L; Kraemer, W J; Alén, M

    2005-01-01

    To examine the effects of strength training on maximal force, cross-sectional area (CSA), and electromyographic (EMG) activity of muscles and serum hormone concentrations in elderly females with fibromyalgia (FM). Twenty-six patients with FM were randomly assigned to a training (FMT; n = 13; mean age 60 years) or a control (FMC; n = 13; 59 years) group. FMT performed progressive strength training twice a week for 21 weeks. The measurements included maximal isometric and concentric leg extension forces, EMG activity of the vastus lateralis and medialis, CSA of the quadriceps femoris, and serum concentrations of testosterone (T), free testosterone (FT), growth hormone (GH), insulin-like growth factor-1 (IGF-1), dehydroepiandrosterone sulfate (DHEAS), and cortisol. Subjectively perceived symptoms of FM were also assessed. All patients were able to complete the training. In FMT strength training led to increases of 36% (p<0.001) and 33% (p<0.001) in maximal isometric and concentric forces, respectively. The CSA increased by 5% (p<0.001) and the EMG activity in isometric action by 47% (p<0.001) and in concentric action by 57% (p<0.001). Basal serum hormone concentrations remained unaltered during strength training. The subjective perceived symptoms showed a minor decreasing tendency (ns). No statistically significant changes occurred in any of these parameters in FMC. Progressive strength training increases strength, CSA, and voluntary activation of the trained muscles in elderly women with FM, while the measured basal serum hormone concentrations remain unaltered. Strength training benefits the overall physical fitness of the patients without adverse effects or any exacerbation of symptoms and should be included in the rehabilitation programmes of elderly patients with FM.

  6. Profile of isokinetic eccentric-to-concentric strength ratios of shoulder rotator muscles in elite female team handball players.

    PubMed

    Andrade, Marilia Dos Santos; Fleury, Anna Maria; de Lira, Claudio Andre Barbosia; Dubas, Joao Paulo; da Silva, Antonio Carlos

    2010-05-01

    The purpose of this study was to establish the isokinetic profile of shoulder rotator muscles strength in female handball players. Twenty-seven handball players performed concentric and eccentric strength tests of both dominant and non-dominant upper limbs on an isokinetic dynamometer. Internal and external rotator muscles peak torque was assessed at 1.05, 3.14, and 5.23 rad . s(-1) in concentric mode and at 3.14 and 5.23 rad . s(-1) in eccentric mode. Concentric balance ratio and functional ratio were obtained. Bi-lateral deficiency was compared. Concentric strength for internal and external rotation was significantly greater for the dominant than for the non-dominant limb for all speeds (P < or = 0.0001). For eccentric actions, internal rotator muscles were stronger in the dominant than the non-dominant limb (P < or = 0.0001) at both speeds. Concentric balance and functional balance ratios did not differ between sides at 3.14 rad . s(-1) (P = 0.1631), but at 5.23 rad . s(-1) the functional balance ratio in the dominant limb was lower than for the non-dominant limb (P = 0.0500). Although the dominant side was stronger than the non-dominant side, balance concentric ratios remained the same, with only the functional strength ratio different at 5.23 rad . s(-1). Our results suggest that concentric strength exercises be used for internal and external rotators on the non-dominant side, and functional exercise that improves eccentric rotation strength for prevention programmes.

  7. Effects of 8 Weeks’ Specific Physical Training on the Rotator Cuff Muscle Strength and Technique of Javelin Throwers

    PubMed Central

    Kim, Hyeyoung; Lee, Youngsun; Shin, Insik; Kim, Kitae; Moon, Jeheon

    2014-01-01

    [Purpose] For maximum efficiency and to prevent injury during javelin throwing, it is critical to maintain muscle balance and coordination of the rotator cuff and the glenohumeral joint. In this study, we investigated the change in the rotator cuff muscle strength, throw distance and technique of javelin throwers after they had performed a specific physical training that combined elements of weight training, function movement screen training, and core training. [Subjects] Ten javelin throwers participated in this study: six university athletes in the experimental group and four national-level athletes in the control group. [Methods] The experimental group performed 8 weeks of the specific physical training. To evaluate the effects of the training, measurements were performed before and after the training for the experimental group. Measurements comprised anthropometry, isokinetic muscle strength measurements, the function movement screen test, and movement analysis. [Results] After the specific physical training, the function movement screen score and external and internal rotator muscle strength showed statistically significant increases. Among kinematic factors, only pull distance showed improvement after training. [Conclusion] Eight weeks of specific physical training for dynamic stabilizer muscles enhanced the rotator cuff muscle strength, core stability, throw distance, and flexibility of javelin throwers. These results suggest that specific physical training can be useful for preventing shoulder injuries and improving the performance for javelin throwers. PMID:25364111

  8. Effects of 8 weeks' specific physical training on the rotator cuff muscle strength and technique of javelin throwers.

    PubMed

    Kim, Hyeyoung; Lee, Youngsun; Shin, Insik; Kim, Kitae; Moon, Jeheon

    2014-10-01

    [Purpose] For maximum efficiency and to prevent injury during javelin throwing, it is critical to maintain muscle balance and coordination of the rotator cuff and the glenohumeral joint. In this study, we investigated the change in the rotator cuff muscle strength, throw distance and technique of javelin throwers after they had performed a specific physical training that combined elements of weight training, function movement screen training, and core training. [Subjects] Ten javelin throwers participated in this study: six university athletes in the experimental group and four national-level athletes in the control group. [Methods] The experimental group performed 8 weeks of the specific physical training. To evaluate the effects of the training, measurements were performed before and after the training for the experimental group. Measurements comprised anthropometry, isokinetic muscle strength measurements, the function movement screen test, and movement analysis. [Results] After the specific physical training, the function movement screen score and external and internal rotator muscle strength showed statistically significant increases. Among kinematic factors, only pull distance showed improvement after training. [Conclusion] Eight weeks of specific physical training for dynamic stabilizer muscles enhanced the rotator cuff muscle strength, core stability, throw distance, and flexibility of javelin throwers. These results suggest that specific physical training can be useful for preventing shoulder injuries and improving the performance for javelin throwers.

  9. How protein materials balance strength, robustness, and adaptability

    PubMed Central

    Buehler, Markus J.; Yung, Yu Ching

    2010-01-01

    Proteins form the basis of a wide range of biological materials such as hair, skin, bone, spider silk, or cells, which play an important role in providing key functions to biological systems. The focus of this article is to discuss how protein materials are capable of balancing multiple, seemingly incompatible properties such as strength, robustness, and adaptability. To illustrate this, we review bottom-up materiomics studies focused on the mechanical behavior of protein materials at multiple scales, from nano to macro. We focus on alpha-helix based intermediate filament proteins as a model system to explain why the utilization of hierarchical structural features is vital to their ability to combine strength, robustness, and adaptability. Experimental studies demonstrating the activation of angiogenesis, the growth of new blood vessels, are presented as an example of how adaptability of structure in biological tissue is achieved through changes in gene expression that result in an altered material structure. We analyze the concepts in light of the universality and diversity of the structural makeup of protein materials and discuss the findings in the context of potential fundamental evolutionary principles that control their nanoscale structure. We conclude with a discussion of multiscale science in biology and de novo materials design. PMID:20676305

  10. Core stability training on lower limb balance strength.

    PubMed

    Dello Iacono, Antonio; Padulo, Johnny; Ayalon, Moshe

    2016-01-01

    This study aimed to assess the effects of core stability training on lower limbs' muscular asymmetries and imbalances in team sport. Twenty footballers were divided into two groups, either core stability or control group. Before each daily practice, core stability group (n = 10) performed a core stability training programme, while control group (n = 10) did a standard warm-up. The effects of the core stability training programme were assessed by performing isokinetic tests and single-leg countermovement jumps. Significant improvement was found for knee extensors peak torque at 3.14 rad · s(-1) (14%; P < 0.05), knee flexors peak torque at 1.05 and 3.14 rad · s(-1) (19% and 22% with P < 0.01 and P < 0.01, respectively) and peak torque flexors/extensors ratios at 1.05 and 3.14 rad · s(-1) (7.7% and 8.5% with P < 0.05 and P < 0.05, respectively) only in the core stability group. The jump tests showed a significant reduction in the strength asymmetries in core stability group (-71.4%; P = 0.02) while a concurrent increase was seen in the control group (33.3%; P < 0.05). This study provides practical evidence in combining core exercises for optimal lower limbs strength balance development in young soccer players.

  11. Improving Strength-Ductility Balance of High Strength Dual-Phase Steels by Addition of Vanadium

    NASA Astrophysics Data System (ADS)

    Gong, Yu; Hua, M.; Uusitalo, J.; DeArdo, A. J.

    For galvanized or galvannealed steels to be commercially successful, they must exhibit several attributes: (i) easy and inexpensive processing in the hot mill, cold mill and on the coating line, (ii) high strength with good formability and spot weldability, and (iii) good corrosion resistance, especially after cold forming. For good corrosion resistance, the coating must have sufficient coverage, be of uniform thickness, and most importantly, the coating must survive the cold stamping or forming operation. The purpose of this paper is to present research aiming at improving the steel substrate, such that high strength can be obtained while maintaining good global formability (tensile ductility), local formability (sheared-edge ductility), and good spot weldability. It is well-known that the strength of DP steels is controlled by several factors, including the amount of martensite found in the final microstructure. Recent research has revealed that the amount of austenite formed during intercritical annealing can be strongly influenced by the annealing temperature and the pre-annealing conditions of the hot band (coiling temperature) and cold band (% cold reduction). Current experiments have explored the combination of pre-annealing conditions and four annealing practices to help define the best practice to optimize the strength-formability balance in these higher strength DP steels. The steels used in these experiments contained (i) low carbon content for good spot weldability, (ii) the hardenability additions Mo and Cr for strength, and (iii) V for grain refinement, precipitation hardening and temper resistance. When processed correctly, these steels exhibited UTS levels up to 1000MPa, total elongation to 25%, reduction in area to 45%, and Hole Expansion Ratios to 50%. The results of this program will be presented and discussed.

  12. Skeletal muscle strength and endurance are maintained during moderate dehydration.

    PubMed

    Périard, J D; Tammam, A H; Thompson, M W

    2012-08-01

    This study investigated the effects of moderate dehydration (~2.5% body weight) on muscle strength and endurance using percutaneous electrical stimulation to quantify central and peripheral fatigue, and isolate the combined effects of exercise-heat stress and dehydration, vs. the effect of dehydration alone. Force production and voluntary activation were calculated in 10 males during 1 brief and 15 repeated maximal voluntary isometric contractions performed prior to (control) walking in the heat (35°C), immediately following exercise, and the next morning (dehydration). The protocol was also performed in a euhydrated state. During the brief contractions, force production and voluntary activation were maintained in all trials. In contrast, force production decreased throughout the repeated contractions, regardless of hydration status (P<0.001). The decline in force was greater immediately following exercise-heat stress dehydration compared with control and euhydration (P<0.001). When dehydration was isolated from acute post-exercise dehydration, force production was maintained similarly to control and euhydration. Despite the progressive decline in force production and the increased fatigability observed during the repeated contractions, voluntary activation remained elevated throughout each muscle function test. Therefore, moderate dehydration, isolated from acute exercise-heat stress, does not appear to influence strength during a single contraction or enhance fatigability. © Georg Thieme Verlag KG Stuttgart · New York.

  13. The relation between knee muscle strength and performance tests in orienteering athletes.

    PubMed

    Çinar-Medeni, Özge; Colakoglu, Fatma F; Yüce, Koray; Ipekoğlu, Gökhan; Baltaci, Gul

    2016-11-01

    The aim of this study was to analyze the effect of knee muscle strength on performance tests in orienteers. Thirty-seven orienteers were voluntarily included in this study. Isokinetic knee flexor and extensor muscles' strength was assessed at 120°/s velocity for both "dominant leg" (DL) and "non-dominant leg" (NDL). "Single-legged hop test" (SLHT), "flamingo balance test" (FBT), "star excursion balance test" (SEBT), vertical jump-and-reach test (for anaerobic power), T-drill test and 20-meter shuttle run test (for aerobic power) were carried out. Correlation and regression analyses were performed on the data. VO2max levels showed moderate correlations with DL's "flexor peak torque" (FPT) and NDL's "extensor peak torque" (EPT) and FPT values respectively (r=0.49, r=0.38, r=0.58). FPT of NDL was a predictor of VO2max level (R2=0.33). Anaerobic power has a relationship with EPT of NDL (r=0.43) and T-drill test with EPT and FPT values of both DL and NDL respectively (r=-0.35, r=-0.63, r=-0.53, r=-0.58). EPT of NDL was a predictor for anaerobic power (R2=0.19) and FPT of DL for agility (R2=0.40). Nonparametric linear regression results showed that EPT is a predictor in DL (median slope=-0.71, P=0.01), and FPT in NDL (median slope=-0.90, P=0.006) for FBT. FPT was a predictor of SEBT scores for both legs (0.13muscle strength are of importance to improve orienteering performance.

  14. The Association of Flexibility, Balance, and Lumbar Strength with Balance Ability: Risk of Falls in Older Adults

    PubMed Central

    Emilio, Emilio J. Martínez-López; Hita-Contreras, Fidel; Jiménez-Lara, Pilar M.; Latorre-Román, Pedro; Martínez-Amat, Antonio

    2014-01-01

    The purpose of the present study was to determine the effects of a proprioceptive training program on older adults, as well as to analyze the association between flexibility, balance and lumbar strength (physical fitness test) with balance ability and fall risk (functional balance tests). This study was a controlled, longitudinal trial with a 12-week follow-up period. Subjects from a population of older adults were allocated to the intervention group (n = 28) or to the usual care (control) group (n = 26). Subjects performed proprioceptive training twice weekly (6 specific exercises with Swiss ball and BOSU). Each session included 50 minutes (10 minutes of warm-up with slow walk, 10 minutes of mobility and stretching exercises, 30 minutes of proprioceptive exercises). The outcome variables were physical fitness (lower-body flexibility, hip-joint mobility, dynamic balance, static balance, and lumbar strength) and functional balance (Berg scale and Tinetti test). The experimental group obtained significantly higher values than the control group in lower-body flexibility, dynamic balance, and lumbar strength (p = 0.019, p < 0.001, and p = 0.034 respectively). Hip-joint mobility, dynamic balance, and lumbar strength were positively associated with balance ability (p < 0.001, p < 0.001, and p = 0.014, respectively) and the prevention of falls (p = 0.001, p < 0.001, and p = 0.017 respectively). These findings suggest that a 12-week proprioception program intervention (twice a week) significantly improves flexibility, balance, and lumbar strength in older adults. Hip-joint mobility, dynamic balance and lumbar strength are positively associated to balance ability and the risk of falls in older adults. This proprioceptive training does not show a significant improvement in hip-joint mobility or static balance. Key points A 12-week proprioceptive intervention program (two times per week) significantly improves flexibility, balance, and lumbar strength in older adults. The

  15. Effect of the Power Balance® band on static balance, hamstring flexibility, and arm strength in adults.

    PubMed

    Verdan, Princess J R; Marzilli, Thomas S; Barna, Geanina I; Roquemore, Anntionette N; Fenter, Brad A; Blujus, Brittany; Gosselin, Kevin P

    2012-08-01

    The purpose of this study was to determine the effect of Power Balance® bands on strength, flexibility, and balance. Strength and flexibility were measured using the MicroFit system. Strength was measured via a bicep curl and flexibility via the sit-and-reach method. Balance was measured by the BIODEX System SD. There were 4 different conditions for the balance test: eyes open on a firm surface (EOFS), eyes closed on a firm surface (ECFS), eyes open on a foam surface (EOFoS), and eyes closed on a foam surface (ECFoS). There were 24 subjects in the study (10 men and 14 women). A counterbalance, double-blind, placebo, controlled within-subject design was used. Each of the subjects participated in 3 treatment sessions, consisting of Power Balance®, placebo band, and no band. An alpha level of p ≤ 0.05 was set a priori. There were no significant differences in strength, flexibility, or balance with regard to the treatments used. There was a significant difference between the conditions in the balance test (p = 0.000): EOFS (0.51), ECFS (0.68), EOFoS (0.99), and ECFoS (2.18); however, these were independent of the treatment conditions. The results indicate that the Power Balance® bands did not have an effect on strength, flexibility, or balance.

  16. Protein requirements and muscle mass/strength changes during intensive training in novice bodybuilders.

    PubMed

    Lemon, P W; Tarnopolsky, M A; MacDougall, J D; Atkinson, S A

    1992-08-01

    This randomized double-blind cross-over study assessed protein (PRO) requirements during the early stages of intensive bodybuilding training and determined whether supplemental PRO intake (PROIN) enhanced muscle mass/strength gains. Twelve men [22.4 +/- 2.4 (SD) yr] received an isoenergetic PRO (total PROIN 2.62 g.kg-1.day-1) or carbohydrate (CHO; total PROIN 1.35 g.kg-1.day-1) supplement for 1 mo each during intensive (1.5 h/day, 6 days/wk) weight training. On the basis of 3-day nitrogen balance (NBAL) measurements after 3.5 wk on each treatment (8.9 +/- 4.2 and -3.4 +/- 1.9 g N/day, respectively), the PROIN necessary for zero NBAL (requirement) was 1.4-1.5 g.kg-1.day-1. The recommended intake (requirement + 2 SD) was 1.6-1.7 g.kg-1.day-1. However, strength (voluntary and electrically evoked) and muscle mass [density, creatinine excretion, muscle area (computer axial tomography scan), and biceps N content] gains were not different between diet treatments. These data indicate that, during the early stages of intensive bodybuilding training, PRO needs are approximately 100% greater than current recommendations but that PROIN increases from 1.35 to 2.62 g.kg-1.day-1 do not enhance muscle mass/strength gains, at least during the 1st mo of training. Whether differential gains would occur with longer training remains to be determined.

  17. The eccentric, concentric strength relationship of the hamstring muscles in chronic low back pain.

    PubMed

    Marshall, Paul W M; Mannion, Jamie; Murphy, Bernadette A

    2010-02-01

    The objective of this study was to measure hamstring muscle eccentric and concentric strength in individuals with and without low back pain (LBP). Two composite scores for the relative balance of eccentric to concentric strength at the different movement velocities were calculated (the DEC and SEC), to determine whether or not self perceived pain, disability, or fear avoidance measures were associated with hamstring strength characteristics. Cross-sectional repeated measures design. University laboratory. Fifteen individuals with chronic LBP and 15 matched controls. Isokinetic eccentric and concentric strength at 30 degrees s(-1) and 120 degrees s(-1)(.) Composite scores (DEC and SEC) based on peak torque were calculated to evaluate the relationship between the different muscle actions across the test velocities. Self report measures included the Oswestry disability index, general health and well being, fear avoidance, and pain. Eccentric/concentric strength ratio at 30 degrees s(-1) was higher for the LBP group (F(1,58)=4.81, p=0.032). The SEC was also higher for the LBP (F(1,58)=5.97, p=0.018). Fear avoidance beliefs and mental well-being were significantly associated with the SEC only in the LBP group (adjusted r(2)=0.26, (F(2,27)=5.8, p=.008). For the control group both the DEC and SEC were associated with self report measures. Matched differences between groups' for the SEC were best explained by fear avoidance beliefs about work (adjusted r(2)=0.12, F(1,28)=5.1, p=0.03). Reduced concentric relative to eccentric strength is best identified by the SEC. The SEC was significantly associated with impaired self report measures of fear avoidance and mental well being in individuals with LBP. Differences between groups for the SEC were best explained by fear avoidance beliefs about work.

  18. Association Between Muscle Wasting and Muscle Strength in Patients WHO Developed Severe Sepsis and Septic Shock.

    PubMed

    Borges, Rodrigo Cerqueira; Soriano, Francisco Garcia

    2018-05-11

    To evaluate the association between the rectus femoris cross-sectional area (RFCSA) and the muscular strength obtained at the bedside in patients forwarded to the intensive care unit (ICU) for severe sepsis and septic shock. A prospective cohort study. RFCSA was assessed by ultrasound on the following day of the ICU admission and monitored during hospitalization. The patients performed clinical tests of muscle strength (Medical Research Council (MRC) scale and handgrip dynamometry), when they could understand the verbal commands of the examiners. In 37 patients hospitalized for sepsis there was a significant decline in RFCSA of 5.18 (4.49-5.96)cm on the 2nd day of ICU for 4.37 (3.71-5.02)cm at hospital discharge. Differently, the handgrip strength showed an increase from the awakening of 12.00 (7.00-20.00)Kgf to 19.00 (14.00-26.00)Kgf until hospital discharge. Patients in mechanical ventilation had a greater tendency to decline in the RFCSA compared to patients who did not receive mechanical ventilation, however without being significant (p = 0.08). There was a negative association between RFCSA delta (2nd day of ICU - ICU discharge) and handgrip strength (r = 0.51, p < 0.05), and a male and SOFA score positive association with the RFCSA delta. There was an association of RFCSA with clinical muscle strength tests. In addition, it has been shown that sepsis can lead to short-term muscle degradation, regardless of whether they are submitted to mechanical ventilation or not.

  19. Influence of muscle strength on early mobility in critically ill adult patients: Systematic literature review.

    PubMed

    Roberson, Audrey R; Starkweather, Angela; Grossman, Catherine; Acevedo, Edmund; Salyer, Jeanne

    Muscle strength may be one indicator of readiness to mobilize that can be used to guide decisions regarding early mobility efforts and to progressively advance mobilization. To provide a synthesis of current measures of muscle strength in the assessment of early mobilization in critically ill adult patients who are receiving MV therapy. Research studies conducted between 2000-2015 were identified using PubMed, CINHAL, MEDLINE, and the Cochrane Database of Systematic Reviews databases using the search terms "muscle strength", "intensive care", "mechanical ventilation" and "muscle weakness". Nine articles used manual muscle testing, the Medical Research Council scale and/or hand-held dynamometer to provide objective measures for assessing muscle strength in the critically ill adult patient population. Further research is needed to examine the application of standardized measures of muscle strength for guiding decisions regarding early and progressive advancement of mobility goals in adult ICU patients on MV. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Relationships between muscular strength and the level of energy sources in the muscle.

    PubMed

    Wit, A; Juskiak, R; Wit, B; Zieliński, J R

    1978-01-01

    Relationships between muscular strength and the level of energy sources in the muscle. Acta Physiol. Pol., 1978, 29 (2): 139--151. An attempt was made to establish a relationship between the post-excercise changes in the level of anaerobic energy sources and changes in the muscular strength. The gastrocnemius muscle of Wistar rats was examined. The muscle strength was measured by the resistance tensometry. In muscle specimens ATP, CP and glycogen contents were determined. It was demonstrated that changes in the post-excersise muscle response to electric stimulus have a phasic character resembling the overcompensation curve. The percent changes in the content of anaerobic energy sources in the muscle after contractions varying in duration suggests also overcompensation the muscle content of these substances. The parallelity between the time of appearance of peak overcompensation phase in the muscle strength and in the post-exercise level of musclar ATP, CP and glycogen contents suggest a casual relationship between these changes.

  1. Effects of strength training, detraining and retraining in muscle strength, hypertrophy and functional tasks in older female adults.

    PubMed

    Correa, Cleiton S; Cunha, Giovani; Marques, Nise; Oliveira-Reischak, Ãlvaro; Pinto, Ronei

    2016-07-01

    Previous studies presented different results regarding the maintenance time of muscular adaptations after strength training and the ability to resume the gains on muscular performance after resumption of the training programme. This study aimed to verify the effect of strength training on knee extensors and elbow flexor muscle strength, rectus femoris muscle volume and functional performance in older female adults after 12 weeks of strength training, 1 year of detraining and followed by 12 weeks of retraining. Twelve sedentary older women performed 12 weeks of strength training, 1 year of detraining and 12 weeks of retraining. The strength training was performed twice a week, and the assessment was made four times: at the baseline, after the strength training, after the detraining and after the retraining. The knee extensor and elbow flexor strength, rectus femoris muscle volume and functional task were assessed. Strength of knee extensor and elbow flexor muscles, rectus femoris muscle volume and 30-s sit-to-stand increased from baseline to post-training (respectively, 40%, 70%, 38% and 46%), decreased after detraining (respectively, -36%, -64%, -35% and -43%) and increased again these parameters after retraining (35%, 68%, 36% and 42%). Strength training induces gains on strength and hypertrophy, also increased the performance on functional tasks after the strength training. The stoppage of the strength caused strength loss and reduction of functional performance. The resumption of the strength training promoted the same gains of muscular performance in older female adults. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  2. Diurnal and day-to-day variation of isometric muscle strength in myasthenia gravis.

    PubMed

    Vinge, Lotte; Jakobsen, Johannes; Pedersen, Asger Roer; Andersen, Henning

    2016-01-01

    In patients with myasthenia gravis (MG), muscle strength is expected to decrease gradually during the day due to physical activities. Isometric muscle strength at the shoulder, knee, and ankle was determined in 10 MG patients (MGFA class II-IV) who were receiving usual medical treatment and in 10 control subjects. To determine diurnal and day-to-day variation, muscle strength was measured 4 times during day 1 and once at day 2. Knee extension strength decreased during the day in both patients and controls. Neither diurnal nor day-to-day variation of muscle strength was higher in patients compared with controls. Patients with mild to moderate MG did not have increased variation of isometric muscle strength during the day or from day-to-day compared with controls. This suggests that isometric muscle performance can be determined with high reproducibility in similar groups of MG patients without regard to time of day. © 2015 Wiley Periodicals, Inc.

  3. Manual muscle testing: a method of measuring extremity muscle strength applied to critically ill patients.

    PubMed

    Ciesla, Nancy; Dinglas, Victor; Fan, Eddy; Kho, Michelle; Kuramoto, Jill; Needham, Dale

    2011-04-12

    Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, and persistent nerve and muscle impairments after hospital discharge. Using an explicit protocol with a structured approach to training and quality assurance of research staff, manual muscle testing (MMT) is a highly reliable method for assessing strength, using a standardized clinical examination, for patients following ARDS, and can be completed with mechanically ventilated patients who can tolerate sitting upright in bed and are able to follow two-step commands. (7, 8) This video demonstrates a protocol for MMT, which has been taught to ≥ 43 research staff who have performed >800 assessments on >280 ARDS survivors. Modifications for the bedridden patient are included. Each muscle is tested with specific techniques for positioning, stabilization, resistance, and palpation for each score of the 6-point ordinal Medical Research Council scale. Three upper and three lower extremity muscles are graded in this protocol: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, and ankle dorsiflexion. These muscles were chosen based on the standard approach for evaluating patients for ICU-acquired weakness used in prior publications. (1,2).

  4. Unilateral lower limb strength assessed using the Nintendo Wii Balance Board: a simple and reliable method.

    PubMed

    Blomkvist, A W; Andersen, S; de Bruin, E; Jorgensen, M G

    2017-10-01

    Lower limb weakness is an important risk factor for fall accidents and a predictor for all-cause mortality among older adults. Unilateral whole-lower limb strength may be a better measure of fall risk than the bilateral measure. In addition, a number of clinical conditions affect only one leg, and thus this type of assessment is relevant in clinical settings. To explore the intra-rater reproducibility of the Nintendo Wii Balance Board (WBB) to measure unilateral whole-lower limb strength and to compare the method with stationary isometric muscle apparatus (SID). Intra-rater test-retest design with 1 week between sessions. Thirty community-dwelling older adults (69 ± 4.2 years) were enrolled and examined for maximum lower limb strength in their dominant and non-dominant leg. Intraclass correlation coefficient (ICC) was calculated to describe relative reproducibility, while standard error of measurement (SEM), limits of agreement (LOA) and smallest real difference (SRD) were calculated to describe absolute reproducibility between test sessions. Concurrent validity with the SID was explored using the Pearson product-moment correlation coefficient (PCC). No systematic difference was observed between test sessions. ICC was 0.919-0.950 and SEM, LOA and SRD was 2.9-4.1 kg, 24.1-28.3 kg and 7.6-11.3 kg, respectively. Further, the PCC was 0.755 and 0.730 for the dominant limb and the non-dominant limb, respectively. A high relative and an acceptable absolute reproducibility was seen when using the Nintendo Wii Balance Board for testing unilateral lower limb strength in community-dwelling older adults. The WBB correlated strongly with the SID.

  5. Characteristics of locomotion, muscle strength, and muscle tissue in regenerating rat skeletal muscles.

    PubMed

    Iwata, Akira; Fuchioka, Satoshi; Hiraoka, Koichi; Masuhara, Mitsuhiko; Kami, Katsuya

    2010-05-01

    Although numerous studies have aimed to elucidate the mechanisms used to repair the structure and function of injured skeletal muscles, it remains unclear how and when movement recovers following damage. We performed a temporal analysis to characterize the changes in movement, muscle function, and muscle structure after muscle injury induced by the drop-mass technique. At each time-point, movement recovery was determined by ankle kinematic analysis of locomotion, and functional recovery was represented by isometric force. As a histological analysis, the cross-sectional area of myotubes was measured to examine structural regeneration. The dorsiflexion angle of the ankle, as assessed by kinematic analysis of locomotion, increased after injury and then returned to control levels by day 14 post-injury. The isometric force returned to normal levels by day 21 post-injury. However, the size of the myotubes did not reach normal levels, even at day 21 post-injury. These results indicate that recovery of locomotion occurs prior to recovery of isometric force and that functional recovery occurs earlier than structural regeneration. Thus, it is suggested that recovery of the movement and function of injured skeletal muscles might be insufficient as markers for estimating the degree of neuromuscular system reconstitution.

  6. Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis

    PubMed Central

    Behm, David G.; Young, James D.; Whitten, Joseph H. D.; Reid, Jonathan C.; Quigley, Patrick J.; Low, Jonathan; Li, Yimeng; Lima, Camila D.; Hodgson, Daniel D.; Chaouachi, Anis; Prieske, Olaf; Granacher, Urs

    2017-01-01

    Numerous national associations and multiple reviews have documented the safety and efficacy of strength training for children and adolescents. The literature highlights the significant training-induced increases in strength associated with youth strength training. However, the effectiveness of youth strength training programs to improve power measures is not as clear. This discrepancy may be related to training and testing specificity. Most prior youth strength training programs emphasized lower intensity resistance with relatively slow movements. Since power activities typically involve higher intensity, explosive-like contractions with higher angular velocities (e.g., plyometrics), there is a conflict between the training medium and testing measures. This meta-analysis compared strength (e.g., training with resistance or body mass) and power training programs (e.g., plyometric training) on proxies of muscle strength, power, and speed. A systematic literature search using a Boolean Search Strategy was conducted in the electronic databases PubMed, SPORT Discus, Web of Science, and Google Scholar and revealed 652 hits. After perusal of title, abstract, and full text, 107 studies were eligible for inclusion in this systematic review and meta-analysis. The meta-analysis showed small to moderate magnitude changes for training specificity with jump measures. In other words, power training was more effective than strength training for improving youth jump height. For sprint measures, strength training was more effective than power training with youth. Furthermore, strength training exhibited consistently large magnitude changes to lower body strength measures, which contrasted with the generally trivial, small and moderate magnitude training improvements of power training upon lower body strength, sprint and jump measures, respectively. Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with the unilateral

  7. Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis.

    PubMed

    Behm, David G; Young, James D; Whitten, Joseph H D; Reid, Jonathan C; Quigley, Patrick J; Low, Jonathan; Li, Yimeng; Lima, Camila D; Hodgson, Daniel D; Chaouachi, Anis; Prieske, Olaf; Granacher, Urs

    2017-01-01

    Numerous national associations and multiple reviews have documented the safety and efficacy of strength training for children and adolescents. The literature highlights the significant training-induced increases in strength associated with youth strength training. However, the effectiveness of youth strength training programs to improve power measures is not as clear. This discrepancy may be related to training and testing specificity. Most prior youth strength training programs emphasized lower intensity resistance with relatively slow movements. Since power activities typically involve higher intensity, explosive-like contractions with higher angular velocities (e.g., plyometrics), there is a conflict between the training medium and testing measures. This meta-analysis compared strength (e.g., training with resistance or body mass) and power training programs (e.g., plyometric training) on proxies of muscle strength, power, and speed. A systematic literature search using a Boolean Search Strategy was conducted in the electronic databases PubMed, SPORT Discus, Web of Science, and Google Scholar and revealed 652 hits. After perusal of title, abstract, and full text, 107 studies were eligible for inclusion in this systematic review and meta-analysis. The meta-analysis showed small to moderate magnitude changes for training specificity with jump measures. In other words, power training was more effective than strength training for improving youth jump height. For sprint measures, strength training was more effective than power training with youth. Furthermore, strength training exhibited consistently large magnitude changes to lower body strength measures, which contrasted with the generally trivial, small and moderate magnitude training improvements of power training upon lower body strength, sprint and jump measures, respectively. Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with the unilateral

  8. Cut points of muscle strength associated with metabolic syndrome in men.

    PubMed

    Sénéchal, Martin; McGavock, Jonathan M; Church, Timothy S; Lee, Duck-Chul; Earnest, Conrad P; Sui, Xuemei; Blair, Steven N

    2014-08-01

    The loss of muscle strength with age increases the likelihood of chronic conditions, including metabolic syndrome (MetS). However, the minimal threshold of muscle strength at which the risk for MetS increases has never been established. This study aimed to identify a threshold of muscle strength associated with MetS in men. We created receiver operating curves for muscle strength and the risk of MetS from a cross-sectional sample of 5685 men age <50 yr and 1541 men age ≥50 yr enrolled in the Aerobics Center Longitudinal Study. The primary outcome measure, the MetS, was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Upper and lower body muscle strength was treated as a composite measure of one-repetition maximum tests on bench and leg press and scaled to body weight. Low muscle strength was defined as the lowest age-specific 20th percentile, whereas high muscle strength was defined as composite muscle strength above the 20th percentile. In men aged <50 yr, the odds of MetS were 2.20-fold (95% confidence interval = 1.89-2.54) higher in those with low muscle strength, independent of age, smoking, and alcohol intake. The strength of this association was similar for men age ≥50 yr (odds ratio = 2.11, 95% confidence interval = 1.62-2.74). In men age < 50 yr, the composite strength threshold associated with MetS was 2.57 kg·kg body weight, whereas in men age ≥ 50 yr the threshold was 2.35 kg·kg body weight. This study is the first to identify a threshold of muscle strength associated with an increased likelihood of MetS in men. Measures of muscle strength may help identify men at risk of chronic disease.

  9. A NEW CLINICAL MUSCLE FUNCTION TEST FOR ASSESSMENT OF HIP EXTERNAL ROTATION STRENGTH: AUGUSTSSON STRENGTH TEST.

    PubMed

    Augustsson, Jesper

    2016-08-01

    Dynamic clinical tests of hip strength applicable on patients, non-athletes and athletes alike, are lacking. The aim of this study was therefore to develop and evaluate the reliability of a dynamic muscle function test of hip external rotation strength, using a novel device. A second aim was to determine if gender differences exist in absolute and relative hip strength using the new test. Fifty-three healthy sport science students (34 women and 19 men) were tested for hip external rotation strength using a device that consisted of a strap connected in series with an elastic resistance band loop, and a measuring tape connected in parallel with the elastic resistance band. The test was carried out with the subject side lying, positioned in 45 ° of hip flexion and the knees flexed to 90 ° with the device firmly fastened proximally across the knees. The subject then exerted maximal concentric hip external rotation force against the device thereby extending the elastic resistance band. The displacement achieved by the subject was documented by the tape measure and the corresponding force production was calculated. Both right and left hip strength was measured. Fifteen of the subjects were tested on repeated occasions to evaluate test-retest reliability. No significant test-retest differences were observed. Intra-class correlation coefficients ranged 0.93-0.94 and coefficients of variation 2.76-4.60%. In absolute values, men were significantly stronger in hip external rotation than women (right side 13.2 vs 11.0 kg, p = 0.001, left side 13.2 vs 11.5 kg, p = 0.002). There were no significant differences in hip external rotation strength normalized for body weight (BW) between men and women (right side 0.17 kg/BW vs 0.17 kg/BW, p = 0.675, left side 0.17 kg/BW vs 0.18 kg/BW, p = 0.156). The new muscle function test showed high reliability and thus could be useful for measuring dynamic hip external rotation strength in patients, non-athletes and athletes

  10. Relationship Between Muscle Strength Asymmetry and Body Sway in Older Adults.

    PubMed

    Koda, Hitoshi; Kai, Yoshihiro; Murata, Shin; Osugi, Hironori; Anami, Kunihiko; Fukumoto, Takahiko; Imagita, Hidetaka

    2018-05-31

    The purpose of this study was to investigate the relationship between muscle strength asymmetry and body sway while walking. We studied 63 older adult women. Strong side and weak side of knee extension strength, toe grip strength, hand grip strength, and body sway while walking were measured. The relationship between muscle strength asymmetry for each muscle and body sway while walking was evaluated using Pearson's correlation coefficient. Regarding the muscles recognized to have significant correlation with body sway, the asymmetry cutoff value causing an increased sway was calculated. Toe grip strength asymmetry was significantly correlated with body sway. Toe grip strength asymmetry causing an increased body sway had a cutoff value of 23.5%. Our findings suggest toe grip strength asymmetry may be a target for improving gait stability.

  11. The variation of the strength of neck extensor muscles and semispinalis capitis muscle size with head and neck position.

    PubMed

    Rezasoltani, A; Nasiri, R; Faizei, A M; Zaafari, G; Mirshahvelayati, A S; Bakhshidarabad, L

    2013-04-01

    Semispinalis capitis muscle (SECM) is a massive and long cervico-thoracic muscle which functions as a main head and neck extensor muscle. The aim of this study was to detect the effect of head and neck positions on the strength of neck extensor muscles and size of SECM in healthy subjects. Thirty healthy women students voluntarily participated in this study. An ultrasonography apparatus (Hitachi EUB 525) and a system of tension-meter were used to scan the right SECM at the level of third cervical spine and to measure the strength of neck extensor muscles at three head and neck positions. Neck extensor muscles were stronger in neutral than flexion or than extension positions while the size of SECM was larger in extension than neutral or than flexion position. The force generation capacity of the main neck extensor muscle was lower at two head and neck flexion and extension positions than neutral position. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. The effectiveness of a single session of Whole-Body Vibration in improving the balance and the strength in type 2 diabetic patients with mild to moderate degree of peripheral neuropathy: a pilot study.

    PubMed

    Kordi Yoosefinejad, Amin; Shadmehr, Azadeh; Olyaei, Ghloamreza; Talebian, Saeed; Bagheri, Hossein

    2014-01-01

    Peripheral neuropathy is a common complication of diabetes mellitus. Muscle strength and the balance deficits are seen in these patients. Whole-Body Vibration (WBV) is a time-efficient method which may be beneficial for them. The immediate effects of WBV on muscle strength and balance have not been studied yet. The aim of this study was to investigate the effects of one session of WBV on muscle strength and the balance of diabetic patients. Ten diabetic patients with peripheral neuropathy took part in this study. Outcome measurements were total strength, strength of tibialis anterior and quadriceps femoris muscles and the balance parameters including Unilateral Stance Test and Timed Up and Go Test. Tibialis anterior muscle strength and Timed Up and GO Test parameters showed significant differences post-exercise in comparison to baseline. A session of WBV had positive effects on muscle strength and the balance in patients with type-2 diabetes associated with neuropathy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Investigation of the effect of changes in muscle strength in gestational age upon fear of falling and quality of life.

    PubMed

    Atay, Emrah; Başalan Iz, Fatma

    2015-01-01

    The aim of this study is the investigation of the effect of changes in muscle strength in gestational age upon fear of falling and quality of life. This longitudinal, descriptive study included a sample of 37 pregnant women who volunteered to participate. The research data were collected at 20 and 32 weeks of gestation. Data collection instruments included a newly developed questionnaire form, the Tinetti Falls Efficacy Scale, a visual analog scale, and the Turkish language version of the WHO Quality of Life Scale. Upper body flexibility was measured by the back scratch test, while muscle strength was measured by a handgrip dynamometer and balance by the unipedal stance test. It was found that, as pregnancy advanced, pregnant women had an increased fear of falling, as well as elevated systolic and diastolic blood pressure levels. Participants suffered significant impairments in their balance, handgrip strength, and quality of life within the physical, psychological, and environmental domains. As pregnancy advances, muscle strength decreases and the fear of falling experienced by pregnant women increases, which significantly impairs the quality of life in the domains of environment, physical, and mental health.

  14. Effects of Strength Training Using Unstable Surfaces on Strength, Power and Balance Performance Across the Lifespan: A Systematic Review and Meta-analysis.

    PubMed

    Behm, David G; Muehlbauer, Thomas; Kibele, Armin; Granacher, Urs

    2015-12-01

    The effectiveness of strength training on unstable surfaces (STU) versus stable surfaces (STS) or a control condition (CON; i.e., no training or regular training only) for strength, power and balance performance across the lifespan has not yet been investigated in a systematic review and meta-analysis. The aims of this systematic review and meta-analysis were to determine the general effects of STU versus STS or CON on muscle strength, power and balance in healthy individuals across the lifespan and to investigate whether performance changes following STU are age specific. A computerized systematic literature search was performed in the electronic databases PubMed and Web of Science from January 1984 up to February 2015. Initially, 209 articles were identified for review. Only controlled trials were included if they investigated STU in healthy individuals and tested at least one measure of maximal strength, strength endurance, muscle power, or static/dynamic balance. In total, 22 studies met the inclusion criteria. The included studies were coded for the following criteria: age, sex, training status, training modality, exercise and test modality. Effect size measures included within-subject standardized mean differences (SMDw) and weighted between-subject standardized mean differences (SMDb). Heterogeneity between studies was assessed using I2 and χ2 statistics. The methodological quality of each study was assessed using the Physiotherapy Evidence Database (PEDro) Scale. Our search failed to identify studies that examined the effects of STU versus STS or CON in children and middle-aged adults. However, four studies were identified that investigated the effects of STU versus CON or STS in adolescents, 15 studies were identified in young adults and three studies were identified in old adults. Compared with CON, STU produced medium effects on maximal strength in young adults and no effects to medium effects in old adults. In addition, large effects were detected on

  15. Alfacalcidol improves muscle power, muscle function and balance in elderly patients with reduced bone mass.

    PubMed

    Schacht, E; Ringe, Johann D

    2012-01-01

    We investigated the effect of daily therapy with 1 mcg alfacalcidol (Doss(®)-TEVA/AWD-pharma) on muscle power, muscle function, balance performance and fear of falls in an open, multi-centered, uncontrolled, prospective study on a cohort of patients with reduced bone mass. Among the 2,097 participants, 87.1% were post-menopausal women and 12.9% were men. Mean age was 74.8 years and mean body mass index (BMI) 26.3 kg/m². A total of 75.3% of the study population had osteoporosis, 81% a diagnosis of "increased risk of falls" and 70.1% had a creatinine clearance (CrCl) of <65 ml/min. Participants underwent muscle function and muscle power tests at onset and after 3 and 6 months: the timed up and go test (TUG) and the chair rising test (CRT). At baseline and after 6 months, participants performed the tandem gait test (TGT) and filled out a questionnaire evaluating fear of falling. Successful performance in the muscle tests is associated with a significantly lower risk of falls and non-vertebral fractures in elderly patients (successful test performance: TUG ≤ 10 s (sec), CRT ≤ 10 s, TGT ≥ 8 steps). A significant improvement in the performance of the two muscle tests was proved already after 3 months of treatment with alfacalcidol and further increased by the end of the therapeutic intervention. There were significant increases in the number of participants able to successfully perform the tests: 24.6% at baseline and 46.3% at the end of trial for the TUG (P < 0.0001) and 21.7% at baseline and 44.2% at the end for the CRT test (P = 0.0001). The mean time used for the TUG was decreased by 3.0 s from the average onset value of 17.0 s and by 3.1 s from the initial average 16.5 s for the CRT. The percentage of participants able to perform the balance test (TGT) increased from 36.0% at onset to 58.6% at the end of the trial (P < 0.0001). An increased fear of falling was reduced by the end of the study in 74.4% of the patients. Throughout the study, there were 26

  16. A longitudinal study of muscle strength and function in patients with cancer cachexia.

    PubMed

    Gale, Nichola; Wasley, David; Roberts, Sioned; Backx, Karianne; Nelson, Annemarie; van Deursen, Robert; Byrne, Anthony

    2018-06-02

    Patients with cancer frequently experience an involuntary loss of weight (in particular loss of muscle mass), defined as cachexia, with profound implications for independence and quality of life. The rate at which such patients' physical performance declines has not been well established. The aim of this study was to determine the change in muscle strength and function over 8 weeks in patients with already established cancer cachexia, to help inform the design and duration of physical activity interventions applicable to this patient group. Patients with thoracic and gastrointestinal cancer and with unintentional weight loss of > 5% in 6 months or BMI < 20 plus 2% weight loss were included. Physical and functional assessments (baseline, 4 weeks, 8 weeks) included isometric quadriceps and hamstring strength, handgrip, standing balance, 10-m walk time and timed up and go. Fifty patients (32 male), mean ± SD age 65 ± 10 years and BMI 24.9 ± 4.3 kg/m 2 , were recruited. Thoracic cancer patients had lower muscle strength and function (p < 0.05). Despite notable attrition, in patients who completed all assessments (8 thoracic and 12 gastrointestinal), there was little change in performance over 8 weeks (p > 0.05). Baseline variables did not differentiate between completers and non-completers (p > 0.05). More than a third of patients with established cancer cachexia in our study were stable over 8 weeks, suggesting a subgroup who may benefit from targeted interventions of reasonable duration. Better understanding the physical performance parameters which characterise and differentiate these patients has important clinical implications for cancer multidisciplinary team practice.

  17. Effect of low-cost resistance training on lower-limb strength and balance in institutionalized seniors.

    PubMed

    Motalebi, Seyedeh Ameneh; Cheong, Loke Seng; Iranagh, Jamileh Amirzadeh; Mohammadi, Fatemeh

    2018-01-01

    Background/Study Context: Given the rapid increase in the aging population worldwide, fall prevention is of utmost importance. It is essential to establish an efficient, simple, safe, and low-cost intervention method for reducing the risk of falls. This study examined the effect of 12 weeks of progressive elastic resistance training on lower-limb muscle strength and balance in seniors living in the Rumah Seri Kenangan, social welfare home in Cheras, Malaysia. A total of 51 subjects qualified to take part in this quasi-experimental study. They were assigned to either the resistance exercise group (n = 26) or control group (n = 25). The mean age of the 45 participants who completed the program was 70.7 (SD = 6.6). The exercise group met twice per week and performing one to three sets of 8 to 10 repetitions for each of nine lower-limb elastic resistance exercises. All exercises were conducted at low to moderate intensities in sitting or standing positions. The subjects were tested at baseline and 6 and 12 weeks into the program. The results showed statistically significant improvements in lower-limb muscle strength as measured by five times sit-to-stand test (%Δ = 22.6) and dynamic balance quantified by the timed up-and-go test (%Δ = 18.7), four-square step test (%Δ = 14.67), and step test for the right (%Δ = 18.36) and left (%Δ = 18.80) legs. No significant changes were observed in static balance as measured using the tandem stand test (%Δ = 3.25), and one-leg stand test with eyes opened (%Δ = 9.58) and eyes closed (%Δ = -0.61) after completion of the program. The findings support the feasibility and efficacy of a simple and inexpensive resistance training program to improve lower-limb muscle strength and dynamic balance among the institutionalized older adults.

  18. Inline skating for balance and strength promotion in children during physical education.

    PubMed

    Muehlbauer, Thomas; Kuehnen, Matthias; Granacher, Urs

    2013-12-01

    Deficiencies in balance and strength are common in children and they may lead to injuries. This study investigated the effects of inline skating exercise on balance and strength performance in healthy children. Twenty 11-12-year-old children (8 girls, 12 boys) were assigned to an intervention (n = 10) or a control (n = 10) group. Participants in the intervention group underwent a 4-week inline skating program (2 times/week, 90 min. each) integrated in their physical education lessons. Balance and strength were measured using the Star Excursion Balance test and the countermovement jump test. As compared to the control group, the intervention group significantly improved balance (17-48%, Cohen's d = 0.00-1.49) and jump height (8%, Cohen's d = 0.48). In children, inline skating is a safe, feasible (90% adherence rate), and effective program that can be integrated in physical education lessons to promote balance and strength.

  19. Impact on nutrition on muscle strength and performance in older adults

    USDA-ARS?s Scientific Manuscript database

    Muscle strength plays an important role in determining risk for falls, which result in fractures and other injuries. While bone loss has long been recognized as an inevitable consequence of aging, sarcopenia-the gradual loss of skeletal muscle mass and strength that occurs with advancing age-has rec...

  20. Do muscle mass, muscle density, strength, and physical function similarly influence risk of hospitalization in older adults?

    PubMed

    Cawthon, Peggy Mannen; Fox, Kathleen M; Gandra, Shravanthi R; Delmonico, Matthew J; Chiou, Chiun-Fang; Anthony, Mary S; Sewall, Ase; Goodpaster, Bret; Satterfield, Suzanne; Cummings, Steven R; Harris, Tamara B

    2009-08-01

    To examine the association between strength, function, lean mass, muscle density, and risk of hospitalization. Prospective cohort study. Two U.S. clinical centers. Adults aged 70 to 80 (N=3,011) from the Health, Aging and Body Composition Study. Measurements were of grip strength, knee extension strength, lean mass, walking speed, and chair stand pace. Thigh computed tomography scans assessed muscle area and density (a proxy for muscle fat infiltration). Hospitalizations were confirmed by local review of medical records. Negative binomial regression models estimated incident rate ratios (IRRs) of hospitalization for race- and sex-specific quartiles of each muscle and function parameter separately. Multivariate models adjusted for age, body mass index, health status, and coexisting medical conditions. During an average 4.7 years of follow-up, 1,678 (55.7%) participants experienced one or more hospitalizations. Participants in the lowest quartile of muscle density were more likely to be subsequently hospitalized (multivariate IRR=1.47, 95% confidence interval (CI)=1.24-1.73) than those in the highest quartile. Similarly, participants with the weakest grip strength were at greater risk of hospitalization (multivariate IRR=1.52, 95% CI=1.30-1.78, Q1 vs. Q4). Comparable results were seen for knee strength, walking pace, and chair stands pace. Lean mass and muscle area were not associated with risk of hospitalization. Weak strength, poor function, and low muscle density, but not muscle size or lean mass, were associated with greater risk of hospitalization. Interventions to reduce the disease burden associated with sarcopenia should focus on increasing muscle strength and improving physical function rather than simply increasing lean mass.

  1. Effect of strength training on regional hypertrophy of the elbow flexor muscles.

    PubMed

    Drummond, Marcos D M; Szmuchrowski, Leszek A; Goulart, Karine N O; Couto, Bruno P

    2016-10-01

    Muscle hypertrophy is the main structural adaptation to strength training. We investigated the chronic effects of strength training on muscle hypertrophy in different regions of the elbow flexor muscles. Eleven untrained men (21.8 ± 1.62 years) underwent magnetic resonance imaging to determine the proximal, medial, distal, and mean cross-sectional areas (CSA) of the elbow flexors. The volunteers completed 12 weeks of strength training. The training protocol consisted of 4 sets of 8-10 maximum repetitions of unilateral elbow flexion. The interval between sets was 120 s. The training frequency was 3 sessions per week. The magnetic resonance images verified the presence of significant and similar hypertrophy in the distal, medial, and proximal portions of the elbow flexor muscles. Muscle hypertrophy may be assessed using only the medial CSA. We should not expect different degrees of hypertrophy among the regions of the elbow flexor muscles. Muscle Nerve 54: 750-755, 2016. © 2016 Wiley Periodicals, Inc.

  2. Leg and trunk muscle coordination and postural sway during increasingly difficult standing balance tasks in young and older adults.

    PubMed

    Donath, Lars; Kurz, Eduard; Roth, Ralf; Zahner, Lukas; Faude, Oliver

    2016-09-01

    Ageing impairs body balance and increases older adults' fall risk. Balance training can improve intrinsic fall risk factors. However, age comparisons of muscle activity responses during balance tasks are lacking. This study investigated relative muscle activity, muscle coordination and postural sway during various recommended static balance training tasks. Muscle activity (%MVC), amplitude ratios (AR) and co-activity (CAI) were determined during standing tasks for 30s (1: double limb stance on a foam surface, eyes open; 2: double limb stance on firm ground, eyes closed; 3: double limb stance, feet in step position on a foam surface, eyes open; 4: double limb stance, feet in step position on firm ground, eyes closed; 5: single limb stance on firm ground, eyes open) in 20 healthy young adults (24±2 y) and 20 older adults (73±6 y). Surface electromyography (SEMG) was applied (SENIAM guidelines) to ankle (tibialis anterior, soleus, medial gastrocnemius, peroneus longus) and thigh (vastus lateralis, vastus medialis, biceps femoris, semitendinosus) muscles (non-dominant leg). Electrodes over trunk (multifidus and internal oblique) muscles were applied bilaterally. Two- to six-fold higher levels of relative muscle activity were found in older adults for ankle (0.0002muscles. Co-activation was elevated in young adults for the trunk (0.001muscle coordination patterns during all stance conditions at the ankle (0.06<ηp(2)<0.28) and the trunk (0.14<ηp(2)<0.23). Older adults had higher electrophysiological costs for all stance conditions. Muscle coordination showed inverse activity patterns at the ankle and trunk. Optimal balance and strength training programs should take into account age-specific alterations in muscle activity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Muscle strength and kinetic gait pattern in children with bilateral spastic CP.

    PubMed

    Eek, Meta Nyström; Tranberg, Roy; Beckung, Eva

    2011-03-01

    Cerebral palsy is often associated with an abnormal gait pattern. This study put focus on relation between muscle strength and kinetic gait pattern in children with bilateral spastic cerebral palsy and compares them with a reference group. In total 20 children with CP and 20 typically developing children participated. They were all assessed with measurement of muscle strength in eight muscle groups in the legs and a 3-dimensional gait analysis including force data. It was found that children with CP were not only significantly weaker in all muscle groups but also walked with slower velocity and shorter stride length when compared with the reference group. Gait moments differed at the ankle level with significantly lower moments in children with CP. Gait moments were closer to the maximal muscle strength in the group of children with CP. Furthermore a correlation between plantarflexing gait moment and muscle strength was observed in six of the eight muscle groups in children with CP, a relation not found in the reference group. A similar pattern was seen between muscle strength and generating ankle power with a rho=0.582-0.766. The results of this study state the importance of the relationship of the overall muscle strength pattern in the lower extremity, not only the plantarflexors. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Effect of mirror use on lower extremity muscle strength of patients with chronic stroke.

    PubMed

    Kim, Myoung-Kwon; Choe, Yu-Won; Shin, Young-Jun; Peng, Cheng; Choi, Eun-Hong

    2018-02-01

    [Purpose] This study examines the effect on muscle strength of lower extremity muscle strength exercise while using a mirror on the non-paretic side in patients with chronic stroke. [Subjects and Methods] Subjects were randomly assigned to a non-mirror lower extremity exercise group (n=10), a mirror lower extremity exercise group (n=10), or a mirror lower extremity muscle strength exercise group (n=10). Subjects were asked to do the exercise assigned to their group (5 sets 30 times a day, 5 times weekly for 4 weeks) with general physical therapy in the hospital. Muscle strength in the knee extensor and flexor of paretic and non-paretic side were measured using electrical muscle testing device before and after the intervention. [Results] Muscle strength significantly increased within each group after intervention. No significant differences were found among the three groups. [Conclusion] This study showed that the lower extremity muscle strength exercise of the non-paretic side using a mirror has a positive effect on muscle strength in patient with chronic stroke.

  5. Relative strengths of the calf muscles based on MRI volume measurements.

    PubMed

    Jeng, Clifford L; Thawait, Gaurav K; Kwon, John Y; Machado, Antonio; Boyle, James W; Campbell, John; Carrino, John A

    2012-05-01

    In 1985, Silver et al. published a cadaver study which determined the relative order of strength of the muscles in the calf. Muscle strength, which is proportional to volume, was obtained by dissecting out the individual muscles, weighing them, and then multiplying by the specific gravity. No similar studies have been performed using {\\it in vivo} measurements of muscle volume. Ten normal subjects underwent 3-Tesla MRI's of both lower extremities using non-fat-saturated T2 SPACE sequences. The volume for each muscle was determined by tracing the muscle contour on sequential axial images and then interpolating the volume using imaging software. The results from this study differ from Silver's original article. The lateral head of the gastrocnemius was found to be stronger than the tibialis anterior muscle. The FHL and EDL muscles were both stronger than the peroneus longus. There was no significant difference in strength between the peroneus longus and brevis muscles. This revised order of muscle strengths in the calf based on in vivo MRI findings may assist surgeons in determining the optimal tendons to transfer in order to address muscle weakness and deformity.

  6. Measures of static postural control moderate the association of strength and power with functional dynamic balance.

    PubMed

    Forte, Roberta; Boreham, Colin A G; De Vito, Giuseppe; Ditroilo, Massimiliano; Pesce, Caterina

    2014-12-01

    Age-related reductions in strength and power are considered to negatively impact balance control, but the existence of a direct association is still an issue of debate. This is possibly due to the fact that balance assessment is complex, reflects different underlying physiologic mechanisms and involves quantitative measurements of postural sway or timing of performance during balance tasks. The present study evaluated the moderator effect of static postural control on the association of power and strength with dynamic balance tasks. Fifty-seven healthy 65-75 year old individuals performed tests of dynamic functional balance (walking speed under different conditions) and of strength, power and static postural control. Dynamic balance performance (walking speed) was associated with lower limb strength and power, as well as postural control under conditions requiring postural adjustments (narrow surface walking r(2) = 0.31, p < 0.001). An interaction effect between strength and static postural control was found with narrow surface walking and talking while walking (change of β 0.980, p < 0.001 in strength for 1 SD improvements in static postural control for narrow walking, and [Formula: see text] -0.730, p < 0.01 in talking while walking). These results indicate that good static postural control facilitates the utilisation of lower limb strength to better perform complex, dynamic functional balance tasks. Practical implications for assessment and training are discussed.

  7. Muscle strength in patients with acromegaly at diagnosis and during long-term follow-up.

    PubMed

    Füchtbauer, Laila; Olsson, Daniel S; Bengtsson, Bengt-Åke; Norrman, Lise-Lott; Sunnerhagen, Katharina S; Johannsson, Gudmundur

    2017-08-01

    Patients with acromegaly have decreased body fat (BF) and increased extracellular water (ECW) and muscle mass. Although there is a lack of systematic studies on muscle function, it is believed that patients with acromegaly may suffer from proximal muscle weakness despite their increased muscle mass. We studied body composition and muscle function in untreated acromegaly and after biochemical remission. Prospective observational study. Patients with acromegaly underwent measurements of muscle strength (dynamometers) and body composition (four-compartment model) at diagnosis ( n  = 48), 1 year after surgery ( n  = 29) and after long-term follow-up (median 11 years) ( n  = 24). Results were compared to healthy subjects. Untreated patients had increased body cell mass (113 ± 9% of predicted) and ECW (110 ± 20%) and decreased BF (67 ± 7.6%). At one-year follow-up, serum concentration of IGF-I was reduced and body composition had normalized. At baseline, isometric muscle strength in knee flexors and extensors was normal and concentric strength was modestly increased whereas grip strength and endurance was reduced. After one year, muscle strength was normal in both patients with still active disease and patients in remission. At long-term follow-up, all patients were in remission. Most muscle function tests remained normal, but isometric flexion and the fatigue index were increased to 153 ± 42% and 139 ± 28% of predicted values, respectively. Patients with untreated acromegaly had increased body cell mass and normal or modestly increased proximal muscle strength, whereas their grip strength was reduced. After biochemical improvement and remission, body composition was normalized, hand grip strength was increased, whereas proximal muscle fatigue increased. © 2017 European Society of Endocrinology.

  8. Strength and Power Training Effects on Lower Limb Force, Functional Capacity, and Static and Dynamic Balance in Older Female Adults.

    PubMed

    Lopes, Paula Born; Pereira, Gleber; Lodovico, Angélica; Bento, Paulo C B; Rodacki, André L F

    2016-03-03

    It has been proposed that muscle power is more effective to prevent falls than muscle force production capacity, as rapid reactions are required to allow the postural control. This study aimed to compare the effects of strength and power training on lower limb force, functional capacity, and static and dynamic balance in older female adults. Thirty-seven volunteered healthy women had been allocated into the strength-training group (n = 14; 69 ± 7.3 years, 155 ± 5.6 cm, 72 ± 9.7 kg), the power-training group (n = 12; 67 ± 7.4 years, 153 ± 5.5 cm, 67.2 ± 7 kg), and control group (n = 11; 65 ± 3.1 years, 154 ± 5.6 cm, 70.9 ± 3 kg). After 12 weeks of training, the strength-training and power-training groups increased significantly maximum dynamic strength (29% and 27%), isometric strength (26% and 37%), and step total time (13% and 14%, dynamic balance), respectively. However, only the power-training group increased the rate of torque development (55%) and the functional capacity in 30-second chair stand (22%) and in time up and go tests (-10%). Empirically, power training may reduce the risk of injuries due to lower loads compared to strength training, and consequently, the physical effort demand during the training session is lower. Therefore, power training should be recommended as attractive training stimuli to improve lower limb force, functional capacity, and postural control of older female adults.

  9. Relationship between muscle mass and physical performance: is it the same in older adults with weak muscle strength?

    PubMed

    Kim, Kyoung-Eun; Jang, Soong-Nang; Lim, Soo; Park, Young Joo; Paik, Nam-Jong; Kim, Ki Woong; Jang, Hak Chul; Lim, Jae-Young

    2012-11-01

    the relationship between muscle mass and physical performance has not been consistent among studies. to clarify the relationship between muscle mass and physical performance in older adults with weak muscle strength. cross-sectional analysis using the baseline data of 542 older men and women from the Korean Longitudinal Study on Health and Aging. dual X-ray absorptiometry, isokinetic dynamometer and the Short Physical Performance Battery (SPPB) were performed. Two muscle mass parameters, appendicular skeletal mass divided by weight (ASM/Wt) and by height squared (ASM/Ht(2)), were measured. We divided the participants into a lower-quartile (L25) group and an upper-three-quartiles (H75) group based on the knee-extensor peak torque. Correlation analysis and logistic regression models were used to assess the association between muscle mass and low physical performance, defined as SPPB scores <9, after controlling for confounders. in the L25 group, no correlation between mass and SPPB was detected, whereas the correlation between peak torque and SPPB was significant and higher than that in the H75 group. Results from the logistic models also showed no association between muscle mass and SPPB in the L25 group, whereas muscle mass was associated with SPPB in the H75 group. muscle mass was not associated with physical performance in weak older adults. Measures of muscle strength may be of greater clinical importance in weak older adults than is muscle mass per se.

  10. Muscle strength response to strength training is influenced by insulin-like growth factor 1 genotype in older adults.

    PubMed

    Kostek, Matthew C; Delmonico, Matthew J; Reichel, Jonathan B; Roth, Stephen M; Douglass, Larry; Ferrell, Robert E; Hurley, Ben F

    2005-06-01

    Strength training (ST) is considered an intervention of choice for the prevention and treatment of sarcopenia. Reports in the literature have suggested that the insulin-like growth factor I protein (IGF-I) plays a major role in ST-induced skeletal muscle hypertrophy and strength improvements. A microsatellite repeat in the promoter region of the IGF1 gene has been associated with IGF-I blood levels and phenotypes related to IGF-I in adult men and women. To examine the influence of this polymorphism on muscle hypertrophic and strength responses to ST, we studied 67 Caucasian men and women before and after a 10-wk single-leg knee-extension ST program. One repetition maximum strength, muscle volume via computed tomography, and muscle quality were assessed at baseline and after 10 wk of training. The IGF1 repeat promoter polymorphism and three single-nucleotide polymorphisms were genotyped. For the promoter polymorphism, subjects were grouped as homozygous for the 192 allele, heterozygous, or noncarriers of the 192 allele. After 10 wk of training, 1-repetition maximum, muscle volume, and muscle quality increased significantly for all groups combined (P < 0.001). However, carriers of the 192 allele gained significantly more strength with ST than noncarriers of the 192 allele (P = 0.02). There was also a nonsignificant trend for a greater increase in muscle volume in 192 carriers than noncarriers (P = 0.08). No significant associations were observed for the other polymorphisms studied. Thus these data suggest that the IGF1 promoter polymorphism may influence the strength response to ST. Larger sample sizes should be used in future studies to verify these results.

  11. Muscle Strength Is Protective Against Osteoporosis in an Ethnically Diverse Sample of Adults.

    PubMed

    McGrath, Ryan P; Kraemer, William J; Vincent, Brenda M; Hall, Orman T; Peterson, Mark D

    2017-09-01

    McGrath, RP, Kraemer, WJ, Vincent, BM, Hall, OT, and Peterson, MD. Muscle strength is protective against osteoporosis in an ethnically diverse sample of adults. J Strength Cond Res 31(9): 2586-2589, 2017-The odds of developing osteoporosis may be affected by modifiable and nonmodifiable factors such as muscle strength and ethnicity. This study sought to (a) determine whether increased muscle strength was associated with decreased odds of osteoporosis and (b) identify whether the odds of osteoporosis differed by ethnicity. Data from the 2013 to 2014 National Health and Nutrition Examination Survey were analyzed. Muscle strength was measured with a hand-held dynamometer, and dual-energy x-ray absorptiometry was used to assess femoral neck bone mineral density. A T-score of ≤2.5 was used to define osteoporosis. Separate covariate-adjusted logistic regression models were performed on each sex to determine the association between muscle strength and osteoporosis. Odds ratios (ORs) were also generated to identify if the association between muscle strength and osteoporosis differed by ethnicity using non-Hispanic blacks as the reference group. There were 2,861 participants included. Muscle strength was shown to be protective against osteoporosis for men (OR: 0.94; 95% confidence interval [CI]: 0.94-0.94) and women (OR: 0.90; CI: 0.90-0.90). Although ORs varied across ethnicities, non-Hispanic Asian men (OR: 6.62; CI: 6.51-6.72) and women (OR: 6.42; CI: 6.37-6.48) were at highest odds of osteoporosis. Increased muscle strength reduced the odds of osteoporosis among both men and women in a nationally representative, ethnically diverse sample of adults. Non-Hispanic Asians had the highest odds of developing osteoporosis. Irrespective of sex or ethnicity, increased muscle strength may help protect against the odds of developing osteoporosis.

  12. Quantitative MRI and strength measurements in the assessment of muscle quality in Duchenne muscular dystrophy.

    PubMed

    Wokke, B H; van den Bergen, J C; Versluis, M J; Niks, E H; Milles, J; Webb, A G; van Zwet, E W; Aartsma-Rus, A; Verschuuren, J J; Kan, H E

    2014-05-01

    The purpose of this study was to assess leg muscle quality and give a detailed description of leg muscle involvement in a series of Duchenne muscular dystrophy patients using quantitative MRI and strength measurements. Fatty infiltration, as well as total and contractile (not fatty infiltrated) cross sectional areas of various leg muscles were determined in 16 Duchenne patients and 11 controls (aged 8-15). To determine specific muscle strength, four leg muscle groups (quadriceps femoris, hamstrings, anterior tibialis and triceps surae) were measured and related to the amount of contractile tissue. In patients, the quadriceps femoris showed decreased total and contractile cross sectional area, attributable to muscle atrophy. The total, but not the contractile, cross sectional area of the triceps surae was increased in patients, corresponding to hypertrophy. Specific strength decreased in all four muscle groups of Duchenne patients, indicating reduced muscle quality. This suggests that muscle hypertrophy and fatty infiltration are two distinct pathological processes, differing between muscle groups. Additionally, the quality of remaining muscle fibers is severely reduced in the legs of Duchenne patients. The combination of quantitative MRI and quantitative muscle testing could be a valuable outcome parameter in longitudinal studies and in the follow-up of therapeutic effects. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Respiratory muscle training with enzyme replacement therapy improves muscle strength in late - onset Pompe disease.

    PubMed

    Jevnikar, Mitja; Kodric, Metka; Cantarutti, Fabiana; Cifaldi, Rossella; Longo, Cinzia; Della Porta, Rossana; Bembi, Bruno; Confalonieri, Marco

    2015-12-01

    Pompe disease is an autosomal recessive metabolic disorder caused by the deficiency of the lysosomal enzyme acid α-glucosidase. This deficiency leads to glycogen accumulation in the lysosomes of muscle tissue causing progressive muscular weakness particularly of the respiratory system. Enzyme replacement therapy (ERT) has demonstrated efficacy in slowing down disease progression in infants. Despite the large number of studies describing the effects of physical training in juvenile and adult late onset Pompe disease (LOPD). There are very few reports that analyze the benefits of respiratory muscle rehabilitation or training. The effectiveness of respiratory muscle training was investigated using a specific appliance with adjustable resistance (Threshold). The primary endpoint was effect on respiratory muscular strength by measurements of MIP and MEP. Eight late-onset Pompe patients (aged 13 to 58 years; 4 female, 4 male) with respiratory muscle deficiency on functional respiratory tests were studied. All patients received ERT at the dosage of 20 mg/kg/every 2 weeks and underwent training with Threshold at specified pressures for 24 months. A significant increase in MIP was observed during the follow-up of 24 month: 39.6 cm H 2 O (+ 25.0%) at month 3; 39.5 cm H 2 O (+ 24.9%) at month 6; 39.1 cm H 2 O (+ 23.7%) at month 9; 37.3 cm H 2 O (+ 18.2%) at month 12; and 37.3 cm H 2 O (+ 17.8%) at month 24. Median MEP values also showed a significant increase during the first 9 months: 29.8 cm H 2 O, (+ 14.3%) at month 3; 31.0 cm H 2 O (+ 18.6) at month 6; and 29.5 cm H 2 O (+ 12.9) at month 9. MEP was then shown to be decreased at months 12 and 24; median MEP was 27.2 cm H 2 O (+ 4.3%) at 12 months and 26.6 cm H 2 O (+ 1.9%) at 24 months. The FVC remain stable throughout the study. An increase in respiratory muscular strength was demonstrated with Threshold training when used in combination with ERT.

  14. Soccer-Specific Fatigue and Eccentric Hamstrings Muscle Strength

    PubMed Central

    Greig, Matt; Siegler, Jason C

    2009-01-01

    Context: Epidemiologic findings of higher incidences of hamstrings muscle strains during the latter stages of soccer match play have been attributed to fatigue. Objective: To investigate the influence of soccer-specific fatigue on the peak eccentric torque of the knee flexor muscles. Design: Descriptive laboratory study. Setting: Controlled laboratory environment. Patients or Other Participants: Ten male professional soccer players (age  =  24.7 ± 4.4 years, mass  =  77.1 ± 8.3 kg, V̇o2max  =  63.0 ± 4.8 mL·kg−1·min−1). Intervention(s): Participants completed an intermittent treadmill protocol replicating the activity profile of soccer match play, with a passive halftime interval. Before exercise and at 15-minute intervals, each player completed isokinetic dynamometer trials. Main Outcome Measure(s): Peak eccentric knee flexor torque was quantified at isokinetic speeds of 180° · s−1, 300° · s−1, and 60° · s−1, with 5 repetitions at each speed. Results: Peak eccentric knee flexor torque at the end of the game (T300eccH105  =  127 ± 25 Nm) and at the end of the passive halftime interval (T300eccH60  =  133 ± 32 Nm) was reduced relative to T300eccH00 (167 ± 35 Nm, P < .01) and T300eccH15 (161 ± 35 Nm, P  =  .02). Conclusions: Eccentric hamstrings strength decreased as a function of time and after the halftime interval. This finding indicates a greater risk of injuries at these specific times, especially for explosive movements, in accordance with epidemiologic observations. Incorporating eccentric knee flexor exercises into resistance training sessions that follow soccer-specific conditioning is warranted to try to reduce the incidence or recurrence of hamstrings strains. PMID:19295963

  15. Respiratory muscle strength is not decreased in patients undergoing cardiac surgery.

    PubMed

    Urell, Charlotte; Emtner, Margareta; Hedenstrom, Hans; Westerdahl, Elisabeth

    2016-03-31

    Postoperative pulmonary impairments are significant complications after cardiac surgery. Decreased respiratory muscle strength could be one reason for impaired lung function in the postoperative period. The primary aim of this study was to describe respiratory muscle strength before and two months after cardiac surgery. A secondary aim was to describe possible associations between respiratory muscle strength and lung function. In this prospective observational study 36 adult cardiac surgery patients (67 ± 10 years) were studied. Respiratory muscle strength and lung function were measured before and two months after surgery. Pre- and postoperative respiratory muscle strength was in accordance with predicted values; MIP was 78 ± 24 cmH2O preoperatively and 73 ± 22 cmH2O at two months follow-up (p = 0.19). MEP was 122 ± 33 cmH2O preoperatively and 115 ± 38 cmH2O at two months follow-up (p = 0.18). Preoperative lung function was in accordance with predicted values, but was significantly decreased postoperatively. At two-months follow-up there was a moderate correlation between MIP and FEV1 (r = 0.43, p = 0.009). Respiratory muscle strength was not impaired, either before or two months after cardiac surgery. The reason for postoperative lung function alteration is not yet known. Interventions aimed at restore an optimal postoperative lung function should focus on other interventions then respiratory muscle strength training.

  16. Isometric hand grip strength measured by the Nintendo Wii Balance Board - a reliable new method.

    PubMed

    Blomkvist, A W; Andersen, S; de Bruin, E D; Jorgensen, M G

    2016-02-03

    Low hand grip strength is a strong predictor for both long-term and short-term disability and mortality. The Nintendo Wii Balance Board (WBB) is an inexpensive, portable, wide-spread instrument with the potential for multiple purposes in assessing clinically relevant measures including muscle strength. The purpose of the study was to explore intrarater reliability and concurrent validity of the WBB by comparing it to the Jamar hand dynamometer. Intra-rater test-retest cohort design with randomized validity testing on the first session. Using custom WBB software, thirty old adults (69.0 ± 4.2 years of age) were studied for reproducibility and concurrent validity compared to the Jamar hand dynamometer. Reproducibility was tested for dominant and non-dominant hands during the same time-of-day, one week apart. Intraclass correlation coefficient (ICC) and standard error of measurement (SEM) and limits of agreement (LOA) were calculated to describe relative and absolute reproducibility respectively. To describe concurrent validity, Pearson's product-moment correlation and ICC was calculated. Reproducibility was high with ICC values of >0.948 across all measures. Both SEM and LOA were low (0.2-0.5 kg and 2.7-4.2 kg, respectively) in both the dominant and non-dominant hand. For validity, Pearson correlations were high (0.80-0.88) and ICC values were fair to good (0.763-0.803). Reproducibility for WBB was high for relative measures and acceptable for absolute measures. In addition, concurrent validity between the Jamar hand dynamometer and the WBB was acceptable. Thus, the WBB may be a valid instrument to assess hand grip strength in older adults.

  17. Association with isokinetic ankle strength measurements and normal clinical muscle testing in sciatica patients.

    PubMed

    Ustun, N; Erol, O; Ozcakar, L; Ceceli, E; Ciner, O Akar; Yorgancioglu, Z R

    2013-01-01

    Sensitive muscle strength tests are needed to measure muscle strength in the diagnosis and management of sciatica patients. The aim of this study was to assess the isokinetic muscle strength in sciatica patients' and control subjects' ankles that exhibited normal ankle muscle strength when measured clinically. Forty-six patients with L5 and/or S1 nerve compression, and whose age, sex, weight, and height matched 36 healthy volunteers, were recruited to the study. Heel-walking, toe-walking, and manual muscle testing were used to perform ankle dorsiflexion and plantar flexion strengths in clinical examination. Patients with normal ankle dorsiflexion and plantar flexion strengths assessed by manual muscle testing and heel-and toe-walking tests were included in the study. Bilateral isokinetic (concentric/concentric) ankle plantar-flexion-dorsiflexion measurements of the patients and controls were performed within the protocol of 30°/sec (5 repetitions). Peak torque and peak torque/body weight were obtained for each ankle motion of the involved limb at 30°/s speed. L5 and/or S1 nerve compression was evident in 46 patients (76 injured limbs). Mean disease duration was two years. The plantar flexion muscle strength of the patients was found to be lower than that of the controls (p=0.036). The dorsiflexion muscle strength of the patients was found to be the same as that of the controls (p=0.211). Isokinetic testing is superior to clinical muscle testing when evaluating ankle plantar flexion torque in sciatica patients. Therefore, isokinetic muscle testing may be helpful when deciding whether to place a patient into a focused rehabilitation program.

  18. Respiratory muscle strength test: is it realistic in young children?

    PubMed Central

    Heinzmann-Filho, João Paulo; Donadio, Márcio Vinícius Fagundes

    2015-01-01

    Objective: To determine the success rate of the manovacuometry test in children between 4 and 12 years of age. Methods: Cross-sectional study involving children and adolescents from 4 to 12 years of age, enrolled in three basic education schools. All subjects had the anthropometric and respiratory muscle strength (maximum inspiratory pressure and maximum expiratory pressure) data measured. Students whose parents did not authorize participation or who did not want to undergo the test were excluded. The test was considered successful when the subject reached acceptability (no air leaks) and reproducibility (variation <10% between the two major maneuvers) criteria established by guidelines. Failure was defined when subjects did not meet the above criteria. Data were expressed as mean and standard deviation and the categorical variables in absolute and relative frequency. The comparison between proportions was performed using the chi-square test. Results: We included 196 children and adolescents, mean age of 8.4±2.5 years, 53.1% female. The success rate of the manovacuometry test in children and adolescents evaluated was 92.3%. When comparing the differences between the success rates of preschool children with those children and adolescents of school age, there was a significantly lower success rate in the pre-school (85.1%) group compared to the school group (94.6%) (p=0.032). However, no significant differences (p=0.575) were found when gender comparisons were performed. Conclusions: The manovacuometry test showed a high success rate in both preschool and school population assessed. Furthermore, the rate of success appears to be related to aging. PMID:26137867

  19. Serial Changes of Quadriceps and Hamstring Muscle Strength Following Total Knee Arthroplasty: A Meta-Analysis

    PubMed Central

    Ahn, Hyeong-Sik; Lee, Dae-Hee

    2016-01-01

    This meta-analysis was performed to analyze serial changes in thigh muscles, including quadriceps and hamstring muscles, from before to one year after total knee arthroplasty (TKA). All studies sequentially comparing isokinetic quadriceps and hamstring muscle strengths between the TKA side and the contralateral uninjured limb were included in this meta-analysis. Five studies with 7 cohorts were included in this meta-analysis. The mean differences in the strengths of quadriceps and hamstring muscles between the TKA and uninjured sides were greatest three months after surgery (26.8 N∙m, 12.8 N∙m, P<0.001), but were similar to preoperative level at six months (18.4 N∙m, 7.4 N∙m P<0.001) and were maintained for up to one year (15.9 N∙m, 4.1 N∙m P<0.001). The pooled mean differences in changes in quadriceps and hamstring strengths relative to preoperative levels were 9.2 N∙m and 4.9 N∙m, respectively, three months postoperatively (P = 0.041), but were no longer significant after six months and one year. During the year after TKA, quadriceps and hamstring muscle strengths were lowest after 3 months, recovering to preoperative level after six months, but not reaching the muscle strength on the contralateral side. Relative to preoperative levels, the difference in muscle strength between the TKA and contralateral knees was only significant at three months. Because decrease of strength of the quadriceps was significantly greater than decrease in hamstring muscle strength at postoperative three months, early rehabilitation after TKA should focus on recovery of quadriceps muscle strength. PMID:26849808

  20. Effects of a Strength Training Session After an Exercise Inducing Muscle Damage on Recovery Kinetics.

    PubMed

    Abaïdia, Abd-Elbasset; Delecroix, Barthélémy; Leduc, Cédric; Lamblin, Julien; McCall, Alan; Baquet, Georges; Dupont, Grégory

    2017-01-01

    Abaïdia, A-E, Delecroix, B, Leduc, C, Lamblin, J, McCall, A, Baquet, G, and Dupont, G. Effects of a strength training session after an exercise inducing muscle damage on recovery kinetics. J Strength Cond Res 31(1): 115-125, 2017-The purpose of this study was to investigate the effects of an upper-limb strength training session the day after an exercise inducing muscle damage on recovery of performance. In a randomized crossover design, subjects performed the day after the exercise, on 2 separate occasions (passive vs. active recovery conditions) a single-leg exercise (dominant in one condition and nondominant in the other condition) consisting of 5 sets of 15 eccentric contractions of the knee flexors. Active recovery consisted of performing an upper-body strength training session the day after the exercise. Creatine kinase, hamstring strength, and muscle soreness were assessed immediately and 20, 24, and 48 hours after exercise-induced muscle damage. The upper-body strength session, after muscle-damaging exercise accelerated the recovery of slow concentric force (effect size = 0.65; 90% confidence interval = -0.06 to 1.32), but did not affect the recovery kinetics for the other outcomes. The addition of an upper-body strength training session the day after muscle-damaging activity does not negatively affect the recovery kinetics. Upper-body strength training may be programmed the day after a competition.

  1. Anabolic and Catabolic Biomarkers As Predictors of Muscle Strength Decline: The InCHIANTI Study

    PubMed Central

    Maggio, Marcello; Lauretani, Fulvio; Bandinelli, Stefania; Ceda, Gian Paolo; Di Iorio, Angelo; Giallauria, Francesco; Guralnik, Jack M.; Ferrucci, Luigi

    2010-01-01

    Abstract Background Poor muscle strength is a major public health concern in older persons, predisposing to functional limitations, increased fall risk, and higher mortality. Understanding risk factors for muscle strength decline may offer opportunities for prevention and treatment. One of the possible causes of muscle strength decline is imbalance between catabolic and anabolic signaling. This study aims to examine whether high levels of multiple catabolic and low levels of multiple anabolic biomarkers predict accelerated decline of muscle strength. Methods In a representative sample of 716 men and women aged ≥65 years in the InCHIANTI study we measured C-reactive protein, interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1RA), tumor necrosis factor-α receptor 1 as well as dehydroepiandrosterone sulfate (DHEA-S), insulin-like growth factor-1, and bioavailable testosterone. Biomarker values were divided into tertiles and the numbers of catabolic/anabolic biomarkers in the highest/lowest tertile were calculated. Hand-grip strength was measured at baseline and 3- and 6-year follow up. Results In adjusted linear mixed models, higher concentration of IL-6 (p = 0.02) and IL-1RA (p = 0.04) as well as lower levels of DHEA-S (p = 0.01) predicted muscle strength decline. After combining all inflammatory markers, the rate of decline in grip strength was progressively greater with the increasing number of dysregulated catabolic biomarkers (p = 0.01). No effect on accelerated muscle strength decline was seen according to number of dysregulated anabolic hormones. Conclusions Having multiple elevated catabolic biomarkers is a better predictor of muscle strength decline than a single biomarker alone, suggesting that a catabolic dysregulation is at the core of the mechanism leading to muscle strength decline with aging. PMID:20230273

  2. Anabolic and catabolic biomarkers as predictors of muscle strength decline: the InCHIANTI study.

    PubMed

    Stenholm, Sari; Maggio, Marcello; Lauretani, Fulvio; Bandinelli, Stefania; Ceda, Gian Paolo; Di Iorio, Angelo; Giallauria, Francesco; Guralnik, Jack M; Ferrucci, Luigi

    2010-02-01

    Poor muscle strength is a major public health concern in older persons, predisposing to functional limitations, increased fall risk, and higher mortality. Understanding risk factors for muscle strength decline may offer opportunities for prevention and treatment. One of the possible causes of muscle strength decline is imbalance between catabolic and anabolic signaling. This study aims to examine whether high levels of multiple catabolic and low levels of multiple anabolic biomarkers predict accelerated decline of muscle strength. In a representative sample of 716 men and women aged >or=65 years in the InCHIANTI study we measured C-reactive protein, interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1RA), tumor necrosis factor-alpha receptor 1 as well as dehydroepiandrosterone sulfate (DHEA-S), insulin-like growth factor-1, and bioavailable testosterone. Biomarker values were divided into tertiles and the numbers of catabolic/anabolic biomarkers in the highest/lowest tertile were calculated. Hand-grip strength was measured at baseline and 3- and 6-year follow up. In adjusted linear mixed models, higher concentration of IL-6 (p = 0.02) and IL-1RA (p = 0.04) as well as lower levels of DHEA-S (p = 0.01) predicted muscle strength decline. After combining all inflammatory markers, the rate of decline in grip strength was progressively greater with the increasing number of dysregulated catabolic biomarkers (p = 0.01). No effect on accelerated muscle strength decline was seen according to number of dysregulated anabolic hormones. Having multiple elevated catabolic biomarkers is a better predictor of muscle strength decline than a single biomarker alone, suggesting that a catabolic dysregulation is at the core of the mechanism leading to muscle strength decline with aging.

  3. Relationships between Lower Limb Muscle Strength and Locomotor Capacity in Children and Adolescents with Cerebral Palsy Who Walk Independently

    ERIC Educational Resources Information Center

    Ferland, Chantale; Lepage, Celine; Moffet, Helene; Maltais, Desiree B.

    2012-01-01

    This study aimed to quantify relationships between lower limb muscle strength and locomotor capacity for children and adolescents with cerebral palsy (CP) to identify key muscle groups for strength training. Fifty 6- to 16-year-olds with CP (Gross Motor Function Classification System level I or II) participated. Isometric muscle strength of hip…

  4. Evaluation of Relationship between Trunk Muscle Endurance and Static Balance in Male Students

    PubMed Central

    Barati, Amirhossein; SafarCherati, Afsaneh; Aghayari, Azar; Azizi, Faeze; Abbasi, Hamed

    2013-01-01

    Purpose Fatigue of trunk muscle contributes to spinal instability over strenuous and prolonged physical tasks and therefore may lead to injury, however from a performance perspective, relation between endurance efficient core muscles and optimal balance control has not been well-known. The purpose of this study was to examine the relationship of trunk muscle endurance and static balance. Methods Fifty male students inhabitant of Tehran university dormitory (age 23.9±2.4, height 173.0±4.5 weight 70.7±6.3) took part in the study. Trunk muscle endurance was assessed using Sørensen test of trunk extensor endurance, trunk flexor endurance test, side bridge endurance test and static balance was measured using single-limb stance test. A multiple linear regression analysis was applied to test if the trunk muscle endurance measures significantly predicted the static balance. Results There were positive correlations between static balance level and trunk flexor, extensor and lateral endurance measures (Pearson correlation test, r=0.80 and P<0.001; r=0.71 and P<0.001; r=0.84 and P<0.001, respectively). According to multiple regression analysis for variables predicting static balance, the linear combination of trunk muscle endurance measures was significantly related to the static balance (F (3,46) = 66.60, P<0.001). Endurance of trunk flexor, extensor and lateral muscles were significantly associated with the static balance level. The regression model which included these factors had the sample multiple correlation coefficient of 0.902, indicating that approximately 81% of the variance of the static balance is explained by the model. Conclusion There is a significant relationship between trunk muscle endurance and static balance. PMID:24800004

  5. Relation between systemic inflammatory markers, peripheral muscle mass, and strength in limb muscles in stable COPD patients.

    PubMed

    Ferrari, Renata; Caram, Laura M O; Faganello, Marcia M; Sanchez, Fernanda F; Tanni, Suzana E; Godoy, Irma

    2015-01-01

    The aim of this study was to investigate the association between systemic inflammatory mediators and peripheral muscle mass and strength in COPD patients. Fifty-five patients (69% male; age: 64±9 years) with mild/very severe COPD (defined as forced expiratory volume in the first second [FEV1] =54%±23%) were evaluated. We evaluated serum concentrations of IL-8, CRP, and TNF-α. Peripheral muscle mass was evaluated by computerized tomography (CT); midthigh cross-sectional muscle area (MTCSA) and midarm cross-sectional muscle area (MACSA) were obtained. Quadriceps, triceps, and biceps strength were assessed through the determination of the one-repetition maximum. The multiple regression results, adjusted for age, sex, and FEV1%, showed positive significant association between MTCSA and leg extension (0.35 [0.16, 0.55]; P=0.001), between MACSA and triceps pulley (0.45 [0.31, 0.58]; P=0.001), and between MACSA and biceps curl (0.34 [0.22, 0.47]; P=0.001). Plasma TNF-α was negatively associated with leg extension (-3.09 [-5.99, -0.18]; P=0.04) and triceps pulley (-1.31 [-2.35, -0.28]; P=0.01), while plasma CRP presented negative association with biceps curl (-0.06 [-0.11, -0.01]; P=0.02). Our results showed negative association between peripheral muscle mass (evaluated by CT) and muscle strength and that systemic inflammation has a negative influence in the strength of specific groups of muscles in individuals with stable COPD. This is the first study showing association between systemic inflammatory markers and strength in upper limb muscles.

  6. Subclinical Hypothyroidism has Little Influences on Muscle Mass or Strength in Elderly People

    PubMed Central

    Moon, Min Kyong; Lee, You Jin; Choi, Sung Hee; Lim, Soo; Yang, Eun Joo; Lim, Jae-Young; Paik, Nam-Jong; Kim, Ki Woong; Park, Kyong Soo; Jang, Hak C.

    2010-01-01

    Sarcopenia, the age-related decline in muscle mass, affects the muscle strength and muscle quality, and these changes decrease functional capacity. The prevalence of thyroid dysfunction increases with age, and changes in thyroid hormone level lead to neuromuscular deficits. We investigated the effects of subclinical hypothyroidism on the muscle mass, strength or quality in elderly people. One thousand one hundred eighteen subjects aged ≥65 yr were randomly selected from a local population and classified into a euthyroid (280 men and 358 women), subclinically hypothyroid (61 men and 75 women), or overtly hypothyroid (7 men and 16 women) group. Although women with subclinical hypothyroidism had a higher prevalence of sarcopenia, defined according to the ratio of appendicular skeletal muscle mass to the square of height, muscle mass, strength or quality did not differ in relation to thyroid status in men or in women. Multivariate analysis including age, diabetes, hypertension, acute coronary event, alcohol, smoking, presence of pain, physical activity score, and lipid profile, showed that thyroid-stimulating hormone level was not associated with muscle mass, strength or quality. In conclusion, subclinical hypothyroidism has little influences on muscle mass, strength or quality, and may not be associated with sarcopenia. PMID:20676329

  7. Subclinical hypothyroidism has little influences on muscle mass or strength in elderly people.

    PubMed

    Moon, Min Kyong; Lee, You Jin; Choi, Sung Hee; Lim, Soo; Yang, Eun Joo; Lim, Jae-Young; Paik, Nam-Jong; Kim, Ki Woong; Park, Kyong Soo; Jang, Hak C; Cho, Bo Youn; Park, Young Joo

    2010-08-01

    Sarcopenia, the age-related decline in muscle mass, affects the muscle strength and muscle quality, and these changes decrease functional capacity. The prevalence of thyroid dysfunction increases with age, and changes in thyroid hormone level lead to neuromuscular deficits. We investigated the effects of subclinical hypothyroidism on the muscle mass, strength or quality in elderly people. One thousand one hundred eighteen subjects aged > or = 65 yr were randomly selected from a local population and classified into a euthyroid (280 men and 358 women), subclinically hypothyroid (61 men and 75 women), or overtly hypothyroid (7 men and 16 women) group. Although women with subclinical hypothyroidism had a higher prevalence of sarcopenia, defined according to the ratio of appendicular skeletal muscle mass to the square of height, muscle mass, strength or quality did not differ in relation to thyroid status in men or in women. Multivariate analysis including age, diabetes, hypertension, acute coronary event, alcohol, smoking, presence of pain, physical activity score, and lipid profile, showed that thyroid-stimulating hormone level was not associated with muscle mass, strength or quality. In conclusion, subclinical hypothyroidism has little influences on muscle mass, strength or quality, and may not be associated with sarcopenia.

  8. Sarcopenia during neoadjuvant therapy for oesophageal cancer: characterising the impact on muscle strength and physical performance.

    PubMed

    Guinan, Emer M; Doyle, S L; Bennett, A E; O'Neill, L; Gannon, J; Elliott, J A; O'Sullivan, J; Reynolds, J V; Hussey, J

    2018-05-01

    Preoperative chemo(radio)therapy for oesophageal cancer (OC) may have an attritional impact on body composition and functional status, impacting postoperative outcome. Physical decline with skeletal muscle loss has not been previously characterised in OC and may be amenable to physical rehabilitation. This study characterises skeletal muscle mass and physical performance from diagnosis to post-neoadjuvant therapy in patients undergoing preoperative chemo(radio)therapy for OC. Measures of body composition (axial computerised tomography), muscle strength (handgrip), functional capacity (walking distance), anthropometry (weight, height and waist circumference), physical activity, quality-of-life and nutritional status were captured prospectively. Sarcopenia status was defined as pre-sarcopenic (low muscle mass only), sarcopenic (low muscle mass and low muscle strength or function) or severely sarcopenic (low muscle mass and low muscle strength and low muscle function). Twenty-eight participants were studied at both time points (mean age 62.86 ± 8.18 years, n = 23 male). Lean body mass reduced by 4.9 (95% confidence interval 3.2 to 6.7) kg and mean grip strength reduced by 4.3 (2.5 to 6.1) kg from pre- to post-neoadjuvant therapy. Quality-of-life scores capturing gastrointestinal symptoms improved. Measures of anthropometry, walking distance, physical activity and nutritional status did not change. There was an increase in sarcopenic status from diagnosis (pre-sarcopenic n = 2) to post-treatment (pre-sarcopenic n = 5, severely sarcopenic n = 1). Despite maintenance of body weight, functional capacity and activity habits, participants experience declines in muscle mass and strength. Interventions involving exercise and/or nutritional support to build muscle mass and strength during preoperative therapy, even in patients who are functioning normally, are warranted.

  9. Effects of bioDensity Training and Power Plate Whole-Body Vibration on Strength, Balance, and Functional Independence in Older Adults.

    PubMed

    Smith, Derek T; Judge, Stacey; Malone, Ashley; Moynes, Rebecca C; Conviser, Jason; Skinner, James S

    2016-01-01

    Reduced strength, balance, and functional independence diminish quality of life and increase health care costs. Sixty adults (82.2 ± 4.9 years) were randomized to a control or three 12-week intervention groups: bioDensity (bD); Power Plate (PP) whole-body vibration (WBV); or bD+PP. bD involved one weekly 5-s maximal contraction of four muscle groups. PP involved two 5-min WBV sessions. Primary outcomes were strength, balance, and Functional Independence Measure (FIM). No groups differed initially. Strength significantly increased 22-51% for three muscle groups in bD and bD+PP (P < .001), with no changes in control and PP. Balance significantly improved in PP and bD+PP but not in control or bD. bD, PP, and bD+PP differentially improved FIM self-care and mobility. Strength improvements from weekly 5-min sessions of bD may impart health/clinical benefits. Balance and leg strength improvements suggest WBV beneficially impacts fall risk and incidence. Improved FIM scores are encouraging and justify larger controlled trials on bD and bD+PP efficacy.

  10. THIGH MUSCLE CROSS-SECTIONAL AREAS AND STRENGTH IN KNEES WITH EARLY VS KNEES WITHOUT RADIOGRAPHIC KNEE OSTEOARTHRITIS: A BETWEEN-KNEE, WITHIN-PERSON COMPARISON

    PubMed Central

    Ruhdorfer, AS; Dannhauer, T; Wirth, W; Cotofana, S; Roemer, F; Nevitt, M; Eckstein, F

    2014-01-01

    Objective To compare cross-sectional and longitudinal side-differences in thigh muscle anatomical cross-sectional areas (ACSAs), muscle strength, and specific strength (strength/ACSA), between knees with early radiographic change vs. knees without radiographic knee osteoarthritis (RKOA), in the same person. Design 55 (of 4796) Osteoarthritis Initiative participants fulfilled the inclusion criteria of early RKOA in one limb (definite tibiofemoral osteophytes; no radiographic joint space narrowing [JSN]) vs. no RKOA (no osteophyte; no JSN) in the contralateral limb. ACSAs of the thigh muscles and quadriceps heads were determined using axial MRIs at 33%/30% femoral length (distal to proximal). Isometric extensor and flexor muscle strength were measured (Good Strength Chair). Baseline quadriceps ACSA and extensor (specific) strength represented the primary analytic focus, and two-year changes of quadriceps ACSAs the secondary focus. Results No statistically significant side-differences in quadriceps (or other thigh muscle) ACSAs, muscle strength, or specific strength were observed between early RKOA vs. contralateral limbs without RKOA (p≥0.44), neither in men nor in women. The two-year reduction in quadriceps ACSA in limbs with early RKOA was −0.9±6% (mean ± standard deviation) vs. −0.5±6% in limbs without RKOA (statistical difference p=0.85). Conclusion Our results do not provide evidence that early unilateral radiographic changes, i.e. presence of osteophytes, are associated with cross-sectional or longitudinal differences in quadriceps muscle status compared with contralateral knees without RKOA. At the stage of early unilateral RKOA there thus appears to be no clinical need for countervailing a potential dys-balance in quadriceps ACSAs and strength between both knees. PMID:25278072

  11. Changes in muscle strength in individuals with statin-induced myopathy: A summary of 3 investigations.

    PubMed

    Panza, Gregory A; Taylor, Beth A; Dada, Marcin R; Thompson, Paul D

    2015-01-01

    There are inconsistent findings regarding muscular weakness in individuals with statin-induced myalgia. We used rigorous muscle testing to compare findings from 3 investigations in 3 different study populations to determine if statin myalgia is associated with measurable weakness. In all 3 studies, we measured maximal isometric handgrip strength, resting respiratory exchange ratio (RER), and knee extensor isometric and isokinetic force. In 2 of the 3 studies, elbow flexor isometric and isokinetic force and knee endurance fatigue index were also assessed. Knee extensor and elbow flexor measurements were obtained using an isokinetic dynamometer. Resting RER was measured using a metabolic breath-by-breath collection method. Measurement outcomes were compared on vs off drug. In study 1, 18 participants fit the criteria for statin myalgia. Participants taking atorvastatin 80 mg daily had significantly lower muscle strength in 5 (P < .05) of 14 measured variables. Participants on placebo (N = 10) with myalgia had significantly lower muscle strength in 4 (P < .05) of 14 measured variables. In study 2, 18 participants tested positive for statin-induced myalgia when receiving simvastatin 20 mg daily and displayed no significant muscle strength changes (all P > .05). In study 3, 11 patients with statin-induced myalgia completed the study and had a significant decrease in 2 (P < .05) of 10 leg muscle strength variables. In all 3 studies, no significant changes were shown for handgrip strength or RER (all P > .05). Our results indicate that after a short-term treatment with statin therapy, a rigorous muscle strength protocol does not show decrements of muscle strength in subjects with statin myalgia. Short-term treatment with statin therapy is not common in clinical practice. Thus, future studies should examine the effects of prolonged statin therapy on muscle strength. Published by Elsevier Inc.

  12. Strength Training Using Elastic Bands: Improvement of Muscle Power and Throwing Performance in Young Female Handball Players.

    PubMed

    Mascarin, Naryana Cristina; de Lira, Claudio Andre Barbosa; Vancini, Rodrigo Luiz; de Castro Pochini, Alberto; da Silva, Antonio Carlos; Dos Santos Andrade, Marilia

    2017-05-01

    Imbalance in shoulder-rotator muscles has been considered a risk factor for injuries in handball. Strength training programs (STPs) may play an important preventive role. To verify the effects of an STP using elastic bands on shoulder muscles and ball-throwing speed. Randomized and prospective controlled trial. Exercise physiology laboratory. Thirty-nine female handball players were randomly assigned to an experimental (EG, n = 21, 15.3 ± 1.1 y) or a control (CG, n = 18, 15.0 ± 0.8 y) group. The EG performed the STP with elastic-band progressive exercises for 6 wk before regular handball training, and the CG underwent only their regular training. Before and after the STP, both groups underwent a ball-throwing-speed test and isokinetic test to assess shoulder internal- (IR) and external-rotator muscle performance. Average power values for IR muscles presented a significant group-vs-time interaction effect (F = 3.9, P = .05); EG presented significantly higher values after the STP (P = .03). Ball speed presented higher values in EG after the STP in standing (P = .04) and jumping (P = .03) throws. IR peak-torque values and balance in shoulder-rotator muscles presented no group-vs-time interaction effect. STP using elastic bands performed for 6 wk was effective to improve muscle power and ball speed for young female handball players.

  13. [Association of muscle strength with early markers of cardiovascular risk in sedentary adults].

    PubMed

    Triana-Reina, Héctor Reynaldo; Ramírez-Vélez, Robinson

    2013-10-01

    To assess the association between muscle strength and early cardiovascular risk (CVR) markers in sedentary adults. A total of 176 sedentary subjects aged 18-30 years were enrolled. Body mass index and fat percentage were calculated, and waist circumference, grip strength by dynamometry, systolic blood pressure, diastolic blood pressure, mean arterial pressure, and maximal oxygen uptake by VO2max were measured as CVR markers. A multivariate logistic regression analysis was used to assess associations between muscle strength and CVR markers. Inverse correlations were found between muscle strength and adiposity (r=-.317; P=.001), waist circumference (r=-.309; P=.001), systolic blood pressure (r=-.401; P=.001), and mean arterial pressure (r=-.256; P=.001). Subjects with lower levels of muscle strength had a 5.79-fold (95% CI 1.57 to 9.34; P=.008) risk of having higher adiposity levels (≥25%) and a 9.67-fold (95% CI=3.86 to 19.22; P<.001) risk of having lower physical capacity values for VO2max (≤31.5mL/kg/min(-1)). In sedentary adults, muscle strength is associated to early manifestations of CVR. It is suggested that muscle strength testing is added to routine measurement of VO2max and traditional risk factors for prevention and treatment of cardiovascular risk. Copyright © 2012 SEEN. Published by Elsevier Espana. All rights reserved.

  14. Muscle atrophy in cachexia: can dietary protein tip the balance?

    PubMed

    Op den Kamp, Céline M; Langen, Ramon C; Haegens, Astrid; Schols, Annemie M

    2009-11-01

    To review the efficacy of dietary protein supplementation in attenuating muscle atrophy in cachexia. Only very few recent randomized controlled trials have studied the effects of protein supplementation in clinical cachexia. It appears that supplementation of dietary protein (>1.5 g/kg per day) alone or in combination with other anabolic stimuli such as exercise training maintains or even improves muscle mass, but results on muscle function are controversial and no clinical studies have yet directly linked alterations in cellular signaling or metabolic signatures of protein intake-induced muscle anabolism to muscle weight gain. To elucidate the role of dietary protein supplementation in attenuating muscle atrophy in cachectic patients, randomized clinical trials are needed in adequately phenotyped patients using sensitive measures of muscle mass and function.

  15. The effect of bridge exercise method on the strength of rectus abdominis muscle and the muscle activity of paraspinal muscles while doing treadmill walking with high heels.

    PubMed

    Kang, Taewook; Lee, Jaeseok; Seo, Junghoon; Han, Dongwook

    2017-04-01

    [Purpose] The purpose of this research is to investigate the effect of the method of bridge exercise on the change of rectus abdominis muscle and the muscle activity of paraspinal muscles while doing treadmill walking with high heels. [Subjects and Methods] The subjects of this research are healthy female students consisting of 10 persons performing bridge exercises in a supine group, 10 persons performing bridge exercises in a prone group, and 10 persons in a control group while in S university in Busan. Bridge exercise in supine position is performed in hook lying position. Bridge exercise in prone position is plank exercise in prostrate position. To measure the strength of rectus abdominis muscle, maintaining times of the posture was used. To measure the muscle activity of paraspinal muscles, EMG (4D-MT & EMD-11, Relive, Korea) was used. [Results] The strength of rectus abdominis muscle of both bridge exercises in the supine group and bridge exercises in the prone group increases significantly after exercise. The muscle activity of paraspinal muscle such as thoracic parts and lumbar parts in bridge exercises in the prone group decreases statistically while walking on a treadmill with high heels. Muscle activity of thoracic parts paraspinal muscle and bridge exercises in the supine group decreased significantly. [Conclusion] According to this study, we noticed that bridge exercise in a prone position is desirable for women who prefer wearing high heels as a back pain prevention exercise method.

  16. The effects of strength and power training on single-step balance recovery in older adults: a preliminary study.

    PubMed

    Pamukoff, Derek N; Haakonssen, Eric C; Zaccaria, Joseph A; Madigan, Michael L; Miller, Michael E; Marsh, Anthony P

    2014-01-01

    Improving muscle strength and power may mitigate the effects of sarcopenia, but it is unknown if this improves an older adult's ability to recover from a large postural perturbation. Forward tripping is prevalent in older adults and lateral falls are important due to risk of hip fracture. We used a forward and a lateral single-step balance recovery task to examine the effects of strength training (ST) or power (PT) training on single-step balance recovery in older adults. Twenty older adults (70.8±4.4 years, eleven male) were randomly assigned to either a 6-week (three times/week) lower extremity ST or PT intervention. Maximum forward (FLean(max)) and lateral (LLean(max)) lean angle and strength and power in knee extension and leg press were assessed at baseline and follow-up. Fifteen participants completed the study (ST =7, PT =8). Least squares means (95% CI) for ΔFLean(max) (ST: +4.1° [0.7, 7.5]; PT: +0.6° [-2.5, 3.8]) and ΔLLean(max) (ST: +2.2° [0.4, 4.1]; PT: +2.6° [0.9, 4.4]) indicated no differences between groups following training. In exploratory post hoc analyses collapsed by group, ΔFLean(max) was +2.4° (0.1, 4.7) and ΔLLean(max) was +2.4° (1.2, 3.6). These improvements on the balance recovery tasks ranged from ~15%-30%. The results of this preliminary study suggest that resistance training may improve balance recovery performance, and that, in this small sample, PT did not lead to larger improvements in single-step balance recovery compared to ST.

  17. Associations of knee extensor strength and standing balance with physical function in knee osteoarthritis.

    PubMed

    Pua, Yong-Hao; Liang, Zhiqi; Ong, Peck-Hoon; Bryant, Adam L; Lo, Ngai-Nung; Clark, Ross A

    2011-12-01

    Knee extensor strength is an important correlate of physical function in patients with knee osteoarthritis; however, it remains unclear whether standing balance is also a correlate. The purpose of this study was to evaluate the cross-sectional associations of knee extensor strength, standing balance, and their interaction with physical function. One hundred four older adults with end-stage knee osteoarthritis awaiting a total knee replacement (mean ± SD age 67 ± 8 years) participated. Isometric knee extensor strength was measured using an isokinetic dynamometer. Standing balance performance was measured by the center of pressure displacement during quiet standing on a balance board. Physical function was measured by the self-report Short Form 36 (SF-36) questionnaire and by the 10-meter fast-pace gait speed test. After adjustment for demographic and knee pain variables, we detected significant knee strength by standing balance interaction terms for both SF-36 physical function and fast-pace gait speed. Interrogation of the interaction revealed that standing balance in the anteroposterior plane was positively related to physical function among patients with lower knee extensor strength. Conversely, among patients with higher knee extensor strength, the standing balance-physical function associations were, or tended to be, negative. These findings suggest that although standing balance was related to physical function in patients with knee osteoarthritis, this relationship was complex and dependent on knee extensor strength level. These results are of importance in developing intervention strategies and refining theoretical models, but they call for further study. Copyright © 2011 by the American College of Rheumatology.

  18. The relationships of eccentric strength and power with dynamic balance in male footballers.

    PubMed

    Booysen, Marc Jon; Gradidge, Philippe Jean-Luc; Watson, Estelle

    2015-01-01

    Unilateral balance is critical to kicking accuracy in football. In order to design interventions to improve dynamic balance, knowledge of the relationships between dynamic balance and specific neuromuscular factors such as eccentric strength and power is essential. Therefore, the aim was to determine the relationships of eccentric strength and power with dynamic balance in male footballers. The Y-balance test, eccentric isokinetic strength testing (knee extensors and flexors) and the countermovement jump were assessed in fifty male footballers (university (n = 27, mean age = 20.7 ± 1.84 years) and professional (n = 23, mean age = 23.0 ± 3.08 years). Spearman Rank Order correlations were used to determine the relationships of eccentric strength and power with dynamic balance. Multiple linear regression, adjusting for age, mass, stature, playing experience and competitive level was performed on significant relationships. Normalised reach score in the Y-balance test using the non-dominant leg for stance correlated with (1) eccentric strength of the non-dominant leg knee extensors in the university group (r = 0.50, P = 0.008) and (2) countermovement jump height in the university (r = 0.40, P = 0.04) and professional (r = 0.56, P = 0.006) football groups, respectively. No relationships were observed between eccentric strength (knee flexors) and normalised reach scores. Despite the addition of potential confounders, the relationship of power and dynamic balance was significant (r = 0.52, P < 0.0002). The ability to generate power correlates moderately with dynamic balance on the non-dominant leg in male footballers.

  19. Effect of neck muscle strength and anticipatory cervical muscle activation on the kinematic response of the head to impulsive loads.

    PubMed

    Eckner, James T; Oh, Youkeun K; Joshi, Monica S; Richardson, James K; Ashton-Miller, James A

    2014-03-01

    Greater neck strength and activating the neck muscles to brace for impact are both thought to reduce an athlete's risk of concussion during a collision by attenuating the head's kinematic response after impact. However, the literature reporting the neck's role in controlling postimpact head kinematics is mixed. Furthermore, these relationships have not been examined in the coronal or transverse planes or in pediatric athletes. In each anatomic plane, peak linear velocity (ΔV) and peak angular velocity (Δω) of the head are inversely related to maximal isometric cervical muscle strength in the opposing direction (H1). Under impulsive loading, ΔV and Δω will be decreased during anticipatory cervical muscle activation compared with the baseline state (H2). Descriptive laboratory study. Maximum isometric neck strength was measured in each anatomic plane in 46 male and female contact sport athletes aged 8 to 30 years. A loading apparatus applied impulsive test forces to athletes' heads in flexion, extension, lateral flexion, and axial rotation during baseline and anticipatory cervical muscle activation conditions. Multivariate linear mixed models were used to determine the effects of neck strength and cervical muscle activation on head ΔV and Δω. Greater isometric neck strength and anticipatory activation were independently associated with decreased head ΔV and Δω after impulsive loading across all planes of motion (all P < .001). Inverse relationships between neck strength and head ΔV and Δω presented moderately strong effect sizes (r = 0.417 to r = 0.657), varying by direction of motion and cervical muscle activation. In male and female athletes across the age spectrum, greater neck strength and anticipatory cervical muscle activation ("bracing for impact") can reduce the magnitude of the head's kinematic response. Future studies should determine whether neck strength contributes to the observed sex and age group differences in concussion incidence. Neck

  20. Identification of human skeletal muscle miRNA related to strength by high-throughput sequencing.

    PubMed

    Mitchell, Cameron J; D'Souza, Randall F; Schierding, William; Zeng, Nina; Ramzan, Farha; O'Sullivan, Justin M; Poppitt, Sally D; Cameron-Smith, David

    2018-06-01

    The loss of muscle size, strength, and quality with aging is a major determinant of morbidity and mortality in the elderly. The regulatory pathways that impact the muscle phenotype include the translational regulation maintained by microRNAs (miRNA). Yet the miRNAs that are expressed in human skeletal muscle and relationship to muscle size, strength, and quality are unknown. Using next-generation sequencing, we selected the 50 most abundantly expressed miRNAs and then analyzed them in vastus lateralis muscle, obtained by biopsy from middle-aged males ( n = 48; 50.0 ± 4.3 yr). Isokinetic strength testing and midthigh computed tomography was undertaken for muscle phenotype analysis. Muscle attenuation was measured by computerized tomography and is inversely proportional to myofiber lipid content. miR-486-5p accounted for 21% of total miR sequence reads, with miR-10b-5p, miR-133a-3p, and miR-22-3p accounting for a further 15, 12, and 10%, respectively. Isokinetic knee extension strength and muscle cross-sectional area were positively correlated with miR-100-5p, miR-99b-5p, and miR-191-5p expression. Muscle attenuation was negatively correlated to let-7f-5p, miR-30d-5p, and miR-125b-5p expression. In silico analysis implicates miRNAs related to strength and muscle size in the regulation of mammalian target of rapamycin, while miRNAs related to muscle attenuation may have potential roles regulating the transforming growth factor-β/SMAD3 pathway.

  1. Cancer-Specific Mortality Relative to Engagement in Muscle-Strengthening Activities and Lower Extremity Strength.

    PubMed

    Dankel, Scott J; Loenneke, Jeremy P; Loprinzi, Paul D

    2018-02-01

    Skeletal muscle strength and engagement in muscle-strengthening activities are each inversely associated with all-cause mortality; however, less is known on their relationship with cancer-specific mortality. Data from the 1999-2002 National Health and Nutrition Examination Survey were used assessing 2773 individuals aged 50 years or older. Individuals being dichotomized at the 75th percentile for knee extensor strength, and engagement in muscle-strengthening activities was acquired through self-report with ≥2 sessions per week were classified as meeting guidelines. With respect to cancer-specific mortality, individuals in the upper quartile for muscle strength were at a 50% reduced risk (hazard ratio = 0.50; 95% confidence interval, 0.29-0.85; P = .01) and those meeting muscle-strengthening activities were at a nonsignificant 8% reduced risk (hazard ratio = 0.92; 95% confidence interval, 0.45-1.86, P = .81) of cancer-specific mortality after adjusting for covariates. Clinicians should routinely assess lower extremity strength and promote engagement in muscle-strengthening activities aimed at increasing muscle strength.

  2. Effect of core muscle thickness and static or dynamic balance on prone bridge exercise with sling by shoulder joint angle in healthy adults.

    PubMed

    Park, Mi Hwa; Yu, Jae Ho; Hong, Ji Heon; Kim, Jin Seop; Jung, Sang Woo; Lee, Dong Yeop

    2016-03-01

    [Purpose] To date, core muscle activity detected using ultrasonography during prone bridge exercises has not been reported. Here we investigated the effects of core muscle thickness and balance on sling exercise efficacy by shoulder joint angle in healthy individuals. [Subjects and Methods] Forty-three healthy university students were enrolled in this study. Ultrasonography thickness of external oblique, internal oblique, and transversus abdominis during sling workouts was investigated. Muscle thickness was measured on ultrasonography imaging before and after the experiment. Dynamic balance was tested using a functional reaching test. Static balance was tested using a Tetrax Interactive Balance System. [Results] Different muscle thicknesses were observed during the prone bridge exercise with the shoulder flexed at 60°, 90° or 120°. Shoulder flexion at 60° and 90° in the prone bridge exercise with a sling generated the greatest thickness of most transversus abdominis muscles. Shoulder flexion at 120° in the prone bridge exercise with a sling generated the greatest thickness of most external oblique muscles. [Conclusion] The results suggest that the prone bridge exercise with shoulder joint angle is an effective method of increasing global and local muscle strength.

  3. Mouse Plantar Flexor Muscle Size and Strength After Inactivity and Training

    DTIC Science & Technology

    2010-07-01

    suspension. Keywords: eccentric contraction , microgravity , exercise . SPACEFLIGHT CAUSES atrophy and strength loss in antigravity skeletal muscles...isometric, concentric, and eccentric contractions pre- served muscle mass in the rat medial gastrocnemius ( 2 ), the use of isometric resistance exercise ...Adams GR , Haddad F , Bodell PW , Tran PD , Baldwin KM . Com- bined isometric, concentric, and eccentric resistance exercise prevents

  4. Screen time viewing behaviors and isometric trunk muscle strength in youth.

    PubMed

    Grøntved, Anders; Ried-Larsen, Mathias; Froberg, Karsten; Wedderkopp, Niels; Brage, Søren; Kristensen, Peter Lund; Andersen, Lars Bo; Møller, Niels Christian

    2013-10-01

    The objective of this study was to examine the association of screen time viewing behavior with isometric trunk muscle strength in youth. A cross-sectional study was carried out including 606 adolescents (14-16 yr old) participating in the Danish European Youth Heart Study, a population-based study with assessments conducted in either 1997/1998 or 2003/2004. Maximal voluntary contractions during isometric back extension and abdominal flexion were determined using a strain gauge dynamometer, and cardiorespiratory fitness (CRF) was obtained using a maximal cycle ergometer test. TV viewing time, computer use, and other lifestyle behaviors were obtained by self-report. Analyses of association of screen use behaviors with isometric trunk muscle strength were carried out using multivariable adjusted linear regression. The mean (SD) isometric strength was 0.87 (0.16) N·kg-1. TV viewing, computer use, and total screen time use were inversely associated with isometric trunk muscle strength in analyses adjusted for lifestyle and sociodemographic factors. After further adjustment for CRF and waist circumference, associations remained significant for computer use and total screen time, but TV viewing was only marginally associated with muscle strength after these additional adjustments (-0.05 SD (95% confidence interval, -0.11 to 0.005) difference in strength per 1 h·d-1 difference in TV viewing time, P = 0.08). Each 1 h·d-1 difference in total screen time use was associated with -0.09 SD (95% confidence interval, -0.14 to -0.04) lower isometric trunk muscle strength in the fully adjusted model (P = 0.001). There were no indications that the association of screen time use with isometric trunk muscle strength was attenuated among highly fit individuals (P = 0.91 for CRF by screen time interaction). Screen time use was inversely associated with isometric trunk muscle strength independent of CRF and other confounding factors.

  5. Evaluation of peripheral muscle strength of patients undergoing elective cardiac surgery: a longitudinal study

    PubMed Central

    Santos, Kelli Maria Souza; de Cerqueira Neto, Manoel Luiz; Carvalho, Vitor Oliveira; de Santana Filho, Valter Joviniano; da Silva Junior, Walderi Monteiro; Araújo Filho, Amaro Afrânio; Cerqueira, Telma Cristina Fontes; Cacau, Lucas de Assis Pereira

    2014-01-01

    Introduction Peripheral muscle strength has been little explored in the literature in the context of cardiac rehabilitation. Objective To evaluate the peripheral muscle strength of patients undergoing elective cardiac surgery. Methods This was a longitudinal observational study. The peripheral muscle strength was measured using isometric dynamometry lower limb (knee extensors and flexors) at three different times: preoperatively (M1), the day of discharge (M2) and hospital discharge (M3). Participants received physiotherapy pre and postoperatively during the days of hospitalization during the morning and afternoon. Results Twenty-two patients were evaluated. The values of peripheral muscle strength of knee extensors preoperative found were about 50% lower than those predicted for the healthy population. When comparing muscle strength prior (M1), with the remaining evaluation, found himself in a fall of 29% for the movement of knee extension and 25% for knee flexion in M2 and a decrease of 10% movement for knee extension and 13% for knee flexion in M3 when comparing with M1. Conclusion The values of peripheral muscle strength prior of the study patients were lower than predicted for the healthy population of the same age. After the surgical event this reduction is even more remarkable, being reestablished until the time of discharge, to values close to baseline. PMID:25372909

  6. Evaluation of peripheral muscle strength of patients undergoing elective cardiac surgery: a longitudinal study.

    PubMed

    Santos, Kelli Maria Souza; Cerqueira Neto, Manoel Luiz de; Carvalho, Vitor Oliveira; Santana Filho, Valter Joviniano de; Silva Junior, Walderi Monteiro da; Araújo Filho, Amaro Afrânio; Cerqueira, Telma Cristina Fontes; Cacau, Lucas de Assis Pereira

    2014-01-01

    Peripheral muscle strength has been little explored in the literature in the context of cardiac rehabilitation. To evaluate the peripheral muscle strength of patients undergoing elective cardiac surgery. This was a longitudinal observational study. The peripheral muscle strength was measured using isometric dynamometry lower limb (knee extensors and flexors) at three different times: preoperatively (M1), the day of discharge (M2) and hospital discharge (M3). Participants received physiotherapy pre and postoperatively during the days of hospitalization during the morning and afternoon. Twenty-two patients were evaluated. The values of peripheral muscle strength of knee extensors preoperative found were about 50% lower than those predicted for the healthy population. When comparing muscle strength prior (M1), with the remaining evaluation, found himself in a fall of 29% for the movement of knee extension and 25% for knee flexion in M2 and a decrease of 10% movement for knee extension and 13% for knee flexion in M3 when comparing with M1. The values of peripheral muscle strength prior of the study patients were lower than predicted for the healthy population of the same age. After the surgical event this reduction is even more remarkable, being reestablished until the time of discharge, to values close to baseline.

  7. Effect of Lower Limb Strength on Falls and Balance of the Elderly

    PubMed Central

    Cho, Kang Hee; Bok, Soo Kyung; Hwang, Seon Lyul

    2012-01-01

    Objective To assess the effect of lower limb strength on falls and balance in community-dwelling elderly persons by a health status questionnaire, evaluation of lower limb strength and balance. Method A total of 86 subjects (age 69.8±5.3) were categorized into one of two groups, "Fallers" and "Non-fallers". Thirty one participants who had reported the experience of having fallen unexpectedly at least once in the past year were assigned into the group "Fallers", and the remaining 55 subjects having no fall history in the past year, "Non-fallers". A self-assessment questionnaire was taken. Lower limb strength was measured by a "Chair stand test". Balance was measured by the stability index of the fall risk test protocol of Balance System SD® (Biodex, New York, USA). The differences between the two groups were compared and the correlation between lower limb strength and balance were analyzed. Results The questionnaire demonstrated no significant differences between two groups. The "Chair stand test" showed a significantly less for the "Fallers" (p<0.05). The stability index was significantly greater in the "Fallers" group (p<0.05). There was a moderate negative correlation between the "Chair stand test" and the "Stability index" (R=-0.576, p<0.01). Conclusion This study suggests that the "Chair stand test" is a useful screening process for lower limb strength which correlates to risk for falls and balance in the elderly. PMID:22837975

  8. Two pilot studies of the effect of bicycling on balance and leg strength among older adults.

    PubMed

    Rissel, Chris; Passmore, Erin; Mason, Chloe; Merom, Dafna

    2013-01-01

    Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Study 1: a cross-sectional survey of 43 adults aged 44-79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT) test (decision time and response time), leg strength and timed single leg standing. Study 2: 18 older adults aged 49-72 were recruited into a 12-week cycling program. The same pre- and postmeasures as used in Study 1 were collected. Study 1: participants who had cycled in the last month performed significantly better on measures of decision time and response time. Study 2: cycling at least one hour a week was associated with significant improvements in balance (decision time and response time) and timed single leg standing. Cycling by healthy older adults appears promising for improving risk factors for falls.

  9. On the Origin of Muscle Synergies: Invariant Balance in the Co-activation of Agonist and Antagonist Muscle Pairs

    PubMed Central

    Hirai, Hiroaki; Miyazaki, Fumio; Naritomi, Hiroaki; Koba, Keitaro; Oku, Takanori; Uno, Kanna; Uemura, Mitsunori; Nishi, Tomoki; Kageyama, Masayuki; Krebs, Hermano Igo

    2015-01-01

    Investigation of neural representation of movement planning has attracted the attention of neuroscientists, as it may reveal the sensorimotor transformation essential to motor control. The analysis of muscle synergies based on the activity of agonist–antagonist (AA) muscle pairs may provide insight into such transformations, especially for a reference frame in the muscle space. In this study, we examined the AA concept using the following explanatory variables: the AA ratio, which is related to the equilibrium-joint angle, and the AA sum, which is associated with joint stiffness. We formulated muscle synergies as a function of AA sums, positing that muscle synergies are composite units of mechanical impedance. The AA concept can be regarded as another form of the equilibrium-point (EP) hypothesis, and it can be extended to the concept of EP-based synergies. We introduce, here, a novel tool for analyzing the neurological and motor functions underlying human movements and review some initial insights from our results about the relationships between muscle synergies, endpoint stiffness, and virtual trajectories (time series of EP). Our results suggest that (1) muscle synergies reflect an invariant balance in the co-activation of AA muscle pairs; (2) each synergy represents the basis for the radial, tangential, and null movements of the virtual trajectory in the polar coordinates centered on the specific joint at the base of the body; and (3) the alteration of muscle synergies (for example, due to spasticity or rigidity following neurological injury) results in significant distortion of endpoint stiffness and concomitant virtual trajectories. These results indicate that muscle synergies (i.e., the balance of muscle mechanical impedance) are essential for motor control. PMID:26636079

  10. On the Origin of Muscle Synergies: Invariant Balance in the Co-activation of Agonist and Antagonist Muscle Pairs.

    PubMed

    Hirai, Hiroaki; Miyazaki, Fumio; Naritomi, Hiroaki; Koba, Keitaro; Oku, Takanori; Uno, Kanna; Uemura, Mitsunori; Nishi, Tomoki; Kageyama, Masayuki; Krebs, Hermano Igo

    2015-01-01

    Investigation of neural representation of movement planning has attracted the attention of neuroscientists, as it may reveal the sensorimotor transformation essential to motor control. The analysis of muscle synergies based on the activity of agonist-antagonist (AA) muscle pairs may provide insight into such transformations, especially for a reference frame in the muscle space. In this study, we examined the AA concept using the following explanatory variables: the AA ratio, which is related to the equilibrium-joint angle, and the AA sum, which is associated with joint stiffness. We formulated muscle synergies as a function of AA sums, positing that muscle synergies are composite units of mechanical impedance. The AA concept can be regarded as another form of the equilibrium-point (EP) hypothesis, and it can be extended to the concept of EP-based synergies. We introduce, here, a novel tool for analyzing the neurological and motor functions underlying human movements and review some initial insights from our results about the relationships between muscle synergies, endpoint stiffness, and virtual trajectories (time series of EP). Our results suggest that (1) muscle synergies reflect an invariant balance in the co-activation of AA muscle pairs; (2) each synergy represents the basis for the radial, tangential, and null movements of the virtual trajectory in the polar coordinates centered on the specific joint at the base of the body; and (3) the alteration of muscle synergies (for example, due to spasticity or rigidity following neurological injury) results in significant distortion of endpoint stiffness and concomitant virtual trajectories. These results indicate that muscle synergies (i.e., the balance of muscle mechanical impedance) are essential for motor control.

  11. Muscle activation timing and balance response in chronic lower back pain patients with associated radiculopathy.

    PubMed

    Frost, Lydia R; Brown, Stephen H M

    2016-02-01

    Patients with chronic low back pain and associated radiculopathy present with neuromuscular symptoms both in their lower back and down their leg; however, investigations of muscle activation have so far been isolated to the lower back. During balance perturbations, it is necessary that lower limb muscles activate with proper timing and sequencing along with the lower back musculature to efficiently regain balance control. Patients with chronic low back pain and radiculopathy and matched controls completed a series of balance perturbations (rapid bilateral arm raise, unanticipated and anticipated sudden loading, and rapid rise to toe). Muscle activation timing and sequencing as well as kinetic response to the perturbations were analyzed. Patients had significantly delayed lower limb muscle activation in rapid arm raise trials as compared to controls. In sudden loading trials, muscle activation timing was not delayed in patients; however, some differences in posterior chain muscle activation sequencing were present. Patients demonstrated less anterior-posterior movement in unanticipated sudden loading trials, and greater medial-lateral movement in rise to toe trials. Patients with low back pain and radiculopathy demonstrated some significant differences from control participants in terms of muscle activation timing, sequencing, and overall balance control. The presence of differences between patients and controls, specifically in the lower limb, indicates that radiculopathy may play a role in altering balance control in these patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. An intergenerational approach in the promotion of balance and strength for fall prevention - a mini-review.

    PubMed

    Granacher, Urs; Muehlbauer, Thomas; Gollhofer, Albert; Kressig, Reto W; Zahner, Lukas

    2011-01-01

    The risk of sustaining a fall is particularly high in children and seniors. Deficits in postural control and muscle strength either due to maturation, secular declines or biologic aging are two important intrinsic risk factors for falls. During life span, performance in variables of static postural control follows a U-shaped curve with children and seniors showing larger postural sway than healthy adults. Measures of dynamic postural control (i.e. gait speed) as well as isometric (i.e. maximal strength) and dynamic muscle strength (i.e. muscular power) follow an inverted U-shaped curve during life span, again with children and seniors showing deficits compared to adults. There is evidence that particularly balance and resistance training are effective in counteracting these neuromuscular constraints in both children and seniors. Further, these training regimens are able to reduce the rate of sustaining injuries and falls in these age groups. An intergenerational intervention approach is suggested to enhance the effectiveness of these training programs by improving compliance and increasing motivation of children and seniors exercising together. Thus, the objectives of this mini-review are: (1) to describe the epidemiology and etiology of falls in children and seniors; (2) to discuss training programs that counteract intrinsic fall risk factors by reducing the rate of falling, and (3) to present an intergenerational approach that has the potential to make training programs even more effective by including children and seniors together in one exercise group. Copyright © 2010 S. Karger AG, Basel.

  13. Osteosarcopenic obesity is associated with reduced handgrip strength, walking abilities, and balance in postmenopausal women.

    PubMed

    Ilich, J Z; Inglis, J E; Kelly, O J; McGee, D L

    2015-11-01

    We determined the prevalence of osteosarcopenic obesity (loss of bone and muscle coexistent with increased adiposity) in overweight/obese postmenopausal women and compared their functionality to obese-only women. Results showed that osteosarcopenic obese women were outperformed by obese-only women in handgrip strength and walking/balance abilities indicating their higher risk for mobility impairments. Osteosarcopenic obesity (OSO) is a recently defined triad of osteopenia/osteoporosis, sarcopenia, and adiposity. We identified women with OSO in overweight/obese postmenopausal women and evaluated their functionality comparing them with obese-only (OB) women. Additionally, women with osteopenic/osteoporotic obesity (OO), but no sarcopenia, and those with sarcopenic obesity (SO), but no osteopenia/osteoporosis, were identified and compared. We hypothesized that OSO women will have the lowest scores for each of the functionality measures. Participants (n = 258; % body fat ≥35) were assessed using a Lunar iDXA instrument for bone and body composition. Sarcopenia was determined from negative residuals of linear regression modeled on appendicular lean mass, height, and body fat, using 20th percentile as a cutoff. Participants with T-scores of L1-L4 vertebrae and/or total femur <-1, but without sarcopenia, were identified as OO (n = 99) and those with normal T-scores, but with sarcopenia, as SO (n = 28). OSO (n = 32) included women with both osteopenia/osteoporosis and sarcopenia, while those with normal bone and no sarcopenia were classified as OB (n = 99). Functionality measures such as handgrip strength, normal/brisk walking speed, and right/left leg stance were evaluated and compared among groups. Women with OSO presented with the lowest handgrip scores, slowest normal and brisk walking speed, and shortest time for each leg stance, but these results were statistically significantly different only from the OB group. These findings indicate a poorer

  14. Lean muscle volume of the thigh has a stronger relationship with muscle power than muscle strength in women with knee osteoarthritis.

    PubMed

    Davison, Michael J; Maly, Monica R; Keir, Peter J; Hapuhennedige, Sandani M; Kron, Amie T; Adachi, Jonathan D; Beattie, Karen A

    2017-01-01

    Thigh lean muscle and intramuscular fat have been implicated in the impairment of physical function observed in people with knee osteoarthritis. We investigated the relationships of quadriceps and hamstrings intramuscular fat fraction and lean muscle volume with muscle power and strength, controlling for neuromuscular activation, and physical performance in women with knee OA. Women (n=20) 55years or older with symptomatic, radiographic knee osteoarthritis underwent a 3.0T magnetic resonance imaging scan of the thigh of their most symptomatic knee. Axial fat-separated images were analyzed using software to quantify intramuscular fat and lean muscle volumes of the quadriceps and hamstrings. To quantify strength and power of the knee extensors and flexors, participants performed maximum voluntary isometric contraction and isotonic knee extensions and flexions, respectively. Electromyography of the quadriceps and hamstrings was measured. Participants also completed five physical performance tests. Quadriceps and hamstrings lean muscle volumes were related to isotonic knee extensor (B=0.624; p=0.017) and flexor (B=1.518; p=0.032) power, but not knee extensor (B=0.001; p=0.615) or flexor (B=0.001; p=0.564) isometric strength. Intramuscular fat fractions were not related to isotonic knee extensor or flexor power, nor isometric strength. No relationships were found between intramuscular fat or lean muscle volume and physical performance. Muscle power may be more sensitive than strength to lean muscle mass in women with knee osteoarthritis. Thigh lean muscle mass, but neither intramuscular nor intermuscular fat, is related to knee extensor and flexor power in women with knee osteoarthritis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Effects of isokinetic calf muscle exercise program on muscle strength and venous function in patients with chronic venous insufficiency.

    PubMed

    Ercan, Sabriye; Çetin, Cem; Yavuz, Turhan; Demir, Hilmi M; Atalay, Yurdagül B

    2018-05-01

    Objective The aim of this study was to observe the change of the ankle joint range of motion, the muscle strength values measured with an isokinetic dynamometer, pain scores, quality of life scale, and venous return time in chronic venous insufficiency diagnosed patients by prospective follow-up after 12-week exercise program including isokinetic exercises. Methods The patient group of this study comprised 27 patients (23 female, 4 male) who were diagnosed with chronic venous insufficiency. An exercise program including isokinetic exercise for the calf muscle was given to patients three days per week for 12 weeks. At the end of 12 weeks, five of the patients left the study due to inadequate compliance with the exercise program. As a result, control data of 22 patients were included. Ankle joint range of active motion, isokinetic muscle strength, pain, quality of life, and photoplethysmography measurements were assessed before starting and after the exercise program. Results Evaluating changes of the starting and control data depending on time showed that all isokinetic muscle strength measurement parameters, range of motion, and overall quality of life values of patients improved. Venous return time values have also increased significantly ( p < 0.05). Conclusion In conclusion, increase in muscle strength has been provided with exercise therapy in patients with chronic venous insufficiency. It has been determined that the increase in muscle strength affected the venous pump and this ensured improvement in venous function and range of motion of the ankle. In addition, it has been detected that pain reduced and quality of life improved after the exercise program.

  16. Effects of Swiss-ball core strength training on strength, endurance, flexibility, and balance in sedentary women.

    PubMed

    Sekendiz, Betül; Cuğ, Mutlu; Korkusuz, Feza

    2010-11-01

    The purpose of this study was to investigate the effects of Swiss-ball core strength training on trunk extensor (abdominal)/flexor (lower back) and lower limb extensor (quadriceps)/flexor (hamstring) muscular strength, abdominal, lower back and leg endurance, flexibility and dynamic balance in sedentary women (n = 21; age = 34 ± 8.09; height = 1.63 ± 6.91 cm; weight = 64 ± 8.69 kg) trained for 45 minutes, 3 d·wk-1 for 12 weeks. Results of multivariate analysis revealed significant difference (p ≤ 0.05) between pre and postmeasures of 60 and 90° s trunk flexion/extension, 60 and 240° s-1 lower limb flexion/extension (Biodex Isokinetic Dynamometer), abdominal endurance (curl-up test), lower back muscular endurance (modified Sorensen test), lower limb endurance (repetitive squat test), lower back flexibility (sit and reach test), and dynamic balance (functional reach test). The results support the fact that Swiss-ball core strength training exercises can be used to provide improvement in the aforementioned measures in sedentary women. In conclusion, this study provides practical implications for sedentary individuals, physiotherapists, strength and conditioning specialists who can benefit from core strength training with Swiss balls.

  17. Correlation of ankle eversion to inversion strength ratio and static balance in dominant and non-dominant limbs of basketball players.

    PubMed

    Dabadghav, Rachana

    2016-04-01

    To compare ankle eversion to inversion strength ratio (E/I R) and static balance control between the dominant and non-dominant limbs of basketball players and to correlate ankle E/I R and static balance control in the dominant and non-dominant limbs of basketball players. Twenty-one healthy basketball players in the age-group of 18-25 years participated in this study. Isokinetic ankle eversion and inversion muscle strength was assessed at 30°/s and 120°/s in both dominant and non-dominant limbs using the Biodex isokinetic dynamometer. Similarly balance was assessed on a force platform with eyes open and eyes closed in both dominant and non-dominant limbs. Repeated measure ANOVA for strength measurement, found that there was significant main effect of speed, P=0.001 (P<0.05). However, there was no significant main effect in the sides P=0.099 (P<0.05).There was significant main effect of sides with respect to balance. Balance was affected more in non-dominant limb P=0.000 as compared to dominant limb. However, there was not much of a significant difference with eyes open and eyes closed position. The E/I ratio was >1.0 at the angular velocity of 120°/s increasing the chances of ankle injuries in basketball players. There was no correlation between ankle strength and balance in both dominant and non-dominant limbs.

  18. Do oarsmen have asymmetries in the strength of their back and leg muscles?

    PubMed

    Parkin, S; Nowicky, A V; Rutherford, O M; McGregor, A H

    2001-07-01

    The aim of this study was to establish whether asymmetry of the strength of the leg and trunk musculature is more prominent in rowers than in controls. Nineteen oarsmen and 20 male controls matched for age, height and body mass performed a series of isokinetic and isometric strength tests on an isokinetic dynamometer. These strength tests focused on the trunk and leg muscles. Comparisons of strength were made between and within groups for right and left symmetry patterns, hamstring: quadriceps ratios, and trunk flexor and extensor ratios. The results revealed no left and right asymmetries in either the knee extensor or flexor strength parameters (including both isometric and isokinetic measures). Knee extensor strength was significantly greater in the rowing population, but knee flexor strength was similar between the two groups. No difference was seen between the groups for the hamstring: quadriceps strength ratio. In the rowing population, stroke side had no influence on leg strength. No differences were observed in the isometric strength of the trunk flexors and extensors between groups, although EMG activity was significantly higher in the rowing population. Patterns of asymmetry of muscle activity were observed between the left and right erector spinae muscles during extension, which was significantly related to rowing side (P < 0.01). These observations could be related to the high incidence of low back pain in oarsmen.

  19. Effects of Different Environment Temperatures on Some Motor Characteristics and Muscle Strength

    ERIC Educational Resources Information Center

    Çakir, Ergün; Yüksek, Selami; Asma, Bülent; Arslanoglu, Erkal

    2016-01-01

    The aim of this study was determine the effects of different environment temperatures on motor characteristics and muscle strength. 15 athletes participated to study. Flexibility, vertical jump, hand grip-leg strength, 30m sprint, 20-meter shuttle run and coordination-agility tests were measured in five different environment temperatures. (22°C,…

  20. The relationship between hamstring length and gluteal muscle strength in individuals with sacroiliac joint dysfunction

    PubMed Central

    Massoud Arab, Amir; Reza Nourbakhsh, Mohammad; Mohammadifar, Ali

    2011-01-01

    It has been suggested that tight hamstring muscle, due to its anatomical connections, could be a compensatory mechanism for providing sacroiliac (SI) joint stability in patients with gluteal muscle weakness and SIJ dysfunction. The purpose of this study was to determine the relationship between hamstring muscle length and gluteal muscle strength in subjects with sacroiliac joint dysfunction. A total of 159 subjects with and without low back pain (LBP) between the ages of 20 and 65 years participate in the study. Subjects were categorized into three groups: LBP without SIJ involvement (n = 53); back pain with SIJ dysfunction (n = 53); and no low back pain (n = 53). Hamstring muscle length and gluteal muscle strength were measured in all subjects. The number of individuals with gluteal weakness was significantly (P = 0.02) higher in subjects with SI joint dysfunction (66%) compared to those with LBP without SI joint dysfunctions (34%). In pooled data, there was no significant difference (P = 0.31) in hamstring muscle length between subjects with SI joint dysfunction and those with back pain without SI involvement. In subjects with SI joint dysfunction, however, those with gluteal muscle weakness had significantly (P = 0.02) shorter hamstring muscle length (mean = 158±11°) compared to individuals without gluteal weakness (mean = 165±10°). There was no statistically significant difference (P>0.05) in hamstring muscle length between individuals with and without gluteal muscle weakness in other groups. In conclusion, hamstring tightness in subjects with SI joint dysfunction could be related to gluteal muscle weakness. The slight difference in hamstring muscle length found in this study, although statistically significant, was not sufficient for making any definite conclusions. Further studies are needed to establish the role of hamstring muscle in SI joint stability. PMID:22294848

  1. The relationship between hamstring length and gluteal muscle strength in individuals with sacroiliac joint dysfunction.

    PubMed

    Massoud Arab, Amir; Reza Nourbakhsh, Mohammad; Mohammadifar, Ali

    2011-02-01

    It has been suggested that tight hamstring muscle, due to its anatomical connections, could be a compensatory mechanism for providing sacroiliac (SI) joint stability in patients with gluteal muscle weakness and SIJ dysfunction. The purpose of this study was to determine the relationship between hamstring muscle length and gluteal muscle strength in subjects with sacroiliac joint dysfunction. A total of 159 subjects with and without low back pain (LBP) between the ages of 20 and 65 years participate in the study. Subjects were categorized into three groups: LBP without SIJ involvement (n = 53); back pain with SIJ dysfunction (n = 53); and no low back pain (n = 53). Hamstring muscle length and gluteal muscle strength were measured in all subjects. The number of individuals with gluteal weakness was significantly (P = 0.02) higher in subjects with SI joint dysfunction (66%) compared to those with LBP without SI joint dysfunctions (34%). In pooled data, there was no significant difference (P = 0.31) in hamstring muscle length between subjects with SI joint dysfunction and those with back pain without SI involvement. In subjects with SI joint dysfunction, however, those with gluteal muscle weakness had significantly (P = 0.02) shorter hamstring muscle length (mean = 158±11°) compared to individuals without gluteal weakness (mean = 165±10°). There was no statistically significant difference (P>0.05) in hamstring muscle length between individuals with and without gluteal muscle weakness in other groups. In conclusion, hamstring tightness in subjects with SI joint dysfunction could be related to gluteal muscle weakness. The slight difference in hamstring muscle length found in this study, although statistically significant, was not sufficient for making any definite conclusions. Further studies are needed to establish the role of hamstring muscle in SI joint stability.

  2. LOWER EXTREMITY HYPERMOBILITY, BUT NOT CORE MUSCLE ENDURANCE INFLUENCES BALANCE IN FEMALE COLLEGIATE DANCERS.

    PubMed

    Ambegaonkar, Jatin P; Cortes, Nelson; Caswell, Shane V; Ambegaonkar, Gautam P; Wyon, Matthew

    2016-04-01

    Dance is a physically demanding activity, with almost 70% of all injuries in dancers occurring in the lower extremity (LE). Prior researchers report that muscle function (e.g. muscle endurance) and anatomical factors (e.g. hypermobility) affect physical performance (e.g. balance) and can subsequently influence LE injury risk. Specifically, lesser core muscle endurance, balance deficits, and greater hypermobility are related to increased LE injury risk. However, the potentials interrelationships among these factors in dancers remain unclear. The purposes of this study were to examine the relationships among core muscle endurance, balance, and LE hypermobility, and determine the relative contributions of core muscle endurance and LE hypermobility as predictors of balance in female collegiate dancers. Cross-sectional. Core muscle endurance was evaluated using the combined average anterior, left, and right lateral plank test time scores(s). LE hypermobility was measured using the LE-specific Beighton hypermobility measure, defining hypermobility if both legs had greater than 10 ° knee hyperextension. Balance was measured via the composite anterior, posterolateral, and posteromedial Star Excursion Balance Test (SEBT) reach distances (normalized to leg length) in 15 female healthy collegiate dancers (18.3 + 0.5yrs, 165.5 + 6.9cm, 63.7 + 12.1kg). Point-biserial-correlation-coefficients examined relationships and a linear regression examined whether core endurance and hypermobility predicted balance (p<.05). LE hypermobility (Yes; n = 3, No; n = 12) and balance (87.2 + 8.3% leg length) were positively correlated r(14)=.67, (p=.01). However, core endurance (103.9 + 50.6 s) and balance were not correlated r(14)=.32, (p=.26). LE hypermobility status predicted 36.9% of the variance in balance scores (p=.01). LE hypermobility, but not core muscle endurance may be related to balance in female collegiate dancers. While LE hypermobility status influenced

  3. LOWER EXTREMITY HYPERMOBILITY, BUT NOT CORE MUSCLE ENDURANCE INFLUENCES BALANCE IN FEMALE COLLEGIATE DANCERS

    PubMed Central

    Cortes, Nelson; Caswell, Shane V.; Ambegaonkar, Gautam P.; Wyon, Matthew

    2016-01-01

    Background Dance is a physically demanding activity, with almost 70% of all injuries in dancers occurring in the lower extremity (LE). Prior researchers report that muscle function (e.g. muscle endurance) and anatomical factors (e.g. hypermobility) affect physical performance (e.g. balance) and can subsequently influence LE injury risk. Specifically, lesser core muscle endurance, balance deficits, and greater hypermobility are related to increased LE injury risk. However, the potentials interrelationships among these factors in dancers remain unclear. Purpose The purposes of this study were to examine the relationships among core muscle endurance, balance, and LE hypermobility, and determine the relative contributions of core muscle endurance and LE hypermobility as predictors of balance in female collegiate dancers. Study Design Cross-sectional Methods Core muscle endurance was evaluated using the combined average anterior, left, and right lateral plank test time scores(s). LE hypermobility was measured using the LE-specific Beighton hypermobility measure, defining hypermobility if both legs had greater than 10 ° knee hyperextension. Balance was measured via the composite anterior, posterolateral, and posteromedial Star Excursion Balance Test (SEBT) reach distances (normalized to leg length) in 15 female healthy collegiate dancers (18.3 + 0.5yrs, 165.5 + 6.9cm, 63.7 + 12.1kg). Point-biserial-correlation-coefficients examined relationships and a linear regression examined whether core endurance and hypermobility predicted balance (p<.05). Results LE hypermobility (Yes; n = 3, No; n = 12) and balance (87.2 + 8.3% leg length) were positively correlated r(14)=.67, (p=.01). However, core endurance (103.9 + 50.6 s) and balance were not correlated r(14)=.32, (p=.26). LE hypermobility status predicted 36.9% of the variance in balance scores (p=.01). Conclusion LE hypermobility, but not core muscle endurance may be related to balance in female

  4. Exploring the Link between Serum Phosphate Levels and Low Muscle Strength, Dynapenia, and Sarcopenia.

    PubMed

    Chen, Yuan-Yuei; Kao, Tung-Wei; Chou, Cheng-Wai; Wu, Chen-Jung; Yang, Hui-Fang; Lai, Ching-Huang; Wu, Li-Wei; Chen, Wei-Liang

    2018-02-23

    Emerging evidences addressed an association between phosphate and muscle function. Because little attention was focused on this issue, the objective of our study was to explore the relationship of phosphate with muscle strength, dynapenia, and sarcopenia. From the National Health and Nutrition Examination Survey, a total of 7421 participants aged 20 years or older were included in our study with comprehensive examinations included anthropometric parameters, strength of the quadriceps muscle, and appendicular lean masses. Within the normal range of serum phosphate, we used quartile-based analyses to determine the potential relationships of serum phosphate with dynapenia, and sarcopenia through multivariate regression models. After adjusting for the pertinent variables, an inverse association between the serum phosphate quartiles and muscle strength was observed and the linear association was stronger than other anthropometric parameters. Notably, the significant association between phosphate and muscle strength was existed in >65 years old age group, not in 20-65 years old. The higher quartiles of phosphate had higher likelihood for predicting the presence of dynapenia rather than sarcopenia in entire population. Our study highlighted that higher quartiles of phosphate had significant association with lower muscle strength and higher risks for predicting the presence of dynapenia.

  5. Recovery of strength is dependent on mTORC1 signaling after eccentric muscle injury.

    PubMed

    Baumann, Cory Walter; Rogers, Russell George; Otis, Jeffrey Scott; Ingalls, Christopher Paul

    2016-11-01

    Eccentric contractions may cause immediate and long-term reductions in muscle strength that can be recovered through increased protein synthesis rates. The purpose of this study was to determine whether the mechanistic target-of-rapamycin complex 1 (mTORC1), a vital controller of protein synthesis rates, is required for return of muscle strength after injury. Isometric muscle strength was assessed before, immediately after, and then 3, 7, and 14 days after a single bout of 150 eccentric contractions in mice that received daily injections of saline or rapamycin. The bout of eccentric contractions increased the phosphorylation of mTORC1 (1.8-fold) and p70s6k1 (13.8-fold), mTORC1's downstream effector, 3 days post-injury. Rapamycin blocked mTORC1 and p70s6k1 phosphorylation and attenuated recovery of muscle strength (∼20%) at 7 and 14 days. mTORC1 signaling is instrumental in the return of muscle strength after a single bout of eccentric contractions in mice. Muscle Nerve 54: 914-924, 2016. © 2016 Wiley Periodicals, Inc.

  6. Role of maximal inspiratory presure in the evaluetion of respiratory muscle strength in asthmatics - Systematic review.

    PubMed

    Cavalcante Marcelino, Alessandra M F; da Silva, Hilton Justino

    2010-01-01

    Asthma is a chronic illness of the airways that can reduce respiratory muscle strength due to the resulting hyperinflation or treatment with corticosteroids. One of the ways to evaluate this respiratory muscular weakness is the Maximal Inspiratory Pressure (PImax). A systematic review of the databases PUBMED/MEDLINE, LILACS and SCIELO was carried through, using the key words: Asthma, respiratory muscle and muscle strength. Fifty were found and six articles that evaluated the PImax in asthmatics, from these, thirty were excluded, making a total of twenty six articles. Through the present revision we show the effectiveness of PImax in evaluating respiratory muscle strength in asthmatics. More studies are needed, however, fot better understanding of the asthmatic individual. Rev Port Pneumol 2010; XVI (3): 463-470. © 2010 Sociedade Portuguesa de Pneumologia/SPP.

  7. Relationship between agility and lower limb muscle strength, targeting university badminton players.

    PubMed

    Sonoda, Takuya; Tashiro, Yuto; Suzuki, Yusuke; Kajiwara, Yu; Zeidan, Hala; Yokota, Yuki; Kawagoe, Mirei; Nakayama, Yasuaki; Bito, Tsubasa; Shimoura, Kanako; Tatsumi, Masataka; Nakai, Kengo; Nishida, Yuichi; Yoshimi, Soyoka; Aoyama, Tomoki

    2018-02-01

    [Purpose] Targeting university badminton players, this study investigated the relationship between agility, which is associated with performance in badminton, and lower limb muscle strength, and examined which muscles influence agility. [Subjects and Methods] A total of 23 male university badminton players were evaluated for side-shuffle test scores and lower limb strength. The relationships between agility, lower limb strength, and duration of experience playing badminton were evaluated using a correlation analysis. Moreover, the relationship between agility and lower limb strength was evaluated by partial correlation analysis, adjusting for the effects of experience of each badminton player. [Results] The agility score correlated with hip extension and ankle plantar flexion strength, with adjustment for badminton experience. [Conclusion] This study suggests that hip extension training and improvement in ankle plantar flexion strength may improve agility.

  8. Semimembranosus Release for Medial Soft Tissue Balancing Does Not Weaken Knee Flexion Strength in Patients Undergoing Varus Total Knee Arthroplasty.

    PubMed

    Jang, Sung Won; Koh, In Jun; Kim, Man Soo; Kim, Ju Yeong; In, Yong

    2016-11-01

    The sequential medial release technique including semimembranosus (semiM) release is effective and safe during varus total knee arthroplasty (TKA). However, there are concerns about weakening of knee flexion strength after semiM release. We determined whether semiM release to balance the medial soft tissue decreased knee flexion strength after TKA. Fifty-nine consecutive varus knees undergoing TKA were prospectively enrolled. A 3-step sequential release protocol which consisted of release of (1) the deep medial collateral ligament (dMCL), (2) the semiM, and (3) the superficial medial collateral ligament based on medial tightness. Gap balancing was obtained after dMCL release in 31 knees. However, 28 knees required semiM release or more after dMCL release. Isometric muscle strength of the knee was compared 6 months postoperatively between the semiM release and semiM nonrelease groups. Knee stability and clinical outcomes were also compared. No differences in knee flexor or extensor peak torque were observed between the groups 6 months postoperatively (P = .322 and P = .383, respectively). No group difference was observed in medial joint opening angle on valgus stress radiographs (P = .327). No differences in the Knee Society or Western Ontario and McMaster Universities Osteoarthritis Index scores were detected between the groups (P = .840 and P = .682, respectively). These results demonstrate that semiM release as a sequential step to balance medial soft tissue in varus knees did not affect knee flexion strength after TKA. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Relationships of muscle strength and bone mineral density in ambulatory children with cerebral palsy.

    PubMed

    Chen, C-L; Lin, K-C; Wu, C-Y; Ke, J-Y; Wang, C-J; Chen, C-Y

    2012-02-01

    This work explores the relationships of muscle strength and areal bone mineral density (aBMD) in ambulatory children with cerebral palsy (CP). The knee extensor strength, but not motor function, was related to aBMD. Thus, muscle strength, especially antigravity muscle strength, was more associated with aBMD in these children than motor function. Muscle strength is related to bone density in normal children. However, no studies have examined these relationships in ambulatory children with CP. This work explores the relationships of muscle strength and aBMD in ambulatory children with CP. Forty-eight ambulatory children with spastic CP, aged 5-15 years, were classified into two groups based on Gross Motor Function Classification System levels: I (n = 28) and II (n = 20). Another 31 normal development (ND) children were recruited as the comparison group for the aBMD. Children with CP underwent assessments of growth, lumbar and distal femur aBMD, Gross Motor Function Measure-66 (GMFM-66), and muscle strength of knee extensor and flexor by isokinetic dynamometer. The distal femur aBMD, but not lumbar aBMD, was lower in children with CP than in ND children (p < 0.05). Children with level I had greater knee flexor strength and GMFM-66 scores than those with level II (p < 0.001). However, the knee extensor strength and distal femur and lumbar aBMD did not differ between two groups. Regression analysis revealed the weight and knee extensor strength, but not GMFM-66 scores, were related positively to the distal femur and lumbar aBMD (adjusted r (2) = 0.56-0.65, p < 0.001). These results suggest the muscle strength, especially antigravity muscle strength, were more associated with the bone density of ambulatory children with CP than motor function. The data may allow clinicians for early identifying the ambulatory CP children of potential low bone density.

  10. Blockade of Metallothioneins 1 and 2 Increases Skeletal Muscle Mass and Strength

    PubMed Central

    Summermatter, Serge; Bouzan, Anais; Pierrel, Eliane; Melly, Stefan; Stauffer, Daniela; Gutzwiller, Sabine; Nolin, Erin; Dornelas, Christina; Fryer, Christy; Leighton-Davies, Juliet; Glass, David J.

    2016-01-01

    ABSTRACT Metallothioneins are proteins that are involved in intracellular zinc storage and transport. Their expression levels have been reported to be elevated in several settings of skeletal muscle atrophy. We therefore investigated the effect of metallothionein blockade on skeletal muscle anabolism in vitro and in vivo. We found that concomitant abrogation of metallothioneins 1 and 2 results in activation of the Akt pathway and increases in myotube size, in type IIb fiber hypertrophy, and ultimately in muscle strength. Importantly, the beneficial effects of metallothionein blockade on muscle mass and function was also observed in the setting of glucocorticoid addition, which is a strong atrophy-inducing stimulus. Given the blockade of atrophy and the preservation of strength in atrophy-inducing settings, these results suggest that blockade of metallothioneins 1 and 2 constitutes a promising approach for the treatment of conditions which result in muscle atrophy. PMID:27956698

  11. Mind-muscle connection training principle: influence of muscle strength and training experience during a pushing movement.

    PubMed

    Calatayud, Joaquin; Vinstrup, Jonas; Jakobsen, Markus D; Sundstrup, Emil; Colado, Juan Carlos; Andersen, Lars L

    2017-07-01

    To investigate the effect of different attentional focus conditions on muscle activity during the push-up exercise and to assess the possible influence of muscle strength and training experience. Eighteen resistance-trained men performed 1RM bench press testing and were familiarized with the procedure during the first session. In the second session, three different conditions were randomly performed: regular push-up and push-up focusing on using the pectoralis major and triceps brachii muscles, respectively. Surface electromyography (EMG) was recorded and analyzed (EMG normalized to max; nEMG) for the triceps brachii and pectoralis major muscles. Participants had on average 8 (SD 6) years of training experience and 1RM of 1.25 (SD 0.28) kg per kg bodyweight. Focusing on using pectoralis major increased activity in this muscle by 9% nEMG (95% CI 5-13; Cohen's d 0.60) compared with the regular condition. Triceps activity was not significantly influenced by triceps focus although borderline significant, with a mean difference of 5% nEMG (95% CI 0-10; Cohen's d 0.30). However, years of training experience was positively associated with the ability to selectively activate the triceps (β = 0.41, P = 0.04), but not the pectoralis. Bench press 1RM was not significantly associated with the ability to selectively activate the muscles. Pectoralis activity can be increased when focusing on using this muscle during push-ups, whereas the ability to do this for the triceps is dependent on years of training experience. Maximal muscle strength does not appear to be a decisive factor for the ability to selectively activate these muscles.

  12. Reference values for muscle strength: a systematic review with a descriptive meta-analysis.

    PubMed

    Benfica, Poliana do Amaral; Aguiar, Larissa Tavares; Brito, Sherindan Ayessa Ferreira de; Bernardino, Luane Helena Nunes; Teixeira-Salmela, Luci Fuscaldi; Faria, Christina Danielli Coelho de Morais

    2018-05-03

    Muscle strength is an important component of health. To describe and evaluate the studies which have established the reference values for muscle strength on healthy individuals and to synthesize these values with a descriptive meta-analysis approach. A systematic review was performed in MEDLINE, LILACS, and SciELO databases. Studies that investigated the reference values for muscle strength of two or more appendicular/axial muscle groups of health individuals were included. Methodological quality, including risk of bias was assessed by the QUADAS-2. Data extracted included: country of the study, sample size, population characteristics, equipment/method used, and muscle groups evaluated. Of the 414 studies identified, 46 were included. Most of the studies had adequate methodological quality. Included studies evaluated: appendicular (80.4%) and axial (36.9%) muscles; adults (78.3%), elderly (58.7%), adolescents (43.5%), children (23.9%); isometric (91.3%) and isokinetic (17.4%) strength. Six studies (13%) with similar procedures were synthesized with meta-analysis. Generally, the coefficient of variation values that resulted from the meta-analysis ranged from 20.1% to 30% and were similar to those reported by the original studies. The meta-analysis synthesized the reference values of isometric strength of 14 muscle groups of the dominant/non-dominant sides of the upper/lower limbs of adults/elderly from developed countries, using dynamometers/myometer. Most of the included studies had adequate methodological quality. The meta-analysis provided reference values for the isometric strength of 14 appendicular muscle groups of the dominant/non-dominant sides, measured with dynamometers/myometers, of men/women, of adults/elderly. These data may be used to interpret the results of the evaluations and establish appropriate treatment goals. Copyright © 2018 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights

  13. FKBP12 deficiency reduces strength deficits after eccentric contraction-induced muscle injury

    PubMed Central

    Corona, Benjamin T.; Rouviere, Clement; Hamilton, Susan L.; Ingalls, Christopher P.

    2008-01-01

    Strength deficits associated with eccentric contraction-induced muscle injury stem, in part, from excitation-contraction uncoupling. FKBP12 is a 12-kDa binding protein known to bind to the skeletal muscle sarcoplasmic reticulum Ca2+ release channel [ryanodine receptor (RyR1)] and plays an important role in excitation-contraction coupling. To assess the effects of FKBP12 deficiency on muscle injury and recovery, we measured anterior crural muscle (tibialis anterior and extensor digitorum longus muscles) strength in skeletal muscle-specific FKBP12-deficient and wild-type (WT) mice before and after a single bout of 150 eccentric contractions, as well as before and after the performance of six injury bouts. Histological damage of the tibialis anterior muscle was assessed after injury. Body weight and peak isometric and eccentric torques were lower in FKBP12-deficient mice compared with WT mice. There were no differences between FKBP12-deficient and WT mice in preinjury peak isometric and eccentric torques when normalized to body weight, and no differences in the relative decreases in eccentric torque with a single or multiple injury bouts. After a single injury bout, FKBP12-deficient mice had less initial strength deficits and recovered faster (especially females) than WT mice, despite no differences in the degree of histological damage. After multiple injury bouts, FKBP12-deficient mice recovered muscle strength faster than WT mice and exhibited significantly less histological muscle damage than WT mice. In summary, FKBP12 deficiency results in less initial strength deficits and enhanced recovery from single (especially females) and repeated bouts of injury than WT mice. PMID:18511525

  14. [Correlations Between Joint Proprioception, Muscle Strength, and Functional Ability in Patients with Knee Osteoarthritis].

    PubMed

    Chen, Yoa; Yu, Yong; He, Cheng-qi

    2015-11-01

    To establish correlations between joint proprioception, muscle flexion and extension peak torque, and functional ability in patients with knee osteoarthritis (OA). Fifty-six patients with symptomatic knee OA were recruited in this study. Both proprioceptive acuity and muscle strength were measured using the isomed-2000 isokinetic dynamometer. Proprioceptive acuity was evaluated by establishing the joint motion detection threshold (JMDT). Muscle strength was evaluated by Max torque (Nm) and Max torque/weight (Nm/ kg). Functional ability was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index physical function (WOMAC-PF) questionnaire. Correlational analyses were performed between proprioception, muscle strength, and functional ability. A multiple stepwise regression model was established, with WOMAC-PF as dependent variable and patient age, body mass index (BMI), visual analogue scale (VAS)-score, mean grade for Kellgren-Lawrance of both knees, mean strength for quadriceps and hamstring muscles of both knees, and mean JMDT of both knees as independent variables. Poor proprioception (high JMDT) was negatively correlated with muscle strength (P<0.05). There was no significant correlation between knee proprioception (high JMDT) and joint pain (WOMAC pain score), and between knee proprioception (high JMDT) and joint stiffness (WOMAC stiffness score). Poor proprioception (high JMDT) was correlated with limitation in functional ability (WOMAC physical function score r=0.659, P<0.05). WOMAC score was correlated with poor muscle strength (quadriceps muscle strength r = -0.511, P<0.05, hamstring muscle strength r = -0.408, P<0.05). The multiple stepwise regression model showed that high JMDT C standard partial regression coefficient (B) = 0.385, P<0.50 and high VAS-scale score (B=0.347, P<0.05) were significant predictors of WOMAC-PF score. Patients with poor proprioception is associated with poor muscle strength and limitation in functional

  15. Endogenous hormones, muscle strength, and risk of fall-related fractures in older women.

    PubMed

    Sipilä, Sarianna; Heikkinen, Eino; Cheng, Sulin; Suominen, Harri; Saari, Päivi; Kovanen, Vuokko; Alén, Markku; Rantanen, Taina

    2006-01-01

    Among older people, fracture-causing fall often leads to health deterioration. The role of endogenous hormone status and muscle strength on fall-related fracture risk is unclear. This study investigates if, after adjustment for bone density, endogenous hormones and muscle strength would predict fall-related limb fracture incidence in older community-dwelling women followed-up over 10 years. As a part of a prospective population-based study, 187 75-year-old women were investigated. Serum estradiol, testosterone, sex hormone binding globulin, and dehydroepiandrosterone sulfate concentrations were analyzed, and isometric muscle strength and bone mineral density were assessed. Fall-related limb fractures were gathered from patient records. Serum estradiol concentration was a significant predictor of fall-related limb fractures. Women with serum estradiol concentrations less than 0.022 nmol/L had a 3-fold risk (relative risk 3.05; 95% confidence interval, 1.26-7.36), and women with estradiol concentrations between 0.022 and 0.066 nmol/L doubled the risk (relative risk 2.24; 95% confidence interval, 0.97-5.19) of fall-related limb fracture compared to the women with estradiol concentrations ()above 0.066 nmol/L. Adjustment for muscle strength and bone mineral density did not materially change the risk estimates. High muscle strength was associated with a low incidence of fall-related limb fractures. This study showed that in 75-year-old women higher serum estradiol concentration and greater muscle strength were independently associated with a low incidence of fall-related limb fractures even after adjustment for bone density. Our results suggest that hormonal status and muscle strength have their own separate mechanisms protecting from fall-related fractures. This finding is of importance in developing preventive strategies, but calls for further study.

  16. [Evolution in muscle strength in critical patients with invasive mechanical ventilation].

    PubMed

    Via Clavero, G; Sanjuán Naváis, M; Menéndez Albuixech, M; Corral Ansa, L; Martínez Estalella, G; Díaz-Prieto-Huidobro, A

    2013-01-01

    To assess the evolution of muscle strength in critically ill patients with mechanical ventilation (MV) from withdrawal of sedatives to hospital discharge. A cohort study was conducted in two intensive care units in the Hospital Universitari de Bellvitge from November 2011 to March 2012. Consecutive patients with MV > 72h. Dependent outcome: Muscle strength measured with the Medical Research Council (MRC) scale beginning on the first day the patient was able to answer 3 out of 5 simple orders (day 1), every week, at ICU discharge and at hospital discharge or at day 60 Independent outcomes: factors associated with muscle strength loss, ventilator-free days, ICU length of stay and hospital length of stay. The patients were distributed into two groups (MRC< 48, MRC ≥ 48) after the first measurement. Thirty-four patients were assessed. Independent outcomes associated with muscle strength weakness were: days with cardiovascular SOFA >2 (P<.001) and days with costicosteroids (P<.001). Initial MRC in MRC<48 group was 38 (27-43), and 52 (50-54) in MRC ≥ 48. The largest muscle strength gain was obtained the first week (31% versus 52%). A MRC < 48 value was associated with more MV days (P<.007) and a longer ICU stay. (P<.003). The greatest muscle strength gain after withdrawing of the sedatives was achieved in the first week. Muscle strength loss was associated with a cardiovascular SOFA > 2 and costicosteroids. Patients with a MRC < 48 required more days with MV and a longer ICU stay. Copyright © 2013 Elsevier España, S.L. y SEEIUC. All rights reserved.

  17. Normal reference values of strength in pelvic floor muscle of women: a descriptive and inferential study.

    PubMed

    Chevalier, Francine; Fernandez-Lao, Carolina; Cuesta-Vargas, Antonio Ignacio

    2014-11-25

    To describe the clinical, functional and quality of life characteristics in women with Stress Urinary Incontinence (SUI). In addition, to analyse the relationship between the variables reported by the patients and those informed by the clinicians, and the relationship between instrumented variables and the manual pelvic floor strength assessment. Two hundred and eighteen women participated in this observational, analytical study. An interview about Urinary Incontinence and the quality of life questionnaires (EuroQoL-5D and SF-12) were developed as outcomes reported by the patients. Manual muscle testing and perineometry as outcomes informed by the clinician were assessed. Descriptive and correlation analysis were carried out. The average age of the subjects was (39.93 ± 12.27 years), (24.49 ± 3.54 BMI). The strength evaluated by manual testing of the right levator ani muscles was 7.79 ± 2.88, the strength of left levator ani muscles was 7.51 ± 2.91 and the strength assessed with the perineometer was 7.64 ± 2.55. A positive correlation was found between manual muscle testing and perineometry of the pelvic floor muscles (p < .001). No correlation was found between outcomes of quality of life reported by the patients and outcomes of functional capacity informed by the physiotherapist. A stratification of the strength of pelvic floor muscles in a normal distribution of a large sample of women with SUI was done, which provided the clinic with a baseline. There is a relationship between the strength of the pelvic muscles assessed manually and that obtained by a perineometer in women with SUI. There was no relationship between these values of strength and quality of life perceived.

  18. Shank Muscle Strength Training Changes Foot Behaviour during a Sudden Ankle Supination

    PubMed Central

    Hagen, Marco; Lescher, Stephanie; Gerhardt, Andreas; Lahner, Matthias; Felber, Stephan; Hennig, Ewald M.

    2015-01-01

    Background The peroneal muscles are the most effective lateral stabilisers whose tension braces the ankle joint complex against excessive supination. The purpose of this study was to identify the morphological and biomechanical effects of two machine-based shank muscle training methods. Methods Twenty-two healthy male recreationally active sports students performed ten weeks of single-set high resistance strength training with 3 training sessions per week. The subjects conducted subtalar pronator/supinator muscle training (ST) with the right leg by using a custom-made apparatus; the left foot muscles were exercised with machine-based talocrural plantar and dorsiflexor training (TT). Muscle strength (MVIC), muscle volume and foot biomechanics (rearfoot motion, ground reaction forces, muscle reaction times) during a sudden ankle supination were recorded before and after the intervention. Results Compared to TT, ST resulted in significantly higher pronator (14% vs. 8%, P<0.01) and supinator MVIC (25% vs. 12%, P<0.01). During sudden foot inversions, both ST and TT resulted in reduced supination velocity (-12%; P<0.01). The muscle reaction onset time was faster after the training in peroneus longus (PL) (P<0.01). Muscle volume of PL (P<0.01) and TA (P<0.01) increased significantly after both ST and TT. Conclusion After both ST and TT, the ankle joint complex is mechanically more stabilised against sudden supinations due to the muscle volume increase of PL and TA. As the reduced supination velocities indicate, the strength training effects are already present during free-fall. According to a sudden ankle supination in standing position, both machine-based dorsiflexor and pronator strength training is recommended for enhancing the mechanical stability of the ankle. PMID:26110847

  19. Achilles tendinosis and calf muscle strength. The effect of short-term immobilization after surgical treatment.

    PubMed

    Alfredson, H; Pietilä, T; Ohberg, L; Lorentzon, R

    1998-01-01

    We prospectively studied calf muscle strength in 7 men and 4 women (mean age, 40.9 +/- 10.1 years) who had surgical treatment for chronic Achilles tendinosis. Surgery was followed by immobilization in a weightbearing below-the-knee plaster cast for 2 weeks followed by a stepwise increasing strength training program. Strength measurements (peak torque and total work) were done preoperatively (Week 0) and at 16, 26, and 52 weeks postoperatively. We measured isokinetic concentric plantar flexion strength at 90 and 225 deg/sec and eccentric flexion strength at 90 deg/sec on both the injured and noninjured sides. Preoperatively, concentric and eccentric strength were significantly lower on the injured side at 90 and 225 deg/sec. Postoperatively, concentric peak torque on the injured side decreased significantly between Weeks 0 and 16 and increased significantly between Weeks 26 and 52 at 90 deg/sec but was significantly lower than that on the noninjured side at all periods and at both velocities. The eccentric strength was significantly lower on the injured side at Week 26 but increased significantly until at Week 52 no significant differences between the sides could be demonstrated. It seems, therefore, that the recovery in concentric and eccentric calf muscle strength after surgery for Achilles tendinosis is slow. We saw no obvious advantages in recovery of muscle strength with a short immobilization time (2 weeks) versus a longer (6 weeks) period used in a previous study.

  20. Effects of the lower extremities muscle activation during muscular strength training on an unstable platform with magneto-rheological dampers

    NASA Astrophysics Data System (ADS)

    Piao, YongJun; Choi, YounJung; Kim, JungJa; Kwan, TaeKyu; Kim, Nam-Gyun

    2009-03-01

    Adequate postural balance depends on the spatial and temporal integration of vestibular, visual, and somatosensory information. Especially, the musculoskeletal function (range of joint, flexibility of spine, muscular strength) is essential in maintaining the postural balance. Muscular strength training methods include the use of commercialized devices and repeatable resistance training tools (rubber band, ball, etc). These training systems cost high price and can't control of intensity. Thus we suggest a new training system which can adjust training intensity and indicate the center of pressure of a subject while the training was passively controlled by applying controlled electric current to the Magneto- Rheological damper. And we performed experimental studies on the muscular activities in the lower extremities during maintaining, moving and pushing exercises on an unstable platform with Magneto rheological dampers. A subject executed the maintaining, moving and pushing exercises which were displayed in a monitor. The electromyographic signals of the eight muscles in lower extremities were recorded and analyzed in the time and frequency domain: the muscles of interest were rectus femoris, biceps femoris, tensor fasciae latae, vastus lateralis, vastus medialis, gastrocnemius, tibialis anterior, and soleus. The experimental results showed the difference of muscular activities at the four moving exercises and the nine maintaining exercises. The rate of the increase in the muscular activities was affected by the condition of the unstable platform with MR dampers for the maintaining and moving exercises. The experimental results suggested the choice of different maintaining and moving exercises could selectively train different muscles with varying intensity. Furthermore, the findings also suggested the training using this system can improve the ability of postural balance.

  1. Strength, power output and symmetry of leg muscles: effect of age and history of falling.

    PubMed

    Perry, Mark C; Carville, Serena F; Smith, I Christopher H; Rutherford, Olga M; Newham, Di J

    2007-07-01

    Risk factors for medically unexplained falls may include reduced muscle power, strength and asymmetry in the lower limbs. Conflicting reports exist about strength and there is little information about power and symmetry. Forty-four healthy young people (29.3 +/- 0.6 years), 44 older non-fallers (75.9 +/- 0.6 years), and 34 older fallers (76.4 +/- 0.8 years) were studied. Isometric, concentric and eccentric strength of the knee and ankle muscles and leg extension power were measured bilaterally. The younger group was stronger in all muscles and types of contraction than both older groups (P < 0.02-0.0001). Strength differences between the older groups occasionally reached significance in individual muscles and types of contraction but overall the fallers had 85% of the strength and 79% of the power of the non-fallers (P < 0.001). Young subjects generated more power than both older groups (P < 0.0001) and the fallers generated less than the non-fallers (P = 0.03). Strength symmetry showed an inconsistent age effect in some muscles and some contraction types. This was similar overall in the two older groups. Both older groups had greater asymmetry in power than the young (P < 0.02-0.004). Power asymmetry tended to be greater in the fallers than the non-fallers but this did not reach significance. These data do not support the suggestion that asymmetry of strength and power are associated with either increasing age or fall history. Power output showed clear differences between age groups and fall status and appears to be the most relevant measurement of fall risk and highlights the cumulative effects on function of small changes in strength in individual muscle groups.

  2. Strength characterization of knee flexor and extensor muscles in Prader-Willi and obese patients.

    PubMed

    Capodaglio, Paolo; Vismara, Luca; Menegoni, Francesco; Baccalaro, Gabriele; Galli, Manuela; Grugni, Graziano

    2009-05-06

    despite evidence of an obesity-related disability, there is a lack of objective muscle functional data in overweight subjects. Only few studies provide instrumental strength measurements in non-syndromal obesity, whereas no data about Prader-Willi syndrome (PWS) are reported. The aim of our study was to characterize the lower limb muscle function of patients affected by PWS as compared to non-syndromal obesity and normal-weight subjects. We enrolled 20 obese (O) females (age: 29.1 +/- 6.5 years; BMI: 38.1 +/- 3.1), 6 PWS females (age: 27.2 +/- 4.9 years; BMI: 45.8 +/- 4.4) and 14 healthy normal-weight (H) females (age: 30.1 +/- 4.7 years; BMI: 21 +/- 1.6). Isokinetic strength during knee flexion and extension in both lower limbs at the fixed angular velocities of 60 degrees /s, 180 degrees /s, 240 degrees /s was measured with a Cybex Norm dynamometer. the H, O and PWS populations appear to be clearly stratified with regard to muscle strength.: PWS showed the lowest absolute peak torque (PT) for knee flexor and extensor muscles as compared to O (-55%) and H (-47%) (P = 0.00001). O showed significantly higher strength values than H as regard to knee extension only (P = 0.0014). When strength data were normalised by body weight, PWS showed a 50% and a 70% reduction in PT as compared to O and H, respectively. Knee flexors strength values were on average half of those reported for extension in all of the three populations. the novel aspect of our study is the determination of objective measures of muscle strength in PWS and the comparison with O and H patients. The objective characterization of muscle function performed in this study provides baseline and outcome measures that may quantify specific strength deficits amendable with tailored rehabilitation programs and monitor effectiveness of treatments.

  3. Positive effects of 1-year football and strength training on mechanical muscle function and functional capacity in elderly men.

    PubMed

    Sundstrup, Emil; Jakobsen, Markus Due; Andersen, Lars Louis; Andersen, Thomas Rostgaard; Randers, Morten Bredsgaard; Helge, Jørn Wulff; Suetta, Charlotte; Schmidt, Jakob Friis; Bangsbo, Jens; Krustrup, Peter; Aagaard, Per

    2016-06-01

    A decline in physical capacity takes place with increasing age that negatively affects overall physical function including work ability and the ability to perform typical activities of daily living (ADL). The overall aim of the present study was to determine the neuromuscular adaptations to long-term (1 year) football and strength training in older untrained adults, and to assess the concurrent effect on functional ADL capacity. Twenty-seven healthy elderly males (68.2 ± 3.2 years) were randomly assigned to 12 months of either recreational football training (FT: n = 10), strength training (ST: n = 9) or served as inactive controls (CON: n = 8). Recreational football training consisted of small-sided training sessions whereas strength training consisted of high intensity exercises targeting the lower extremity and upper body. Maximal thigh muscle strength and rate of force development (RFD) were assessed with isokinetic dynamometry, while postural balance and vertical jumping performance were evaluated using force plate analysis. Furthermore, functional ability was evaluated by stair-ascent and chair-rising testing. A total of nine, nine and seven participants from FT, ST and CON, respectively, were included in the analysis. Both exercise regimens led to substantial gains in functional ability, evidenced by 24 and 18 % reduced stair-ascent time, and 32 and 21 % increased chair-rising performance in FT and ST, respectively (all P < 0.05). Long-term strength training led to increased concentric (14 %; P < 0.01) and isometric (23 %; P < 0.001) quadriceps and isometric hamstring strength (44 %; P < 0.0001), whereas football training mainly resulted in enhanced hamstring strength (18 %, P < 0.05) and RFD (89 %, P < 0.0001). Long-term (1 year) strength training led to increased quadriceps and hamstring strength, whereas the adaptations to football training mainly included enhanced strength and rapid force capacity of the hamstring muscles

  4. Diaphragm Plasticity in Aging and Disease: Therapies for Muscle Weakness go from Strength to Strength.

    PubMed

    Greising, Sarah M; Ottenheijm, Coen A C; O'Halloran, Ken D; Barreiro, Esther

    2018-04-19

    The diaphragm is the main inspiratory muscle and is required to be highly active throughout the lifespan. The diaphragm muscle must be able to produce and sustain various behaviors that range from ventilatory to non-ventilatory such as those required for airway maintenance and clearance. Throughout the lifespan various circumstances and conditions may affect the ability of the diaphragm muscle to generate requisite forces and in turn the diaphragm muscle may undergo significant weakness and dysfunction. For example, hypoxic stress, critical illness, cancer cachexia, chronic obstructive pulmonary disorder (COPD), and age-related sarcopenia all represent conditions in which significant diaphragm muscle dysfunction exits. This perspective review article presents several interesting topics involving diaphragm plasticity in aging and disease that were presented at the International Union of Physiological Sciences (IUPS) Conference in 2017.This review seeks to maximize the broad and collective research impact on diaphragm muscle dysfunction in the search for transformative treatment approaches to improve the diaphragm muscle health during aging and disease.

  5. Isometric muscle strength and mobility capacity in children with cerebral palsy.

    PubMed

    Dallmeijer, Annet J; Rameckers, Eugene A; Houdijk, Han; de Groot, Sonja; Scholtes, Vanessa A; Becher, Jules G

    2017-01-01

    To determine the relationship between isometric leg muscle strength and mobility capacity in children with cerebral palsy (CP) compared to typically developing (TD) peers. Participants were 62 children with CP (6-13 years), able to walk with (n = 10) or without (n = 52) walking aids, and 47 TD children. Isometric muscle strength of five muscle groups of the leg was measured using hand-held dynamometry. Mobility capacity was assessed with the 1-min walk, the 10-m walk, sit-to-stand, lateral-step-up and timed-stair tests. Isometric strength of children with CP was reduced to 36-82% of TD. When adjusted for age and height, the percentage of variance in mobility capacity that was explained by isometric strength of the leg muscles was 21-24% (walking speed), 25% (sit-to-stand), 28% (lateral-step-up) and 35% (timed-stair) in children with CP. Hip abductors and knee flexors had the largest contribution to the explained variance, while knee extensors showed the weakest correlation. Weak or no associations were found between strength and mobility capacity in TD children. Isometric strength, especially hip abductor and knee flexor strength, is moderately related to mobility capacity in children with CP, but not in TD children. To what extent training of these muscle groups will lead to better mobility capacity needs further study. Implications for Rehabilitation Strength training in children with cerebral palsy (CP) may be targeted more specifically at hip abductors and knee flexors. The moderate associations imply that large improvements in mobility capacity may not be expected when strength increases.

  6. Impact of back muscle strength and aging on locomotive syndrome in community living Japanese women.

    PubMed

    Hirano, Kenichi; Imagama, Shiro; Hasegawa, Yukiharu; Wakao, Norimitsu; Muramoto, Akio; Ishiguro, Naoki

    2013-02-01

    The Japanese Orthopaedic Association has proposed the term locomotive syndrome (LS) to designate a condition of individuals in high-risk groups with musculoskeletal disease who are highly likely to require nursing care. This study investigates the influence of spinal factors on LS in Japanese females. A total of 187 women > or =50 years old were enrolled in the study. Those answering yes to least one of the 7 categories in the self-assessment checklist for LS were defined as having LS. We evaluated lateral lumbar radiographs, sagittal parameters, sagittal balance using the spinal inclination angle (SIA) as an index, spinal range of motion (ROM) as determined with SpinalMouse, back muscle strength (BMS), and body mass index (BMI). Age, BMI, BMS, SIA, sacral slope angle (SSA), and lumbar spinal ROM showed significant correlations with LS. Multiple logistic regression analysis indicated that an increase in age (OR 1.054, p<0.05) and a decrease in BMS (OR 0.968, p<0.01) were significantly associated with LS. Age had significant negative correlations with BMS, SSA, thoracic and lumbar spinal ROM, and it had positive correlations with BMI, SIA, and lumbar kyphosis. BMS had significant negative correlations with age, SIA, thoracic and lumbar kyphosis, and it had positive correlations with SSA, lumbar and total spinal ROM. An increase in age and a decrease in BMS may be the most important risk factors for LS in Japanese women. Back muscle strengthening and spinal ROM exercises could be useful for improving the status of an individual suffering from LS.

  7. Acceleration effects on neck muscle strength: pilots vs. non-pilots.

    PubMed

    Seng, Kok-Yong; Lam, Pin-Min; Lee, Vee-Sin

    2003-02-01

    Conditioning of neck muscles, if any, due to repeated exposures to +Gz forces has received little research attention. This study was conducted to evaluate and compare the neck muscle strength of test volunteers representative of the general populations of fighter aircraft pilots and non-pilots. The tests were performed using a special attachment device on a computerized dynamometer. Ten pilots and ten non-pilots volunteered as test subjects. Each individual's maximal isometric neck muscle strength was evaluated in the extension, flexion, and left and right lateral bending directions in a single day. Peak values from the measurements were used for data analysis. Overall neck strength was calculated as the mean values for the four directions in each group. The overall muscular strength of the necks of pilots did not differ significantly from that of non-pilots, nor did exposure to +Gz forces lead to specific changes in isometric muscle strength across any of the four principal directions. Neck muscle strength in the four measured directions pooled across the two subgroups were statistically significant. The widespread practice of adopting protective head-positioning strategies to minimize neck strains, coupled with results from this research study, suggest that the neck muscles are subjected to reduced in-flight strengthening workouts during exposures to +Gz forces. To maximize in-flight performance and minimize +Gz-induced neck injuries, fighter pilots should be encouraged to perform on-land neck muscle strengthening exercise and in-flight head-positioning techniques. More research is needed to fine-tune this countermeasure strategy against cervical spine injury.

  8. Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy in Resistance-Trained Men.

    PubMed

    Schoenfeld, Brad J; Pope, Zachary K; Benik, Franklin M; Hester, Garrett M; Sellers, John; Nooner, Josh L; Schnaiter, Jessica A; Bond-Williams, Katherine E; Carter, Adrian S; Ross, Corbin L; Just, Brandon L; Henselmans, Menno; Krieger, James W

    2016-07-01

    Schoenfeld, BJ, Pope, ZK, Benik, FM, Hester, GM, Sellers, J, Nooner, JL, Schnaiter, JA, Bond-Williams, KE, Carter, AS, Ross, CL, Just, BL, Henselmans, M, and Krieger, JW. Longer interset rest periods enhance muscle strength and hypertrophy in resistance-trained men. J Strength Cond Res 30(7): 1805-1812, 2016-The purpose of this study was to investigate the effects of short rest intervals normally associated with hypertrophy-type training versus long rest intervals traditionally used in strength-type training on muscular adaptations in a cohort of young, experienced lifters. Twenty-one young resistance-trained men were randomly assigned to either a group that performed a resistance training (RT) program with 1-minute rest intervals (SHORT) or a group that employed 3-minute rest intervals (LONG). All other RT variables were held constant. The study period lasted 8 weeks with subjects performing 3 total body workouts a week comprised 3 sets of 8-12 repetition maximum (RM) of 7 different exercises per session. Testing was performed prestudy and poststudy for muscle strength (1RM bench press and back squat), muscle endurance (50% 1RM bench press to failure), and muscle thickness of the elbow flexors, triceps brachii, and quadriceps femoris by ultrasound imaging. Maximal strength was significantly greater for both 1RM squat and bench press for LONG compared to SHORT. Muscle thickness was significantly greater for LONG compared to SHORT in the anterior thigh, and a trend for greater increases was noted in the triceps brachii (p = 0.06) as well. Both groups saw significant increases in local upper body muscle endurance with no significant differences noted between groups. This study provides evidence that longer rest periods promote greater increases in muscle strength and hypertrophy in young resistance-trained men.

  9. Strength, Multijoint Coordination, and Sensorimotor Processing Are Independent Contributors to Overall Balance Ability

    PubMed Central

    Lawrence, Emily L.; Cesar, Guilherme M.; Bromfield, Martha R.; Peterson, Richard; Valero-Cuevas, Francisco J.; Sigward, Susan M.

    2015-01-01

    For young adults, balance is essential for participation in physical activities but is often disrupted following lower extremity injury. Clinical outcome measures such as single limb balance (SLB), Y-balance (YBT), and the single limb hop and balance (SLHB) tests are commonly used to quantify balance ability following injury. Given the varying demands across tasks, it is likely that such outcome measures provide useful, although task-specific, information. But the extent to which they are independent and contribute to understanding the multiple contributors to balance is not clear. Therefore, the purpose of this study was to investigate the associations among these measures as they relate to the different contributors to balance. Thirty-seven recreationally active young adults completed measures including Vertical Jump, YBT, SLB, SLHB, and the new Lower Extremity Dexterity test. Principal components analysis revealed that these outcome measures could be thought of as quantifying the strength, multijoint coordination, and sensorimotor processing contributors to balance. Our results challenge the practice of using a single outcome measure to quantify the naturally multidimensional mechanisms for everyday functions such as balance. This multidimensional approach to, and interpretation of, multiple contributors to balance may lead to more effective, specialized training and rehabilitation regimens. PMID:26665007

  10. [Comparison of pelvic floor muscle strength in competition-level athletes and untrained women].

    PubMed

    Ludviksdottir, Ingunn; Hardardottir, Hildur; Sigurdardottir, Thorgerdur; Ulfarsson, Gudmundur F

    2018-01-01

    Exercise can stress the pelvic floor muscles. Numerous women experience urinary incontinence while exercising or competing in sports. This study investigated pelvic floor muscle strength, urinary incontinence, and knowledge in contracting pelvic floor muscles among female athletes and untrained women. This was a prospective case-control study measuring pelvic floor muscle strength using vaginal pressure meas-urement. Participants answered questions regarding general health, urinary incontinence, and knowledge on pelvic floor muscles. Partici-pants were healthy nulliparous women aged 18-30 years, athletes and untrained women. The athletes had competed in their sport for at least three years; including handball, soccer, gymnastics, badminton, BootCamp and CrossFit. The women were comparable in age and height. The athletes (n=18) had a body mass index (BMI) of 22.8 kg/m² vs. 25 kg/m² for the untrained (n=16); p<0.05. The athletes trained on average 11.4 hours/week while the untrained women participated in some activity on average for 1.3 hours/week; p< 0.05. Mean pelvic floor strength was 45±2 hPa in the athletes vs. 43±4 hPa in the untrained; p=0.36 for whether the athletes were stronger. Of the athletes, 61.1% experienced urinary incontinence (n=11) compared with 12.5% of the untrained women (n=2); p<0.05. Incontinence usually occurred during high intensity exercise. The athletes were more knowledgeable about the pelvic floor muscles; p<0.05. There was not a significant difference in the strength of pelvic floor muscles of athletes and untrained women. This suggests that pelvic floor muscles are not strengthened during general training but require specific exercises. This holds especially for football, handball and sports with high physical intensity. Coaches need to pay special attention to training and strengthening women's pelvic floor muscles to reduce the occurrence of urinary incontinence.

  11. Effect of eccentric strengthening on pain, muscle strength, endurance, and functional fitness factors in male patients with achilles tendinopathy.

    PubMed

    Yu, JaeHo; Park, DaeSung; Lee, GyuChang

    2013-01-01

    The aim of this study was to investigate the effect of eccentric strengthening on pain, muscle strength, endurance, and functional fitness factors in Achilles tendinopathy patients. Thirty-two male patients with Achilles tendinopathy were assigned to either the experimental group that performed eccentric strengthening or the control group that performed concentric strengthening (n = 16, both groups) for 8 wks (50 mins per day, three times per week). A visual analog scale, an isokinetic muscle testing equipment, the side-step test, and the Sargent jump test were used to assess pain, muscle strength, endurance, and functional fitness factors before and after the intervention. In comparison with the control group, the experimental group showed significant improvement in pain, ankle dorsiflexion endurance, total balance index, and agility after the intervention (P < 0.05). However, there was no significant difference in dexterity between the two groups. Eccentric strengthening was more effective than concentric strengthening in reducing pain and improving function in patients with Achilles tendinopathy; therefore, regular eccentric strengthening is important for patients in a clinical setting.

  12. Effect of strength training with blood flow restriction on muscle power and submaximal strength in eumenorrheic women.

    PubMed

    Gil, Ana L S; Neto, Gabriel R; Sousa, Maria S C; Dias, Ingrid; Vianna, Jeferson; Nunes, Rodolfo A M; Novaes, Jefferson S

    2017-03-01

    Blood flow restriction (BFR) training stimulates muscle size and strength by increasing muscle activation, accumulation of metabolites and muscle swelling. This method has been used in different populations, but no studies have evaluated the effects of training on muscle power and submaximal strength (SS) in accounted for the menstrual cycle. The aim of this study was to analyse the effect of strength training (ST) with BFR on the muscle power and SS of upper and lower limbs in eumenorrheic women. Forty untrained women (18-40 years) were divided randomly and proportionally into four groups: (i) high-intensity ST at 80% of 1RM (HI), (ii) low-intensity ST at 20% of 1RM combined with partial blood flow restriction (LI + BFR), (iii) low-intensity ST at 20% of 1RM (LI) and d) control group (CG). Each training group performed eight training sessions. Tests with a medicine ball (MB), horizontal jump (HJ), vertical jump (VJ), biceps curls (BC) and knee extension (KE) were performed during the 1st day follicular phase (FP), 14th day (ovulatory phase) and 26-28th days (luteal phase) of the menstrual cycle. There was no significant difference among groups in terms of the MB, HJ, VJ or BC results at any time point (P>0·05). SS in the KE exercise was significantly greater in the LI + BFR group compared to the CG group (P = 0·014) during the LP. Therefore, ST with BFR does not appear to improve the power of upper and lower limbs and may be an alternative to improve the SS of lower limbs of eumenorrheic women. © 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  13. Effects of caffeine intake on muscle strength and power: a systematic review and meta-analysis.

    PubMed

    Grgic, Jozo; Trexler, Eric T; Lazinica, Bruno; Pedisic, Zeljko

    2018-01-01

    Caffeine is commonly used as an ergogenic aid. Literature about the effects of caffeine ingestion on muscle strength and power is equivocal. The aim of this systematic review and meta-analysis was to summarize results from individual studies on the effects of caffeine intake on muscle strength and power. A search through eight databases was performed to find studies on the effects of caffeine on: (i) maximal muscle strength measured using 1 repetition maximum tests; and (ii) muscle power assessed by tests of vertical jump. Meta-analyses of standardized mean differences (SMD) between placebo and caffeine trials from individual studies were conducted using the random effects model. Ten studies on the strength outcome and ten studies on the power outcome met the inclusion criteria for the meta-analyses. Caffeine ingestion improved both strength (SMD = 0.20; 95% confidence interval [CI]: 0.03, 0.36; p  = 0.023) and power (SMD = 0.17; 95% CI: 0.00, 0.34; p  = 0.047). A subgroup analysis indicated that caffeine significantly improves upper (SMD = 0.21; 95% CI: 0.02, 0.39; p  = 0.026) but not lower body strength (SMD = 0.15; 95% CI: -0.05, 0.34; p  = 0.147). The meta-analyses showed significant ergogenic effects of caffeine ingestion on maximal muscle strength of upper body and muscle power. Future studies should more rigorously control the effectiveness of blinding. Due to the paucity of evidence, additional findings are needed in the female population and using different forms of caffeine, such as gum and gel.

  14. Decreased neck muscle strength in patients with the loss of cervical lordosis.

    PubMed

    Alpayci, Mahmut; Şenköy, Emre; Delen, Veysel; Şah, Volkan; Yazmalar, Levent; Erden, Metin; Toprak, Murat; Kaplan, Şeyhmus

    2016-03-01

    The loss of cervical lordosis is associated with some negative clinical outcomes. No previous study has examined cervical muscle strength, specifically in patients with the loss of cervical lordosis. This study aims to investigate whether there is weakness of the cervical muscles or an imbalance between cervical flexor and extensor muscle strength in patients with the loss of cervical lordosis compared with healthy controls matched by age, gender, body mass index (BMI), and employment status. Thirty-two patients with the loss of cervical lordosis (23 F, 9 M) and 31 healthy volunteers (23 F, 8 M) were included in the study. Maximal isometric neck extension and flexion strength, and the strength ratio between extension and flexion were used as evaluation parameters. All measurements were conducted by a blinded assessor using a digital force gauge. The participants were positioned on a chair in a neutral cervical position and without the trunk inclined during measurements. Maximal isometric neck extension and flexion strength values were significantly lower in the patients versus healthy controls (P<0.001 and P=0.040, respectively). The mean (SD) values of the extension/flexion ratio were 1.21 (0.34) in the patients and 1.46 ± 0.33 in the controls (P=0.004). According to our results, patients with the loss of cervical lordosis have reduced neck muscle strength, especially in the extensors. These findings may be beneficial for optimizing cervical exercise prescriptions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Does grip strength reflect isokinetic muscle strength in lower limbs in patients with chronic inflammatory demyelinating polyneuropathy?

    PubMed

    Knak, Kirsten L; Andersen, Linda K; Christiansen, Ingelise; Markvardsen, Lars K

    2018-03-30

    Grip strength (GS) is a common measure of general muscle strength in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). However, it is important to investigate the correlation and responsiveness of GS compared with isokinetic muscle strength (IKS) and function of the lower limbs. Seventy patients with CIDP were evaluated with GS, IKS, and functional measures of the lower limbs. Reevaluation was performed after 2 and 10/12 weeks. Correlation and response analyses were performed. GS correlated with IKS at the ankle (IKS ankle ; maximum Spearman's rank-order correlation [R S ] = 0.58) and with walking performance (maximum R S  = -0.38). IKS ankle was more responsive to detect change (standardized response mean [SRM] = 0.57) than GS (SRM = 0.27). GS does not seem to be an appropriate surrogate measure of IKS and function of the lower limbs in patients with CIDP. Muscle Nerve, 2018. © 2018 Wiley Periodicals, Inc.

  16. The role of trunk muscles in sitting balance control in people with low back pain.

    PubMed

    Freddolini, Marco; Strike, Siobhan; Lee, Raymond Y W

    2014-12-01

    The purpose of this study was to examine the muscular activities and kinetics of the trunk during unstable sitting in healthy and LBP subjects. Thirty-one healthy subjects and twenty-three LBP subjects were recruited. They were sat on a custom-made chair mounted on a force plate. Each subject was asked to regain balance after the chair was tilted backward at 20°, and then released. The motions of the trunk and trunk muscle activity were examined. The internal muscle moment and power at the hip and lumbar spine joints were calculated using the force plate and motion data. No significant differences were found in muscle moment and power between healthy and LBP subjects (p>0.05). The duration of contraction of various trunk muscles and co-contraction were significantly longer in the LBP subjects (p<0.05) when compared to healthy subjects, and the reaction times of the muscles were also significantly reduced in LBP subjects (p<0.05). LBP subjects altered their muscle strategies to maintain balance during unstable sitting, but these active mechanisms appear to be effective as trunk balance was not compromised and the internal moment pattern remained similar. The changes in muscle strategies may be the causes of LBP or the result of LBP with an attempt to protect the spine. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Bone strength and muscle properties in postmenopausal women with and without a recent distal radius fracture.

    PubMed

    Crockett, K; Arnold, C M; Farthing, J P; Chilibeck, P D; Johnston, J D; Bath, B; Baxter-Jones, A D G; Kontulainen, S A

    2015-10-01

    Distal radius (wrist) fracture (DRF) in women over age 50 years is an early sign of bone fragility. Women with a recent DRF compared to women without DRF demonstrated lower bone strength, muscle density, and strength, but no difference in dual-energy x-ray absorptiometry (DXA) measures, suggesting DXA alone may not be a sufficient predictor for DRF risk. The objective of this study was to investigate differences in bone and muscle properties between women with and without a recent DRF. One hundred sixty-six postmenopausal women (50-78 years) were recruited. Participants were excluded if they had taken bone-altering medications in the past 6 months or had medical conditions that severely affected daily living or the upper extremity. Seventy-seven age-matched women with a fracture in the past 6-24 months (Fx, n = 32) and without fracture (NFx, n = 45) were measured for bone and muscle properties using the nondominant (NFx) or non-fractured limb (Fx). Peripheral quantitative computed tomography (pQCT) was used to estimate bone strength in compression (BSIc) at the distal radius and tibia, bone strength in torsion (SSIp) at the shaft sites, muscle density, and area at the forearm and lower leg. Areal bone mineral density at the ultradistal forearm, spine, and femoral neck was measured by DXA. Grip strength and the 30-s chair stand test were used as estimates of upper and lower extremity muscle strength. Limb-specific between-group differences were compared using multivariate analysis of variance (MANOVA). There was a significant group difference (p < 0.05) for the forearm and lower leg, with the Fx group demonstrating 16 and 19% lower BSIc, 3 and 6% lower muscle density, and 20 and 21% lower muscle strength at the upper and lower extremities, respectively. There were no differences between groups for DXA measures. Women with recent DRF had lower pQCT-derived estimated bone strength at the distal radius and tibia and lower muscle density and strength at both extremities.

  18. Effect of armor and carrying load on body balance and leg muscle function.

    PubMed

    Park, Huiju; Branson, Donna; Kim, Seonyoung; Warren, Aric; Jacobson, Bert; Petrova, Adriana; Peksoz, Semra; Kamenidis, Panagiotis

    2014-01-01

    This study investigated the impact of weight and weight distribution of body armor and load carriage on static body balance and leg muscle function. A series of human performance tests were conducted with seven male, healthy, right-handed military students in seven garment conditions with varying weight and weight distributions. Static body balance was assessed by analyzing the trajectory of center of plantar pressure and symmetry of weight bearing in the feet. Leg muscle functions were assessed by analyzing the peak electromyography amplitude of four selected leg muscles during walking. Results of this study showed that uneven weight distribution of garment and load beyond an additional 9 kg impaired static body balance as evidenced by increased sway of center of plantar pressure and asymmetry of weight bearing in the feet. Added weight on non-dominant side of the body created greater impediment to static balance. Increased garment weight also elevated peak EMG amplitude in the rectus femoris to maintain body balance and in the medial gastrocnemius to increase propulsive force. Negative impacts on balance and leg muscle function with increased carrying loads, particularly with an uneven weight distribution, should be stressed to soldiers, designers, and sports enthusiasts. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Muscle strength and physical performance as predictors of mortality, hospitalization, and disability in the oldest old.

    PubMed

    Legrand, Delphine; Vaes, Bert; Matheï, Catharina; Adriaensen, Wim; Van Pottelbergh, Gijs; Degryse, Jean-Marie

    2014-06-01

    To evaluate the predictive value of muscle strength and physical performance in the oldest old for all-cause mortality; hospitalization; and the onset of disability, defined as a decline in activities of daily living (ADLs), independent of muscle mass, inflammatory markers, and comorbidities. A prospective, observational, population-based follow-up study. Three well-circumscribed areas of Belgium. Five hundred sixty participants aged 80 and older were followed for 33.5 months (interquartile range 31.1-35.6 months). Grip strength, Short Physical Performance Battery (SPPB) score, and muscle mass were measured at baseline; ADLs at baseline and after 20 months; and all-cause mortality and time to first hospitalization from inclusion onward. Kaplan-Meier curves and Cox proportional hazards models were calculated for all-cause mortality and hospitalization. Logistic regression analysis was used to determine predictors of decline in ADLs. Kaplan-Meier curves showed significantly higher all-cause mortality and hospitalization in subjects in the lowest tertile of grip strength and SPPB score. The adjusted Cox proportional hazards model showed that participants with high grip strength or a high SPPB score had a lower risk of mortality and hospitalization, independent of muscle mass, inflammatory markers, and comorbidity. A relationship was found between SPPB score and decline in ADLs, independent of muscle mass, inflammation, and comorbidity. In people aged 80 and older, physical performance is a strong predictor of mortality, hospitalization, and disability, and muscle strength is a strong predictor of mortality and hospitalization. All of these relationships were independent of muscle mass, inflammatory markers, and comorbidity. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

  20. The impact of type 1 diabetes and diabetic polyneuropathy on muscle strength and fatigability.

    PubMed

    Orlando, Giorgio; Balducci, Stefano; Bazzucchi, Ilenia; Pugliese, Giuseppe; Sacchetti, Massimo

    2017-06-01

    Although it is widely accepted that diabetic polyneuropathy (DPN) is linked to a marked decline in neuromuscular performance, information on the possible impact of type 1 diabetes (T1D) on muscle strength and fatigue remains unclear. The purpose of this study was to investigate the effects of T1D and DPN on strength and fatigability in knee extensor muscles. Thirty-one T1D patients (T1D), 22 T1D patients with DPN (DPN) and 23 matched healthy control participants (C) were enrolled. Maximal voluntary contraction (MVC) and endurance time at an intensity level of 50% of the MVC were assessed at the knee extensor muscles with an isometric dynamometer. Clinical characteristics of diabetic patients were assessed by considering a wide range of vascular and neurological parameters. DPN group had lower knee extensor muscles strength than T1D (-19%) and the C group (-37.5%). T1D group was 22% weaker when compared to the C group. Lower body muscle fatigability of DPN group was 22 and 45.5% higher than T1D and C group, respectively. T1D group possessed a higher fatigability (29.4%) compared to C group. A correlation was found between motor and sensory nerve conduction velocity and muscle strength and fatigability. Patients with T1D are characterised by both a higher fatigability and a lower muscle strength, which are aggravated by DPN. Our data suggest that factors other than nervous damage play a role in the pathogenesis of such defect.

  1. Joint proprioception, muscle strength, and functional ability in patients with osteoarthritis of the knee.

    PubMed

    van der Esch, M; Steultjens, M; Harlaar, J; Knol, D; Lems, W; Dekker, J

    2007-06-15

    To test the hypotheses that poor knee joint proprioception is related to limitations in functional ability, and poor proprioception aggravates the impact of muscle weakness on limitations in functional ability in osteoarthritis (OA) of the knee. Sixty-three patients with symptomatic OA of the knee were tested. Proprioceptive acuity was assessed by establishing the joint motion detection threshold (JMDT) in the anteroposterior direction. Muscle strength was measured using a computer-driven isokinetic dynamometer. Functional ability was assessed by the 100-meter walking test, the Get Up and Go (GUG) test, and the Western Ontario and McMaster Universities Osteoarthritis Index physical function (WOMAC-PF) questionnaire. Correlation analyses were performed to assess the relationship between proprioception, muscle strength, and functional ability. Regression analyses were performed to assess the impact of proprioception on the relationship between muscle strength and functional ability. Poor proprioception (high JMDT) was related to more limitation in functional ability (walking time r = 0.30, P < 0.05; GUG time r = 0.30, P < 0.05; WOMAC-PF r = 0.26, P <0.05). In regression analyses, the interaction between proprioception and muscle strength was significantly related to functional ability (walking time, P < 0.001 and GUG time, P < 0.001) but not to WOMAC-PF score (P = 0.625). In patients with poor proprioception, reduction of muscle strength was associated with more severe deterioration of functional ability than in patients with accurate proprioception. Patients with poor proprioception show more limitation in functional ability, but this relationship is rather weak. In patients with poor proprioception, muscle weakness has a stronger impact on limitations in functional ability than in patients with accurate proprioception.

  2. Strategies for Optimizing Strength, Power, and Muscle Hypertrophy in Women.

    DTIC Science & Technology

    1997-09-01

    the injury risks and inefficiencies of other methods for the more sophisticated assessment of human muscular strength and power. To provide...an environment of total safety. Limiting catches prevent injury through falling or loss of control of the loaded bar and a specially designed...J., Rodman, K.W., and Sebolt, D.R. The effect of endurance running on training adaptations in women participating in a weightlifting program. J

  3. Effects of high-intensity interval cycling performed after resistance training on muscle strength and hypertrophy.

    PubMed

    Tsitkanou, S; Spengos, K; Stasinaki, A-N; Zaras, N; Bogdanis, G; Papadimas, G; Terzis, G

    2017-11-01

    Aim of the study was to investigate whether high-intensity interval cycling performed immediately after resistance training would inhibit muscle strength increase and hypertrophy expected from resistance training per se. Twenty-two young men were assigned into either resistance training (RE; N = 11) or resistance training plus high-intensity interval cycling (REC; N = 11). Lower body muscle strength and rate of force development (RFD), quadriceps cross-sectional area (CSA) and vastus lateralis muscle architecture, muscle fiber type composition and capillarization, and estimated aerobic capacity were evaluated before and after 8 weeks of training (2 times per week). Muscle strength and quadriceps CSA were significantly and similarly increased after both interventions. Fiber CSA increased significantly and similarly after both RE (type I: 13.6 ± 3.7%, type IIA: 17.6 ± 4.4%, type IIX: 23.2 ± 5.7%, P < 0.05) and REC (type I: 10.0 ± 2.7%, type IIA: 14.8 ± 4.3% type IIX: 20.8 ± 6.0%, P < 0.05). In contrast, RFD decreased and fascicle angle increased (P < 0.05) only after REC. Capillary density and estimated aerobic capacity increased (P < 0.05) only after REC. These results suggest that high-intensity interval cycling performed after heavy-resistance exercise may not inhibit resistance exercise-induced muscle strength/hypertrophy after 2 months of training, while it prompts aerobic capacity and muscle capillarization. The addition of high-intensity cycling after heavy-resistance exercise may decrease RFD partly due to muscle architectural changes. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Self-Managed Exercises, Fitness and Strength Training, and Multifidus Muscle Size in Elite Footballers.

    PubMed

    Hides, Julie A; Walsh, Jazmin C; Smith, Melinda M Franettovich; Mendis, M Dilani

    2017-07-01

      Low back pain (LBP) and lower limb injuries are common among Australian Football League (AFL) players. Smaller size of 1 key trunk muscle, the lumbar multifidus (MF), has been associated with LBP and injuries in footballers. The size of the MF muscle has been shown to be modifiable with supervised motor-control training programs. Among AFL players, supervised motor-control training has also been shown to reduce the incidence of lower limb injuries and was associated with increased player availability for games. However, the effectiveness of a self-managed MF exercise program is unknown.   To investigate the effect of self-managed exercises and fitness and strength training on MF muscle size in AFL players with or without current LBP.   Cross-sectional study.   Professional AFL context.   Complete data were available for 242 players from 6 elite AFL clubs.   Information related to the presence of LBP and history of injury was collected at the start of the preseason. At the end of the preseason, data were collected regarding performance of MF exercises as well as fitness and strength training. Ultrasound imaging of the MF muscle was conducted at the start and end of the preseason.   Size of the MF muscles.   An interaction effect was found between performance of MF exercises and time (F = 13.89, P ≤ .001). Retention of MF muscle size was greatest in players who practiced the MF exercises during the preseason (F = 4.77, P = .03). Increased adherence to fitness and strength training was associated with retained MF muscle size over the preseason (F = 5.35, P = .02).   Increased adherence to a self-administered MF exercise program and to fitness and strength training was effective in maintaining the size of the MF muscle in the preseason.

  5. Effects of 1 week of unilateral ankle immobilization on plantar-flexor strength, balance, and walking speed: a pilot study in asymptomatic volunteers.

    PubMed

    Caplan, Nick; Forbes, Andrew; Radha, Sarkhell; Stewart, Su; Ewen, Alistair; St Clair Gibson, Alan; Kader, Deiary

    2015-05-01

    Ankle immobilization is often used after ankle injury. To determine the influence of 1 week's unilateral ankle immobilization on plantar-flexor strength, balance, and walking gait in asymptomatic volunteers. Repeated-measures laboratory study. University laboratory. 6 physically active male participants with no recent history of lower-limb injury. Participants completed a 1-wk period of ankle immobilization achieved through wearing a below-knee ankle cast. Before the cast was applied, as well as immediately, 24 h, and 48 h after cast removal, their plantar-flexor strength was assessed isokinetically, and they completed a single-leg balance task as a measure of proprioceptive function. An analysis of their walking gait was also completed Main Outcome Measures: Peak plantar-flexor torque and balance were used to determine any effect on muscle strength and proprioception after cast removal. Ranges of motion (3D) of the ankle, knee, and hip, as well as walking speed, were used to assess any influence on walking gait. After cast removal, plantar-flexor strength was reduced for the majority of participants (P = .063, CI = -33.98 to 1.31) and balance performance was reduced in the immobilized limb (P < .05, CI = 0.84-5.16). Both strength and balance were not significantly different from baseline levels by 48 h. Walking speed was not significantly different immediately after cast removal but increased progressively above baseline walking speed over the following 48 h. Joint ranges of motion were not significantly different at any time point. The reduction in strength and balance after such a short period of immobilization suggested compromised central and peripheral neural mechanisms. This suggestion appeared consistent with the delayed increase in walking speed that could occur as a result of the excitability of the neural pathways increasing toward baseline levels.

  6. Dynamics of muscle strength improvement during isokinetic rehabilitation of athletes with ACL rupture and chondromalacia patellae.

    PubMed

    Desnica Bakrac, N

    2003-03-01

    To assess quantitatively dynamics and extent of the increase in muscle strength during isokinetic rehabilitation. daily measurements of muscle strength; detailed testing at the beginning and at the end of rehabilitation. Cybex Rehabilitation Center, Zagreb. 44 athletes (31 m, 13 F, age 16-35), 3 injury-defined groups: athletes with ACL rupture (non-reconstructed and reconstructed) and chondromalacia patellae. all subjects underwent isokinetic rehabilitation on Cybex Orthotron KT2 device, using individually designed protocols (extension and flexion exercises, concentric muscle contractions, 15 treatments). monitoring of daily progress on rehabilitation device and detailed testing on diagnostic device. All patients showed considerable improvement. Muscle strength improved on average 141% (SD=110) in ACL-reconstructed group, 144% (SD=130) for chondromalacia patellae group and 150% (SD=74) for ACL-non-reconstructed group, comparing to initial strength. Dynamic status tested on Cybex Otrhotron diagnostic device prior and after rehabilitation strongly correlated with final progress monitored on the rehabilitation device. Isokinetic rehabilitation is a quick and effective method in treating knee injuries in athletes. Both types of objective criteria have shown significant increase in muscle strength. The improvement of muscle strength was on the average 149% (SD=101), which is about 10% daily for 15 treatments. The greatest progress, 19% per day, occurred during first five days. The athletes were able to resume their sport activities as follows: patients from chondromalacia patellae group, and most of them from the non-reconstructed ACL group were back in competition within a month, while 75% from the ACL reconstructed group came back within 3 months, and the rest of them within 5 months.

  7. Bone geometry, strength, and muscle size in runners with a history of stress fracture.

    PubMed

    Popp, Kristin L; Hughes, Julie M; Smock, Amanda J; Novotny, Susan A; Stovitz, Steven D; Koehler, Scott M; Petit, Moira A

    2009-12-01

    Our primary aim was to explore differences in estimates of tibial bone strength, in female runners with and without a history of stress fractures. Our secondary aim was to explore differences in bone geometry, volumetric density, and muscle size that may explain bone strength outcomes. A total of 39 competitive distance runners aged 18-35 yr, with (SFX, n = 19) or without (NSFX, n = 20) a history of stress fracture were recruited for this cross-sectional study. Peripheral quantitative computed tomography (XCT 3000; Orthometrix, White Plains, NY) was used to assess volumetric bone mineral density (vBMD, mg x mm(-3)), bone area (ToA, mm(2)), and estimated compressive bone strength (bone strength index (BSI) = ToA x total volumetric density (ToD(2))) at the distal tibia (4%). Total (ToA, mm(2)) and cortical (CoA, mm(2)) bone area, cortical vBMD, and estimated bending strength (strength-strain index (SSIp), mm(3)) were measured at the 15%, 25%, 33%, 45%, 50%, and 66% sites. Muscle cross-sectional area (MCSA) was measured at the 50% and 66% sites. Participants in the SFX group had significantly smaller (7%-8%) CoA at the 45%, 50%, and 66% sites (P strength, cortical area, and MCSA are all lower in runners with a history of stress fracture. However, the lower strength was appropriate for the smaller muscle size, suggesting that interventions to reduce stress fracture risk might be aimed at improving muscle size and strength.

  8. Effect of a Hippotherapy Intervention Program on Static Balance and Strength in Adolescents with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Giagazoglou, Paraskevi; Arabatzi, Fotini; Dipla, Konstantina; Liga, Maria; Kellis, Eleftherios

    2012-01-01

    The aim of this study was to assess the effects of a hippotherapy program on static balance and strength in adolescents with intellectual disability (ID). Nineteen adolescents with moderate ID were assigned either an experimental group (n = 10) or a control group (n = 9). The experimental group attended a 10-week hippotherapy program. To assess…

  9. Effects of Balance Training on Postural Sway, Leg Extensor Strength, and Jumping Height in Adolescents

    ERIC Educational Resources Information Center

    Granacher, Urs; Gollhofer, Albert; Kriemler, Susi

    2010-01-01

    Deficits in strength of the lower extremities and postural control have been associated with a high risk of sustaining sport-related injuries. Such injuries often occur during physical education (PE) classes and mostly affect the lower extremities. Thus, the objectives of this study were to investigate the effects of balance training on postural…

  10. Impaired muscle strength may contribute to fatigue in patients with aneurysmal subarachnoid hemorrhage.

    PubMed

    Harmsen, Wouter J; Ribbers, Gerard M; Zegers, Bart; Sneekes, Emiel M; Praet, Stephan F E; Heijenbrok-Kal, Majanka H; Khajeh, Ladbon; van Kooten, Fop; Neggers, Sebastiaan J C M M; van den Berg-Emons, Rita J

    2017-03-01

    Patients with aneurysmal subarachnoid hemorrhage (a-SAH) show long-term fatigue and face difficulties in resuming daily physical activities. Impaired muscle strength, especially of the lower extremity, impacts the performance of daily activities and may trigger the onset of fatigue complaints. The present study evaluated knee muscle strength and fatigue in patients with a-SAH. This study included 33 patients, 6 months after a-SAH, and 33 sex-matched and age-matched healthy controls. Isokinetic muscle strength of the knee extensors and flexors was measured at 60 and 180°/s. Maximal voluntary muscle strength was defined as peak torque and measured in Newton-meter. Fatigue was examined using the Fatigue Severity Scale. In patients with a-SAH, the maximal knee extension was 22% (60°/s) and 25% (180°/s) lower and maximal knee flexion was 33% (60°/s) and 36% (180°/s) lower compared with that of matched controls (P≤0.001). The Fatigue Severity Scale score was related to maximal knee extension (60°/s: r=-0.426, P=0.015; 180°/s: r=-0.376, P=0.034) and flexion (60°/s: r=-0.482, P=0.005; 180°/s: r=-0.344, P=0.083). The knee muscle strength was 28-47% lower in fatigued (n=13) and 11-32% lower in nonfatigued (n=20) patients; deficits were larger in fatigued patients (P<0.05), particularly when the muscle strength (peak torque) was measured at 60°/s. The present results indicate that patients with a-SAH have considerably impaired knee muscle strength, which is related to more severe fatigue. The present findings are exploratory, but showed that knee muscle strength may play a role in the severity of fatigue complaints, or vice versa. Interventions targeting fatigue after a-SAH seem necessary and may consider strengthening exercise training in order to treat a debilitating condition.

  11. Shoulder muscle strength in paraplegics before and after kayak ergometer training.

    PubMed

    Bjerkefors, Anna; Jansson, Anna; Thorstensson, Alf

    2006-07-01

    The purpose was to investigate if shoulder muscle strength in post-rehabilitated persons with spinal cord injury (SCI) was affected by kayak ergometer training and to compare shoulder strength in persons with SCI and able-bodied persons. Ten persons with SCI (7 males and 3 females, injury levels T3-T12) performed 60 min kayak ergometer training three times a week for 10 weeks with progressively increased intensity. Maximal voluntary concentric contractions were performed during six shoulder movements: flexion and extension (range of motion 65 degrees ), abduction and adduction (65 degrees ), and external and internal rotation (60 degrees ), with an angular velocity of 30 degrees s(-1). Position specific strength was assessed at three shoulder angles (at the beginning, middle and end of the range of motion) in the respective movements. Test-retests were performed for all measurements before the training and the mean intraclass correlation coefficient was 0.941 (95% CI 0.928-0.954). There was a main effect of kayak ergometer training with increased shoulder muscle strength after training in persons with SCI. The improvements were independent of shoulder movement, and occurred in the beginning and middle positions. A tendency towards lower shoulder muscle strength was observed in the SCI group compared to a matched reference group of able-bodied persons. Thus, it appears that post-rehabilitated persons with SCI have not managed to fully regain/maintain their shoulder muscle strength on a similar level as that of able-bodied persons, and are able to improve their shoulder muscle strength after a period of kayak ergometer training.

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

    PubMed

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

    2004-09-01

    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. 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. 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. 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.

  13. Decreased Respiratory Muscle Function Is Associated with Impaired Trunk Balance among Chronic Stroke Patients: A Cross-sectional Study.

    PubMed

    Lee, Kyeongbong; Cho, Ji-Eun; Hwang, Dal-Yeon; Lee, WanHee

    2018-06-01

    The abdominal muscles play a role in trunk balance. Abdominal muscle thickness is asymmetrical in stroke survivors, who also have decreased respiratory muscle function. We compared the thickness of the abdominal muscles between the affected and less affected sides in stroke survivors. In addition, the relationship between respiratory muscle function and trunk balance was evaluated. Chronic stroke patients (18 men, 15 women; mean age, 58.94 ± 12.30 years; Mini-Mental Status Examination score ≥ 24) who could sit without assist were enrolled. Abdominal muscle thickness during rest and contraction was measured with ultrasonography, and the thickening ratio was calculated. Respiratory muscle function assessment included maximum respiratory pressure, peak flow, and air volume. Trunk function was evaluated using the Trunk Impairment Scale, and trunk balance was estimated based on the center of pressure velocity and path length within the limit of stability in sitting posture. Abdominal muscles were significantly thinner on the affected side, and the thickening ratio was lower in the affected side (P < 0.05). In addition, the higher thickening ratio of the affected side showed significant relationship with higher trunk function. Moreover, higher respiratory muscle function was significantly correlated with higher level of trunk function and balance in stroke patients (P < 0.05). Thus, chronic stroke survivors have decreased abdominal muscle thickness on the affected side, and respiratory muscle function has positive correlation with trunk function and balance. We propose that respiratory muscle training should be included as part of trunk balance training in chronic stroke patients.

  14. Cardiopulmonary fitness and muscle strength in patients with osteogenesis imperfecta type I.

    PubMed

    Takken, Tim; Terlingen, Heike C; Helders, Paul J M; Pruijs, Hans; Van der Ent, Cornelis K; Engelbert, Raoul H H

    2004-12-01

    To evaluate cardiopulmonary function, muscle strength, and cardiopulmonary fitness (VO 2 peak) in patients with osteogenesis imperfecta (OI). In 17 patients with OI type I (mean age 13.3 +/- 3.9 years) cardiopulmonary function was assessed at rest using spirometry, plethysmography, electrocardiography, and echocardiography. Exercise capacity was measured using a maximal exercise test on a bicycle ergometer and an expired gas analysis system. Muscle strength in shoulder abductors, hip flexors, ankle dorsal flexor, and grip strength were measured. All results were compared with reference values. Cardiopulmonary function at rest was within normal ranges, but when it was compared with normal height for age and sex, vital capacities were reduced. Mean absolute and relative VO 2 peak were respectively -1.17 (+/- 0.67) and -1.41 (+/- 1.52) standard deviations lower compared with reference values ( P < .01). Muscle strength also was significantly reduced in patients with OI, ranging from -1.24 +/- 1.40 to -2.88 +/- 2.67 standard deviations lower compared with reference values. In patients with OI type I, no pulmonary or cardiac abnormalities at rest were found. The exercise tolerance and muscle strength were significantly reduced in patients with OI, which might account for their increased levels of fatigue during activities of daily living.

  15. A Maximum Muscle Strength Prediction Formula Using Theoretical Grade 3 Muscle Strength Value in Daniels et al.'s Manual Muscle Test, in Consideration of Age: An Investigation of Hip and Knee Joint Flexion and Extension.

    PubMed

    Usa, Hideyuki; Matsumura, Masashi; Ichikawa, Kazuna; Takei, Hitoshi

    2017-01-01

    This study attempted to develop a formula for predicting maximum muscle strength value for young, middle-aged, and elderly adults using theoretical Grade 3 muscle strength value (moment fair: M f )-the static muscular moment to support a limb segment against gravity-from the manual muscle test by Daniels et al. A total of 130 healthy Japanese individuals divided by age group performed isometric muscle contractions at maximum effort for various movements of hip joint flexion and extension and knee joint flexion and extension, and the accompanying resisting force was measured and maximum muscle strength value (moment max, M m ) was calculated. Body weight and limb segment length (thigh and lower leg length) were measured, and M f was calculated using anthropometric measures and theoretical calculation. There was a linear correlation between M f and M m in each of the four movement types in all groups, excepting knee flexion in elderly. However, the formula for predicting maximum muscle strength was not sufficiently compatible in middle-aged and elderly adults, suggesting that the formula obtained in this study is applicable in young adults only.

  16. A Maximum Muscle Strength Prediction Formula Using Theoretical Grade 3 Muscle Strength Value in Daniels et al.'s Manual Muscle Test, in Consideration of Age: An Investigation of Hip and Knee Joint Flexion and Extension

    PubMed Central

    Matsumura, Masashi; Ichikawa, Kazuna; Takei, Hitoshi

    2017-01-01

    This study attempted to develop a formula for predicting maximum muscle strength value for young, middle-aged, and elderly adults using theoretical Grade 3 muscle strength value (moment fair: Mf)—the static muscular moment to support a limb segment against gravity—from the manual muscle test by Daniels et al. A total of 130 healthy Japanese individuals divided by age group performed isometric muscle contractions at maximum effort for various movements of hip joint flexion and extension and knee joint flexion and extension, and the accompanying resisting force was measured and maximum muscle strength value (moment max, Mm) was calculated. Body weight and limb segment length (thigh and lower leg length) were measured, and Mf was calculated using anthropometric measures and theoretical calculation. There was a linear correlation between Mf and Mm in each of the four movement types in all groups, excepting knee flexion in elderly. However, the formula for predicting maximum muscle strength was not sufficiently compatible in middle-aged and elderly adults, suggesting that the formula obtained in this study is applicable in young adults only. PMID:28133549

  17. Adaptive strength gains in dystrophic muscle exposed to repeated bouts of eccentric contraction

    PubMed Central

    Call, Jarrod A.; Eckhoff, Michael D.; Baltgalvis, Kristen A.; Warren, Gordon L.

    2011-01-01

    The objective of this study was to determine the functional recovery and adaptation of dystrophic muscle to multiple bouts of contraction-induced injury. Because lengthening (i.e., eccentric) contractions are extremely injurious for dystrophic muscle, it was considered that repeated bouts of such contractions would exacerbate the disease phenotype in mdx mice. Anterior crural muscles (tibialis anterior and extensor digitorum longus) and posterior crural muscles (gastrocnemius, soleus, and plantaris) from mdx mice performed one or five repeated bouts of 100 electrically stimulated eccentric contractions in vivo, and each bout was separated by 10–18 days. Functional recovery from one bout was achieved 7 days after injury, which was in contrast to a group of wild-type mice, which still showed a 25% decrement in electrically stimulated isometric torque at that time point. Across bouts there was no difference in the immediate loss of strength after repeated bouts of eccentric contractions for mdx mice (−70%, P = 0.68). However, after recovery from each bout, dystrophic muscle had greater torque-generating capacity such that isometric torque was increased ∼38% for both anterior and posterior crural muscles at bout 5 compared with bout 1 (P < 0.001). Moreover, isolated extensor digitorum longus muscles excised from in vivo-tested hindlimbs 14–18 days after bout 5 had greater specific force than contralateral control muscles (12.2 vs. 10.4 N/cm2, P = 0.005) and a 20% greater maximal relaxation rate (P = 0.049). Additional adaptations due to the multiple bouts of eccentric contractions included rapid recovery and/or sparing of contractile proteins, enhanced parvalbumin expression, and a decrease in fiber size variability. In conclusion, eccentric contractions are injurious to dystrophic skeletal muscle; however, the muscle recovers function rapidly and adapts to repeated bouts of eccentric contractions by improving strength. PMID:21960659

  18. Ischemic conditioning increases strength and volitional activation of paretic muscle in chronic stroke: a pilot study.

    PubMed

    Hyngstrom, Allison S; Murphy, Spencer A; Nguyen, Jennifer; Schmit, Brian D; Negro, Francesco; Gutterman, David D; Durand, Matthew J

    2018-05-01

    Ischemic conditioning (IC) on the arm or leg has emerged as an intervention to improve strength and performance in healthy populations, but the effects on neurological populations are unknown. The purpose of this study was to quantify the effects of a single session of IC on knee extensor strength and muscle activation in chronic stroke survivors. Maximal knee extensor torque measurements and surface EMG were quantified in 10 chronic stroke survivors (>1 yr poststroke) with hemiparesis before and after a single session of IC or sham on the paretic leg. IC consisted of 5 min of compression with a proximal thigh cuff (inflation pressure = 225 mmHg for IC or 25 mmHg for sham) followed by 5 min of rest. This was repeated five times. Maximal knee extensor strength, EMG magnitude, and motor unit firing behavior were measured before and immediately after IC or sham. IC increased paretic leg strength by 10.6 ± 8.5 Nm, whereas no difference was observed in the sham group (change in sham = 1.3 ± 2.9 Nm, P = 0.001 IC vs. sham). IC-induced increases in strength were accompanied by a 31 ± 15% increase in the magnitude of muscle EMG during maximal contractions and a 5% decrease in motor unit recruitment thresholds during submaximal contractions. Individuals who had the most asymmetry in strength between their paretic and nonparetic legs had the largest increases in strength ( r 2  = 0.54). This study provides evidence that a single session of IC can increase strength through improved muscle activation in chronic stroke survivors. NEW & NOTEWORTHY Present rehabilitation strategies for chronic stroke survivors do not optimally activate paretic muscle, and this limits potential strength gains. Ischemic conditioning of a limb has emerged as an effective strategy to improve muscle performance in healthy individuals but has never been tested in neurological populations. In this study, we show that ischemic conditioning on the paretic leg of chronic stroke survivors

  19. The Relationship between Vitamin D and Muscle Size and Strength in Patients on Hemodialysis

    PubMed Central

    Gordon, Patricia L.; Sakkas, Giorgos K.; Doyle, Julie W.; Shubert, Tiffany; Johansen, Kirsten L.

    2007-01-01

    OBJECTIVE Vitamin D has various actions in skeletal muscle. The purpose of this study was to compare lower limb muscle size and strength in hemodialysis (HD) patients being treated with 1,25-dihydroxyvitamin D (calcitriol) or a 1,25-dihydroxyvitamin D analog (paricalcitol) to HD patients who were receiving none. DESIGN This was a retrospective cross-sectional study. SETTING Outpatient hemodialysis centers. PATIENTS HD patients receiving calcitriol or paricalcitol (active vitamin D) for control of secondary hyperparathyroidism (VitD, n = 49) were compared to HD patients who were not (n = 30). MAIN OUTCOME MEASURES Cross-sectional areas (CSA) of thigh and tibialis anterior muscles by magnetic resonance imaging (MRI), and three measures of strength; three-repetition maximum (3RM) for knee extension (isotonic), peak torque of knee extensors (isokinetic), and maximal voluntary contraction (MVC) of the ankle dorsiflexor muscles (isometric). RESULTS There were no differences in age, weight, dialysis vintage, or intact parathyroid hormone levels between the groups, although serum albumin was higher in the VitD group (p <0.05). Patients in the VitD group had larger thigh muscle CSA (p < 0.05) and were stronger across all strength measures (p< 0.05) after controlling for age and gender (ANCOVA). When all analyses were subsequently adjusted for serum albumin concentration, only the difference in 3RM knee extension strength lost significance. There were no significant differences in any measurements between patients who received calcitriol or paricalcitol. CONCLUSION Treatment with active vitamin D was associated with greater muscle size and strength in this cohort of HD patients. PMID:17971312

  20. Rejuvenation of the aged muscle stem cell population restores strength to injured aged muscles

    PubMed Central

    Cosgrove, Benjamin D.; Gilbert, Penney M.; Porpiglia, Ermelinda; Mourkioti, Foteini; Lee, Steven P.; Corbel, Stephane Y.; Llewellyn, Michael E.; Delp, Scott L.; Blau, Helen M.

    2014-01-01

    The aged suffer from progressive muscle weakness and regenerative failure. We demonstrate that muscle regeneration is impaired with aging due in part to a cell-autonomous functional decline in skeletal muscle stem cells (MuSCs). Two-thirds of aged MuSCs are intrinsically defective relative to young MuSCs, with reduced capacity to repair myofibers and repopulate the stem cell reservoir in vivo following transplantation due to a higher incidence of cells that express senescence markers and that have elevated p38α/β MAPK activity. We show that these limitations cannot be overcome by transplantation into the microenvironment of young recipient muscles. In contrast, subjecting the aged MuSC population to transient inhibition of p38α/β in conjunction with culture on soft hydrogel substrates rapidly expands the residual functional aged MuSC population, rejuvenating its potential for regeneration, serial transplantation, and strengthening damaged muscles of aged mice. These findings reveal a synergy between biophysical and biochemical cues that provides a paradigm for a localized autologous muscle stem cell therapy in aged individuals. PMID:24531378

  1. Effect of Expiratory Resistive Loading in Expiratory Muscle Strength Training on Orbicularis Oris Muscle Activity

    PubMed Central

    Yanagisawa, Yukio; Matsuo, Yoshimi; Shuntoh, Hisato; Horiuchi, Noriaki

    2014-01-01

    [Purpose] The purpose of this study was to elucidate the effect of expiratory resistive loading on orbicularis oris muscle activity. [Subjects] Subjects were 23 healthy individuals (11 males, mean age 25.5±4.3 years; 12 females, mean age 25.0±3.0 years). [Methods] Surface electromyography was performed to measure the activity of the orbicularis oris muscle during maximum lip closure and resistive loading at different expiratory pressures. Measurement was performed at 10%, 30%, 50%, and 100% of maximum expiratory pressure (MEP) for all subjects. The t-test was used to compare muscle activity between maximum lip closure and 100% MEP, and analysis of variance followed by multiple comparisons was used to compare the muscle activities observed at different expiratory pressures. [Results] No significant difference in muscle activity was observed between maximum lip closure and 100% MEP. Analysis of variance with multiple comparisons revealed significant differences among the different expiratory pressures. [Conclusion] Orbicularis oris muscle activity increased with increasing expiratory resistive loading. PMID:24648644

  2. Upper Extremity Muscle Volumes and Functional Strength After Resistance Training in Older Adults

    PubMed Central

    Daly, Melissa; Vidt, Meghan E.; Eggebeen, Joel D.; Simpson, W. Greg; Miller, Michael E.; Marsh, Anthony P.; Saul, Katherine R.

    2014-01-01

    Aging leads to a decline in strength and an associated loss of independence. The authors examined changes in muscle volume, maximum isometric joint moment, functional strength, and 1-repetition maximum (1RM) after resistance training (RT) in the upper extremity of older adults. They evaluated isometric joint moment and muscle volume as predictors of functional strength. Sixteen healthy older adults (average age 75 ± 4.3 yr) were randomized to a 6-wk upper extremity RT program or control group. The RT group increased 1RM significantly (p < .01 for all exercises). Compared with controls, randomization to RT led to greater functional pulling strength (p = .003), isometric shoulder-adduction moment (p = .041), elbow-flexor volume (p = .017), and shoulder-adductor volume (p = .009). Shoulder-muscle volumes and isometric moments were good predictors of functional strength. The authors conclude that shoulder strength is an important factor for performing functional reaching and pulling tasks and a key target for upper extremity RT interventions. PMID:22952203

  3. The Immediate Effect of Neuromuscular Joint Facilitation (NJF) Treatment on Hip Muscle Strength.

    PubMed

    Wang, Hongdan; Huo, Ming; Huang, Qiuchen; Li, Desheng; Maruyama, Hitoshi

    2013-11-01

    [Purpose] This study investigated the change in hip muscle strength of younger persons after neuromuscular joint facilitation (NJF) treatment. [Subjects] The subjects were 45 healthy young people, who were divided into two groups: a NJF group and a proprioceptive neuromuscular facilitation (PNF) group. The NJF group consisted of 21 subjects (11 males, 10 females), and the PNF group consisted of 24 subjects (11 males, 13 females). [Methods] Participants in the NJF group received NJF treatment. We measured the maximal flexor strength and the maximal extensor strength during isokinetic movement of the hip joint before and after intervention in both groups. The angular velocities used were 60°/sec and 180°/sec. [Results] The NJF group showed significant increases in the maximal flexor strength and the maximal extensor strength after the intervention at each angular velocity. In the PNF group, the maximal flexor strength of 60°/sec and the maximal extensor strength of 180°/sec were significant increases. [Conclusion] These results suggest that there is an immediate effect of NJF intervention on hip muscle strength.

  4. Comparison of Three Methods of Assessing Muscle Strength and Imbalance Ratios of the Knee

    PubMed Central

    Moss, Crayton L.; Wright, P. Thomas

    1993-01-01

    Three strength measurement methods for determining muscle strength and imbalance ratios of the knee were compared in 41 (23 female, 18 male) NCAA Division I track and field athletes. Peak quadriceps extensions and hamstring flexions were measured isotonically, isometrically, and isokinetically. Isokinetic measurements were performed on a Cybex II at 60°/s. Isometric extension and flexion measurements were performed using the Nicholas Manual Muscle Tester (Lafayette Instruments; Lafayette, Ind). Isotonic measurements were done on both Universal and Nautilus apparatuses. Testing order was randomized to avoid a treatment order effect. A repeated measures ANOVA and a post hoc Tukey test were used to compare the three methods of assessing strength and imbalance ratios of the knee. Absolute strength values were significantly different according to gender and mode of testing. Bilateral strength imbalance ratios for knee flexion were significantly lower for the Nautilus leg curl machine. Ipsilateral strength imbalance ratios were significantly greater for the Cybex II. Our results indicated that absolute strength values cannot be interchanged between testing modes. Except for Cybex II (ipsilateral) and Nautilus (bilateral knee flexion), strength imbalance ratios could be interchanged. ImagesFig 1.Fig 2.Fig 3.Fig 4.Fig 5.Fig 6.Fig 7.INGING PMID:16558207

  5. Normative Quadriceps and Hamstring Muscle Strength Values for Female, Healthy, Elite Handball and Football Players.

    PubMed

    Risberg, May A; Steffen, Kathrin; Nilstad, Agnethe; Myklebust, Grethe; Kristianslund, Eirik; Moltubakk, Marie M; Krosshaug, Tron

    2018-05-23

    Risberg, MA, Steffen, K, Nilstad, A, Myklebust, G, Kristianslund, E, Moltubakk, MM, and Krosshaug, T. Normative quadriceps and hamstring muscle strength values for female, healthy, elite handball and football players. J Strength Cond Res XX(X): 000-000, 2018-This study presents normative values for isokinetic knee extension and flexion muscle strength tests in 350 elite, female, handball (n = 150) and football (n = 200) players. Isokinetic concentric muscle strength tests at 60°·sec were recorded bilaterally using a dynamometer. Peak torque (in Newton meter [N·m]), body mass normalized peak torque (N·m·kg), and hamstring to quadriceps ratio (H:Q ratio) for dominant and nondominant legs were recorded. The female elite players were 20.9 ± 4.0 years, started playing at the elite level at the age of 18.2 ± 2.7 years, with a mean of 9.7 ± 2.2 hours of weekly in-season training. Handball players demonstrated greater quadriceps muscle strength compared with football players (11.0%) (p < 0.001), also when normalized to body mass (4.1%) (p = 0.012), but not for weight-adjusted hamstring muscle strength. The H:Q ratio was higher on the dominant compared with the nondominant leg for handball players only (p = 0.012).The H:Q ratio was significantly lower for handball players (0.58) compared with football players (0.60) (p < 0.02). These normative values for isokinetic knee extension and flexion torques of healthy, elite, female handball and football players can be used to set rehabilitation goals for muscle strength after injury and enable comparison with uninjured legs. Significantly greater quadriceps muscle strength was found for handball players compared with football players, also when normalized to body mass.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be

  6. Weaker lower extremity muscle strength predicts traumatic knee injury in youth female but not male athletes.

    PubMed

    Ryman Augustsson, Sofia; Ageberg, Eva

    2017-01-01

    The role of lower extremity (LE) muscle strength for predicting traumatic knee injury in youth athletes is largely unknown. The aim was to investigate the influence of LE muscle strength on traumatic knee injury in youth female and male athletes. 225 athletes (40% females) from sport senior high schools in Sweden were included in this case-control study. The athletes recorded any traumatic knee injury that had occurred during their high-school period in a web-based injury form. A one repetition maximum (1RM) barbell squat test was used to measure LE muscle strength. The 1RM was dichotomised to analyse 'weak' versus 'strong' athletes according to the median (weak median vs strong median ). 63 traumatic knee injuries, including 18 ACL injuries, were registered. The majority of injured female athletes were in the weak group compared with the strong group (p=0.0001). The odds of sustaining a traumatic knee injury and an ACL injury was 9.5 times higher and 7 times higher, respectively, in the weak median group compared with the strong median group in females (p ≤0.011). A relative 1RM squat ≤1.05 kg (105% of bodyweight) was established as the best cut-off value to distinguish high versus low risk of injury in female athletes. No strength-injury relationships were observed for the male athletes (p ≥0.348). Weaker LE muscle strength predicted traumatic knee injury in youth female athletes, but not in males. This suggests that LE muscle strength should be included in injury screening in youth female athletes.

  7. Effects of combined endurance and strength training on muscle strength, power and hypertrophy in 40-67-year-old men.

    PubMed

    Karavirta, L; Häkkinen, A; Sillanpää, E; García-López, D; Kauhanen, A; Haapasaari, A; Alen, M; Pakarinen, A; Kraemer, W J; Izquierdo, M; Gorostiaga, E; Häkkinen, K

    2011-06-01

    Both strength and endurance training have several positive effects on aging muscle and physical performance of middle-aged and older adults, but their combination may compromise optimal adaptation. This study examined the possible interference of combined strength and endurance training on neuromuscular performance and skeletal muscle hypertrophy in previously untrained 40-67-year-old men. Maximal strength and muscle activation in the upper and lower extremities, maximal concentric power, aerobic capacity and muscle fiber size and distribution in the vastus lateralis muscle were measured before and after a 21-week training period. Ninety-six men [mean age 56 (SD 7) years] completed high-intensity strength training (S) twice a week, endurance training (E) twice a week, combined training (SE) four times per week or served as controls (C). SE and S led to similar gains in one repetition maximum strength of the lower extremities [22 (9)% and 21 (8)%, P<0.001], whereas E and C showed minor changes. Cross-sectional area of type II muscle fibers only increased in S [26 (22)%, P=0.002], while SE showed an inconsistent, non-significant change [8 (35)%, P=0.73]. Combined training may interfere with muscle hypertrophy in aging men, despite similar gains in maximal strength between the strength and the combined training groups. © 2009 John Wiley & Sons A/S.

  8. MicroRNA-155 facilitates skeletal muscle regeneration by balancing pro- and anti-inflammatory macrophages

    PubMed Central

    Nie, M; Liu, J; Yang, Q; Seok, H Y; Hu, X; Deng, Z-L; Wang, D-Z

    2016-01-01

    Skeletal muscle has remarkable regeneration capacity and regenerates in response to injury. Muscle regeneration largely relies on muscle stem cells called satellite cells. Satellite cells normally remain quiescent, but in response to injury or exercise they become activated and proliferate, migrate, differentiate, and fuse to form multinucleate myofibers. Interestingly, the inflammatory process following injury and the activation of the myogenic program are highly coordinated, with myeloid cells having a central role in modulating satellite cell activation and regeneration. Here, we show that genetic deletion of microRNA-155 (miR-155) in mice substantially delays muscle regeneration. Surprisingly, miR-155 does not appear to directly regulate the proliferation or differentiation of satellite cells. Instead, miR-155 is highly expressed in myeloid cells, is essential for appropriate activation of myeloid cells, and regulates the balance between pro-inflammatory M1 macrophages and anti-inflammatory M2 macrophages during skeletal muscle regeneration. Mechanistically, we found that miR-155 suppresses SOCS1, a negative regulator of the JAK-STAT signaling pathway, during the initial inflammatory response upon muscle injury. Our findings thus reveal a novel role of miR-155 in regulating initial immune responses during muscle regeneration and provide a novel miRNA target for improving muscle regeneration in degenerative muscle diseases. PMID:27277683

  9. Effect of quadriceps and hamstrings muscle cooling on standing balance in healthy young men.

    PubMed

    Alghadir, A H; Anwer, S; Zafar, H; Al-Eisa, E S

    2017-09-01

    The present study compared the effect of quadriceps and hamstring muscle cooling on standing balance in healthy young men. Thirty healthy young men (18-30 years) participated in the study. The participants were randomly assigned to three groups (n=10 each): quadriceps cooling (QC), hamstring cooling (HC), or control group (no cooling). Participants in the QC and HC groups received 20 minutes of cooling using a cold pack (gel pack), placed on the anterior thigh (from the apex of the patella to the mid-thigh) and the posterior thigh (from the base of the popliteal fossa to the mid-thigh), respectively. Balance score including unilateral stance was measured at baseline and immediately after the application of the cold pack. No significant difference in the balance score was noted in any group after the application of the cold pack (p⟩0.05). Similarly, no significant differences in post-test balance score were noted among the three groups (p⟩0.05). Cooling of the quadriceps and hamstring muscles has no immediate effect on standing balance in healthy young men. However, longitudinal studies are warranted to investigate the long-term effects of cooling these muscles on standing balance.

  10. The Relationship Between Maximum Unilateral Squat Strength and Balance in Young Adult Men and Women

    PubMed Central

    McCurdy, Kevin; Langford, George

    2006-01-01

    The purpose of this study was to determine the relationship between unilateral squat strength and measures of static balance to compare balance performance between the dominant and non-dominant leg. Seventeen apparently healthy men (mean mass 90.5 ± 20.9 kg and age 21.7 ± 1.8 yrs) and 25 women (mean mass 62.2 ± 14.5 kg and age 21.9 ± 1.3 yrs) completed the study. Weight bearing unilateral strength was measured with a 1RM modified unilateral squat on the dominant and non-dominant leg. The students completed the stork stand and wobble board tests to determine static balance on the dominant and non-dominant leg. Maximum time maintained in the stork stand position, on the ball of the foot with the uninvolved foot against the involved knee with hands on the hips, was recorded. Balance was measured with a 15 second wobble board test. No significant correlations were found between the measurements of unilateral balance and strength (r values ranged between -0.05 to 0.2) for the men and women. Time off balance was not significantly different between the subjects’ dominant (men 1.1 ± 0.4 s; women 0.3 ± 0.1 s) and non-dominant (men 0.9 ± 0.3 s; women 0.3 ± 0.1 s) leg for the wobble board. Similar results were found for the time balanced during the stork stand test on the dominant (men 26.4 ± 6.3 s; women 24.1 ± 5.6 s) and non-dominant (men 26.0 ± 5.7 s; women 21.3 ± 4.1 s) leg. The data indicate that static balance and strength is unrelated in young adult men and women and gains made in one variable after training may not be associated with a change in performance of the other variable. These results also suggest that differences in static balance performance between legs can not be determined by leg dominance. Similar research is needed to compare contralateral leg balance in populations who participate in work or sport activities requiring repetitive asymmetrical use. A better understanding of contralateral balance performance will help practitioners make

  11. Increased muscle strength improves managing in activities of daily living in fall-prone community-dwelling older women.

    PubMed

    Vaapio, Sari; Salminen, Marika; Vahlberg, Tero; Kivelä, Sirkka-Liisa

    2011-02-01

    The aim of this longitudinal study was to describe whether an increase in knee extension strength is associated with improvements in managing in activities of daily living (ADL) and in self-perceived physical condition in fall-prone community-dwelling older women. Subjects (n=417) aged ≥ 65 years belonged either to intervention or control groups in a 12-month randomized controlled fall prevention trial. Isometric muscle strength of knee extension was measured with an adjustable dynamometer chair. Managing in activities of daily living was measured with structured questions about abilities to climb stairs, walk at least 400 meters, toilet, bath, go to the sauna, do light or heavy housework, and carry heavy loads. A question of self-perceived physical condition was also asked. Positive associations were found between increased knee extension strength and an increase in walking at least 400 meters (p<0.001), carrying heavy loads (p=0.004), and climbing stairs (p=0.007), and in self perceived physical condition (p=0.005) over a 12- month follow-up. In addition, low age, non-use of a walking aid, low number of prescribed medications, and good functional balance at baseline were associated with an increase in performance of these ADL functions. An increase in knee extension strength during the 12-month follow-up was associated with improvement in some ADL functions and improvement in self-perceived physical condition during the same period in fall-prone community-dwelling women.

  12. Effects of 5 weeks of lower limb suspension on muscle size and strength

    NASA Technical Reports Server (NTRS)

    Tesch, P. A.; Ploutz, L. L.; Dudley, G. A.

    1994-01-01

    Lack of weight-bearing, as occurs in space, appears to be associated with reductions in strength and mass of skeletal muscle. Very limited data, however, is at hand describing changes in skeletal muscle size and function following manned space missions. Our current knowledge therefore is mainly based on studies of space flown rats. It is obvious though that this information, only in part can be extrapolated to humans. A few bed rest studies have demonstrated that decreases in strength and muscle size are substantial. At this time, however, the magnitude or time course of such changes either in response to space flight or simulations of microgravity have not been defined. In the last few years we have employed a human model to simulate unloading of lower limb skeletal muscles that occurs in microgravity. This model was essentially adopted from the rat hindlimb suspension technique. The purpose of this study was to assess the magnitude of decreases in muscle strength and size as a result of five weeks of unilateral lower limb suspension.

  13. The influence of estradiol on muscle damage and leg strength after intense eccentric exercise.

    PubMed

    Minahan, Clare; Joyce, Sarah; Bulmer, Andrew C; Cronin, Neil; Sabapathy, Surendran

    2015-07-01

    To examine the influence of estradiol on muscle damage and leg strength after intense eccentric exercise. Eight men (MEN), eight normally menstruating women (WomenNM), and eight women using oral contraceptives (WomenOC) participated in this study. Subjects performed 240 maximal-effort bilateral eccentric contractions of the quadriceps muscle groups designed to elicit exercise-induced muscle damage (EiMD). Serum creatine kinase (CK), myoglobin (Mb), and fatty acid-binding protein (FABP) concentrations were measured before (pre-) EiMD, as well as 0, 6, 24, and 48 h post-EiMD. Peak isometric quadriceps torque (i.e., leg strength) was measured pre-EiMD, as well as 24 and 48 h post-EiMD. The increases in CK, Mb, and FABP concentrations from pre- to post-EiMD were greater in MEN (10-fold, 15-fold, and fourfold, respectively) and WomenOC (sevenfold, 11-fold, and ninefold) compared with WomenNM (five-, six-, and threefold; p < 0.05). The decline in leg strength was about 10 % pre- to 24 h post-EiMD in all groups and decreased a further 10-15 % by 48 h post-EiMD in the MEN and WomenOC only. Our findings suggest an important role of estradiol in blunting the muscle damage response to intense eccentric exercise and preserving muscle function after EiMD.

  14. The effect of melatonin treatment on postural stability, muscle strength, and quality of life and sleep in postmenopausal women: a randomized controlled trial.

    PubMed

    Amstrup, Anne Kristine; Sikjaer, Tanja; Mosekilde, Leif; Rejnmark, Lars

    2015-09-30

    Melatonin is often used as a sleeping aid in elderly adults. As previous studies suggest a protective role of melatonin against osteoporosis, it is important to document its safety. Treatment should not cause any hangover effect that could potentially lead to falls and fractures. We therefore aimed to evaluate the effect of melatonin on balance- and muscle function. In a double-blind placebo-controlled study, we randomized 81 postmenopausal women with osteopenia to receive 1 or 3 mg melatonin, or placebo nightly for 12 months. Postural balance as well as muscle function was measured. In addition, we assessed quality of life and sleep at baseline and after 12 months treatment. Compared to placebo, one-year treatment with melatonin did not affect postural balance or risk of falls. Furthermore, no significant changes between groups were observed in muscle strength in neither upper- nor lower extremities. Treatment did not affect quality of life or sleep. However, in the subgroup of women with sleep disturbances at baseline, a trend towards an improved sleep quality was seen (p = 0.08). Treatment with melatonin is safe in postmenopausal women with osteopenia. There is no hangover effect affecting balance- and muscle function following the intake of melatonin. In women with a good quality of sleep, melatonin has no effect, however in poor quality of sleep, small doses of melatonin trended towards improving the quality. (# NCT01690000).

  15. Two Pilot Studies of the Effect of Bicycling on Balance and Leg Strength among Older Adults

    PubMed Central

    Rissel, Chris; Passmore, Erin; Mason, Chloe; Merom, Dafna

    2013-01-01

    Objectives. Study 1 examines whether age-related declines in balance are moderated by bicycling. Study 2 tests whether regular cycling can increase leg strength and improve balance. Methods. Study 1: a cross-sectional survey of 43 adults aged 44–79 was conducted. Leg strength was measured, and Balance was measured using the choice stepping reaction time (CSRT) test (decision time and response time), leg strength and timed single leg standing. Study 2: 18 older adults aged 49–72 were recruited into a 12-week cycling program. The same pre- and postmeasures as used in Study 1 were collected. Results. Study 1: participants who had cycled in the last month performed significantly better on measures of decision time and response time. Study 2: cycling at least one hour a week was associated with significant improvements in balance (decision time and response time) and timed single leg standing. Conclusions. Cycling by healthy older adults appears promising for improving risk factors for falls. PMID:23690805

  16. Walking performance and muscle strength in the later stage poststroke: a nonlinear relationship.

    PubMed

    Carvalho, Cristiane; Sunnerhagen, Katharina S; Willén, Carin

    2013-05-01

    To evaluate the relation between muscle strength in the lower extremities and walking performance (speed and distance) in subjects in the later stage poststroke and to compare this with normative data. A cross-sectional observational study. University hospital department. Subjects poststroke (n=41; 31 men, 10 women) with a mean age of 59±5.8 years and a time from stroke onset of 52±36 months were evaluated. An urban sample (n=144) of 40- to 79-year-olds (69 men, 75 women) formed the healthy reference group. Not applicable. Muscle strength in the lower extremities was measured with an isokinetic dynamometer and combined into a strength index. Values for the 30-meter walk test for self-selected and maximum speed and the 6-minute walk test were measured. A nonlinear regression model was used. The average strength index was 730±309 in the subjects after stroke compared with 1112±362 in the healthy group. A nonlinear relation between walking performance and muscle strength was evident. The model explained 37% of the variance in self-selected speed in the stroke group and 20% in the healthy group, and 63% and 38%, respectively, in the maximum walking speed. For the 6-minute walk test, the model explained 44% of the variance in the stroke group. Subjects in the later stage poststroke were weaker than the healthy reference group, and their weakness was associated with walking performance. At the same strength index, subjects walked at lower speeds and shorter distances after stroke, indicating that there are multiple impairments that affect walking ability. Treatments focused on increasing muscle strength thus continue to hold promise. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  17. Relationship between lower limb muscle strength and 6-minute walk test performance in stroke patients.

    PubMed

    Pradon, Didier; Roche, Nicolas; Enette, Lievyn; Zory, Raphaël

    2013-01-01

    The aim of this study was to determine if lower limb muscle strength and/or spasticity are related to performance in the 6-min walk test (6MWT) in stroke patients. A total of 24 patients (12 males and 12 females) participated in the study. Muscle strength (Medical Research Council (MRC) scale) and spasticity (modified Ashworth scale) were assessed prior to the 6MWT. Heart rate was recorded at rest and during the 6MWT. Subjects were divided into two groups: (i) those with a high MRC sum score, and (ii) those with a low MRC sum score. The relationship between the 6MWT distance and the other parameters was analysed using a Spearman's rank correlation coefficient. There was a significant and positive relationship between 6MWT distance and lower limb muscle strength (p = 0.001), whereas no significant correlations were found between the 6MWT distance and spasticity, resting heart rate and heart rate during the 6MWT. The 6MWT distance may be a good indicator of lower limb muscle strength, and lower limb strengthening may improve gait capacity in stroke patients.

  18. Effects of trunk stability on isometric knee extension muscle strength measurement while sitting.

    PubMed

    Hirano, Masahiro; Gomi, Masahiro; Katoh, Munenori

    2016-09-01

    [Purpose] This study aimed to investigate the effect of trunk stability on isometric knee extension muscle strength measurement while sitting by performing simultaneous measurements with a handheld dynamometer (HHD) and an isokinetic dynamometer (IKD) in the same seated condition. [Subjects and Methods] The subjects were 30 healthy volunteers. Isometric knee extension muscle strength was simultaneously measured with a HHD and an IKD by using an IKD-specific chair. The measurement was performed twice. Measurement instrument variables and the number of measurements were examined by using the analysis of variance and correlation tests. [Results] The measurement instrument variables and the number of measurements were not significantly different. The correlation coefficients between the HHD and IKD measurements were ≥0.96. [Conclusion] Isometric knee extension muscle strength measurement using the HHD in the sitting position resulted in a lower value than that using the IKD, presumably because of the effect of trunk stability on the measurement. In the same seated posture with trunk stability, no significant difference in measurement values was observed between the HHD and IKD. The present findings suggest that trunk stability while seated during isometric knee extension muscle strength measurement influenced the HHD measurement.

  19. The Effects of a 10-Kilometer Run on Muscle Strength and Power.

    ERIC Educational Resources Information Center

    Gomez, Ana L.; Radzwich, Robert J.; Denegar, Craig R.; Volek, Jeff S.; Rubin, Martyn R.; Bush, Jill A.; Doan, Brandon K.; Wickham, Robbin B.; Mazzetti, Scott A.; Newton, Robert U.; French, Duncan N.; Hakkinen, Keijo; Ratamess, Nicholas A.; Kraemer, William J.

    2002-01-01

    Investigated recovery of maximal force and power following a 10-km race. Data collected on 10 healthy male distance runners pre-race, immediately post-race, and 48 hours later indicated that strength and power capabilities of these 10-km runners were for the most part restored 48 hours after the race. Only the hamstring muscle group was not fully…

  20. Relationships between Respiratory Muscle Strength and Daily Living Function in Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Wang, Hui-Yi; Chen, Chien-Chih; Hsiao, Shih-Fen

    2012-01-01

    Cerebral palsy (CP) is a common childhood disorder characterized by motor disability. Children with CP are at risk of developing significant respiratory problems associated with insufficient respiratory muscle strength. It is crucial to identify important factors which are associated with the limitations in daily living function in such children.…

  1. Better Strength, Better Balance! Partnering to deliver a fall prevention program for older adults.

    PubMed

    Taing, Darcie; McKay, Kelly

    2017-09-14

    Falls incur significant health and economic costs, particularly among older adults. Physical activity has been found to be the single most important fall prevention behaviour an older adult can do. This manuscript describes Ottawa Public Health's (OPH) experience implementing the Better Strength, Better Balance! (BSBB) program, a fall prevention exercise program for older adults, through an innovative partnership with the local Recreation, Cultural & Facility Services (RCFS) Department. BSBB aims to reach 1300 community-dwelling adults (aged 65 years and older) per year through approximately 86-130 exercise programs. Designed as a universal program, BSBB addresses participation barriers such as transportation, cost and location. BSBB was enabled with funding from the Champlain Local Health Integration Network, and coincided with the implementation of an Older Adult Plan for the City of Ottawa. BSBB is a beginner-level, fall prevention exercise and education program that takes place twice a week, over 12 weeks. Certified RCFS instructors delivered the exercise components of the program and OPH staff incorporated fall prevention messaging and conducted the evaluation. The formative evaluation indicated that participants experienced improved strength and balance, decreased fear of falling and the intent to adopt new fall prevention behaviours following the program. The partnership between OPH and RCFS allowed both partners to leverage their unique and mutual strengths to continually improve the program. Improving access to strength and balance programming is an important public health strategy to reduce falls. The recreation sector is an ideal partner to help public health in this pursuit.

  2. Reliability of the Q Force; a mobile instrument for measuring isometric quadriceps muscle strength.

    PubMed

    Douma, K W; Regterschot, G R H; Krijnen, W P; Slager, G E C; van der Schans, C P; Zijlstra, W

    2016-01-01

    The ability to generate muscle strength is a pre-requisite for all human movement. Decreased quadriceps muscle strength is frequently observed in older adults and is associated with a decreased performance and activity limitations. To quantify the quadriceps muscle strength and to monitor changes over time, instruments and procedures with a sufficient reliability are needed. The Q Force is an innovative mobile muscle strength measurement instrument suitable to measure in various degrees of extension. Measurements between 110 and 130° extension present the highest values and the most significant increase after training. The objective of this study is to determine the test-retest reliability of muscle strength measurements by the Q Force in older adults in 110° extension. Forty-one healthy older adults, 13 males and 28 females were included in the study. Mean (SD) age was 81.9 (4.89) years. Isometric muscle strength of the Quadriceps muscle was assessed with the Q Force at 110° of knee extension. Participants were measured at two sessions with a three to eight day interval between sessions. To determine relative reliability, the intraclass correlation coefficient (ICC) was calculated. To determine absolute reliability, Bland and Altman Limits of Agreement (LOA) were calculated and t-tests were performed. Relative reliability of the Q Force is good to excellent as all ICC coefficients are higher than 0.75. Generally a large 95 % LOA, reflecting only moderate absolute reliability, is found as exemplified for the peak torque left leg of -18.6 N to 33.8 N and the right leg of -9.2 N to 26.4 N was between 15.7 and 23.6 Newton representing 25.2 % to 39.9 % of the size of the mean. Small systematic differences in mean were found between measurement session 1 and 2. The present study shows that the Q Force has excellent relative test-retest reliability, but limited absolute test-retest reliability. Since the Q Force is relatively cheap and mobile it is suitable for

  3. The evaluation of a strength and balance exercise program for falls prevention in community primary care.

    PubMed

    Hawley-Hague, Helen; Roden, Amy; Abbott, Jo

    2017-08-01

    We aimed to evaluate a strength and balance program delivered in the community. There is little evidence of implementation of evidence-based exercise in practice. The program was a step-down model, designed to encourage long-term exercise in community classes. The program consisted of a fully funded referral only evidence-based 12-week strength and balance (Community Otago) class, followed by an evidence-based continuous open-access community strength and balance class (Active Always). The program was offered to patients: 1) after formal falls rehabilitation (falls and fracture service); 2) after falls rehabilitation in intermediate care; and 3) referred by a GP who were not eligible for rehabilitation (preventative measure). Outcome evaluation used descriptive statistics to report changes in function, confidence in balance, hospital attendance/admission for falls/fractures and transition to community classes. Focus groups established participant experience/satisfaction. Seventy-nine participants were included, aged 56-96, and 53 (67%) were women. About 63.3% of patients transitioned to Active Always classes, demonstrating improvement in maintenance. Follow-up scores from baseline attendance at falls and fracture service to 12-weeks follow-up (24 weeks) in Community Otago showed the majority of patients improved their function (Timed up and Go), confidence (ConfBal) and lowered their falls risk (Tinetti). Follow-up of participants from Community Otago baseline to the end of 12-weeks showed improvement in function and confidence, but only a third of participants lowered their falls risk. Focus groups data suggest that continuity of delivery, the role of the instructor, health professional, and social and physical outcomes were essential for maintenance. A supportive environment can be created which encourages older adults' continued participation in group-based strength and balance, helping the delivery of evidence-based practice.

  4. Inference on the Strength of Balancing Selection for Epistatically Interacting Loci

    PubMed Central

    Buzbas, Erkan Ozge; Joyce, Paul; Rosenberg, Noah A.

    2011-01-01

    Existing inference methods for estimating the strength of balancing selection in multi-locus genotypes rely on the assumption that there are no epistatic interactions between loci. Complex systems in which balancing selection is prevalent, such as sets of human immune system genes, are known to contain components that interact epistatically. Therefore, current methods may not produce reliable inference on the strength of selection at these loci. In this paper, we address this problem by presenting statistical methods that can account for epistatic interactions in making inference about balancing selection. A theoretical result due to Fearnhead (2006) is used to build a multi-locus Wright-Fisher model of balancing selection, allowing for epistatic interactions among loci. Antagonistic and synergistic types of interactions are examined. The joint posterior distribution of the selection and mutation parameters is sampled by Markov chain Monte Carlo methods, and the plausibility of models is assessed via Bayes factors. As a component of the inference process, an algorithm to generate multi-locus allele frequencies under balancing selection models with epistasis is also presented. Recent evidence on interactions among a set of human immune system genes is introduced as a motivating biological system for the epistatic model, and data on these genes are used to demonstrate the methods. PMID:21277883

  5. Effect of Combined Sensorimotor-Resistance Training on Strength, Balance, and Jumping Performance of Soccer Players.

    PubMed

    Manolopoulos, Konstantinos; Gissis, Ioannis; Galazoulas, Christos; Manolopoulos, Evaggelos; Patikas, Dimitrios; Gollhofer, Albert; Kotzamanidis, Christos

    2016-01-01

    The purpose of the study was to investigate the effects of resistance training (RT) and sensorimotor training combined with RT (SM-RT) on balance, 1 repetition maximum (RM), rate of force development (RFD), and squat jump (SJ) height. Twenty amateur soccer players were equally divided into 2 groups assigned as SM-RT group (age: 22 ± 1.7 years, body mass: 79.9 ± 6.3 kg, body height: 1.81 ± 0.06 m) and RT group (age: 21.3 ± 1.3 years, body mass: 77.4 ± 9.3 kg, body height: 1.78 ± 0.04 m). Both groups were trained over a 6-week period with 2 session units per week. SM-RT group performed sensorimotor training (balance on balance board) followed by a high-intensity RT at 8-5RM leg press. The RT group performed the resistance program only. Both groups showed significantly increased 1RM leg press strength, RFD, SJ height, and balance abilities (p ≤ 0.05), whereas no significant between-group differences were observed in any of the outcome variables (p > 0.05). It was concluded that SM-RT was not superior compared with RT for both balance and strength enhancement. These findings have implications in time management during training for soccer players.

  6. Contributions of neural excitability and voluntary activation to quadriceps muscle strength following anterior cruciate ligament reconstruction.

    PubMed

    Lepley, Adam S; Ericksen, Hayley M; Sohn, David H; Pietrosimone, Brian G

    2014-06-01

    Persistent quadriceps weakness is common following anterior cruciate ligament reconstruction (ACLr). Alterations in spinal-reflexive excitability, corticospinal excitability and voluntary activation have been hypothesized as underlying mechanisms contributing to quadriceps weakness. The aim of this study was to evaluate the predictive capabilities of spinal-reflexive excitability, corticospinal excitability and voluntary activation on quadriceps strength in healthy and ACLr participants. Quadriceps strength was measured using maximal voluntary isometric contractions (MVIC). Voluntary activation was quantified via the central activation ratio (CAR). Corticospinal and spinal-reflexive excitability were measured using active motor thresholds (AMT) and Hoffmann reflexes normalized to maximal muscle responses (H:M), respectively. ACLr individuals were also split into high and low strength subsets based on MVIC. CAR was the only significant predictor in the healthy group. In the ACLr group, CAR and H:M significantly predicted 47% of the variance in MVIC. ACLr individuals in the high strength subset demonstrated significantly higher CAR and H:M than those in the low strength subset. Increased quadriceps voluntary activation, spinal-reflexive excitability and corticospinal excitability relates to increased quadriceps strength in participants following ACLr. Rehabilitation strategies used to target neural alterations may be beneficial for the restoration of muscle strength following ACLr. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Strength characterization of knee flexor and extensor muscles in Prader-Willi and obese patients

    PubMed Central

    Capodaglio, Paolo; Vismara, Luca; Menegoni, Francesco; Baccalaro, Gabriele; Galli, Manuela; Grugni, Graziano

    2009-01-01

    Background despite evidence of an obesity-related disability, there is a lack of objective muscle functional data in overweight subjects. Only few studies provide instrumental strength measurements in non-syndromal obesity, whereas no data about Prader-Willi syndrome (PWS) are reported. The aim of our study was to characterize the lower limb muscle function of patients affected by PWS as compared to non-syndromal obesity and normal-weight subjects. Methods We enrolled 20 obese (O) females (age: 29.1 ± 6.5 years; BMI: 38.1 ± 3.1), 6 PWS females (age: 27.2 ± 4.9 years; BMI: 45.8 ± 4.4) and 14 healthy normal-weight (H) females (age: 30.1 ± 4.7 years; BMI: 21 ± 1.6). Isokinetic strength during knee flexion and extension in both lower limbs at the fixed angular velocities of 60°/s, 180°/s, 240°/s was measured with a Cybex Norm dynamometer. Results the H, O and PWS populations appear to be clearly stratified with regard to muscle strength.: PWS showed the lowest absolute peak torque (PT) for knee flexor and extensor muscles as compared to O (-55%) and H (-47%) (P = 0.00001). O showed significantly higher strength values than H as regard to knee extension only (P = 0.0014). When strength data were normalised by body weight, PWS showed a 50% and a 70% reduction in PT as compared to O and H, respectively. Knee flexors strength values were on average half of those reported for extension in all of the three populations. Conclusion the novel aspect of our study is the determination of objective measures of muscle strength in PWS and the comparison with O and H patients. The objective characterization of muscle function performed in this study provides baseline and outcome measures that may quantify specific strength deficits amendable with tailored rehabilitation programs and monitor effectiveness of treatments. PMID:19419559

  8. Effects of Training Attendance on Muscle Strength of Young Men after 11 Weeks of Resistance Training

    PubMed Central

    Gentil, Paulo; Bottaro, Martim

    2013-01-01

    Purpose Training attendance is an important variable for attaining optimal results after a resistance training (RT) program, however, the association of attendance with the gains of muscle strength is not well defined. Therefore, the purpose of the present study is to verify if attendance would affect muscle strength gains in healthy young males. Methods Ninety two young males with no previous RT experience volunteered to participate in the study. RT was performed 2 days a week for 11 weeks. One repetition maximum (1RM) in the bench press and knee extensors peak torque (PT) were measured before and after the training period. After the training period, a two step cluster analysis was used to classify the participants in accordance to training attendance, resulting in three groups, defined as high (92 to 100%), intermediate (80 to 91%) and low (60 to 79%) training attendance. Results According to the results, there were no significant correlations between strength gains and training attendance, however, when attendance groups were compared, the low training attendance group showed lower increases in 1RM bench press (8.8%) than the other two groups (17.6% and 18.0% for high and intermediate attendance, respectively). Conclusions Although there is not a direct correlation between training attendance and muscle strength gains, it is suggested that a minimum attendance of 80% is necessary to ensure optimal gains in upper body strength. PMID:23802051

  9. Functional Capacity in Adults With Cerebral Palsy: Lower Limb Muscle Strength Matters.

    PubMed

    Gillett, Jarred G; Lichtwark, Glen A; Boyd, Roslyn N; Barber, Lee A

    2018-05-01

    To investigate the relation between lower limb muscle strength, passive muscle properties, and functional capacity outcomes in adults with cerebral palsy (CP). Cross-sectional study. Tertiary institution biomechanics laboratory. Adults with spastic-type CP (N=33; mean age, 25y; range, 15-51y; mean body mass, 70.15±21.35kg) who were either Gross Motor Function Classification System (GMFCS) level I (n=20) or level II (n=13). Not applicable. Six-minute walk test (6MWT) distance (m), lateral step-up (LSU) test performance (total repetitions), timed up-stairs (TUS) performance (s), maximum voluntary isometric strength of plantar flexors (PF) and dorsiflexors (DF) (Nm.kg -1 ), and passive ankle joint and muscle stiffness. Maximum isometric PF strength independently explained 61% of variance in 6MWT performance, 57% of variance in LSU test performance, and 50% of variance in TUS test performance. GMFCS level was significantly and independently related to all 3 functional capacity outcomes, and age was retained as a significant independent predictor of LSU and TUS test performance. Passive medial gastrocnemius muscle fascicle stiffness and ankle joint stiffness were not significantly related to functional capacity measures in any of the multiple regression models. Low isometric PF strength was the most important independent variable related to distance walked on the 6MWT, fewer repetitions on the LSU test, and slower TUS test performance. These findings suggest lower isometric muscle strength contributes to the decline in functional capacity in adults with CP. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  10. Weaker lower extremity muscle strength predicts traumatic knee injury in youth female but not male athletes

    PubMed Central

    Ryman Augustsson, Sofia; Ageberg, Eva

    2017-01-01

    Background The role of lower extremity (LE) muscle strength for predicting traumatic knee injury in youth athletes is largely unknown. Aims The aim was to investigate the influence of LE muscle strength on traumatic knee injury in youth female and male athletes. Methods 225 athletes (40% females) from sport senior high schools in Sweden were included in this case–control study. The athletes recorded any traumatic knee injury that had occurred during their high-school period in a web-based injury form. A one repetition maximum (1RM) barbell squat test was used to measure LE muscle strength. The 1RM was dichotomised to analyse ‘weak’ versus ‘strong’ athletes according to the median (weakmedian vs strongmedian). Results 63 traumatic knee injuries, including 18 ACL injuries, were registered. The majority of injured female athletes were in the weak group compared with the strong group (p=0.0001). The odds of sustaining a traumatic knee injury and an ACL injury was 9.5 times higher and 7 times higher, respectively, in the weakmedian group compared with the strongmedian group in females (p ≤0.011). A relative 1RM squat ≤1.05 kg (105% of bodyweight) was established as the best cut-off value to distinguish high versus low risk of injury in female athletes. No strength–injury relationships were observed for the male athletes (p ≥0.348). Conclusions Weaker LE muscle strength predicted traumatic knee injury in youth female athletes, but not in males. This suggests that LE muscle strength should be included in injury screening in youth female athletes. PMID:29259807

  11. Mobility and muscle strength in male former elite endurance and power athletes aged 66-91 years.

    PubMed

    Manderoos, S; Wasenius, N; Laine, M K; Kujala, U M; Mälkiä, E; Kaprio, J; Sarna, S; Bäckmand, H M; Kettunen, J A; Heinonen, O J; Jula, A M; Aunola, S; Eriksson, J G

    2017-11-01

    The aim of this cross-sectional study was to compare mobility and muscle strength in male former elite endurance and power athletes aged 66-91 years (n = 150; 50 men in both former elite athlete groups and in their control group). Agility, dynamic balance, walking speed, chair stand, self-rated balance confidence (ABC-scale), jumping height, and handgrip strength were assessed. Former elite power athletes had better agility performance time than the controls (age- and body mass index, BMI-adjusted mean difference -3.6 s; 95% CI -6.3, -0.8). Adjustment for current leisure time physical activity (LTPA) and prevalence of diseases made this difference non-significant (P = 0.214). The subjects in the power sports group jumped higher than the men in the control group (age- and BMI-adjusted mean differences for vertical squat jump, VSJ 4.4 cm; 95% CI 2.0, 6.8; for countermovement jump, CMJ 4.0 cm; 95% CI 1.7, 6.4). Taking current LTPA and chronic diseases for adjusting process did not improve explorative power of the model. No significant differences between the groups were found in the performances evaluating dynamic balance, walking speed, chair stand, ABC-scale, or handgrip strength. In conclusion, power athletes among the aged former elite sportsmen had greater explosive force production in their lower extremities than the men in the control group. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Rehabilitation Exercises to Induce Balanced Scapular Muscle Activity in an Anti-gravity Posture.

    PubMed

    Ishigaki, Tomonobu; Yamanaka, Masanori; Hirokawa, Motoki; Tai, Keita; Ezawa, Yuya; Samukawa, Mina; Tohyama, Harukazu; Sugawara, Makoto

    2014-12-01

    [Purpose] The purpose of this study was to compare the intramuscular balance ratios of the upper trapezius muscle (UT) and the lower trapezius muscle (LT), and the intermuscular balance ratios of the UT and the serratus anterior muscle (SA) among prone extension (ProExt), prone horizontal abduction with external rotation (ProHAbd), forward flexion in the side-lying position (SideFlex), side-lying external rotation (SideEr), shoulder flexion with glenohumeral horizontal abduction load (FlexBand), and shoulder flexion with glenohumeral horizontal adduction load (FlexBall) in the standing posture. [Methods] The electromyographic (EMG) activities of the UT, LT and SA were measured during the tasks. The percentage of maximum voluntary isometric contraction (%MVIC) was calculated for each muscle, and the UT/LT ratios and the UT/SA ratios were compared among the tasks. [Results] The UT/LT ratio with the FlexBand was not significantly different from those of the four exercises in the side-lying and prone postures. The UT/SA ratio with the FlexBall demonstrated appropriate balanced activity. [Conclusion] In an anti-gravity posture, we recommend the FlexBand and the FlexBall for inducing balanced UT/LT and UT/SA ratios, respectively.

  13. Rehabilitation Exercises to Induce Balanced Scapular Muscle Activity in an Anti-gravity Posture

    PubMed Central

    Ishigaki, Tomonobu; Yamanaka, Masanori; Hirokawa, Motoki; Tai, Keita; Ezawa, Yuya; Samukawa, Mina; Tohyama, Harukazu; Sugawara, Makoto

    2014-01-01

    [Purpose] The purpose of this study was to compare the intramuscular balance ratios of the upper trapezius muscle (UT) and the lower trapezius muscle (LT), and the intermuscular balance ratios of the UT and the serratus anterior muscle (SA) among prone extension (ProExt), prone horizontal abduction with external rotation (ProHAbd), forward flexion in the side-lying position (SideFlex), side-lying external rotation (SideEr), shoulder flexion with glenohumeral horizontal abduction load (FlexBand), and shoulder flexion with glenohumeral horizontal adduction load (FlexBall) in the standing posture. [Methods] The electromyographic (EMG) activities of the UT, LT and SA were measured during the tasks. The percentage of maximum voluntary isometric contraction (%MVIC) was calculated for each muscle, and the UT/LT ratios and the UT/SA ratios were compared among the tasks. [Results] The UT/LT ratio with the FlexBand was not significantly different from those of the four exercises in the side-lying and prone postures. The UT/SA ratio with the FlexBall demonstrated appropriate balanced activity. [Conclusion] In an anti-gravity posture, we recommend the FlexBand and the FlexBall for inducing balanced UT/LT and UT/SA ratios, respectively. PMID:25540485

  14. The effects of isolated ankle strengthening and functional balance training on strength, running mechanics, postural control and injury prevention in novice runners: design of a randomized controlled trial.

    PubMed

    Baltich, Jennifer; Emery, Carolyn A; Stefanyshyn, Darren; Nigg, Benno M

    2014-12-04

    Risk factors have been proposed for running injuries including (a) reduced muscular strength, (b) excessive joint movements and (c) excessive joint moments in the frontal and transverse planes. To date, many running injury prevention programs have focused on a "top down" approach to strengthen the hip musculature in the attempt to reduce movements and moments at the hip, knee, and/or ankle joints. However, running mechanics did not change when hip muscle strength increased. It could be speculated that emphasis should be placed on increasing the strength of the ankle joint for a "ground up" approach. Strengthening of the large and small muscles crossing the ankle joint is assumed to change the force distribution for these muscles and to increase the use of smaller muscles. This would be associated with a reduction of joint and insertion forces, which could have a beneficial effect on injury prevention. However, training of the ankle joint as an injury prevention strategy has not been studied. Ankle strengthening techniques include isolated strengthening or movement-related strengthening such as functional balance training. There is little knowledge about the efficacy of such training programs on strength alteration, gait or injury reduction. Novice runners will be randomly assigned to one of three groups: an isolated ankle strengthening group (strength, n = 40), a functional balance training group (balance, n = 40) or an activity-matched control group (control, n = 40). Isokinetic strength will be measured using a Biodex System 3 dynamometer. Running kinematics and kinetics will be assessed using 3D motion analysis and a force platform. Postural control will be assessed by quantifying the magnitude and temporal structure of the center of pressure trace during single leg stance on a force platform. The change pre- and post-training in isokinetic strength, running mechanics, and postural control variables will be compared following the interventions

  15. Joint laxity and the relationship between muscle strength and functional ability in patients with osteoarthritis of the knee.

    PubMed

    van der Esch, M; Steultjens, M; Knol, D L; Dinant, H; Dekker, J

    2006-12-15

    To establish the impact of knee joint laxity on the relationship between muscle strength and functional ability in osteoarthritis (OA) of the knee. A cross-sectional study of 86 patients with OA of the knee was conducted. Tests were performed to determine varus-valgus laxity, muscle strength, and functional ability. Laxity was assessed using a device that measures the angular deviation of the knee in the frontal plane. Muscle strength was measured using a computer-driven isokinetic dynamometer. Functional ability was assessed by observation (100-meter walking test) and self report (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]). Regression analyses were performed to assess the impact of joint laxity on the relationship between muscle strength and functional ability. In regression analyses, the interaction between muscle strength and joint laxity contributed to the variance in both walking time (P = 0.002) and WOMAC score (P = 0.080). The slope of the regression lines indicated that the relationship between muscle strength and functional ability (walking time, WOMAC) was stronger in patients with high knee joint laxity. Patients with knee OA and high knee joint laxity show a stronger relationship between muscle strength and functional ability than patients with OA and low knee joint laxity. Patients with OA, high knee joint laxity, and low muscle strength are most at risk of being disabled.

  16. Relationships Between Lower-Body Muscle Structure and Lower-Body Strength, Power, and Muscle-Tendon Complex Stiffness.

    PubMed

    Secomb, Josh L; Lundgren, Lina E; Farley, Oliver R L; Tran, Tai T; Nimphius, Sophia; Sheppard, Jeremy M

    2015-08-01

    The purpose of this study was to determine whether any relationships were present between lower-body muscle structure and strength and power qualities. Fifteen elite male surfing athletes performed a battery of lower-body strength and power tests, including countermovement jump (CMJ), squat jump (SJ), isometric midthigh pull (IMTP), and had their lower-body muscle structure assessed with ultrasonography. In addition, lower-body muscle-tendon complex (MTC) stiffness and dynamic strength deficit (DSD) ratio were calculated from the CMJ and IMTP. Significant relationships of large to very large strength were observed between the vastus lateralis (VL) thickness of the left (LVL) and right (RVL) leg and peak force (PF) (r = 0.54-0.77, p < 0.01-0.04), peak velocity (PV) (r = 0.66-0.83, p < 0.01), and peak jump height (r = 0.62-0.80, p < 0.01) in the CMJ and SJ, as well as IMTP PF (r = 0.53-0.60, p = 0.02-0.04). Furthermore, large relationships were found between left lateral gastrocnemius (LG) pennation angle and SJ and IMTP PF (r = 0.53, p = 0.04, and r = 0.70, p < 0.01, respectively) and between LG and IMTP relative PF (r = 0.63, p = 0.01). Additionally, large relationships were identified between lower-body MTC stiffness and DSD ratio (r = 0.68, p < 0.01), right (LG) pennation angle (r = 0.51, p = 0.05), CMJ PF (r = 0.60, p = 0.02), and jump height (r = 0.53, p = 0.04). These results indicate that greater VL thickness and increased LG pennation angle are related to improved performance in the CMJ, SJ, and IMTP. Furthermore, these results suggest that lower-body MTC stiffness explains a large amount of variance in determining an athlete's ability to rapidly apply force during a dynamic movement.

  17. Validity and test–retest reliability of a novel simple back extensor muscle strength test

    PubMed Central

    Harding, Amy T; Weeks, Benjamin Kurt; Horan, Sean A; Little, Andrew; Watson, Steven L; Beck, Belinda Ruth

    2017-01-01

    Objectives: To develop and determine convergent validity and reliability of a simple and inexpensive clinical test to quantify back extensor muscle strength. Methods: Two testing sessions were conducted, 7 days apart. Each session involved three trials of standing maximal isometric back extensor muscle strength using both the novel test and isokinetic dynamometry. Lumbar spine bone mineral density was examined by dual-energy X-ray absorptiometry. Validation was examined with Pearson correlations (r). Test–retest reliability was examined with intraclass correlation coefficients and limits of agreement. Pearson correlations and intraclass correlation coefficients are presented with corresponding 95% confidence intervals. Linear regression was used to examine the ability of peak back extensor muscle strength to predict indices of lumbar spine bone mineral density and strength. Results: A total of 52 healthy adults (26 men, 26 women) aged 46.4 ± 20.4 years were recruited from the community. A strong positive relationship was observed between peak back extensor strength from hand-held and isokinetic dynamometry (r = 0.824, p < 0.001). For the novel back extensor strength test, short- and long-term reliability was excellent (intraclass correlation coefficient = 0.983 (95% confidence interval, 0.971–0.990), p < 0.001 and intraclass correlation coefficient = 0.901 (95% confidence interval, 0.833–0.943), p < 0.001, respectively). Limits of agreement for short-term repeated back extensor strength measures with the novel back extensor strength protocol were −6.63 to 7.70 kg, with a mean bias of +0.71 kg. Back extensor strength predicted 11% of variance in lumbar spine bone mineral density (p < 0.05) and 9% of lumbar spine index of bone structural strength (p < 0.05). Conclusion: Our novel hand-held dynamometer method to determine back extensor muscle strength is quick, relatively inexpensive, and reliable; demonstrates

  18. Anti-myostatin antibody increases muscle mass and strength and improves insulin sensitivity in old mice.

    PubMed

    Camporez, João-Paulo G; Petersen, Max C; Abudukadier, Abulizi; Moreira, Gabriela V; Jurczak, Michael J; Friedman, Glenn; Haqq, Christopher M; Petersen, Kitt Falk; Shulman, Gerald I

    2016-02-23

    Sarcopenia, or skeletal muscle atrophy, is a debilitating comorbidity of many physiological and pathophysiological processes, including normal aging. There are no approved therapies for sarcopenia, but the antihypertrophic myokine myostatin is a potential therapeutic target. Here, we show that treatment of young and old mice with an anti-myostatin antibody (ATA 842) for 4 wk increased muscle mass and muscle strength in both groups. Furthermore, ATA 842 treatment also increased insulin-stimulated whole body glucose metabolism in old mice, which could be attributed to increased insulin-stimulated skeletal muscle glucose uptake as measured by a hyperinsulinemic-euglycemic clamp. Taken together, these studies provide support for pharmacological inhibition of myostatin as a potential therapeutic approach for age-related sarcopenia and metabolic disease.

  19. The Him gene reveals a balance of inputs controlling muscle differentiation in Drosophila.

    PubMed

    Liotta, David; Han, Jun; Elgar, Stuart; Garvey, Clare; Han, Zhe; Taylor, Michael V

    2007-08-21

    Tissue development requires the controlled regulation of cell-differentiation programs. In muscle, the Mef2 transcription factor binds to and activates the expression of many genes and has a major positive role in the orchestration of differentiation. However, little is known about how Mef2 activity is regulated in vivo during development. Here, we characterize a gene, Holes in muscle (Him), which our results indicate is part of this control in Drosophila. Him expression rapidly declines as embryonic muscle differentiates, and consistent with this, Him overexpression inhibits muscle differentiation. This inhibitory effect is suppressed by mef2, implicating Him in the mef2 pathway. We then found that Him downregulates the transcriptional activity of Mef2 in both cell culture and in vivo. Furthermore, Him protein binds Groucho, a conserved, transcriptional corepressor, through a WRPW motif and requires this motif and groucho function to inhibit both muscle differentiation and Mef2 activity during development. Together, our results identify a mechanism that can inhibit muscle differentiation in vivo. We conclude that a balance of positive and negative inputs, including Mef2, Him, and Groucho, controls muscle differentiation during Drosophila development and suggest that one outcome is to hold developing muscle cells in a state with differentiation genes poised to be expressed.

  20. The Him Gene Reveals a Balance of Inputs Controlling Muscle Differentiation in Drosophila

    PubMed Central

    Liotta, David; Han, Jun; Elgar, Stuart; Garvey, Clare; Han, Zhe; Taylor, Michael V.

    2007-01-01

    Summary Tissue development requires the controlled regulation of cell-differentiation programs. In muscle, the Mef2 transcription factor binds to and activates the expression of many genes and has a major positive role in the orchestration of differentiation [1–4]. However, little is known about how Mef2 activity is regulated in vivo during development. Here, we characterize a gene, Holes in muscle (Him), which our results indicate is part of this control in Drosophila. Him expression rapidly declines as embryonic muscle differentiates, and consistent with this, Him overexpression inhibits muscle differentiation. This inhibitory effect is suppressed by mef2, implicating Him in the mef2 pathway. We then found that Him downregulates the transcriptional activity of Mef2 in both cell culture and in vivo. Furthermore, Him protein binds Groucho, a conserved, transcriptional corepressor, through a WRPW motif and requires this motif and groucho function to inhibit both muscle differentiation and Mef2 activity during development. Together, our results identify a mechanism that can inhibit muscle differentiation in vivo. We conclude that a balance of positive and negative inputs, including Mef2, Him, and Groucho, controls muscle differentiation during Drosophila development and suggest that one outcome is to hold developing muscle cells in a state with differentiation genes poised to be expressed. PMID:17702578

  1. Pelvic floor muscle strength and body self-perception among Brazilian pregnant women.

    PubMed

    Sacomori, Cinara; Cardoso, Fernando Luiz; Vanderlinde, Cristiane

    2010-12-01

    To examine the relationship between pelvic floor muscle strength and body self-perception variables in pregnant women; and, more specifically, to determine the influence of the number of pregnancies (primigravidas vs multigravidas) on the strength of contraction of the pelvic floor muscles and on the body self-perception of pregnant women. Comparative cross-sectional research. Public health centres from Florianópolis, Brazil. Thirty-five pregnant women (18 primigravidas, 17 multigravidas) with a mean age of 25.5 (standard deviation 5.7) years. Pelvic floor strength measured through manual palpation, and body self-perception using the Questionnaire of Corporeality and Human Sexuality. Pelvic floor muscle strength was positively correlated with schooling [rho (ρ)=0.496] and body self-perception variables: finding the body beautiful (ρ=0.476), finding the body sexy (ρ=0.520), feeling that others find them sexy (ρ=0.364), finding the body proportional (ρ=0.412), touching the body generally (ρ=0.554) and recognising the smell of the body (ρ=0.454). Primigravidas found their bodies more beautiful and were more satisfied with their bodies. On a scale of 0 to 6, multigravid participants expressed a greater wish than primigravid participants to be thinner (median difference 2, 95% confidence interval 0-3, P=0.03). Pelvic floor strength did not differ between groups. The results suggest a relationship between pelvic floor muscle strength and body self-perception. Professionals involved in women's health may have a role in helping their patients to understand their bodies. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  2. CL316,243, a β3-adrenergic receptor agonist, induces muscle hypertrophy and increased strength.

    PubMed

    Puzzo, Daniela; Raiteri, Roberto; Castaldo, Clotilde; Capasso, Raffaele; Pagano, Ester; Tedesco, Mariateresa; Gulisano, Walter; Drozd, Lisaveta; Lippiello, Pellegrino; Palmeri, Agostino; Scotto, Pietro; Miniaci, Maria Concetta

    2016-11-22

    Studies in vitro have demonstrated that β3-adrenergic receptors (β3-ARs) regulate protein metabolism in skeletal muscle by promoting protein synthesis and inhibiting protein degradation. In this study, we evaluated whether activation of β3-ARs by the selective agonist CL316,243 modifies the functional and structural properties of skeletal muscles of healthy mice. Daily injections of CL316,243 for 15 days resulted in a significant improvement in muscle force production, assessed by grip strength and weight tests, and an increased myofiber cross-sectional area, indicative of muscle hypertrophy. In addition, atomic force microscopy revealed a significant effect of CL316,243 on the transversal stiffness of isolated muscle fibers. Interestingly, the expression level of mammalian target of rapamycin (mTOR) downstream targets and neuronal nitric oxide synthase (NOS) was also found to be enhanced in tibialis anterior and soleus muscles of CL316,243 treated mice, in accordance with previous data linking β3-ARs to mTOR and NOS signaling pathways. In conclusion, our data suggest that CL316,243 systemic administration might be a novel therapeutic strategy worthy of further investigations in conditions of muscle wasting and weakness associated with aging and muscular diseases.

  3. Effects of trunk stabilization exercise on the local muscle activity and balance ability of normal subjects.

    PubMed

    Cha, Hyun Gyu

    2018-06-01

    [Purpose] The purpose of this study was to investigate the effects of trunk stabilization exercise on the transvers abdominalis (TA) and internal oblique (IO) muscle activity and balance ability of normal subjects. [Subjects and Methods] Forty healthy male subjects without orthopedic history of the lower extremity were selected for the present study. The experimental group received a hollowing exercise, curl-up and bridging exercise. The control group received a pelvic tilting exercise in the sitting position for the same period of time. [Results] Significant differences in the post-training gains in Balance index, TA, IO were observed between the experimental group and the control group. [Conclusion] The trunk stabilization exercise improved the balance ability and increased the activity of the TA and IO muscle.

  4. Investigating the effectiveness of postural muscle electrostimulation and static posturography feedback exercises in elders with balance disorder.

    PubMed

    Alptekin, Kerem; Karan, Ayse; Dıracoglu, Demirhan; Yildiz, Aysel; Baskent, Akin; Eskiyurt, Nurten

    2016-01-01

    Deterioration associated with aging in the erect posture and balance to change the location of the center increased the rate of fall in older age is one of the reasons. Loss of muscle strength is one of the major factors affecting the posture. In this prospective, randomized and controlled study, it was aimed to investigate the effectiveness of strengthening postural muscles through electrostimulation or by applying biofeedback exercises with static posturography in patients aged 60 years and over with balance disorder. Patients aged between 60-80 years, who applied to Istanbul Faculty of Medicine Physical Medicine and Rehabilitation Department outpatient clinic and had been diagnosed with balance disorder using the Timed Up and Go (TUG) test, were included. 250 patients were screened, from them 67 patients were enrolled and 57 of them completed the study. Patients were randomized to three groups. The patients in Tetrax® group (TG) group (n:18) participated in a 15-minute exercise with Tetrax® which consisted of 15 minutes exercise session 3 times weekly for 4 weeks. The patients in EG group (n:19) received an electrostimulation program of postural muscles of 40 minutes per session 3 times weekly for 4 weeks. Patients in the control group (n:20) did 6-week balance exercises which were performed by other groups as well. 48 out of 57 patients attended the 6th-month control. As determinants of balance status Timed Up and Go Test (TUG), Berg Balance Scale (BBS) and Fall Index measured by Tetrax® were calculated at baseline, 1-month and 6-month follw up assesments. The patient's quality of life was assesed by Turkish version of World Health Organisation Quality of Life Questionnaire in Older Adults (WHOQOL-OLD.TR) at baseline and 6-month follow up assesments. TUG values in both EG and TG decreased significantly between baseline assesment and 1-month (mean differences for TG: -4,00 ± 1,309 and EG -2,588 ± 1,839 p= 0,002 for the each of groups) and baseline assesment

  5. Low skeletal muscle mass is associated with poor structural parameters of bone and impaired balance in elderly men--the MINOS study.

    PubMed

    Szulc, Pawel; Beck, Tom J; Marchand, François; Delmas, Pierre D

    2005-05-01

    In 796 men, 50-85 years of age, decreased relative skeletal muscle mass index was associated with narrower bones, thinner cortices, and a consequent decreased bending strength (lower section modulus), as well as with impaired balance and an increased risk of falls. In men, appendicular skeletal muscle mass (ASM) is correlated positively with BMC and areal BMD (aBMD). In elderly men, low muscle mass and strength (sarcopenia) is associated with difficulties in daily living activities. The aim of this study was to evaluate if ASM is correlated with bone size, mechanical properties of bones, balance, and risk of falls in elderly men. This study used 796 men, 50-85 years of age, belonging to the MINOS cohort. Lifestyle factors were evaluated by standardized questionnaires. Estimates of mechanical bone properties were derived from aBMD measured by DXA. ASM was estimated by DXA. The relative skeletal muscle mass index (RASM) was calculated as ASM/(body height)(2.3). After adjustment for age, body size, tobacco smoking, professional physical activity, and 17beta-estradiol concentration, RASM was correlated positively with BMC, aBMD, external diameter, and cortical thickness (r = 0.17-0.34, p < 0.0001) but not with volumetric BMD. Consequently, RASM was correlated with section modulus (r = 0.29-0.39, p < 0.0001). Men in the lowest quartile of RASM had section modulus of femoral neck and distal radius lower by 12-18% in comparison with men in the highest quartile of RASM. In contrast, bone width was not correlated with fat mass, reflecting the load of body weight (except for L(3)), which suggests that the muscular strain may exert a direct stimulatory effect on periosteal apposition. After adjustment for confounding variables, a decrease in RASM was associated with increased risk of falls and of inability to accomplish clinical tests of muscle strength, static balance, and dynamic balance (odds ratio per 1 SD decrease in RASM, 1.31-2.23; p < 0.05-0.001). In elderly men

  6. Effect of strength and speed of torque development on balance recovery with the ankle strategy.

    PubMed

    Robinovitch, Stephen N; Heller, Britta; Lui, Andrew; Cortez, Jeffrey

    2002-08-01

    In the event of an unexpected disturbance to balance, the ability to recover a stable upright stance should depend not only on the magnitude of torque that can be generated by contraction of muscles spanning the lower extremity joints but also on how quickly these torques can be developed. In the present study, we used a combination of experimental and mathematical models of balance recovery by sway (feet in place responses) to test this hypothesis. Twenty-three young subjects participated in experiments in which they were supported in an inclined standing position by a horizontal tether and instructed to recover balance by contracting only their ankle muscles. The maximum lean angle where they could recover balance without release of the tether (static recovery limit) averaged 14.9 +/- 1.4 degrees (mean +/- SD). The maximum initial lean angle where they could recover balance after the tether was unexpectedly released and the ankles were initially relaxed (dynamic recovery limit) averaged 5.9 +/- 1.1 degrees, or 60 +/- 11% smaller than the static recovery limit. Peak ankle torque did not differ significantly between the two conditions (and averaged 116 +/- 32 Nm), indicating the strong effect on recovery ability of latencies in the onset and subsequent rates of torque generation (which averaged 99 +/- 13 ms and 372 +/- 267 N. m/s, respectively). Additional experiments indicated that dynamic recovery limits increased 11 +/- 14% with increases in the baseline ankle torques prior to release (from an average value of 31 +/- 18 to 54 +/- 24 N. m). These trends are in agreement with predictions from a computer simulation based on an inverted pendulum model, which illustrate the specific combinations of baseline ankle torque, rate of torque generation, and peak ankle torque that are required to attain target recovery limits.

  7. Effect of Acute Effort on Isometric Strength and Body Balance: Trained vs. Untrained Paradigm.

    PubMed

    Sterkowicz, Stanisław; Jaworski, Janusz; Lech, Grzegorz; Pałka, Tomasz; Sterkowicz-Przybycień, Katarzyna; Bujas, Przemysław; Pięta, Paweł; Mościński, Zenon

    2016-01-01

    Years of training in competitive sports leads to human body adaptation to a specific type of exercise. In judo bouts, maintaining hand grip on an opponent's clothes and postural balance is essential for the effective technical and tactical actions. This study compares changes after maximal anaerobic exercise among judo athletes and untrained subjects regarding 1) maximum isometric handgrip strength (HGSmax) and accuracy at the perceived 50% maximum handgrip force (1/2HGSmax) and 2) the balance of 13 judo athletes at national (n = 8) and international (n = 5) competitive levels and 19 untrained university students. The groups did not differ in age, body height, and weight. Body mass index (BMI) and body composition (JAWON) were evaluated. The Wingate Anaerobic Test (WAnT, Monark 875E) measured recommended anaerobic capacity indices. Hand grip strength (Takei dynamometer) and balance (biplate balance platform) were measured before warm-up (T1), before the WAnT test (T2), and after (T3). Parametric or non-parametric tests were performed after verifying the variable distribution assumption. Judoists had higher BMI and fat-free mass index (FFMI) than the students. The athletes also showed higher relative total work and relative peak power and lower levels of lactic acid. The difference in judoists between HGSmax at T1 and HGSmax at T3 was statistically significant. Before warm-up (T1), athletes showed higher strength (more divergent from the calculated ½HGSmax value) compared to students. Substantial fatigue after the WAnT test significantly deteriorated the body stability indices, which were significantly better in judo athletes at all time points. The findings suggest specific body adaptations in judoists, especially for body composition, anaerobic energy system efficiency, and postural balance. These characteristics could be trained for specifically by judo athletes to meet the time-motion and anaerobic demands of contemporary bouts.

  8. Effect of Acute Effort on Isometric Strength and Body Balance: Trained vs. Untrained Paradigm

    PubMed Central

    Sterkowicz, Stanisław; Jaworski, Janusz; Lech, Grzegorz; Pałka, Tomasz; Sterkowicz-Przybycień, Katarzyna; Bujas, Przemysław; Pięta, Paweł; Mościński, Zenon

    2016-01-01

    Years of training in competitive sports leads to human body adaptation to a specific type of exercise. In judo bouts, maintaining hand grip on an opponent’s clothes and postural balance is essential for the effective technical and tactical actions. This study compares changes after maximal anaerobic exercise among judo athletes and untrained subjects regarding 1) maximum isometric handgrip strength (HGSmax) and accuracy at the perceived 50% maximum handgrip force (1/2HGSmax) and 2) the balance of 13 judo athletes at national (n = 8) and international (n = 5) competitive levels and 19 untrained university students. The groups did not differ in age, body height, and weight. Body mass index (BMI) and body composition (JAWON) were evaluated. The Wingate Anaerobic Test (WAnT, Monark 875E) measured recommended anaerobic capacity indices. Hand grip strength (Takei dynamometer) and balance (biplate balance platform) were measured before warm-up (T1), before the WAnT test (T2), and after (T3). Parametric or non-parametric tests were performed after verifying the variable distribution assumption. Judoists had higher BMI and fat-free mass index (FFMI) than the students. The athletes also showed higher relative total work and relative peak power and lower levels of lactic acid. The difference in judoists between HGSmax at T1 and HGSmax at T3 was statistically significant. Before warm-up (T1), athletes showed higher strength (more divergent from the calculated ½HGSmax value) compared to students. Substantial fatigue after the WAnT test significantly deteriorated the body stability indices, which were significantly better in judo athletes at all time points. The findings suggest specific body adaptations in judoists, especially for body composition, anaerobic energy system efficiency, and postural balance. These characteristics could be trained for specifically by judo athletes to meet the time-motion and anaerobic demands of contemporary bouts. PMID:27218258

  9. Tension in Skinned Frog Muscle Fibers in Solutions of Varying Ionic Strength and Neutral Salt Composition

    PubMed Central

    Gordon, A. M.; Godt, R. E.; Donaldson, S. K. B.; Harris, C. E.

    1973-01-01

    The maximal calcium-activated isometric tension produced by a skinned frog single muscle fiber falls off as the ionic strength of the solution bathing this fiber is elevated declining to zero near 0.5 M as the ionic strength is varied using KCl. When other neutral salts are used, the tension always declines at high ionic strength, but there is some difference between the various neutral salts used. The anions and cations can be ordered in terms of their ability to inhibit the maximal calcium-activated tension. The order of increasing inhibition of tension (decreasing tension) at high ionic strength for anions is propionate- ≃ SO4 -- < Cl- < Br-. The order of increasing inhibition of calcium-activated tension for cations is K+ ≃ Na+ ≃ TMA+ < TEA+ < TPrA+ < TBuA+. The decline of maximal calcium-activated isometric tension with elevated salt concentration (ionic strength) can quantitatively explain the decline of isometric tetanic tension of a frog muscle fiber bathed in a hypertonic solution if one assumes that the internal ionic strength of a muscle fiber in normal Ringer's solution is 0.14–0.17 M. There is an increase in the base-line tension of a skinned muscle fiber bathed in a relaxing solution (no added calcium and 3 mM EGTA) of low ionic strength. This tension, which has no correlate in the intact fiber in hypotonic solutions, appears to be a noncalcium-activated tension and correlates more with a declining ionic strength than with small changes in [MgATP], [Mg], pH buffer, or [EGTA]. It is dependent upon the specific neutral salts used with cations being ordered in increasing inhibition of this noncalcium-activated tension (decreasing tension) as TPrA+ < TMA+ < K+ ≃ Na+. Measurements of potentials inside these skinned muscle fibers bathed in relaxing solutions produced occasional small positive values (<6 mV) which were not significantly different from zero. PMID:4543066

  10. Targeting DMPK with Antisense Oligonucleotide Improves Muscle Strength in Myotonic Dystrophy Type 1 Mice.

    PubMed

    Jauvin, Dominic; Chrétien, Jessina; Pandey, Sanjay K; Martineau, Laurie; Revillod, Lucille; Bassez, Guillaume; Lachon, Aline; MacLeod, A Robert; Gourdon, Geneviève; Wheeler, Thurman M; Thornton, Charles A; Bennett, C Frank; Puymirat, Jack

    2017-06-16

    Myotonic dystrophy type 1 (DM1), a dominant hereditary muscular dystrophy, is caused by an abnormal expansion of a (CTG) n trinucleotide repeat in the 3' UTR of the human dystrophia myotonica protein kinase (DMPK) gene. As a consequence, mutant transcripts containing expanded CUG repeats are retained in nuclear foci and alter the function of splicing regulatory factors members of the MBNL and CELF families, resulting in alternative splicing misregulation of specific transcripts in affected DM1 tissues. In the present study, we treated DMSXL mice systemically with a 2'-4'-constrained, ethyl-modified (ISIS 486178) antisense oligonucleotide (ASO) targeted to the 3' UTR of the DMPK gene, which led to a 70% reduction in CUG exp RNA abundance and foci in different skeletal muscles and a 30% reduction in the heart. Furthermore, treatment with ISIS 486178 ASO improved body weight, muscle strength, and muscle histology, whereas no overt toxicity was detected. This is evidence that the reduction of CUG exp RNA improves muscle strength in DM1, suggesting that muscle weakness in DM1 patients may be improved following elimination of toxic RNAs. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Test-Retest Reliability of Innovated Strength Tests for Hip Muscles

    PubMed Central

    Meyer, Christophe; Corten, Kristoff; Wesseling, Mariska; Peers, Koen; Simon, Jean-Pierre; Jonkers, Ilse; Desloovere, Kaat

    2013-01-01

    The burden of hip muscles weakness and its relation to other impairments has been well documented. It is therefore a pre-requisite to have a reliable method for clinical assessment of hip muscles function allowing the design and implementation of a proper strengthening program. Motor-driven dynamometry has been widely accepted as the gold-standard for lower limb muscle strength assessment but is mainly related to the knee joint. Studies focusing on the hip joint are less exhaustive and somewhat discrepant with regard to optimal participants position, consequently influencing outcome measures. Thus, we aimed to develop a standardized test setup for the assessment of hip muscles strength, i.e. flexors/extensors and abductors/adductors, with improved participant stability and to define its psychometric characteristics. Eighteen participants performed unilateral isokinetic and isometric contractions of the hip muscles in the sagittal and coronal plane at two separate occasions. Peak torque and normalized peak torque were measured for each contraction. Relative and absolute measures of reliability were calculated using the intraclass correlation coefficient and standard error of measurement, respectively. Results from this study revealed higher levels of between-day reliability of isokinetic/isometric hip abduction/flexion peak torque compared to existing literature. The least reliable measures were found for hip extension and adduction, which could be explained by a less efficient stabilization technique. Our study additionally provided a first set of reference normalized data which can be used in future research. PMID:24260550

  12. PGC-1α is important for maintaining the balance of muscle mass and myofiber types in unloaded muscle atrophy

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoping; He, Jian; Wang, Fei; Zhang, Peng; Liu, Hongju; Li, Wenjiong

    2016-07-01

    maintaining the balance of muscle mass and myofiber type MHCs in unloaded muscle atrophy via suppressing Smad3 activation. This report may prompt a hopeful therapeutic strategy for maintaining muscle mass and fiber type composition in disused muscle atrophies such as space weightlessness- or immobilization-induced muscle atrophy. Acknowledgments This work was supported by the Natural Sciences Foundation of China (31171144, 81272177 and 31171148), the State Key Laboratory Grant of Space Medicine Fundamentals and Application (SMFA13A01), and the National Key Laboratory Grant of Human Factors Engineering (SYFD140051801).

  13. Effects of different heel-raise-lower exercise interventions on the strength of plantarflexion, balance, and gait parameters in stroke survivors.

    PubMed

    Lee, Seung-Mi; Cynn, Heon-Seock; Yoon, Tae-Lim; Lee, Ji-Hyun

    2017-09-01

    The objective of this study was to investigate the effects of Heel-Raise-Lower Exercise (HRLE) interventions on the strength of plantarflexion, balance, and gait parameters in people with stroke. Specifically, this study compared the two different HRLEs to identify whether heels raise-lower with forefoot on a block (HRB) is more effective or ineffective to enhance strength and functional capacities than heels raise-lower on a level floor (HRL) exercise in people with stroke. Repetitive heel raise-lower is a common exercise for improving the strength and power of ankle plantarflexors. It is a simple movement, requires no equipment, and can be performed at home. Each group of 10 people with stroke was given either HRB training or HRL training. The subjects performed the exercise 100 times per day, 5 days per week for 6 weeks. The strength of plantarflexors, static/dynamic balance, and gait parameters were measured using the manual muscle test (MMT), a Biodex Balance System (BBS) SD, and the GAITRite system. After 6 weeks of treatment, there were significant increases in the plantarflexors strength in both groups: by 34% in the HRB group and by 21% in the HRL group. Static and dynamic balance and gait speed also increased significantly in both groups. However, cadence, the paretic side single limb support period (SLSP), paretic side step length, and paretic side stride length significantly increased only in the HRB group. The HRB improved significantly the plantar flexor strength of the paretic side, gait speed, and cadence compared to the HRL.

  14. Efficacy of Nintendo Wii training on mechanical leg muscle function and postural balance in community-dwelling older adults: a randomized controlled trial.

    PubMed

    Jorgensen, Martin G; Laessoe, Uffe; Hendriksen, Carsten; Nielsen, Ole Bruno Faurholt; Aagaard, Per

    2013-07-01

    Older adults show increased risk of falling and major risk factors include impaired lower extremity muscle strength and postural balance. However, the potential positive effect of biofeedback-based Nintendo Wii training on muscle strength and postural balance in older adults is unknown. This randomized controlled trial examined postural balance and muscle strength in community-dwelling older adults (75±6 years) pre- and post-10 weeks of biofeedback-based Nintendo Wii training (WII, n = 28) or daily use of ethylene vinyl acetate copolymer insoles (controls [CON], n = 30). Primary end points were maximal muscle strength (maximal voluntary contraction) and center of pressure velocity moment during bilateral static stance. Intention-to-treat analysis with adjustment for age, sex, and baseline level showed that the WII group had higher maximal voluntary contraction strength (18%) than the control group at follow up (between-group difference = 269 N, 95% CI = 122; 416, and p = .001). In contrast, the center of pressure velocity moment did not differ (1%) between WII and CON at follow-up (between-group difference = 0.23 mm(2)/s, 95% CI = -4.1; 4.6, and p = .92). For secondary end points, pre-to-post changes favoring the WII group were evident in the rate of force development (p = .03), Timed Up and Go test (p = .01), short Falls Efficacy Scale-International (p = .03), and 30-second repeated Chair Stand Test (p = .01). Finally, participants rated the Wii training highly motivating at 5 and 10 weeks into the intervention. Biofeedback-based Wii training led to marked improvements in maximal leg muscle strength (maximal voluntary contraction; rate of force development) and overall functional performance in community-dwelling older adults. Unexpectedly, static bilateral postural balance remained unaltered with Wii training. The high level of participant motivation suggests that biofeedback-based Wii exercise may ensure a high degree of compliance to home- and/or community

  15. Influence of recreational activity and muscle strength on ulnar bending stiffness in men

    NASA Technical Reports Server (NTRS)

    Myburgh, K. H.; Charette, S.; Zhou, L.; Steele, C. R.; Arnaud, S.; Marcus, R.

    1993-01-01

    Bone bending stiffness (modulus of elasticity [E] x moment of inertia [I]), a measure of bone strength, is related to its mineral content (BMC) and geometry and may be influenced by exercise. We evaluated the relationship of habitual recreational exercise and muscle strength to ulnar EI, width, and BMC in 51 healthy men, 28-61 yr of age. BMC and width were measured by single photon absorptiometry and EI by mechanical resistance tissue analysis. Maximum biceps strength was determined dynamically (1-RM) and grip strength isometrically. Subjects were classified as sedentary (S) (N = 13), moderately (M) (N = 18), or highly active (H) (N = 20) and exercised 0.2 +/- 0.2; 2.2 +/- 1.3; and 6.8 +/- 2.3 h.wk-1 (P < 0.001). H had greater biceps (P < 0.0005) and grip strength (P < 0.05), ulnar BMC (P < 0.05), and ulnar EI (P = 0.01) than M or S, who were similar. Amount of activity correlated with grip and biceps strength (r = 0.47 and 0.49; P < 0.001), but not with bone measurements, whereas muscle strength correlated with both EI and BMC (r = 0.40-0.52, P < 0.005). EI also correlated significantly with both BMC and ulnar width (P < 0.0001). Ulnar width and biceps strength were the only independent predictors of EI (r2 = 0.67, P < 0.0001). We conclude that levels of physical activity sufficient to increase arm strength influence ulnar bending stiffness.

  16. Do Psychosocial Factors Predict Muscle Strength, Pain, or Physical Performance in Patients With Knee Osteoarthritis?

    PubMed

    Baert, Isabel A C; Meeus, Mira; Mahmoudian, Armaghan; Luyten, Frank P; Nijs, Jo; Verschueren, Sabine M P

    2017-09-01

    The aim of this study was to examine the relationship of psychosocial factors, namely, pain catastrophizing, kinesiophobia, and maladaptive coping strategies, with muscle strength, pain, and physical performance in patients with knee osteoarthritis (OA)-related symptoms. A total of 109 women (64 with knee OA-related symptoms) with a mean age of 65.4 years (49-81 years) were recruited for this study. Psychosocial factors were quantified by the Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, and Pain Coping Inventory. Clinical features were assessed using isometric and isokinetic knee muscle strength measurements, visual analog scale, Western Ontario and McMaster Universities Osteoarthritis Index, and functional tests. Associations were examined using correlation and regression analysis. In knee OA patients, pain catastrophizing, kinesiophobia, and coping strategy explained a significant proportion of the variability in isometric knee extension and flexion strength (6.3%-9.2%), accounting for more overall variability than some demographic and medical status variables combined. Psychosocial factors were not significant independent predictors of isokinetic strength, knee pain, or physical performance. In understanding clinical features related to knee OA, such as muscle weakness, pain catastrophizing, kinesiophobia, and coping strategy might offer something additional beyond what might be explained by traditional factors, underscoring the importance of a biopsychosocial approach in knee OA management. Further research on individual patient characteristics that mediate the effects of psychosocial factors is, however, required in order to create opportunities for more targeted, personalized treatment for knee OA.

  17. Improvement of isometric dorsiflexion protocol for assessment of tibialis anterior muscle strength.

    PubMed

    Siddiqi, Ariba; Arjunan, Sridhar P; Kumar, Dinesh

    2015-01-01

    It is important to accurately estimate the electromyogram (EMG)/force relationship of triceps surae (TS) muscle for detecting strength deficit of tibalis anterior (TA) muscle. In literature, the protocol for recording EMG and force of dorsiflexion have been described, and the necessity for immobilizing the ankle has been explained. However, there is a significant variability of the results among researchers even though they report the fixation of the ankle. We have determined that toe extension can cause significant variation in the dorsiflexion force and EMG of TS and this can occur despite following the current guidelines which require immobilizing the ankle. The results also show that there was a large increase in the variability of the force and the RMS of EMG of TS when the toes were not strapped compared with when they were strapped. Thus, with the current guidelines, where there are no instructions regarding the necessity of strapping the toes, the EMG/force relationship of TS could be incorrect and give an inaccurate assessment of the dorsiflexor TA strength. In summary, •Current methodology to estimate the dorsiflexor TA strength with respect to the TS activity, emphasizing on ankle immobilization is insufficient to prevent large variability in the measurements.•Toe extension during dorsiflexion was found to be one source of variability in estimating the TA strength.•It is recommended that guidelines for recording force and EMG from TA and TS muscles should require the strapping of the toes along with the need for immobilizing the ankle.

  18. Balance decrements are associated with age-related muscle property changes.

    PubMed

    Hasson, Christopher J; van Emmerik, Richard E A; Caldwell, Graham E

    2014-08-01

    In this study, a comprehensive evaluation of static and dynamic balance abilities was performed in young and older adults and regression analysis was used to test whether age-related variations in individual ankle muscle mechanical properties could explain differences in balance performance. The mechanical properties included estimates of the maximal isometric force capability, force-length, force-velocity, and series elastic properties of the dorsiflexors and individual plantarflexor muscles (gastrocnemius and soleus). As expected, the older adults performed more poorly on most balance tasks. Muscular maximal isometric force, optimal fiber length, tendon slack length, and velocity-dependent force capabilities accounted for up to 60% of the age-related variation in performance on the static and dynamic balance tests. In general, the plantarflexors had a stronger predictive role than the dorsiflexors. Plantarflexor stiffness was strongly related to general balance performance, particularly in quiet stance; but this effect did not depend on age. Together, these results suggest that age-related differences in balance performance are explained in part by alterations in muscular mechanical properties.

  19. Muscle volume, strength, endurance, and exercise loads during 6-month missions in space.

    PubMed

    Gopalakrishnan, Raghavan; Genc, Kerim O; Rice, Andrea J; Lee, Stuart M C; Evans, Harlan J; Maender, Christian C; Ilaslan, Hakan; Cavanagh, Peter R

    2010-02-01

    Decrements in muscular strength during long-duration missions in space could be mission-critical during construction and exploration activities. The purpose of this study was to quantify changes in muscle volume, strength, and endurance of crewmembers on the International Space Station (ISS) in the context of new measurements of loading during exercise countermeasures. Strength and muscle volumes were measured from four male ISS crewmembers (49.5 +/- 4.7 yr, 179.3 +/- 7.1 cm, 85.2 +/- 10.4 kg) before and after long-duration spaceflight (181 +/- 15 d). Preflight and in-flight measurements of forces between foot and shoe allowed comparisons of loading from 1-g exercise and exercise countermeasures on ISS. Muscle volume change was greater in the calf (-10 to 16%) than the thigh (-4% to -7%), but there was no change in the upper arm (+0.4 to -0.8%). Isometric and isokinetic strength changes at the knee (range -10.4 to -24.1%), ankle (range -4 to -22.3%), and elbow (range -7.5 to -16.7%) were observed. Although there was an overall postflight decline in total work (-14%) during the endurance test, an increase in postflight resistance to fatigue was observed. The peak in-shoe forces during running and cycling on ISS were approximately 46% and 50% lower compared to 1-g values. Muscle volume and strength were decreased in the lower extremities of crewmembers during long-duration spaceflight on ISS despite the use of exercise countermeasures. in-flight countermeasures were insufficient to replicate the daily mechanical loading experienced by the crewmembers before flight. Future exercise protocols need careful assessment both in terms of intensity and duration to maximize the "dose" of exercise and to increase loads compared to the measured levels.

  20. Aerobic exercise and respiratory muscle strength in patients with cystic fibrosis.

    PubMed

    Dassios, Theodore; Katelari, Anna; Doudounakis, Stavros; Dimitriou, Gabriel

    2013-05-01

    The beneficial role of exercise in maintaining health in patients with cystic fibrosis (CF) is well described. Few data exist on the effect of exercise on respiratory muscle function in patients with CF. Our objective was to compare respiratory muscle function indices in CF patients that regularly exercise with those CF patients that do not. This cross-sectional study assessed nutrition, pulmonary function and respiratory muscle function in 37 CF patients that undertook regular aerobic exercise and in a control group matched for age and gender which consisted of 44 CF patients that did not undertake regular exercise. Respiratory muscle function in CF was assessed by maximal inspiratory pressure (Pimax), maximal expiratory pressure (Pemax) and pressure-time index of the respiratory muscles (PTImus). Median Pimax and Pemax were significantly higher in the exercise group compared to the control group (92 vs. 63 cm H2O and 94 vs. 64 cm H2O respectively). PTImus was significantly lower in the exercise group compared to the control group (0.089 vs. 0.121). Upper arm muscle area (UAMA) and mid-arm muscle circumference were significantly increased in the exercise group compared to the control group (2608 vs. 2178 mm2 and 23 vs. 21 cm respectively). UAMA was significantly related to Pimax in the exercising group. These results suggest that CF patients that undertake regular aerobic exercise maintain higher indices of respiratory muscle strength and lower PTImus values, while increased UAMA values in exercising patients highlight the importance of muscular competence in respiratory muscle function in this population. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Quantitative muscle strength testing: a comparison of job strength requirements and actual worker strength among military technicians.

    PubMed

    Pedersen, D M; Clark, J A; Johns, R E; White, G L; Hoffman, S

    1989-01-01

    In this study the authors investigate the percentage of mismatch between job demands and worker physical capacity in Utah National Guard mechanics. This population had demonstrated a higher incidence of low back trouble than other job descriptions reviewed. The authors utilized onsite still and videotape photography and a computerized biomechanical strength prediction model to assess loads on the lumbosacral spine due to various job tasks. Job demands were then compared to the actual physical capacity of the individual workers based on static strength testing in job-related positions. A load cell on the testing apparatus entered the force generated into a computer which averaged the force of the last three seconds of a five-second lift. It was determined that as much as a 38% mismatch existed within this population for some job tasks which these workers were exposed to. Suggestions for preventing job-related low back cumulative trauma disorders are presented, including: engineering redesign, worker selection programs, work hardening, and others.

  2. Effects of specific muscle imbalance improvement training on the balance ability in elite fencers.

    PubMed

    Kim, Taewhan; Kil, Sekee; Chung, Jinwook; Moon, Jeheon; Oh, Eunyoung

    2015-05-01

    [Purpose] The lunge Motion that occurs frequently in fencing training and matches results in imbalance of the upper and lower limbs muscles. This research focuses on the improvement of the imbalance that occurs in the national team fencers of the Republic of Korea through specific muscle imbalance improvement training. [Subjects] The subjects of this research were limited to right-handed male fencers. Nine male, right-handed national fencing athletes were selected for this study (4 epee, 5 sabre; age 28.2 ± 2.2 years; height 182.3 ± 4.0 cm; weight 76.5 ± 8.2 kg; experience 12.4 ± 3.0 years). [Methods] The specific muscle imbalance improvement training program was performed for 12 weeks and Pre-Post tests were to evaluate its effect on the experimental group. Measurements comprised anthropometry, test of balance, and movement analysis. [Results] After the training program, mediolateral sway of the nondominant lower limb and the balance scale showed statistically significant improvement. [Conclusion] The specific muscle imbalance improvement training program used in this research was proven to be effective for improving the muscle imbalance of elite fencers.

  3. Excess Coenzyme A Reduces Skeletal Muscle Performance and Strength in Mice Overexpressing Human PANK2

    PubMed Central

    Corbin, Deborah R.; Rehg, Jerold E.; Shepherd, Danielle L.; Stoilov, Peter; Percifield, Ryan J.; Horner, Linda; Frase, Sharon; Zhang, Yong-Mei; Rock, Charles O.; Hollander, John M.; Jackowski, Suzanne; Leonardi, Roberta

    2017-01-01

    Coenzyme A (CoA) is a cofactor that is central to energy metabolism and CoA synthesis is controlled by the enzyme pantothenate kinase (PanK). A transgenic mouse strain expressing human PANK2 was derived to determine the physiological impact of PANK overexpression and elevated CoA levels. The Tg(PANK2) mice expressed high levels of the transgene in skeletal muscle and heart; however, CoA was substantially elevated only in skeletal muscle, possibly associated with the comparatively low endogenous levels of acetyl-CoA, a potent feedback inhibitor of PANK2. Tg(PANK2) mice were smaller, had less skeletal muscle mass and displayed significantly impaired exercise tolerance and grip strength. Skeletal myofibers were characterized by centralized nuclei and aberrant mitochondria. Both the content of fully assembled complex I of the electron transport chain and ATP levels were reduced, while markers of oxidative stress were elevated in Tg(PANK2) skeletal muscle. These abnormalities were not detected in the Tg(PANK2) heart muscle, with the exception of spotty loss of cristae organization in the mitochondria. The data demonstrate that excessively high CoA may be detrimental to skeletal muscle function. PMID:28189602

  4. Association of Increased Serum Ferritin With Impaired Muscle Strength/Quality in Hemodialysis Patients.

    PubMed

    Nakagawa, Chie; Inaba, Masaaki; Ishimura, Eiji; Yamakawa, Tomoyuki; Shoji, Shigeichi; Okuno, Senji

    2016-07-01

    We reported previously that muscle quality and muscle strength provide clinically relevant predictors for better survival in hemodialysis patients. Iron overload might impair muscle function by its accumulation in muscle in such patients. Serum ferritin, a marker for body iron store, was examined for its association with handgrip strength (HGS) and muscle quality which was defined as the ratio of HGS to arm lean mass measured with dual-energy X-ray absorptiometry. In 300 Japanese hemodialysis patients, age, hemodialysis duration, body mass index, and serum albumin were 58.0 ±12.0 (mean ± standard deviation) years, 4.2 (1.8-10.4) (median [25th-75th percentile]) years, 20.4 ± 2.8 kg/m(2), 4.0 ± 0.3 g/dL, respectively. Hemoglobin and hematocrit were 8.9 ± 1.2 g/dL, and 28.8 ± 3.9%, respectively, whereas transferrin saturation and serum ferritin were 29.8 ± 11.0% and 100 (54-172) ng/mL, respectively. Serum ferritin significantly correlated in a positive manner with the total dose of iron orally administered during the previous 6 months (r = 0.185, P = .0013). HGS and muscle quality were 23.1 ± 10.4 kg and 11.6 ± 3.8 kg/kg, respectively. In multivariate analysis to elucidate the factors associated with HGS and muscle quality in 300 hemodialysis patients, which included transferrin saturation and log serum ferritin, in addition to age, gender, hemodialysis duration, the presence/absence of diabetes, body mass index as independent variables, log serum ferritin emerged as a significant and independent factor which associated in a negative fashion with HGS (β = -0.091, P = .0395) and tendency toward negative association with muscle quality (β = -0.100, P = .0754). In summary, the present study demonstrated the significant association of serum ferritin with HGS and muscle quality in hemodialysis patients and thus suggested that we should be careful of iron overload to avoid its possible harmful effect on muscle in such patients. Copyright © 2016 National Kidney

  5. Relationship between muscle strength and fall episodes among the elderly: the Yilan study, Taiwan.

    PubMed

    Yang, Nan-Ping; Hsu, Nai-Wei; Lin, Ching-Heng; Chen, Hsi-Chung; Tsao, Hsuan-Ming; Lo, Su-Shun; Chou, Pesus

    2018-04-13

    Fall episodes are not unusual among community residents, especially the elderly, and lower muscle strength is an important issue to address in order to prevent falls. A community health survey was conducted in a suburban area of Taiwan, and 1067 older adults were selected for enrollment in the present study. All the enrolled subjects had been visited at their homes; the subjects' strength of both hands and muscle mass of both legs were measured and well-established questionnaires were finished by certificated paramedic staffs. The incidence of fall episodes in the previous 1 year in the Yilan elderly population was 15.1%, and the female predominance was significant. A significantly higher prevalence of cataracts was found in group who experienced a fall in the past year (64% vs. 54.9% in the non-fall group). Mild or more severe dementia was much more prevalent in the group who experienced a recent fall (33.8% vs. 25.7% in the non-fall group). The strength of both hands tested as the physical function was 17.6 ± 8.0 kg in the recent fall group, significantly weaker than that in the non-fall group (20.7 ± 8.7 kg). Multivariate regression analysis revealed a greater weekly exercise duration and greater strength of both hands reduced the occurrence of falls among the whole and the female population. The standardized effect sizes of hand grip strength between both groups, not trivial, were 0.29 and 0.37 for the total population and the female subpopulation respectively. Less weekly exercise duration and weaker muscle strength were f ound to be independent risk factors of fall episode(s) in an elderly Taiwanese population, especially in the female sub-population. Muscle strength, measured by average of both hands grip strength, was the most significantly factor of one-year fall episode(s) accessed retrospectively.

  6. A Randomized Trial on the Effect of Bone Tissue on Vibration-induced Muscle Strength Gain and Vibration-induced Reflex Muscle Activity

    PubMed Central

    Cidem, Muharrem; Karacan, İlhan; Diraçoğlu, Demirhan; Yıldız, Aysel; Küçük, Suat Hayri; Uludağ, Murat; Gün, Kerem; Özkaya, Murat; Karamehmetoğlu, Şafak Sahir

    2014-01-01

    Background: Whole-body vibration (WBV) induces reflex muscle activity and leads to increased muscle strength. However, little is known about the physiological mechanisms underlying the effects of whole-body vibration on muscular performance. Tonic vibration reflex is the most commonly cited mechanism to explain the effects of whole-body vibration on muscular performance, although there is no conclusive evidence that tonic vibration reflex occurs. The bone myoregulation reflex is another neurological mechanism used to explain the effects of vibration on muscular performance. Bone myoregulation reflex is defined as a reflex mechanism in which osteocytes exposed to cyclic mechanical loading induce muscle activity. Aims: The aim of this study was to assess whether bone tissue affected vibration-induced reflex muscle activity and vibration-induced muscle strength gain. Study Design: A prospective, randomised, controlled, double-blind, parallel-group clinical trial. Methods: Thirty-four participants were randomised into two groups. High-magnitude whole-body vibration was applied in the exercise group, whereas low-magnitude whole-body vibration exercises were applied in the control group throughout 20 sessions. Hip bone mineral density, isokinetic muscle strength, and plasma sclerostin levels were measured. The surface electromyography data were processed to obtain the Root Mean Squares, which were normalised by maximal voluntarily contraction. Results: In the exercise group, muscle strength increased in the right and left knee flexors (23.9%, p=0.004 and 27.5%, p<0.0001, respectively). However, no significant change was observed in the knee extensor muscle strength. There was no significant change in the knee muscle strength in the control group. The vibration-induced corrected Root Mean Squares of the semitendinosus muscle was decreased by 2.8 times (p=0.005) in the exercise group, whereas there was no change in the control group. Sclerostin index was decreased by 15

  7. A Randomized Trial on the Effect of Bone Tissue on Vibration-induced Muscle Strength Gain and Vibration-induced Reflex Muscle Activity.

    PubMed

    Cidem, Muharrem; Karacan, Ilhan; Diraçoğlu, Demirhan; Yıldız, Aysel; Küçük, Suat Hayri; Uludağ, Murat; Gün, Kerem; Ozkaya, Murat; Karamehmetoğlu, Safak Sahir

    2014-03-01

    Whole-body vibration (WBV) induces reflex muscle activity and leads to increased muscle strength. However, little is known about the physiological mechanisms underlying the effects of whole-body vibration on muscular performance. Tonic vibration reflex is the most commonly cited mechanism to explain the effects of whole-body vibration on muscular performance, although there is no conclusive evidence that tonic vibration reflex occurs. The bone myoregulation reflex is another neurological mechanism used to explain the effects of vibration on muscular performance. Bone myoregulation reflex is defined as a reflex mechanism in which osteocytes exposed to cyclic mechanical loading induce muscle activity. The aim of this study was to assess whether bone tissue affected vibration-induced reflex muscle activity and vibration-induced muscle strength gain. A prospective, randomised, controlled, double-blind, parallel-group clinical trial. Thirty-four participants were randomised into two groups. High-magnitude whole-body vibration was applied in the exercise group, whereas low-magnitude whole-body vibration exercises were applied in the control group throughout 20 sessions. Hip bone mineral density, isokinetic muscle strength, and plasma sclerostin levels were measured. The surface electromyography data were processed to obtain the Root Mean Squares, which were normalised by maximal voluntarily contraction. In the exercise group, muscle strength increased in the right and left knee flexors (23.9%, p=0.004 and 27.5%, p<0.0001, respectively). However, no significant change was observed in the knee extensor muscle strength. There was no significant change in the knee muscle strength in the control group. The vibration-induced corrected Root Mean Squares of the semitendinosus muscle was decreased by 2.8 times (p=0.005) in the exercise group, whereas there was no change in the control group. Sclerostin index was decreased by 15.2% (p=0.031) in the exercise group and increased by

  8. Multimedia-Based Therapy Model for Non-Pharmacological Stroke with Decrease Impaired Muscle Strength

    NASA Astrophysics Data System (ADS)

    Hajar Puji Sejati, Rr; Muhimmah, Izzati; Mahtarami, Affan

    2016-01-01

    Stroke patients who experience a decrease in muscle strength need to do exercises so that they can increase their muscle strength. In order to enable the patient does exercise independently the multimedia-based stroke therapy model is needed. These exercises can be done independently, with supervision of the family member at home. So, we develop prototype of the multimedia-based therapy for the family member so that they can assist patients performing exercises without attending therapy session in hospital. This model was built according to the advices from physiotherapist and a medical rehabilitation doctor. This model has been evaluated through focused group discussion by physiotherapists. And they gave positive responses to this proposed model.

  9. Effects of phosphatidic acid supplementation on muscle thickness and strength in resistance-trained men.

    PubMed

    Gonzalez, Adam M; Sell, Katie M; Ghigiarelli, Jamie J; Kelly, Christopher F; Shone, Edward W; Accetta, Matthew R; Baum, Jamie B; Mangine, Gerald T

    2017-04-01

    The purpose of this study was to investigate the effects of phosphatidic acid (PA) supplementation on muscle thickness and strength following an 8 week supervised resistance-training program. Fifteen resistance trained men (22.8 ± 3.5 years; 80.6 ± 8.7 kg; 178.1 ± 5.6 cm; 14.6% ± 8.8% body fat) were randomly assigned to a group that either consumed 750 mg of PA or a placebo (PL). Testing was carried out before (PRE) and after (POST) training/supplementation for muscle thickness and strength. Muscle thickness of the rectus femoris (RF), vastus lateralis (VL), biceps brachii (BB), and triceps brachii (TB) muscles were measured via ultrasonography, along with 1 repetition maximum (1RM) of squat, deadlift, and bench press. Analysis of covariance (ANCOVA), using PRE values as the covariate, did not reveal any group differences for measures of muscle thickness in the RF (PA: 3.6% ± 5.2%; PL: 3.2% ± 4.2%, p = 0.97), VL (PA: 23.4% ± 18.1%, PL: 12.5% ± 15.4%, p = 0.37), BB (PA: 3.7% ± 6.4%, PL: 9.6% ± 12.4%, p = 0.86), or TB (PA: 15.1% ± 17.9%, PL: 10.7% ± 19.3%, p = 0.79). Likewise, no group differences were observed in changes in squat (PA: 8.4% ± 4.1%, PL: 8.1% ± 4.2%, p = 0.79), deadlift (PA: 10.1% ± 10.1%, PL: 8.9% ± 9.5%, p = 0.66), or bench press (PA: 5.7% ± 5.5%, PL: 5.1% ± 3.0%, p = 0.76) exercises. Collectively, however, all participants experienced significant (p < 0.05) improvements in each measure of muscle thickness and strength. Results of this study suggest that PA supplementation, in combination with a 3 days·week -1 resistance-training program for 8 weeks, did not have a differential effect compared with PL on changes in muscle thickness or 1RM strength.

  10. Optimal mixing rate in linear solvent strength gradient liquid chromatography. Balanced mixing program.

    PubMed

    Blumberg, Leonid M; Desmet, Gert

    2016-12-09

    The mixing rate (R ϕ ) is the temporal rate of increase in the solvent strength in gradient LC. The optimal R ϕ (R ϕ ,Opt ) is the one at which a required peak capacity of gradient LC analysis is obtained in the shortest time. The balanced mixing program is a one where, for better separation of early eluting solutes, the mixing ramp is preceded by a balanced isocratic hold of the duration depending on R ϕ . The improvement in the separation of the earlier eluites due to the balanced programming has been evaluated. The value of R ϕ ,Opt depends on the solvent composition range covered by the mixing ramp and on the column pressure conditions. The R ϕ ,Opt for a column operating at maximum instrumental pressure is different from R ϕ ,Opt for a column operating below the instrumental pressure limit. On the other hand, it has been shown that the difference in the R ϕ ,Opt values under different conditions is not very large so that a single default R ϕ previously recommended for gradient analyses without the isocratic hold also yields a good approximation to the shortest analysis time for all conditions in the balanced analyses. With or without the initial balance isocratic hold, the recommended default R ϕ is about 5%/t 0 (5% increase in the solvent strength per each t 0 -long increment in time) for small-molecule samples, and about an order of magnitude slower (0.5%/t 0 ) for protein samples. A discussion illustrating the use of the optimization criteria employed here for the techniques other than LSS gradient LC is included. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Weight reduction does not induce an undesirable decrease in muscle mass, muscle strength, or physical performance in men with obesity: a pilot study.

    PubMed

    Kim, Bokun; Tsujimoto, Takehiko; So, Rina; Zhao, Xiaoguang; Oh, Sechang; Tanaka, Kiyoji

    2017-12-31

    To date, there have been no reports on whether weight reduction causes decreases in muscle mass, muscle strength, or physical performance that could lead to health problems. Thus, in this pilot study, we investigated the appropriateness of the changes in muscle mass, muscle strength and physical performance after weight reduction. Obese men who completed a weight reduction program to decrease and maintain a body mass index (BMI) of less than 25 kg/m2 for one year were recruited for the study. One year after the completion of a weight reduction program, the participants' muscle mass, muscle strength, and physical performance were compared with those in a reference group composed of individuals whose BMI was less than 25 kg/m2. Whole-body scanning was performed using dual-energy X-ray absorptiometry to analyze muscle mass. Handgrip strength and knee extensor strength were measured to evaluate arm and leg muscle strength, respectively. For physical performance, a jump test was employed. The results showed that the biceps, triceps, subscapular, and suprailiac areas of professional fashion models were significantly thinner than those of women in general (p<.001), and that their waist size was also significantly smaller (p<.001). However, hip circumference showed no significant difference. Body mass index, waist-to-hip ratio, and body fat (%) in professional fashion models were significantly lower than those in women in general (p<.001), while the body density in professional fashion models was significantly greater (p<0.001). Weight reduction participants showed an average reduction in body weight of -16.47%. Normalized arm muscle mass and handgrip strength were significantly greater in the weight reduction group than in the reference group; however, no significant differences were detected between the two groups with respect to the other variables. After one year, there were no significant differences between the two groups. ©2017 The Korean Society for Exercise

  12. Analysis of elbow muscle strength parameters in Brazilian jiu-jitsu practitioners.

    PubMed

    Follmer, Bruno; Dellagrana, Rodolfo André; de Lima, Luis Antonio Pereira; Herzog, Walter; Diefenthaeler, Fernando

    2017-12-01

    Upper-body dynamic and isometric maximum strength are essential components for success in Brazilian jiu-jitsu (BJJ). This study was aimed at analysing strength parameters in the elbow flexor and extensor muscles of BJJ practitioners. Participants (n = 28) performed maximum isometric contractions of elbow flexors and extensors to determine peak torque (PT), rate of force development (RFD), and the torque-angle (T-A) relationship at elbow angles of 45°, 60°, 75°, 90°, 105°, and 120°. Additionally, concentric and eccentric PTs were measured at 1.04 rad·s -1 . Student t-test and ANOVA were performed using α = 0.05. Elbow flexors were stronger isometrically (P < 0.001, ES = 1.23) but weaker concentrically (P < 0.05, ES = 0.54) than extensor muscles, possibly because of the extensive grip disputes and pushing of opponents in BJJ. The T-A relationship had an inverted "U"-shape. Torque differences across elbow angles were moderate (ES = 0.62) for the extensor and large (ES = 0.92) for the flexor muscles. Isometric torque was greatest for elbow angles of 105° and 75° and smallest for 45° and 120° for extensor and flexor muscles, respectively. Elbow flexors had a greater RFD than extensors, regardless of elbow angle. The present study provides comprehensive results for elbow muscle strength in BJJ practitioners.

  13. Effects of winter military training on energy balance, whole-body protein balance, muscle damage, soreness, and physical performance.

    PubMed

    Margolis, Lee M; Murphy, Nancy E; Martini, Svein; Spitz, Marissa G; Thrane, Ingjerd; McGraw, Susan M; Blatny, Janet-Martha; Castellani, John W; Rood, Jennifer C; Young, Andrew J; Montain, Scott J; Gundersen, Yngvar; Pasiakos, Stefan M

    2014-12-01

    Physiological consequences of winter military operations are not well described. This study examined Norwegian soldiers (n = 21 males) participating in a physically demanding winter training program to evaluate whether short-term military training alters energy and whole-body protein balance, muscle damage, soreness, and performance. Energy expenditure (D2(18)O) and intake were measured daily, and postabsorptive whole-body protein turnover ([(15)N]-glycine), muscle damage, soreness, and performance (vertical jump) were assessed at baseline, following a 4-day, military task training phase (MTT) and after a 3-day, 54-km ski march (SKI). Energy intake (kcal·day(-1)) increased (P < 0.01) from (mean ± SD (95% confidence interval)) 3098 ± 236 (2985, 3212) during MTT to 3461 ± 586 (3178, 3743) during SKI, while protein (g·kg(-1)·day(-1)) intake remained constant (MTT, 1.59 ± 0.33 (1.51, 1.66); and SKI, 1.71 ± 0.55 (1.58, 1.85)). Energy expenditure increased (P < 0.05) during SKI (6851 ± 562 (6580, 7122)) compared with MTT (5480 ± 389 (5293, 5668)) and exceeded energy intake. Protein flux, synthesis, and breakdown were all increased (P < 0.05) 24%, 18%, and 27%, respectively, during SKI compared with baseline and MTT. Whole-body protein balance was lower (P < 0.05) during SKI (-1.41 ± 1.11 (-1.98, -0.84) g·kg(-1)·10 h) than MTT and baseline. Muscle damage and soreness increased and performance decreased progressively (P < 0.05). The physiological consequences observed during short-term winter military training provide the basis for future studies to evaluate nutritional strategies that attenuate protein loss and sustain performance during severe energy deficits.

  14. Low intensity vibration of ankle muscles improves balance in elderly persons at high risk of falling

    PubMed Central

    Toosizadeh, Nima; Mohler, Jane

    2018-01-01

    In our study we examined postural performance of young healthy persons (HY), elderly healthy persons (HE), and elderly persons at high risk of falling (FR). Anterio-posterior (AP) and medio-lateral (ML) ankle and hip angular deviations, as well as linear displacements of the center of mass (COM) were assessed in persons standing with eyes either open or closed, while none, and 40 and 30 Hz vibrations were applied bilaterally to the ankle muscle gastrocnemius. During quiet standing with eyes open, balance parameters in FR group differed from those in healthy groups. ML ankle and hip angular deviations, as well as COM linear displacements were noticeably larger in FR group. During quiet standing with eyes closed, all balance parameters in participants of all groups had a clear trend to increase. During standing with eyes open, 40 Hz vibration increased all but one balance parameter within HY group, ankle angular deviations in HE group, but none in FR group. In response to 30 Hz vibration, only ankle angular deviations and COM linear displacements increased in HY group. There were no changes in both elderly groups. During standing with eyes closed, 40 and 30 Hz vibrations did not produce consistent changes in balance parameters in HY and HE groups. In FR persons, 40 Hz vibration did not change balance parameters. However, in FR groups, 30 Hz vibration decreased ankle and hip angular deviations, and COM linear displacements. The major result of the study is a finding that low intensity vibration of ankle muscles makes balance better in elderly persons at high risk of falling. This result is clinically relevant because it suggests that applying mild vibration to ankle muscles while standing and walking might benefit elderly persons, improving their postural performance and reducing a risk of unexpected falls. PMID:29579098

  15. Effect of high-intensity home-based respiratory muscle training on strength of respiratory muscles following a stroke: a protocol for a randomized controlled trial.

    PubMed

    Menezes, Kênia Kiefer Parreiras De; Nascimento, Lucas Rodrigues; Polese, Janaine Cunha; Ada, Louise; Teixeira-Salmela, Luci Fuscaldi

    Respiratory muscle training has shown to increase strength of the respiratory muscles following a stroke. However, low duration and/or intensity of training may be responsible for the small effect size seen and/or absence of carry-over effects to an activity, e.g., walking. Therefore, an investigation of the effects of long-duration, high-intensity respiratory muscle training is warranted. This proposed protocol for a randomized clinical trial will examine the efficacy of high-intensity respiratory muscle training to increase strength and improve activity following a stroke. This study will be a two-arm, prospectively registered, randomized controlled trial, with blinded assessors. Thirty-eight individuals who have suffered a stroke will participate. The experimental group will undertake a 40-min of respiratory muscle training program, seven days/week, for eight weeks in their homes. Training loads will be increased weekly. The control group will undertake a sham respiratory muscle training program with equivalent duration and scheduling of training. The primary outcome will be the strength of the inspiratory muscles, measured as maximal inspiratory pressure. Secondary outcomes will include expiratory muscle strength, inspiratory muscle endurance, dyspnea, respiratory complications, and walking capacity. Outcomes will be collected by a researcher blinded to group allocation at baseline (Week 0), after intervention (Week 8), and one month beyond intervention (Week 12). High-intensity respiratory muscle training may have the potential to optimize the strength of the respiratory muscles following a stroke. If benefits are carried over to activity, the findings may have broader implications, since walking capacity has been shown to predict physical activity and community participation on this population. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

  16. Analysis of the Effect of Menstrual Cycle Phases on Aerobic-Anaerobic Capacity and Muscle Strength

    ERIC Educational Resources Information Center

    Kose, Bereket

    2018-01-01

    The objective of this study is to examine the effect of menstrual cycle phases on aerobic-anaerobic capacity and muscle strength. 10 female kickboxing athletes with an average age of 21.40 ± 2.01 years; average height of 169.60 ± 6.14 cm; average weight of 63.90 ± 5.76 kg and average training age of 7.41 ± 2.10 participated in the study. On the…

  17. Muscle Strength Enhancement Following Home-Based Virtual Cycling Training in Ambulatory Children with Cerebral Palsy

    ERIC Educational Resources Information Center

    Chen, Chia-Ling; Hong, Wei-Hsien; Cheng, Hsin-Yi Kathy; Liaw, Mei-Yun; Chung, Chia-Ying; Chen, Chung-Yao

    2012-01-01

    This study is the first well-designed randomized controlled trial to assess the effects of a novel home-based virtual cycling training (hVCT) program for improving muscle strength in children with spastic cerebral palsy (CP). Twenty-eight ambulatory children with spastic CP aged 6-12 years were randomly assigned to an hVCT group (n = 13) or a…

  18. Muscle strength differ between patients with diabetes and controls following heart surgery.

    PubMed

    Boban, Marko; Barisic, Mijana; Persic, Viktor; Zekanovic, Drazen; Medved, Igor; Zulj, Marinko; Vcev, Aleskandar

    2016-01-01

    The aim of our study was to analyze muscle strength in patients with recent surgical treatment for ischemic and combined ischemic-valvular heart disease, based on existence of diabetes mellitus. Connections existing between muscle strength and patient characteristics or conventional diagnostic tests were analyzed as well. Study prospectively included consecutive patients scheduled for cardiovascular rehabilitation 0-3months after heart surgery. Diagnostics covered drug utilization, anthropometrics, demographics, echocardiography, conventional laboratory, echocardiography, bioelectrical impedance analysis (BIA), and hand grip test (HGT). HGT was analyzed for dominant hand. Patients with diabetes had significantly weaker muscle strength on HGT than controls; 29.4±12.2kg vs. 38.2±14.7kg (p=0.029), respectively. ROC analysis for HGT and existence of diabetes mellitus were significant; ≤40kg had sensitivity of 89.7% (95%CI: 72.6-97.8), specificity 43.7% (31.9-56.0); AUC 0.669 (0.568-0.760); p=0.002. HGT significantly correlated with hematocrit (Rho CC=0.247; p=0.013), whilst other laboratory or echocardiographic parameters were insignificant (all p>0.05). HGT also correlated with body weight (Rho CC=0.510; p<0.001); height (Rho CC=0.632; p<0.001); waist circumference (Rho CC=0.388; p<0.001); waist-to-hip ratio (Rho CC=0.274; p=0.006) and BIA (Rho CC=-0.412; p<0.001). In postoperative recovery of patients with diabetes, muscle strength assessed by HGT is decreased and in relation with nutritional status. Clinically resourceful connections of HGT were also found to hematocrit and utilization of loop diuretics. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Effect of spa physiotherapy on the range of motion and muscle strength in women with gonarthrosis.

    PubMed

    Lizis, Paweł

    2013-01-01

    Degeneration arthritis is a chronic disease of undetermined progressiveness and unknown pathogenesis. It can affect one or more joints. It reveals itself most frequently between 40 - 60 years of age, and affects the lives of professionally active individuals. The aim of the presented study was to assess the impact of a 21-day stay at a rehabilitation facility on the range of motion and muscle strength of the knee in women with gonarthrosis. The study group consisted of 30 women aged 50-74 years diagnosed with degeneration of the knee joint. The average age of the study group was 65.9 ± 7.2 years. Patients remained in the 21-day rehabilitation facility of Rehabilitational Hospital No. 21 in Busko Zdrój SP ZOZ, Poland. We measured with the help of protractor in SFTR range the motion bending and straightening of the knee with an accuracy of 1°. The Lovett strength test was assessed of the ischio-tibial muscles, quadriceps, sartorius--acting on the knee joint of the patient. The study was carried out on the first and the last day of the stay in the rehabilitation facility. There was improvement in the range of flexion and strength of muscles acting on the knee joint of the afflicted women. The study showed that 21-day rehabilitation holiday improved the range and strength of the muscles acting on the knee joint of the afflicted women. This proved that comprehensive rehabilitation improves the function of the knee joint with gonarthrosis, prevents disease progression and is an alternative to drug therapy.

  20. A randomized clinical trial comparing pelvic floor muscle training to a Pilates exercise program for improving pelvic muscle strength.

    PubMed

    Culligan, Patrick J; Scherer, Janet; Dyer, Keisha; Priestley, Jennifer L; Guingon-White, Geri; Delvecchio, Donna; Vangeli, Margi

    2010-04-01

    The purpose of this study is to determine whether a Pilates exercise program and a pelvic floor muscle-training (PFMT) program could provide similar improvements in pelvic muscle strength. Sixty-two women with little or no pelvic floor dysfunction were randomized to Pilates or PFMT. Each group had 24 biweekly 1-h sessions with either a physical therapist or Pilates instructor. Strength was measured via perineometry (cmH(2)O). Two questionnaires--pelvic floor distress inventory (PFDI-20) and pelvic floor impact questionnaire (PFIQ-7)--were also collected. At baseline, the Pilates and PFMT groups measured 14.9 +/- 12.5 and 12.5 +/- 10.4 cmH(2)O, respectively (p = 0.41). Both the Pilates and PFMT groups got stronger (6.2 +/- 7.5 cmH(2)O, p = 0.0002 and 6.6 +/- 7.4 cmH(2)O, p = 0.0002, respectively), with no difference between groups p = 0.85. PFIQ and PFDI scores improved from baseline but not between groups. Further study is required to determine if Pilates can actually treat pelvic floor dysfunction.

  1. Assessing the accuracy of subject-specific, muscle-model parameters determined by optimizing to match isometric strength.

    PubMed

    DeSmitt, Holly J; Domire, Zachary J

    2016-12-01

    Biomechanical models are sensitive to the choice of model parameters. Therefore, determination of accurate subject specific model parameters is important. One approach to generate these parameters is to optimize the values such that the model output will match experimentally measured strength curves. This approach is attractive as it is inexpensive and should provide an excellent match to experimentally measured strength. However, given the problem of muscle redundancy, it is not clear that this approach generates accurate individual muscle forces. The purpose of this investigation is to evaluate this approach using simulated data to enable a direct comparison. It is hypothesized that the optimization approach will be able to recreate accurate muscle model parameters when information from measurable parameters is given. A model of isometric knee extension was developed to simulate a strength curve across a range of knee angles. In order to realistically recreate experimentally measured strength, random noise was added to the modeled strength. Parameters were solved for using a genetic search algorithm. When noise was added to the measurements the strength curve was reasonably recreated. However, the individual muscle model parameters and force curves were far less accurate. Based upon this examination, it is clear that very different sets of model parameters can recreate similar strength curves. Therefore, experimental variation in strength measurements has a significant influence on the results. Given the difficulty in accurately recreating individual muscle parameters, it may be more appropriate to perform simulations with lumped actuators representing similar muscles.

  2. HEAVY MANUAL WORK THROUGHOUT THE WORKING LIFETIME AND MUSCLE STRENGTH AMONG MEN AT RETIREMENT AGE

    PubMed Central

    Walker-Bone, K; D’Angelo, S; Syddall, HE; Palmer, KT; Cooper, C; Coggon, D; Sayer, AA

    2016-01-01

    Introduction Reductions in heavy manual work as a consequence of mechanisation might impact adversely on muscle strength at older ages. We investigated the association between grip strength at retirement age and lifetime occupational exposure to physically demanding activities. Grip strength is an important predictor of long-term health and physical function in older people. Methods Grip strength (maximum of three readings in each hand) was measured in men from the Hertfordshire Cohort Study at a single examination when their mean age was 65.8 (SD 2.9) years. Associations with lifetime occupational exposure (ascertained by questionnaire) to three activities (standing/walking ≥4 hours/day; lifting ≥25 kg; and energetic work sufficient to induce sweating) were assessed by multivariable linear regression with adjustment for various potential confounders. Results Complete data were available from 1,418 men who had worked for at least 20 years. After adjustment for age, height and weight, those with longer exposures to walking/standing and heavy lifting had lower grip strength, but the relationship disappeared after further adjustment for confounders. Working at physical intensity sufficient to induce sweating was not significantly associated with grip strength. Conclusions We found no evidence that physically demanding occupational activities increase hand grip strength at normal retirement age. Any advantages of regular physical occupational activity may have been obscured by unmeasured socio-economic confounders. PMID:26896253

  3. Effect of posture on oxygenation and respiratory muscle strength in convalescent infants

    PubMed Central

    Dimitriou, G; Greenough, A; Pink, L; McGhee, A; Hickey, A; Rafferty, G

    2002-01-01

    Objective: To determine if differences in respiratory muscle strength could explain any posture related effects on oxygenation in convalescent neonates. Methods: Infants were examined in three postures: supine, supine with head up tilt of 45°, and prone. A subsequent study was performed to determine the influence of head position in the supine posture. In each posture/head position, oxygen saturation (SaO2) was determined and respiratory muscle strength assessed by measurement of the maximum inspiratory pressure (PIMAX). Patients: Twenty infants, median gestational age 34.5 weeks (range 25–43), and 10 infants, median gestational age 33 weeks (range 30–36), were entered into the first and second study respectively. Results: Oxygenation was higher in the prone and supine with 45° head up tilt postures than in the supine posture (p<0.001), whereas PIMAX was higher in the supine and supine with head up tilt of 45° postures than in the prone posture (p<0.001). Head position did not influence the effect of posture on PIMAX or oxygenation. Conclusion: Superior oxygenation in the prone posture in convalescent infants was not explained by greater respiratory muscle strength, as this was superior in the supine posture. PMID:11978742

  4. Resistance training and aerobic training improve muscle strength and aerobic capacity in chronic inflammatory demyelinating polyneuropathy.

    PubMed

    Markvardsen, Lars H; Overgaard, Kristian; Heje, Karen; Sindrup, Søren H; Christiansen, Ingelise; Vissing, John; Andersen, Henning

    2018-01-01

    We investigated the effects of aerobic and resistance exercise in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Eighteen CIDP patients treated with subcutaneous immunoglobulin performed 12 weeks of aerobic exercise and 12 weeks of resistance exercise after a run-in period of 12 weeks without exercise. Three times weekly the participants performed aerobic exercise on an ergometer bike or resistance exercise with unilateral training of knee and elbow flexion/extension. Primary outcomes were maximal oxygen consumption velocity (VO 2 -max) and maximal combined isokinetic muscle strength (cIKS) of knee and elbow flexion/extension. VO 2 -max and muscle strength were unchanged during run-in (-4.9% ± 10.3%, P = 0.80 and -3.7% ± 10.1%, P = 0.17, respectively). Aerobic exercise increased VO 2 -max by 11.0% ± 14.7% (P = 0.02). Resistance exercise resulted in an increase of 13.8% ± 16.0% (P = 0.0004) in cIKS. Aerobic exercise training and resistance exercise training improve fitness and strength in CIDP patients. Muscle Nerve 57: 70-76, 2018. © 2017 Wiley Periodicals, Inc.

  5. Effects of egg white protein supplementation on muscle strength and serum free amino acid concentrations.

    PubMed

    Hida, Azumi; Hasegawa, Yuko; Mekata, Yuko; Usuda, Mika; Masuda, Yasunobu; Kawano, Hitoshi; Kawano, Yukari

    2012-10-19

    The aim of this study was to evaluate the effects of egg white protein compared to carbohydrate intake prior to exercise on fat free mass (FFM), one repetition maximum (1RM) muscle strength and blood biochemistry in female athletes. Thirty healthy female collegiate athletes were recruited for this study and matched by sport type, body fat percentage and 1RM leg curl muscle strength. Participants were randomly divided into two groups: protein group (15.0 g egg white protein; 75 kcal) and carbohydrate group (17.5 g maltodextrin, 78 kcal). Supplements were administered daily at the same time in a double-blind manner prior to training during an 8-week period. Measurements were performed before and after the 8-week regimen. The mean dietary energy intake did not change throughout the study period. FFM and 1RM assessments (i.e., leg curl, leg extension, squat, and bench press) increased in both groups. Furthermore, serum urea and serum citrulline levels after the 8-week regimen increased significantly only in the protein group. Our findings indicated that compared to the carbohydrate supplement, the protein supplement was associated with some changes in protein metabolites but not with changes in body composition or muscle strength.

  6. Effects of Egg White Protein Supplementation on Muscle Strength and Serum Free Amino Acid Concentrations

    PubMed Central

    Hida, Azumi; Hasegawa, Yuko; Mekata, Yuko; Usuda, Mika; Masuda, Yasunobu; Kawano, Hitoshi; Kawano, Yukari

    2012-01-01

    The aim of this study was to evaluate the effects of egg white protein compared to carbohydrate intake prior to exercise on fat free mass (FFM), one repetition maximum (1RM) muscle strength and blood biochemistry in female athletes. Thirty healthy female collegiate athletes were recruited for this study and matched by sport type, body fat percentage and 1RM leg curl muscle strength. Participants were randomly divided into two groups: protein group (15.0 g egg white protein; 75 kcal) and carbohydrate group (17.5 g maltodextrin, 78 kcal). Supplements were administered daily at the same time in a double-blind manner prior to training during an 8-week period. Measurements were performed before and after the 8-week regimen. The mean dietary energy intake did not change throughout the study period. FFM and 1RM assessments (i.e., leg curl, leg extension, squat, and bench press) increased in both groups. Furthermore, serum urea and serum citrulline levels after the 8-week regimen increased significantly only in the protein group. Our findings indicated that compared to the carbohydrate supplement, the protein supplement was associated with some changes in protein metabolites but not with changes in body composition or muscle strength. PMID:23201768

  7. Strength training prior to muscle injury potentiates low-level laser therapy (LLLT)-induced muscle regeneration.

    PubMed

    Morais, Samuel Rodrigues Lourenço; Goya, Alexandre Ginei; Urias, Úrsula; Jannig, Paulo Roberto; Bacurau, Aline Villa Nova; Mello, Wagner Garcez; Faleiros, Paula Lazilha; Oliveira, Sandra Helena Penha; Garcia, Valdir Gouveia; Ervolino, Edilson; Brum, Patricia Chakur; Dornelles, Rita Cássia Menegati

    2017-02-01

    We evaluated whether strength training (ST) performed prior to skeletal muscle cryolesion would act as a preconditioning, improving skeletal muscle regeneration and responsiveness to low-level laser therapy (LLLT). Wistar rats were randomly assigned into non-exercised (NE), NE plus muscle lesion (NE + LE), NE + LE plus LLLT (NE + LE + LLLT), strength training (ST), ST + LE, and ST + LE + LLLT. The animals performed 10 weeks of ST (climbing ladder; 3× week; 80% overload). Forty-eight hours after the last ST session, tibialis anterior (TA) cryolesion was induced and LLLT (InGaAlP, 660 nm, 0.035 W, 4.9 J/cm 2 /point, 3 points, spot light 0.028 cm 2 , 14 J/cm 2 ) initiated and conducted daily for 14 consecutive days. The difference between intergroups was assessed using Student's t test and intragroups by two-way analysis of variance. Cryolesion induced massive muscle degeneration associated with inflammatory infiltrate. Prior ST improved skeletal regeneration 14-days after cryolesion and potentiated the regenerative response to LLLT. Cryolesion induced increased TNF-α levels in both NE + LE and ST + LE groups. Both isolated ST and LLLT reduced TNF-α to control group levels; however, prior ST potentiated LLLT response. Both isolated ST and LLLT increased IL-10 levels with no additional effect. In contrast, increased TA IL-6 levels were restricted to ST and ST + LE + LLLT groups. TA myogenin mRNA levels were not changed by neither prior ST or ST + LLLT. Both prior ST and LLLT therapies increased MyoD mRNA levels and, interestingly, combined therapies potentiated this response. Myf5 mRNA levels were increased only in ST groups. Taken together, our data provides evidences for prior ST potentiating LLLT efficacy in promoting skeletal muscle regeneration.

  8. Cervical Muscle Strength and Muscle Coactivation During Isometric Contractions in Patients With Migraine: A Cross-Sectional Study.

    PubMed

    Florencio, Lidiane Lima; de Oliveira, Anamaria Siriani; Carvalho, Gabriela Ferreira; Tolentino, Gabriella de Almeida; Dach, Fabiola; Bigal, Marcelo Eduardo; Fernández-de-las-Peñas, César; Bevilaqua Grossi, Débora

    2015-01-01

    This cross-sectional study investigated potential differences in cervical musculature in groups of migraine headaches vs. non-headache controls. Differences in cervical muscle strength and antagonist coactivation during maximal isometric voluntary contraction (MIVC) were analyzed between individuals with migraine and non-headache subjects and relationships between force with migraine and neck pain clinical aspects. A customized hand-held dynamometer was used to assess cervical flexion, extension, and bilateral lateral flexion strength in subjects with episodic migraine (n=31), chronic migraine (n = 21) and healthy controls (n = 31). Surface electromyography (EMG) from sternocleidomastoid, anterior scalene, and splenius capitis muscles were recorded during MIVC to evaluate antagonist coactivation. Comparison of main outcomes among groups was conducted with one-way analysis of covariance with the presence of neck pain as covariable. Correlations between peak force and clinical variables were demonstrated by Spearman's coefficient. Chronic migraine subjects exhibited lower cervical extension force (mean diff. from controls: 4.4 N/kg; mean diff from episodic migraine: 3.7 N/kg; P = .006) and spent significantly more time to generate peak force during cervical flexion (mean diff. from controls: 0.5 seconds; P = .025) and left lateral-flexion (mean diff. from controls: 0.4 seconds; mean diff. from episodic migraine: 0.5 seconds; P = .007). Both migraine groups showed significantly higher antagonist muscle coactivity of the splenius capitis muscle (mean diff. from controls: 20%MIVC, P = .03) during cervical flexion relative to healthy controls. Cervical extension peak force was moderately associated with the migraine frequency (rs: -0.30, P = .034), neck pain frequency (rs: -0.26, P = .020), and neck pain intensity (rs: -0.27, P = .012). Patients with chronic migraine exhibit altered muscle performance, took longer to reach peak of

  9. Hip strength and star excursion balance test deficits of patients with chronic ankle instability.

    PubMed

    McCann, Ryan S; Crossett, Ian D; Terada, Masafumi; Kosik, Kyle B; Bolding, Brenn A; Gribble, Phillip A

    2017-11-01

    To examine isometric hip strength in those with and without CAI, and determine the degree of Star Excursion Balance Test (SEBT) variance explained by isometric hip strength. Single-blinded, cross-sectional, case-control study. Thirty individuals with CAI, 29 lateral ankle sprain (LAS) copers, and 26 healthy controls participated. We assessed dynamic postural control with the SEBT anterior (SEBT-ANT), posteromedial (SEBT-PM), and posterolateral (SEBT-PL) reaches, and isometric hip extension (EXT), abduction (ABD) and external rotation (ER) strength with hand-held dynamometry. The CAI and LAS coper groups' involved limbs and randomly selected limbs in controls were tested. Separate Kruskal-Wallis tests compared SEBT scores and isometric hip strength between groups. Backwards linear regression models determined the degree of SEBT variance explained by isometric hip strength. Statistical significance was set a priori at P<0.05. The CAI group had lower SEBT-ANT scores compared to LAS copers (P=0.03) and controls (P=0.03). The CAI group had lower ABD compared to LAS copers (P=0.03) and controls (P=0.02). The CAI group had lower ER compared to LAS copers (P=0.01) and controls (P=0.01). ER (R 2 =0.25, P=0.01) and ABD (R 2 =0.25, P=0.01) explained 25% of the CAI group's SEBT-PM and SEBT-PL variances, respectively. The CAI group had deficient dynamic postural control and isometric hip strength compared to LAS copers and controls. Additionally, the CAI group's isometric hip strength significantly influenced dynamic postural control performance. Future CAI rehabilitation strategies should consider hip muscular strengthening to facilitate improvements in dynamic postural control. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  10. PID Controller Design for FES Applied to Ankle Muscles in Neuroprosthesis for Standing Balance

    PubMed Central

    Rouhani, Hossein; Same, Michael; Masani, Kei; Li, Ya Qi; Popovic, Milos R.

    2017-01-01

    Closed-loop controlled functional electrical stimulation (FES) applied to the lower limb muscles can be used as a neuroprosthesis for standing balance in neurologically impaired individuals. The objective of this study was to propose a methodology for designing a proportional-integral-derivative (PID) controller for FES applied to the ankle muscles toward maintaining standing balance for several minutes and in the presence of perturbations. First, a model of the physiological control strategy for standing balance was developed. Second, the parameters of a PID controller that mimicked the physiological balance control strategy were determined to stabilize the human body when modeled as an inverted pendulum. Third, this PID controller was implemented using a custom-made Inverted Pendulum Standing Apparatus that eliminated the effect of visual and vestibular sensory information on voluntary balance control. Using this setup, the individual-specific FES controllers were tested in able-bodied individuals and compared with disrupted voluntary control conditions in four experimental paradigms: (i) quiet-standing; (ii) sudden change of targeted pendulum angle (step response); (iii) balance perturbations that simulate arm movements; and (iv) sudden change of targeted angle of a pendulum with individual-specific body-weight (step response). In paradigms (i) to (iii), a standard 39.5-kg pendulum was used, and 12 subjects were involved. In paradigm (iv) 9 subjects were involved. Across the different experimental paradigms and subjects, the FES-controlled and disrupted voluntarily-controlled pendulum angle showed root mean square errors of <1.2 and 2.3 deg, respectively. The root mean square error (all paradigms), rise time, settle time, and overshoot [paradigms (ii) and (iv)] in FES-controlled balance were significantly smaller or tended to be smaller than those observed with voluntarily-controlled balance, implying improved steady-state and transient responses of FES

  11. Musculoskeletal strength, balance performance, and self-efficacy in elderly ving tsun chinese martial art practitioners: implications for fall prevention.

    PubMed

    Fong, Shirley S M; Ng, Shamay S M; Liu, Karen P Y; Pang, Marco Y C; Lee, H W; Chung, Joanne W Y; Lam, Priscillia L; Guo, X

    2014-01-01

    Objectives. To (1) compare the bone strength, lower limb muscular strength, functional balance performance, and balance self-efficacy between Ving Tsun (VT) martial art practitioners and nonpractitioners and (2) identify the associations between lower limb muscular strength, functional balance performance, and balance self-efficacy among the VT-trained participants. Methods. Thirty-five VT practitioners (mean age ± SD = 62.7 ± 13.3 years) and 49 nonpractitioners (mean age ± SD = 65.9 ± 10.5 years) participated in the study. The bone strength of the distal radius, lower limb muscular strength, functional balance performance, and balance self-efficacy were assessed using an ultrasound bone sonometer, the five times sit-to-stand test (FTSTS), the Berg balance scale (BBS), and the Chinese version of the activities-specific balance confidence scale, respectively. A multivariate analysis of covariance was performed to compare all the outcome variables between the two groups. Results. Elderly VT practitioners had higher radial bone strength on the dominant side (P < 0.05), greater lower limb muscular strength (P = 0.001), better functional balance performance (P = 0.003), and greater balance confidence (P < 0.001) than the nonpractitioners. Additionally, only the FTSTS time revealed a significant association with the BBS score (r = -0.575,  P = 0.013). Conclusions. VT may be a suitable health-maintenance exercise for the elderly. Our findings may inspire the development of VT fall-prevention exercises for the community-dwelling healthy elderly.

  12. Musculoskeletal Strength, Balance Performance, and Self-Efficacy in Elderly Ving Tsun Chinese Martial Art Practitioners: Implications for Fall Prevention

    PubMed Central

    Fong, Shirley S. M.; Ng, Shamay S. M.; Liu, Karen P. Y.; Pang, Marco Y. C.; Lee, H. W.; Chung, Joanne W. Y.; Lam, Priscillia L.; Guo, X.

    2014-01-01

    Objectives. To (1) compare the bone strength, lower limb muscular strength, functional balance performance, and balance self-efficacy between Ving Tsun (VT) martial art practitioners and nonpractitioners and (2) identify the associations between lower limb muscular strength, functional balance performance, and balance self-efficacy among the VT-trained participants. Methods. Thirty-five VT practitioners (mean age ± SD = 62.7 ± 13.3 years) and 49 nonpractitioners (mean age ± SD = 65.9 ± 10.5 years) participated in the study. The bone strength of the distal radius, lower limb muscular strength, functional balance performance, and balance self-efficacy were assessed using an ultrasound bone sonometer, the five times sit-to-stand test (FTSTS), the Berg balance scale (BBS), and the Chinese version of the activities-specific balance confidence scale, respectively. A multivariate analysis of covariance was performed to compare all the outcome variables between the two groups. Results. Elderly VT practitioners had higher radial bone strength on the dominant side (P < 0.05), greater lower limb muscular strength (P = 0.001), better functional balance performance (P = 0.003), and greater balance confidence (P < 0.001) than the nonpractitioners. Additionally, only the FTSTS time revealed a significant association with the BBS score (r = −0.575,  P = 0.013). Conclusions. VT may be a suitable health-maintenance exercise for the elderly. Our findings may inspire the development of VT fall-prevention exercises for the community-dwelling healthy elderly. PMID:25530782

  13. Effect of neuromuscular electrical stimulation on facial muscle strength and oral function in stroke patients with facial palsy

    PubMed Central

    Choi, Jong-Bae

    2016-01-01

    [Purpose] The aim of this study was to investigate the effect of neuromuscular electrical stimulation on facial muscle strength and oral function in stroke patients with facial palsy. [Subjects and Methods] Nine subjects received the electrical stimulation and traditional dysphagia therapy. Electrical stimulation was applied to stimulate each subject’s facial muscles 30 minutes a day, 5 days a week, for 4 weeks. [Results] Subjects showed significant improvement in cheek and lip strength and oral function after the intervention. [Conclusion] This study demonstrates that electrical stimulation improves facial muscle strength and oral function in stroke patients with dysphagia. PMID:27799689

  14. Hip-Extensor Strength, Trunk Posture, and Use of the Knee-Extensor Muscles During Running.

    PubMed

    Teng, Hsiang-Ling; Powers, Christopher M

    2016-07-01

    Diminished hip-muscle performance has been proposed to contribute to various knee injuries. To determine the association between hip-extensor muscle strength and sagittal-plane trunk posture and the relationships among hip-extensor muscle strength and hip- and knee-extensor work during running. Descriptive laboratory study. Musculoskeletal biomechanical laboratory. A total of 40 asymptomatic recreational runners, 20 men (age = 27.1 ± 7.0 years, height = 1.74 ± 0.69 m, mass = 71.1 ± 8.2 kg) and 20 women (age = 26.2 ± 5.8 years, height = 1.65 ± 0.74 m, mass = 60.6 ± 6.6 kg), participated. Maximum isometric strength of the hip extensors was assessed using a dynamometer. Sagittal-plane trunk posture (calculated relative to the global vertical axis) and hip- and knee-extensor work (sum of energy absorption and generation) during the stance phase of running were quantified while participants ran over ground at a controlled speed of 3.4 m/s. We used Pearson product moment correlations to examine the relationships among hip-extensor strength, mean sagittal-plane trunk-flexion angle, hip-extensor work, and knee-extensor work. Hip-extensor strength was correlated positively with trunk-flexion angle (r = 0.55, P < .001) and hip-extensor work (r = 0.46, P = .003). It was correlated inversely with knee-extensor work (r = -0.39, P = .01). All the correlations remained after adjusting for sex. Our findings suggest that runners with hip-extensor weakness used a more upright trunk posture. This strategy led to an overreliance on the knee extensors and may contribute to overuse running injuries at the knee.

  15. Dysphagia risk, low muscle strength and poor cognition predict malnutrition risk in older adults athospital admission.

    PubMed

    Chatindiara, Idah; Allen, Jacqueline; Popman, Amy; Patel, Darshan; Richter, Marilize; Kruger, Marlena; Wham, Carol

    2018-03-21

    Malnutrition in patients admitted to hospital may have detrimental effects on recovery and healing. Malnutrition is preceded by a state of malnutrition risk, yet malnutrition risk is often not detected during admission. The aim of the current study was to investigate the magnitude and potential predictors of malnutrition risk in older adults, at hospital admission. A cross-sectional was study conducted in 234 older adults (age ≥ 65 or ≥ 55 for Māori or Pacific ethnicity) at admission to hospital in Auckland, New Zealand. Assessment of malnutrition risk status was performed using the Mini Nutritional Assessment Short-Form (MNA®-SF), dysphagia risk by the Eating Assessment Tool (EAT-10), muscle strength by hand grip strength and cognitive status by the Montreal Cognitive Assessment (MoCA) tool. Among 234 participants, mean age 83.6 ± 7.6 years, 46.6% were identified as at malnutrition risk and 26.9% malnourished. After adjusting for age, gender and ethnicity, the study identified [prevalence ratio (95% confidence interval)] high dysphagia risk [EAT-10 score: 0.98 (0.97-0.99)], low body mass index [kg/m 2 : 1.02 (1.02-1.03)], low muscle strength [hand grip strength, kg: 1.01 (1.00-1.02)] and decline in cognition [MoCA score: 1.01 (1.00-1.02)] as significant predictors of malnutrition risk in older adults at hospital admission. Among older adults recently admitted to the hospital, almost three-quarters were malnourished or at malnutrition risk. As the majority (88%) of participants were admitted from the community, this illustrates the need for routine nutrition screening both at hospital admission and in community-dwelling older adults. Factors such as dysphagia, unintentional weight loss, decline in muscle strength, and poor cognition may indicate increased risk of malnutrition.

  16. Ankle and toe muscle strength characteristics in runners with a history of medial tibial stress syndrome.

    PubMed

    Saeki, Junya; Nakamura, Masatoshi; Nakao, Sayaka; Fujita, Kosuke; Yanase, Ko; Morishita, Katsuyuki; Ichihashi, Noriaki

    2017-01-01

    A high proportion of flexor digitorum longus attachment is found at the posteromedial border of the tibia, which is the most common location of medial tibial stress syndrome (MTSS). Therefore, plantar flexion strength of the lesser toes could be related to MTSS; however, the relationship between MTSS and muscle strength of the hallux and lesser toes is not yet evaluated due to the lack of quantitative methods. This study investigated the muscle strength characteristics in runners with a history of MTSS by using a newly developed device to measure the muscle strength of the hallux, lesser toes, and ankle. This study comprised 27 collegiate male runner participants (20.0 ± 1.6 years, 172.1 ± 5.1 cm, 57.5 ± 4.0 kg). Maximal voluntary isometric contraction (MVIC) torque of the plantar flexion, dorsiflexion, inversion, and eversion of the ankle were measured by using an electric dynamometer. MVIC torque of the 1st metatarsophalangeal joint (MTPJ) and 2nd-5th MTPJ were measured by using a custom-made torque-measuring device. MVIC torques were compared between runners with and without a history of MTSS. MVIC torque of the 1st MTPJ plantar flexion was significantly higher in runners with a history of MTSS than in those without it. In contrast, there were no significant differences in the MVIC torque values of the 2nd-5th MTPJ plantar flexion and each MVIC torque of the ankle between runners with and without a history of MTSS. A history of MTSS increased the isometric FHL strength.

  17. Balance control and anti‐gravity muscle activity during the experience of fear at heights

    PubMed Central

    Wuehr, Max; Kugler, Guenter; Schniepp, Roman; Eckl, Maria; Pradhan, Cauchy; Jahn, Klaus; Huppert, Doree