•High physical activity (PA) is associated with better muscle strength and power.•Low sedentary behavior (SB) is associated with better muscle strength and power.•PA/SB are stronger associated with ...lower body muscle strength and power than upper.•Strongest associations were found for PA/SB with chair stand test performance.•Confounding does not affect the association of PA/SB with muscle strength/power.
Engaging in physical activity (PA) and avoiding sedentary behavior (SB) are important for healthy ageing with benefits including the mitigation of disability and mortality. Whether benefits extend to key determinants of disability and mortality, namely muscle strength and muscle power, is unclear.
This systematic review aimed to describe the association of objective measures of PA and SB with measures of skeletal muscle strength and muscle power in community-dwelling older adults.
Six databases were searched from their inception to June 21st, 2020 for articles reporting associations between objectively measured PA and SB and upper body or lower body muscle strength or muscle power in community dwelling adults aged 60 years and older. An overview of associations was visualized by effect direction heat maps, standardized effect sizes were estimated with albatross plots and summarized in box plots. Articles reporting adjusted standardized regression coefficients (β) were included in meta-analyses.
A total of 112 articles were included representing 43,796 individuals (range: 21 to 3726 per article) with a mean or median age from 61.0 to 88.0 years (mean 56.4 % female). Higher PA measures and lower SB were associated with better upper body muscle strength (hand grip strength), upper body muscle power (arm curl), lower body muscle strength, and lower body muscle power (chair stand test). Median standardized effect sizes were consistently larger for measures of PA and SB with lower compared to upper body muscle strength and muscle power. The meta-analyses of adjusted β coefficients confirmed the associations between total PA (TPA), moderate-to-vigorous PA (MVPA) and light PA (LPA) with hand grip strength (β = 0.041, β = 0.057, and β = 0.070, respectively, all p ≤ 0.001), and TPA and MVPA with chair stand test (β = 0.199 and β = 0.211, respectively, all p ≤ 0.001).
Higher PA and lower SB are associated with greater skeletal muscle strength and muscle power, particularly with the chair stand test.
ABSTRACTIkezoe, T, Kobayashi, T, Nakamura, M, and Ichihashi, N. Effects of low-load, higher-repetition vs. high-load, lower-repetition resistance training not performed to failure on muscle strength, ...mass, and echo intensity in healthy young menA time-course study. J Strength Cond Res 34(12)3439–3445, 2020—The aim of this study was to compare the effects of low-load, higher-repetition training (LLHR) with those of high-load, lower-repetition training (HLLR) on muscle strength, mass, and echo intensity in healthy young men. Fifteen healthy men (age, 23.1 ± 2.6 years) were randomly assigned to 1 of the 2 groupsLLHR or HLLR group. Resistance training on knee extensor muscles was performed 3 days per week for 8 weeks. One repetition maximum (1RM) strength, maximum isometric strength, muscle thickness, and muscle echo intensity on ultrasonography of the rectus femoris muscle were assessed every 2 weeks. Analysis of variance showed no significant group × time interaction, and only a significant main effect of time was observed for all variables. The 8-week resistance training increased 1RM, maximum isometric muscle strength, and muscle thickness by 36.2–40.9%, 24.0–25.5%, and 11.3–20.4%, respectively, whereas it decreased echo intensity by 8.05–16.3%. Significant improvements in muscle strength, thickness, and echo intensity were observed at weeks 2, 4, and 8, respectively. The lack of difference in time-course changes between LLHR and HLLR programs suggests that low-load training can exert similar effects on muscle mass and characteristics as high-load training by increasing the number of repetitions, even when not performed to failure.
We defined respiratory sarcopenia as a coexistence of respiratory muscle weakness and decreased respiratory muscle mass. Although respiratory muscle function is indispensable for life support, its ...evaluation has not been included in the regular assessment of respiratory function or adequately evaluated in clinical practice. Considering this situation, we prepared a position paper outlining basic knowledge, diagnostic and assessment methods, mechanisms, involvement in respiratory diseases, intervention and treatment methods, and future perspectives on respiratory sarcopenia, and summarized the current consensus on respiratory sarcopenia. Respiratory sarcopenia is diagnosed when respiratory muscle weakness and decreased respiratory muscle mass are observed. If respiratory muscle mass is difficult to measure, we can use appendicular skeletal muscle mass as a surrogate. Probable respiratory sarcopenia is defined when respiratory muscle weakness and decreased appendicular skeletal muscle mass are observed. If only respiratory muscle strength is decreased without a decrease in respiratory function, the patient is diagnosed with possible respiratory sarcopenia. Respiratory muscle strength is assessed using maximum inspiratory pressure and maximum expiratory pressure. Ultrasonography and computed tomography are commonly used to assess respiratory muscle mass; however, there are insufficient data to propose the cutoff values for defining decreased respiratory muscle mass. It was jointly prepared by the representative authors and authorized by the Japanese Society for Respiratory Care and Rehabilitation, Japanese Association on Sarcopenia and Frailty, Japanese Society of Respiratory Physical Therapy and Japanese Association of Rehabilitation Nutrition. Geriatr Gerontol Int 2023; 23: 5–15.
The study investigated the association between knee joint muscle strength and the prevalence of depression in a cohort of young adults.
The observational, population-based study was performed with ...909 participants (29.02 ± 2.03 years; 48.73% male) from the Central European Longitudinal Studies of Parents and Children: Young Adults (CELSPAC: YA), who were retained to analysis. Quadriceps and hamstring knee muscle strength were assessed by isokinetic dynamometry, and depression by Beck's Depression Inventory (BDI-II). Statistical comparisons (Mann-Whitney and Chi-squared test) and effect size analyses (Eta-Squared, and Odds Ratio) were conducted.
The main findings revealed an inverse association between knee joint muscle strength and depression, with individuals who had low muscle strength having 3.15 (95% CI = 2.74-3.62) times higher odds of experiencing depression. Specifically, participants with low extensor strength had 4.63 (95% CI = 2.20-9.74) times higher odds, and those with low flexor strength had 2.68 (95% CI = 1.47-4.89) times higher odds of experiencing depression compared to those individuals with high muscle strength. Furthermore, gender-specific analyses revealed that males with low muscle strength had 2.51 (95% CI = 1.53-4.14) times higher odds, while females had 3.46 (95% CI = 2.93-4.08) times higher odds of experiencing depression compared to individuals with high muscle strength.
Strong knee muscles seems to be a key factor in preventing depression, specially in female young adults. The results support the importance of promoting an increase in muscle strength through physical activity as a preventive strategy against depression in this population.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Physical activity recommendations for public health include typically muscle-strengthening activities for a minimum of 2 days a week. The range of inter-individual variation in responses to ...resistance training (RT) aiming to improve health and well-being requires to be investigated. The purpose of this study was to quantify high and low responders for RT-induced changes in muscle size and strength and to examine possible effects of age and sex on these responses. Previously collected data of untrained healthy men and women (age 19 to 78 years,
n
= 287 with 72 controls) were pooled for the present study. Muscle size and strength changed during RT are 4.8 ± 6.1 % (range from −11 to 30 %) and 21.1 ± 11.5 % (range from −8 to 60 %) compared to pre-RT, respectively. Age and sex did not affect to the RT responses. Fourteen percent and 12 % of the subjects were defined as high responders (>1 standard deviation (SD) from the group mean) for the RT-induced changes in muscle size and strength, respectively. When taking into account the results of non-training controls (upper 95 % CI), 29 and 7 % of the subjects were defined as low responders for the RT-induced changes in muscle size and strength, respectively. The muscle size and strength responses varied extensively between the subjects regardless of subject’s age and sex. Whether these changes are associated with, e.g., functional capacity and metabolic health improvements due to RT requires further studies.
To investigate whether the rate of change of muscle strength in people with joint hypermobility syndrome (JHS) who have anterior knee pain (AKP) differs when compared to 2 control groups who have AKP ...and to evaluate the relationship between strength and pain as well as the effect of strength upon activity and knee function.
A cohort study, with 3 groups: JHS with AKP, generalized joint hypermobility with AKP (GJH), and normal flexibility with AKP (control group CG). Follow-up appointments were performed every 2 weeks for 16 weeks.
The physiotherapy outpatient department within a London (United Kingdom) hospital.
A total of 102 people, aged between 18 and 55 years, were recruited between July 2014 and March 2016; 47 JHS, 29 GJH, and 26 CG (N=102). After 16 weeks, 31, 20, and 21 participants completed the study, respectively. Participants were recruited from support groups, a London hospital group and university, local sports centers, and clubs.
Individualized leg exercises for 16 weeks.
Muscle torque generated from the lower limb, every 2 weeks for 16 weeks.
There was no difference in the rate of change of concentric muscle strength between the JHS group and the CG or GJH group (P>.88 and P>.97). There was no difference in the rate of change of eccentric muscle strength between the JHS group and the CG or GJH group (P>.60 and P>.94). However, people with JHS were significantly weaker than the other 2 groups, taking 3 to 4 months to reach the baseline strength of the GJH group.
People with JHS can strengthen at the same rate as other people in pain.
Introduction: Both grip and knee extension strength are often used to characterize overall limb muscle strength. We sought to determine if the measures actually reflect a common construct. Methods: ...The isometric grip and knee extension strength of 164 healthy men and women (range, 18–85 years) were measured bilaterally using standard procedures. Pearson correlations (r), Cronbach alpha, principal components analysis, and multiple regression/correlation were used to investigate the dimensionality of the measures. Results: Left and right grip forces and knee extension torques were highly correlated, internally consistent, and loaded on a single component. Gender and age explained the variance in both measures, but height added to the explanation of grip strength, whereas weight added to the explanation of knee extension strength. Conclusions: Among healthy adults, grip and knee extension strength reflect a common underlying construct. The measures, however, are affected differently by height and weight. Muscle Nerve 46: 555–558, 2012
Objective
Numerous factors affect abductor strength after Total hip arthroplasty (THA), including surgical technique, prosthesis type, postoperative rehabilitation program, and preoperative patient ...condition. We prospectively investigated the effects of the modified Hardinge approach on hip muscle strength, which was evaluated using the isokinetic test, functional results, and gait function of patients who underwent primary THA.
Methods
The hip muscles strength were measured using an isokinetic dynamometer. The primary outcomes of the present study were measurement of isokinetic strength of hip abductor muscle strengths using an isokinetic evaluator and gait analyses preoperatively and at 6 months postoperatively in 27 patients.
Results
Isokinetic muscle strength test, abductor and other hip circumference groups achieved the preoperative muscle strength at 3 months postoperatively, and the postoperative sixth month values showed a statistically significant improvement compared with the preoperative and third month values. In gait analyze, our temporospatial data showed a slight regression at postoperative 3 months but reached the same values at 6 months postoperatively. Kinematic data showed a significant regression, but the data were not compared with those in the preoperative period.
Conclusions
Adequate muscle strength and physiological gait pattern, similar to the preoperative status, can be achieved at 6 months postoperatively.
Level of evidence
Level III.
Stretching is commonly practiced before sports participation; however, effects on subsequent performance and injury prevention are not well understood. There is an abundance of literature ...demonstrating that a single bout of stretching acutely impairs muscle strength, with a lesser effect on power. The extent to which these effects are apparent when stretching is combined with other aspects of a pre‐participation warm‐up, such as practice drills and low intensity dynamic exercises, is not known. With respect to the effect of pre‐participation stretching on injury prevention a limited number of studies of varying quality have shown mixed results. A general consensus is that stretching in addition to warm‐up does not affect the incidence of overuse injuries. There is evidence that pre‐participation stretching reduces the incidence of muscle strains but there is clearly a need for further work. Future prospective randomized studies should use stretching interventions that are effective at decreasing passive resistance to stretch and assess effects on subsequent injury incidence in sports with a high prevalence of muscle strains.
PURPOSEThis study aimed to prospectively investigate the association between isolated and functional lower extremity muscle strength and the risk for noncontact anterior cruciate ligament (ACL) ...injury in Norwegian female elite handball and football players.
METHODSFrom 2007 through 2015, premier league players participated in strength testing and were prospectively followed for ACL injury risk. At baseline, we recorded player demographics, playing and ACL injury history, and measured peak concentric isokinetic quadriceps and hamstring torques (60°·s), hamstring-to-quadriceps ratio, isometric hip abduction strength, and one-repetition maximum in a seated leg press. We followed a predefined statistical protocol where we generated five separate logistic regression models, one for each of the proposed strength risk factors and adjusted for confounding factors. New ACL injury was the outcome, using the leg as the unit of analysis.
RESULTSA total of 57 (6.6%) of 867 players (age = 21 ± 4 yr, height = 170 ± 6 cm, body mass = 66 ± 8 kg) suffered from a noncontact ACL injury after baseline testing (1.8 ± 1.8 yr). The OR of sustaining a new injury among those with an ACL injury history was 3.1 (95% confidence interval = 1.6–6.1). None of the five strength variables selected were statistically associated with an increased risk of ACL rupture when adjusted for sport, dominant leg, ACL injury history, and height.
CONCLUSIONPeak lower extremity strength was not associated with an increased ACL injury risk among female elite handball and football players. Hence, peak strength, as measured in the present study, cannot be used to screen elite female athletes to predict injury risk.
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