Search

Purpose: Numerous daily tasks such as walking and rising from a chair involve bilateral lower limb movements. During such tasks, lower extremity function (LEF) may be compromised among older adults. LEF may be further impaired due to high degrees of between-limb asymmetry. The present study investigated the prevalence of between-limb asymmetry in muscle mass, strength, and power in a cohort of healthy older adults and examined the influence of between-limb asymmetry on LEF., Methods: Two hundred and eight healthy older adults (mean age 70.2 ± 3.9 years) were tested for LEF (400 m walking and 30-seconds chair stand). Furthermore, maximal isometric and dynamic knee extensor strength, leg extensor power, and lower limb lean tissue mass (LTM) were obtained unilaterally., Results: Mean between-limb asymmetry in maximal muscle strength and power ranged between 10% and 13%, whereas LTM asymmetry was 3 ± 2.3%. Asymmetry in dynamic knee extensor strength was larger for women compared with men (15.0 ± 11.8% vs 11.1 ± 9.5%; P = .005) Leg strength and power were positively correlated with LEF (r 2  = .43-.46, P < .001). The weakest leg was not a stronger predictor of LEF than the strongest leg. Between-limb asymmetry in LTM and isometric strength was negatively associated with LEF (LTM; r 2  = .12, P = .005, isometric peak torque; r 2  = 0.40, P = .03.) but dynamic strength and power were not., Conclusion: The present study supports the notion that in order to improve or maintain LEF, healthy older adults should participate in training interventions that increase muscle strength and power, whereas the effects of reducing between-limb asymmetry in these parameters might be of less importance., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background and Purpose: Patients with hip osteoarthritis have impairments in muscle function (muscle strength and power) and hip range of motion (ROM), and it is commonly believed that effective clinical management of osteoarthritis should address these impairments to reduce pain and disability. Therefore, the purpose of this study was to compare the short- and long-term effects of 4 months of physiotherapist-supervised strength training, physiotherapist-supervised Nordic Walking (NW), or unsupervised home-based exercise (HBE) on muscle function and hip ROM in patients diagnosed with hip osteoarthritis., Methods: Secondary outcome analyses from an observer-blinded three-armed parallel-design randomized controlled trial in 60+-year-old patients with clinical hip osteoarthritis (American College of Rheumatology criteria) who were not on a waiting list for hip replacement. One hundred and fifty-two patients were randomized to either 4 months of physiotherapist-supervised, moderate, progressive, strength training (n = 50), physiotherapist-supervised NW (n = 50), or unsupervised HBE (n = 52). Maximal isometric hip and thigh muscle strength and leg extensor power and active hip ROM were assessed at baseline 2, 4, and 12 months., Results: Intention-to-treat-analyses did not show any significant between-group differences for improvements in muscle strength and power or ROM at any time points. Short-term significant (p < .05) increases in muscle strength were present in the physiotherapist-supervised exercise groups and in the long-term for muscle power in the NW-group. All exercise modes resulted in significant increases of ROM but long-term improvements were only shown for NW and HBE., Discussion: Four months of physiotherapist-supervised, progressive, moderate, and strength training was less effective than hypothesized for improving muscle strength and power in patients with hip osteoarthritis who are not awaiting hip replacement. Our results may indicate that in these patients, improvements in disability are not necessarily dependent on improvements in strength and power or ROM., (Copyright © 2017 John Wiley & Sons, Ltd.)

Purpose: To investigate between-leg differences in hip and thigh muscle strength and leg extensor power in patients with unilateral hip osteoarthritis. Further, to compare between-leg differences in knee extensor strength and leg extensor power between patients and healthy peers., Methods: Seventy-two patients (60-87 years) with radiographic and symptomatic hip osteoarthritis not awaiting hip replacement and 35 healthy peers (63-82 years) were included. Hip and thigh muscle strength and leg extensor power were measured in patients and knee extensor strength and leg extensor power in healthy., Results: The symptomatic extremity in patients was significantly (p < 0.05, paired t-test) weaker compared with the non-symptomatic extremity for five hip muscles (8-17%), knee extensors (11%) and leg extensor power (19%). Healthy older adults had asymmetry in knee extensor strength (6%, p < 0.05) comparable to that found in patients, but had no asymmetry in leg extensor power., Conclusions: Patients had generalized weakening of the affected lower extremity and numerically the largest asymmetry was evident for leg extensor power. In contrast, healthy peers had no asymmetry in leg extensor power. These results indicate that exercise interventions focusing on improving leg extensor power of the symptomatic lower extremity and reducing asymmetry may be beneficial for patients with hip osteoarthritis. Implications for Rehabilitation Even in patients with mild symptoms not awaiting hip replacement a generalized muscle weakening of the symptomatic lower extremity seems to be present. Between-leg differences in leg extensor power (force × velocity) appears to be relatively large (19%) in patients with unilateral hip osteoarthritis in contrast to healthy peers who show no asymmetry. Compared to muscle strength the relationship between functional performance and leg extensor power seems to be stronger, and more strongly related to power of the symptomatic lower extremity. Our results indicate that exercise interventions focusing on improving leg extensor power of the symptomatic lower extremity and reducing asymmetry may be beneficial for patients with mild symptoms not awaiting hip replacement.

Age-related loss of muscle mass and function represents personal and socioeconomic challenges. The purpose of this study was to determine the adaptation of skeletal musculature in very old individuals (83+ years) performing 12weeks of heavy resistance training (3×/week) (HRT) compared to a non-training control group (CON). Both groups received similar protein supplementations. We studied 26 participants (86.9±3.2 (SD) (83-94, range) years old) per-protocol. Quadriceps cross-sectional area (CSA) differed between groups at post-test (P<0.05) and increased 1.5±0.7cm 2 (3.4%) (P<0.05) in HRT only. The increase in CSA is correlated inversely with the baseline level of CSA (R 2 =0.43, P<0.02). Thigh muscle isometric strength, isokinetic peak torque and power increased significantly only in HRT by 10-15%, whereas knee extension one-repetition maximum (1 RM) improved by 91%. Physical functional tests, muscle fiber type distribution and size did not differ significantly between groups. We conclude that in protein supplemented very old individuals, heavy resistance training can increase muscle mass and strength, and that the relative improvement in mass is more pronounced when initial muscle mass is low., (Copyright © 2017. Published by Elsevier Inc.)

Objective: To investigate the reliability and agreement of measures of lower extremity muscle strength, power and functional performance in patients with hip osteoarthritis at different time intervals, and to compare these with the same measures in healthy peers., Design: Intra-rater test-retest separated by 1, 2, or 2.5 weeks in patients, and 1 week in healthy peers., Subjects: Patients with hip osteoarthritis (age range 61-83 years) with 1 (n = 37), 2 (n = 35), or 2.5 weeks (n = 15) between tests, and 35 healthy peers (age range 63-82 years)., Methods: Maximal isometric hip and thigh strength, leg extensor power, and functional performance (8-foot Up & Go, stair climbing, chair stand and 6-min walk) were measured in patients, and quadriceps strength, leg extensor power and functional performance were measured in healthy peers. Systematic error, reliability and agreement were calculated., Results: Most hip strength measurements for the most symptomatic extremity, and nearly all strength measurements for the least symptomatic lower extremity, declined after 1 week (p < 0.05), but not after a 2.5-week interval. In healthy peers, quadriceps strength was unchanged. Regardless of the time interval, leg extensor power was unchanged, while functional performances improved at retest for all participants., Conclusion: In patients with hip osteoarthritis leg extensor power is unaffected by the time interval between tests, in contrast to muscle strength and functional performance.

Objective: Persistent weakness is a common problem after anterior cruciate ligament- (ACL-) reconstruction. This study investigated the effects of high-intensity (HRT) versus low-intensity (LRT) resistance training on leg extensor power and recovery of knee function after ACL-reconstruction., Methods: 31 males and 19 females were randomized to HRT (n = 24) or LRT (n = 26) from week 8-20 after ACL-reconstruction. Leg extensor power, joint laxity, and self-reported knee function were measured before and 7, 14, and 20 weeks after surgery. Hop tests were assessed before and after 20 weeks., Results: Power in the injured leg was 90% (95% CI 86-94%) of the noninjured leg, decreasing to 64% (95% CI 60-69%) 7 weeks after surgery. During the resistance training phase there was a significant group by time interaction for power (P = 0.020). Power was regained more with HRT compared to LRT at week 14 (84% versus 73% of noninjured leg, resp.; P = 0.027) and at week 20 (98% versus 83% of noninjured leg, resp.; P = 0.006) without adverse effects on joint laxity. No other between-group differences were found., Conclusion: High-intensity resistance training during rehabilitation after ACL-reconstruction can improve muscle power without adverse effects on joint laxity.

Objective: To describe associations of muscle strength, physical activity and self-rated health., Method: Isometric muscle strength by maximal handgrip strength (HGS) or muscle strength by 30s repeated chair stand test (30s-CS) was combined with leisure time physical activity. Using logistic regression odds ratio was calculated for good self-rated health according to the combined associations among 16,539 participants (59.7% women), mean age 51.9 (SD: 13.8) years, from a cross-sectional study in Denmark 2007-2008., Results: Good self-rated health was positively associated with higher levels of physical activity and greater muscle strength. Regarding HGS the highest OR for good self-rated health was in the moderate/vigorous physically active participants with high HGS (OR=6.84, 95% CI: 4.85-9.65 and OR=7.34, 95% CI: 5.42-9.96 for men and women, respectively). Similarly the highest OR for good self-rated health was in the moderate/vigorous physically active participants with high scores in the 30s-CS test (6.06, 95% CI: 4.32-8.50 and 13.38, 95% CI: 9.59-18.67 for men and women, respectively). The reference groups were sedentary participants with low strength (HGS or 30s-CS)., Conclusion: The combined score for physical activity level with either HGS or 30s-CS was strongly positively associated with self-related health., (© 2013.)

Objective: Acute hospitalization of older patients may be associated with loss of muscle strength and functional performance. The aim of this study was to investigate the effect of acute hospitalization as a result of medical disease on muscle strength and functional performance in older medical patients., Design: Isometric knee-extension strength; handgrip strength; and functional performance, that is, the Timed Up and Go test, were assessed at admission, at discharge, and 30 days after discharge. Twenty-four-hour mobility was measured during hospitalization., Results: The mean (SD) age was 82.7 (8.2) years, and the median length of stay was 7.5 days (interquartile range, 4.25-11). Knee-extension strength did not change over time (1.0 [N·m]/kg, 1.1 [N·m]/kg, and 1.1 [N·m]/kg, P = 0.138), as did handgrip strength (24.2 kg, 23.3 kg, and 23.5 kg, P = 0.265). The Timed Up and Go test improved during hospitalization, from 17.3 secs at admission to 13.3 secs at discharge (P = 0.003), but with no improvement at the 30-day follow-up (12.4 secs, P = 0.064). The median times spent in lying, sitting, and standing/walking were 17.4 hrs per day, 4.8 hrs per day, and 0.8 hrs per day, respectively., Conclusions: Muscle strength did not change during hospitalization and 30 days after discharge in the acutely admitted older medical patients. Despite a low level of mobility during hospitalization, functional performance improved significantly during hospitalization, without further improvement.

Objectives: To investigate the effect of 12 weeks of strength training in combination with a nonsteroidal anti-inflammatory drug (NSAID), glucosamine, or placebo on muscle cross-sectional area (CSA), strength (primary outcome parameters), and function, power, pain, and satellite cell number (secondary outcome parameters) in patients with knee osteoarthritis (OA)., Design: Double-blinded, randomized controlled trial., Setting: Hospital., Participants: Patients (N=36; 20 women, 16 men; age range, 50-70y) with bilateral tibiofemoral knee OA. A total of 181 patients were approached, and 145 were excluded., Interventions: Patients were randomly assigned to treatment with the NSAID ibuprofen (n=12), glucosamine (n=12), or placebo (n=12) during 12 weeks of quadriceps muscle strength training., Main Outcome Measures: Muscle CSA and strength., Results: No differences between groups were observed in gains in muscle CSA. Training combined with ibuprofen increased maximal isometric strength by an additional .22Nm/kg (95% confidence interval [CI], .01-.42; P=.04), maximal eccentric muscle strength by .38Nm/kg (95% CI, .05-.70; P=.02), and eccentric muscle work by .27J/kg (95% CI, .01-.53; P=.04) in comparison with placebo. Training combined with glucosamine increased maximal concentric muscle work by an additional .24J/kg versus placebo (95% CI, .06-.42; P=.01)., Conclusions: In patients with knee OA, NSAID or glucosamine administration during a 12-week strength-training program did not improve muscle mass gain, but improved maximal muscle strength gain in comparison with treatment with placebo. However, we do not find that the benefits are large enough to justify taking NSAIDs or glucosamine., (Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Restricted physical activity as a consequence of chronic disease or injury is a predictor of functional decline. The aim of this study was to test the hypothesis that a 6- month multidimensional training program would have sustained beneficial effects upon the physiological, functional and psychological condition of old women with a recent history of falls., Methods: Participants were 65 home-dwelling women (70-90 years) identified from hospital records as having had an accidental fall. After assessment of muscle strength, balance performance, walking speed, balance confidence, and physical activity level, the participants were randomly assigned to a control group (n=33) or a training group (n=32), who performed a multidimensional training program including moderate resistance exercise and balance exercise twice weekly for 6 months. Measurements were repeated after 6 and 12 months., Results: Six months of multidimensional training resulted in significant improvements and between-group differences in isometric knee extension strength (p<0.05), trunk extension/ flexion strength (p<0.001), habitual/maximal walking speed (p<0.001) and balance performance (p<0.001). At follow-up, 6 months after intervention, these improvements were preserved in the training group and there was also a significant between- group difference with regard to balance confidence. No between-group differences were found concerning number of falls or physical activity level during the one-year study period., Conclusions: A multi-dimensional training program produced significant improvements in physiological and functional risk factors for falls and disability in women aged 70-90 years with a recent history of falls.

Immobilization due to hospitalization and major surgery leads to an increased risk of morbidity, disability and a decline in muscle function especially in frail elderly individuals. In fact, many elderly patients fail to regain their level of function and self-care before admission to hospital. Given that reduced lower limb muscle strength and loss of skeletal muscle mass (i.e. sarcopenia) have been associated with functional impairments and disability with aging, attempts to counteract this process seem highly relevant. In recent years, strength training has emerged as an effective method to induce muscle hypertrophy and increase muscle strength and functional performance in frail elderly individuals. Furthermore, there is increasing evidence that strength training is an effective method to restore muscle function in post-operative patients and in patients with chronic diseases. Despite this, strength training is rarely used in the rehabilitation of hospitalized elderly patients. The current knowledge on this topic will be the focus of this review. [ABSTRACT FROM AUTHOR]

The aim of the present study was to describe the isokinetic strength profile and its relation to hiking performance in male (SM, n=15) and female (SF, n=6) elite sailors compared to a group of male control subjects (CM, n=8) similar in age, anthropometry and level of fitness. Eccentric knee extension strength was higher in SM compared to CM(P<0.01). Furthermore, SM were stronger during trunk extension (P<0.05), but not during trunk flexion compared to CM. Overall muscle strength was lower in SF compared to SM (P<0.01) and CM (P<0.05), except for eccentric knee extension strength, where SF and CM did not differ (P>0.05). Hiking performance correlated to maximal eccentric and isometric knee extensor strength in SF (r[subs=0.83-088, P<0.05) and in CM (r[subs]=0.73-0.77, P<0.05) and to maximal eccentric knee extensor strength at high velocity in SM (r[subs]=0.46-0.54, P<0.05). For a subgroup of hikers in SM (n=8), hiking performance correlated to maximal isometric-eccentric knee extensor strength (r[subs]=0.67-0.74, P<0.05), whereas no correlations emerged for the non-hikers (n=7). Few correlations were observed between hiking performance and maximal concentric trunk flexor strength (r[subs]=0.69-0.92, P<0.05). Unexpectedly, in SM correlations also were observed between hiking performance and maximal strength of the trunk extensors (r[subs]=0.460.53, hiker subgroup: r[subs]=0.64-0.67, P<0.05). In conclusion, notably high levels of maximal eccentric knee extensor strength were observed for the male and female elite sailors examined in the present study. Furthermore, the present results suggest that hiking performance depends in part on maximal isometric-eccentric knee extensor strength. The maximal strength of the trunk extensors, which potentially stabilizes the lower back and spine, also seems to have some importance for the hiking performance of top-level sailors. [ABSTRACT FROM AUTHOR]