Comparison of two popular transducers to measure sit-to-stand power in older adults.

The Tendo Unit (TU) and GymAware (GA) are the two most frequently used linear transducers for assessing muscle power in older adults via the sit-to-stand (STS) test. Unlike TU, GA incorporates a sensor mechanism to correct for non-vertical movements, which may lead to systematic differences between devices. The aim of this study therefore was to compare GA to TU for measuring STS power in community-dwelling older adults. Community-dwelling adults (n = 51, aged ≥65 years, 61% female) completed a single chair stand, with peak power measured simultaneously using GA and TU. Participants also completed the pneumatic leg press, 8-Foot Up and Go (TUG) test, Short Physical Performance Battery (SPPB), and self-reported measures of physical function. Intraclass correlations (ICC) were used to assess agreement, and Pearson's correlations were used to assess correlations. The study protocol was prospectively registered on the Open Science Framework. In alignment with our pre-registered hypothesis, peak power demonstrated an ICC of 0.93 (95% CI: 0.88, 0.96). For secondary aims, both transducers showed a correlation greater than 0.8 compared to pneumatic leg press power. For physical performance outcomes, both TU and GA showed similar correlations, as hypothesized: SPPB (r = 0.29 for TU vs. 0.33 for GA), Chair Stands (r = -0.41 vs. -0.38), TUG Fast (r = -0.53 vs. -0.52), mobility questionnaire (r = 0.52 vs. 0.52) and physical function questionnaire (r = 0.44 vs. 0.43). GA and TU peak power showed a high degree of agreement and similar correlations with physical and self-reported performance measures, suggesting that both methods can be used for assessing STS power in older adults.

Criterion Validity and Reliability of 2 Brief Physical Activity Questionnaires in Ethnically Diverse Adults.

PURPOSE: The study compares moderate- to vigorous-intensity physical activity (MVPA) as evaluated by the Exercise Vital Signs (EVS) and Physical Activity Vital Signs (PAVS) questionnaires to accelerometry, and evaluates the reliability of the questionnaires in ethnically diverse adults. METHODS: Ninety-nine participants (mean age 38.1 y; 49.5% women; Hispanics 43.8%; European American 18.8%; African American 14.6%) were included in the analyses. Participants wore an accelerometer at the hip for at least 7 days and completed the EVS and PAVS questionnaires at the beginning (T1) and at the end (T2) of the 7 days. Associations between the questionnaires and accelerometry were examined using Spearman rho. The reliability of the questionnaires was evaluated using intraclass correlation coefficient. Sensitivity and specificity were also calculated. RESULTS: Weak positive correlations were observed between the accelerometer MVPA and the EVS MVPA at T2 (ρ = .263, P = .013), and the PAVS MVPA at T2 (ρ = .327, P = .003). The sensitivity of the EVS and PAVS was 73.2% and 82.6%, respectively. The specificity for each questionnaire was 35.3%. The reliability for the EVS questionnaire (intraclass correlation coefficient = .855; 95% CI, .791-.901; P < .001) was good, while the reliability of the PAVS questionnaire (intraclass correlation coefficient = .652; 95% CI, .511-.758; P < .001) was moderate. CONCLUSION: Caution should be used when utilizing the EVS and PAVS questionnaires in ethnically diverse adults.

Comparison of traditional vs. lighter load strength training on fat-free mass, strength, power and affective responses in middle and older-aged adults: A pilot randomized trial.

OBJECTIVES: Strength training is widely recommended to improve strength, muscle mass and power. However, the feasibility and potential efficacy of strength training using lighter loads near failure on these outcomes in middle and older-aged adults remains unclear. METHODS: 23 community-living adults were randomized into two groups: Traditional strength training (ST) (8-12 repetitions) or a lighter load, higher repetitions (LLHR) (20-24 repetitions) group. Participants performed a full-body workout (twice a week) with 8 exercises at a perceived exertion of 7-8 (0-10 scale) for 10 weeks. Post-testing was performed by an assessor blinded to group assignments. An analysis of covariance (ANCOVA) was used to examine between group differences using baseline values as a covariate. RESULTS: The study involved individuals with a mean age of 59 years, of which 61 % were women. The LLHR group demonstrated a high attendance rate of 92 % (9.5 %) and reported leg press exercise RPE of 7.1 (0.53), along with a session feeling scale of 2.0 (1.7). There was a trivial difference in fat free mass (FFM) favoring LLHR vs ST [0.27 kg 95 % CI (-0.87, 1.42)]. The ST group exhibited superior increases in leg press 1 repetition maximum (1RM) strength [-14 kg (-23, -5)], while the LLHR group showed greater strength endurance increases (65 % 1RM) [8 repetitions (2, 14)]. Leg press power [41 W (-42, 124)] and exercise efficacy [-3.8 (-21.2, 13.5)] demonstrated trivial between-group differences. CONCLUSION: A pragmatic, full-body strength training program with lighter loads taken close to failure appears to be a viable option for promoting muscular adaptations in middle- and older-aged adults. These results are exploratory and require a larger trial for confirmation.

Comparing D3-Creatine Dilution and Dual-Energy X-ray Absorptiometry Muscle Mass Responses to Strength Training in Low-Functioning Older Adults.

BACKGROUND: In contrast to dual-energy x-ray absorptiometry (DXA), the D3-creatine (D3Cr) dilution method provides a direct measure of skeletal muscle mass and in a cohort of older men has been strongly associated with health-related outcomes. However, sensitivity to detect changes in D3Cr-derived muscle mass due to an intervention is limited. METHODS: Twenty-one older adults (≥70 years) with low-to-moderate physical function were randomized to a 15-week high-intensity strength training (ST) or a health education (HE) group. Full-body progressive intensity ST was performed 3 days per week. RESULTS: The mean age was 82.1 years, with 64% females. After 15 weeks, both D3Cr muscle mass (MM; 2.29 kg; 95% CI: 0.22, 4.36) and DXA appendicular lean mass (ALM; 1.04 kg; 95% CI: 0.31, 1.77) were greater in ST group compared to HE. Baseline correlations between D3Cr MM and DXA ALM (r = 0.79; 95% CI: 0.53, 0.92) or total lean body mass (LBM; r = 0.79; 95% CI: 0.52, 0.91) were high. However, longitudinal changes in D3Cr MM were weakly correlated with changes in DXA ALM (r = 0.19; 95% CI: -0.35, 0.64) and LBM (r = 0.40; 95% CI: -0.13, 0.76). More participants showed positive response rates, defined as a >5% increase from baseline, with D3Cr MM (80%) than DXA measures (14%-43%). CONCLUSIONS: A progressive ST intervention in low-functioning older adults increased D3Cr MM and DXA ALM. These data suggest that the D3Cr dilution is potentially sensitive to detect changes in muscle mass in response to resistance exercise training. These results are preliminary and could be used for planning larger trials to replicate these results.

Comparison of Power Training vs Traditional Strength Training on Physical Function in Older Adults: A Systematic Review and Meta-analysis.

Importance: Strength training exercise is recommended for improving physical function in older adults. However, whether strength training (lifting and lowering weights under control) and power training (PT) (lifting weights fast and lowering under control) are associated with improved physical function in older adults is not clear. Objective: To evaluate whether PT vs traditional strength training is associated with physical function improvement in older adults. Data Sources: Systematic searches of MEDLINE, Embase, Cochrane Central, CINAHL, PsycInfo, PEDro, and SPORTDiscus were conducted from database inception to October 20, 2021. Study Selection: Randomized clinical trials (RCTs) that compared strength training with instructions to move the weight as fast as possible in the lifting phase with traditional strength training in healthy, community-living older adults (age ≥60 years). Data Extraction and Synthesis: Two authors independently selected trials, extracted data, assessed the risk of bias using the Cochrane risk-of-bias tool 2, and assessed the certainty of the evidence using the Grading of Recommendations, Assessment, Development and Evaluation approach. Summary effect size measures were calculated using a multilevel random-effects model with cluster robust variance estimation and are reported as standardized mean differences (SMDs). Reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline. Main Outcomes and Measures: Primary outcomes included physical function and self-reported physical function. Secondary outcomes included power, strength, muscle mass, walk speed, balance, and adverse effects. Results: A total of 20 RCTs enrolling 566 community-living older adults (mean [SD] age, 70.1 [4.8] years; 368 [65%] women) were included. For the primary outcomes, PT was associated with an improvement in physical function with low-certainty evidence in 13 RCTs (n = 383) (SMD, 0.30; 95% CI, 0.05-0.54) and self-reported function with low-certainty evidence in 3 RCTs (n = 85) (SMD, 0.38; 95% CI, -0.62 to 1.37). The evidence was downgraded by 2 levels for high risk of bias and imprecision for physical function and very serious imprecision for self-reported physical function. Conclusions and Relevance: In this systematic review and meta-analysis, PT was associated with a modest improvement in physical function compared with traditional strength training in healthy, community-living older adults. However, high-quality, larger RCTs are required to draw more definitive conclusions.

Longitudinal association between cardiometabolic comorbidities and physical activity in middle aged and older adults living with HIV.

OBJECTIVES: Cardiometabolic comorbidities have been associated with lower levels of physical activity (PA) among people living with HIV (PLWH). However, little is known about the longitudinal relationship between cardiometabolic comorbidities and PA participation. Therefore, the aim of this study was to determine the longitudinal association between cardiometabolic comorbidities and PA in PLWH. METHODS: PLWH from New York City and with complete PA and cardiometabolic comorbidity data between December 2016 and October 2020 were included. PA was evaluated using energy expenditure from the Minnesota Leisure Time Physical Activity Questionnaire (MLTPAQ). Body composition was measured using body mass index (BMI) and different waist circumference measures. Diabetes and hyperlipidemia were determined by physician diagnosis. Hemoglobin A1c (HbA1c) was evaluated through blood samples. Linear mixed-effects models analyses were conducted to assess the longitudinal relationship between cardiometabolic comorbidities and PA. RESULTS: A total of 164 participants (mean age 59.6 years; 48.2% females) were included. The mean follow-up period was 22.7 months (SD = 7.9). Higher BMI was associated with lower levels of PA in kcals/week (p < .05). An obese BMI was associated with lower levels of physical activity in kcals/week (p < .05). Higher mid-waist and umbilical circumference were associated with lower levels of PA in kcals/week (p < .05). Having hyperlipidemia was associated with lower levels of PA in kcals/week (p < .01). Having a diabetes diagnosis and elevated HbA1c were also associated with lower levels of PA in kcals/week (p < .05). CONCLUSION: Cardiometabolic comorbidities can have repercussions on PA participation among PLWH, which can in turn increase the risk of cardiovascular disease and mortality.

Validity, reliability, and measurement error of a sit-to-stand power test in older adults: A pre-registered study.

OBJECTIVES: Lower body power declines with age and is associated with decreased physical function in older adults. However, the majority of the tools available to measure power are expensive and require considerable space and expertise to operate. The purpose of this study was to assess the validity, reliability, and measurement error of a sit-to-stand power test (STSp) to assess lower body power. METHODS: 51 community-dwelling adults, 65 years or older, completed a power test using a pneumatic leg press (LP), the Short Physical Performance Battery (SPPB) that includes a test of balance, usual walking speed, and chair stand tests; Timed Up and Go (TUG) test at both usual and fast paces, and Patient-Reported Outcome Measures (PROMs). A two-week test-retest assessed the reliability in 36 participants. The study hypotheses and analysis were pre-registered prior to data collection and statistical analyses were blinded. RESULTS: The mean age was 71.3 years, with 63% females, and an average SPPB score of 10.6 (median = 12). STSp peak power was strongly correlated with LP (r = 0.90, 95% CI (0.82, 0.94). As hypothesized, the STSp peak power showed similar or higher correlations with physical function tests relative to LP peak power: SPPB (0.41 vs. 0.29), chair stand test (-0.44 vs. -0.35), TUG test at usual pace (-0.37 vs. -0.29) and fast pace (-0.41 vs. -0.34) and balance (0.33 vs. 0.22), but not for mobility (0.34 vs. 0.38) and function (0.41 vs. 0.48) questionnaire. For discriminant validity, as hypothesized, males showed higher STSp peak power compared to females (Δ = 492 W, p < .001, Cohen's d = 2.0). Test-retest assessment yielded an intraclass correlation coefficient of 0.96 and a standard error of measurement of 70.4 W. No adverse events were reported or observed for both tests. CONCLUSION: The STSp showed adequate validity and reliability in measuring lower body power in community-dwelling older adults. The test is quick, relatively inexpensive, safe, and portable and thus should be considered for use in aging research.

Association of Fish Oil and Physical Activity on Mobility Disability in Older Adults.

PURPOSE: This study aimed to examine whether long-term fish oil (FO) supplementation is associated with a lower risk of mobility disability and enhances benefits of physical activity (PA). METHODS: A total of 1635 sedentary adults age 70 to 89 yr from the Lifestyle Interventions and Independence for Elders single-blinded randomized, multicenter clinical trial, which compared a structured PA program to a health education program. Primary outcome was incident major mobility disability (MMD), defined by loss of ability to walk 400 m, measured every 6 months for an average of 2.6 yr. Secondary outcomes included persistent mobility disability, Short Physical Performance Battery, 400-m walk speed, and grip strength. RESULTS: A third of participants reported using FO at baseline (456 (28%); mean age, 78.5 yr; 70.5% women). MMD was experienced by 131 participants (28.7%) in the FO group and 405 (34.4%) participants in the nonuser group. After adjusting for confounders, FO supplementation was associated with a lower risk (HR, 0.78; 95% confidence interval (CI), 0.64-0.96) of incident MMD. However, there was no interaction (P = 0.19) between FO supplementation and PA intervention for MMD. For the secondary outcome of persistent mobility disability, the intervention association differed by supplementation (P = 0.002) with PA intervention associations of (HR, 1.36; 95% CI, 0.83-2.23) for users and (HR, 0.61; 95% CI, 0.46-0.81) for nonusers. Changes in physical performance outcomes were not modified by baseline FO supplementation or combination with PA. CONCLUSIONS: FO supplementation was associated with a lower risk of MMD in low to moderate functioning older adults. However, supplementation did not enhance the benefit of PA on risk of mobility disability. These results are hypothesis generating and need to be confirmed in randomized trials.

Cognitive Function as a Predictor of Major Mobility Disability in Older Adults: Results From the LIFE Study.

BACKGROUND AND OBJECTIVES: Many cross-sectional studies have confirmed a link between gait speed and cognitive function. However, it is unknown whether cognitive function plays a role in the onset of major mobility disability (MMD) and if the effects are independent of physical function. This study examined cognitive and physical function as predictors of MMD across an average of 2.6 years of follow-up in community-dwelling older adults with compromised mobility. RESEARCH DESIGN AND METHOD: Data were collected from 1,635 participants in the Lifestyle Interventions and Independence for Elders (LIFE) study ages 70-89 years free of MMD at baseline. MMD was assessed every 6 months and defined as the inability to walk 400 m in ≤15 min without assistance or sitting. Cognitive function was assessed at baseline, 18 months, and 24 months using a cognitive battery categorized into four domains: global cognitive function, processing speed, verbal memory, and executive function. RESULTS: Across the study duration of 2.6 years, 536 participants (32.8%) developed MMD. Cox Proportional Hazard models indicated a protective relationship for higher baseline processing speed (Hazard Ratio [HR] per standard deviation: 0.86, p = .006), executive function (HR: 0.86, p = .002), and global cognition (HR: 0.85, p = .001) on incidence of MMD adjusted for demographics, intervention, and comorbidities. Results were not significant after adjustment for gait speed. In adjusted longitudinal models, a positive change in processing speed was significantly associated with reduced risk of MMD (HR: 0.52, p < .001) while other domains were not. DISCUSSION AND IMPLICATIONS: In the LIFE study, processing speed at baseline and follow-up was a significant predictor of subsequent MMD although the observed association may be explained by physical function as reflected in gait speed. More studies are needed to understand how cognitive function, alone and in combination with physical function, influences risk of MMD.

Power training using pneumatic machines vs. plate-loaded machines to improve muscle power in older adults.

OBJECTIVES: Power training has been shown to be more effective than conventional resistance training for improving physical function in older adults; however, most trials have used pneumatic machines during training. Considering that the general public typically has access to plate-loaded machines, the effectiveness and safety of power training using plate-loaded machines compared to pneumatic machines is an important consideration. The purpose of this investigation was to compare the effects of high-velocity training using pneumatic machines (Pn) versus standard plate-loaded machines (PL). METHODS: Independently-living older adults, 60years or older were randomized into two groups: pneumatic machine (Pn, n=19) and plate-loaded machine (PL, n=17). After 12weeks of high-velocity training twice per week, groups were analyzed using an intention-to-treat approach. Primary outcomes were lower body power measured using a linear transducer and upper body power using medicine ball throw. Secondary outcomes included lower and upper body muscle muscle strength, the Physical Performance Battery (PPB), gallon jug test, the timed up-and-go test, and self-reported function using the Patient Reported Outcomes Measurement Information System (PROMIS) and an online video questionnaire. Outcome assessors were blinded to group membership. RESULTS: Lower body power significantly improved in both groups (Pn: 19%, PL: 31%), with no significant difference between the groups (Cohen's d=0.4, 95% CI (-1.1, 0.3)). Upper body power significantly improved only in the PL group, but showed no significant difference between the groups (Pn: 3%, PL: 6%). For balance, there was a significant difference between the groups favoring the Pn group (d=0.7, 95% CI (0.1, 1.4)); however, there were no statistically significant differences between groups for PPB, gallon jug transfer, muscle muscle strength, timed up-and-go or self-reported function. No serious adverse events were reported in either of the groups. CONCLUSIONS: Pneumatic and plate-loaded machines were effective in improving lower body power and physical function in older adults. The results suggest that power training can be safely and effectively performed by older adults using either pneumatic or plate-loaded machines.

The development and examination of a new walking executive function test for people over 50years of age.

A reduction in executive function (EF) performance is a major factor associated with the loss of functional independence among older adults. Computer-based tests are commonly used to evaluate EF; however, these mouse or keyboard tests are upper limb dominant while most activities of daily living (ADL, e.g. crossing a street) are lower limb dominant. The purpose of this study was to examine the utility of a newly developed walking EF test called the Walking Response and Inhibition Test (WRIT). The WRIT was validated by comparing its results a number of established computer-based tests and to an ADL-related test known to require EF, the Timed "Up & Go" Test (TUG). Fifty healthy adults, ranging in age from 50 to 86years (mean±SD, 65.5±9.6y) were evaluated using the WRIT, three computer-based EF tests, the TUG, a verbal memory test and an agility test. All computer-based EF tests were positively correlated to the WRIT (p<0.05); however, regression analyses revealed that the WRIT explained 37.5% of the variance in the TUG, while a composite of traditional computer-based tests explained 10.5%. As indicated by Lin's Concordance reliability (pc=0.82) between testing days was high and was supported by a Cronbach's alpha of 0.90. Bland-Altman analyses also demonstrated good agreement between the testing days with a small mean difference 3.48 (-3.71, 10.67). These results support the validity and reliability of the WRIT, and indicate that when assessing EF as it relates to functionality, the WRIT test may be a more appropriate measure than existing computer-based mouse and keyboard tests.

Functional strength training: Seated machine vs standing cable training to improve physical function in elderly.

BACKGROUND: The majority of the strength training studies in older adults have incorporated fixed-form exercises using seated resistance training machines. In light of the modest improvements in physical function shown in these studies, functional or task-specific exercises, involving movement patterns that mimic daily activities, have been studied. Free-form exercises, using free-weights or cable, is another form of functional strength training. Currently, no intervention studies exist comparing free-form exercises, using cable machines, and fixed-form exercises, using seated machines in older adults. METHODS: A total of 29 independently-living older adults, 65years or older, were randomized into two groups, seated machine (SM, n=10) and standing cable (SC, n=12). After 12weeks of training twice per week, groups were compared. The primary outcome was the Physical Performance Battery (PPB), a measure of physical function. Secondary outcomes were lower and upper body strength and power, activities of daily living evaluated by multiple tests including: Physical Performance Test (PPT), pan carry and gallon jug transfers, ratings of perceived exertion (RPE), and self-reported function using Patient Reported Outcomes Measurement Information System (PROMIS). Outcome assessors were blinded to participants' intervention assignments. RESULTS: The PPB (SC=0.23 points; SM=0.15 points) showed clinical and significant improvements, but there was no significant difference between the groups (g=0.2, 95% CI (-0.6, 1.0). For secondary outcomes, chair stand (g=0.7, 95% CI (0.2, 1.6), p=0.03) and pan carry (g=0.8, 95% CI (0.07, 1.07), p=0.04) favored SC, while chest press 1RM (g=0.2, 95% CI (0.06, 1.1), p=0.02) favored SM. There were no statistically significant group differences between PPB, gallon jug transfer, leg press 1RM, power, RPE or self-reported function. CONCLUSIONS: Standing cable training was not superior to seated machine training in improving physical performance in older adults. However, both training interventions were effective in improving function. The findings also suggest that exercise specificity should be considered when prescribing resistance exercises to improve physical function in older adults.

Validity and reliability of a video questionnaire to assess physical function in older adults.

BACKGROUND: Self-report questionnaires are widely used to assess physical function in older adults. However, they often lack a clear frame of reference and hence interpreting and rating task difficulty levels can be problematic for the responder. Consequently, the usefulness of traditional self-report questionnaires for assessing higher-level functioning is limited. Video-based questionnaires can overcome some of these limitations by offering a clear and objective visual reference for the performance level against which the subject is to compare his or her perceived capacity. Hence the purpose of the study was to develop and validate a novel, video-based questionnaire to assess physical function in older adults independently living in the community. METHODS: A total of 61 community-living adults, 60years or older, were recruited. To examine validity, 35 of the subjects completed the video questionnaire, two types of physical performance tests: a test of instrumental activity of daily living (IADL) included in the Short Physical Functional Performance battery (PFP-10), and a composite of 3 performance tests (30s chair stand, single-leg balance and usual gait speed). To ascertain reliability, two-week test-retest reliability was assessed in the remaining 26 subjects who did not participate in validity testing. RESULTS: The video questionnaire showed a moderate correlation with the IADLs (Spearman rho=0.64, p<0.001; 95% CI (0.4, 0.8)), and a lower correlation with the composite score of physical performance tests (Spearman rho=0.49, p<0.01; 95% CI (0.18, 0.7)). The test-retest assessment yielded an intra-class correlation (ICC) of 0.87 (p<0.001; 95% CI (0.70, 0.94)) and a Cronbach's alpha of 0.89 demonstrating good reliability and internal consistency. CONCLUSIONS: Our results show that the video questionnaire developed to evaluate physical function in community-living older adults is a valid and reliable assessment tool; however, further validation is needed for definitive conclusions.

Comparative Effect of Power Training and High-Speed Yoga on Motor Function in Older Patients With Parkinson Disease.

OBJECTIVES: To compare the effects of power training (PWT) and a high-speed yoga program on physical performances in older patients with Parkinson disease (PD), and to test the hypothesis that both training interventions would attenuate PD symptoms and improve physical performance. DESIGN: Randomized controlled trial. SETTING: A laboratory of neuromuscular research and active aging. PARTICIPANTS: Patients with PD (N=41; mean age ± SD, 72.2 ± 6.5y). INTERVENTIONS: Two high-speed exercise interventions (specifically designed yoga program and PWT) were given for 12 weeks (twice a week), and 1 nonexercise control group. MAIN OUTCOME MEASURES: Unified Parkinson Disease Rating Scale motor score (UPDRSMS), Berg Balance Scale (BBS), Mini-Balance Evaluation Systems Test (Mini-BESTest), Timed Up and Go, functional reach, single leg stance (SLS), postural sway test, 10-m usual and maximal walking speed tests, 1 repetition maximum (RM), and peak power (PPW) for leg press. RESULTS: For the posttests, both training groups showed significant improvements (P<.05) in all physical measurements except functional reach on the more affected side, SLS, and postural sway compared with the pretests, and significantly better scores for UPDRSMS, BBS, Mini-BESTest, Timed Up and Go, functional reach on the less affected side, 10-m usual and maximal walking speed tests, 1RM, and PPW than controls, with no differences detected between the yoga program and PWT. CONCLUSIONS: Both the specially designed yoga program and PWT programs can significantly improve physical performance in older persons with PD.

Lower-Body Torque and Power Declines Across Six Decades in Three Hundred Fifty-Seven Men and Women: A Cross-sectional Study With Normative Values.

This study presents age-specific and gender-specific patterns and normative values for lower-body isokinetic performance in 195 women and 162 men, 18-80 years of age, using data collected from 1991 to 2004. Peak torque (PT) and average power (AP) during knee extension (KE), knee flexion (KF), ankle plantar flexion, and dorsiflexion (DF) at 1.05, 3.14, and 5.24 rad · s(-1) were compared by decade. Knee extension and KF at all speeds showed a significant main effect by age group (G). Men's KEPT and KEAP at 60 and 70 G were significantly different than 20, 30, and 40 G at all speeds. Additionally, 50 G differed from all other groups. For women, 50, 60, and 70 G KEPT and KEAP at 5.24 rad · s (-1)differed significantly from all other age groups. Men's KFPT and KFAP showed no differences among 20, 30, and 40 G, whereas 50 G differed from all groups except 60 G. For KFPT and KFAP, women 20 and 30 G differed from other age groups at all testing speeds. Plantar flexion and DF performance declines were speed specific mainly occurring at 3.14 rad · s.(-1) The results reflect declines in strength and power beginning during the fifth decade in men, and earlier in women. The study also provides normative values, which may be used to evaluate neuromuscular performances by gender across decades of life.

Power training induced change in bradykinesia and muscle power in Parkinson's disease.

UNLABELLED: Power-based resistance training (PWT), using low load and high velocity, can improve physical function and quality of life in older persons. Patients with Parkinson's disease (PD), exhibiting muscular weakness and reduced movement speed, have been shown to be benefit from resistance training; however, little is known about the advantages of PWT for PD. PURPOSE: To evaluate the effects of PWT on bradykinesia and muscular performance in older patients with PD. METHODS: Twenty-six patients with mild to moderate PD were randomly assigned to a PWT or control group (CON). The PWT program was three months, incorporating two sessions/wk of high-speed resistance training combined balance and agility drills. Outcome measures included: upper and lower limb bradykinesia scores, one repetition maximums (1RM) and peak powers on biceps curl, chest press, leg press, hip abduction and seated calf, and quality of life (PDQ-39). RESULTS: The PWT group produced significant improvement in both upper and lower limbs bradykinesia scores, 1RM and muscle peak power (p < .05), which surpassed the CON group except for power during the seated calf exercise. No significant correlations between changes in clinical measure of bradykinesia and muscle peak power were observed after training. Significant improvements were seen in the PDQ-39 overall score, subsections for mobility, activities of daily living and social support for the PWT group. CONCLUSION: The 3-month PWT program significantly reduced bradykinesia and increased muscle strength and power in older patients with PD. Power training is an effective training modality to improve physical function and quality of life for PD.

High-speed circuit training vs hypertrophy training to improve physical function in sarcopenic obese adults: a randomized controlled trial.

BACKGROUND: Progressive loss of muscle and strength with age is often coincident with increases in adiposity, leading to a condition called sarcopenic obesity. Studies have shown sarcopenic obese adults to be at higher risk for declines in physical function. Despite this rising public health concern, no intervention studies currently exist in this population. METHODS: A total of 21 sarcopenic obese adults, 60 years or older, were randomized into two groups, strength/hypertrophy (SH, n=9) and high-speed circuit (HSC, n=8) and were trained for 15 weeks. The primary outcome was the SPPB modified as a measure of physical function, assessed by assessors blinded to randomization. Secondary outcomes were lower body and upper body power and strength, instrumental activities of daily living (IADL), ratings of perceived exertion (RPE), body fat % (BF%), skeletal muscle index (SMI), and grip strength (GRP). RESULTS: For the SPPB results favored HSC over SH (1.1, 95% CI (-.1 to 2.4), p=.08) and showed a moderate effect size (Hedge g=0.6, 95% CI (-0.4, 1.6)). For secondary outcomes, lower body power (mean difference=158 W, 95% CI (2, 315); p=.01) and RPE (mean difference=-1.5, 95% CI (-2.9, -0.12); p=.04) also favored HSC. IADL, SMI, BF%, upper and lower body strength and upper body power, showed no statistically significant differences between groups. CONCLUSIONS: Considering the moderate effect size, the large treatment effect shown by the upper limit of the 95% CI, the low perceived exertion, and no adverse effects, HSC training should be further investigated with a larger sample size in sarcopenic obese adults.