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Objectives: To determine whether intervention‐induced physical activity (PA) changes in sedentary older adults differed according to dopamine‐related genotype. Design: Randomized clinical trial (Lifestyle Interventions and Independence for Elders Trial (2010–13)). Setting: Multicenter study, 8 U.S. locations. Participants: Volunteer sample of sedentary adults aged 70 to 89 at risk of disability (N=1635). Interventions: Structured PA versus health education (HE) for an average of 2.6 years. Measurements: Single‐nucleotide polymorphisms of dopamine‐related genes (dopamine receptor (DR) D1, DRD2, DRD3, and catechol‐O‐methyltransferase (COMT)) were assessed. Average moderate to vigorous PA (MVPA) was calculated using accelerometry (min/d) at baseline and 6, 12, and 24 months. Between‐arm MVPA differences according to genotype and genotype with square root–transformed MVPA separately according to arm were tested, stratified according to race, and adjusted for multiple comparisons. Results: White participants in the PA arm (n=513) had higher average square root transformed MVPA (4.91±1.91)than those in the HE arm (n=538) (4.51±1.82) (p=.001). Between‐arm differences were greater for DRD2 Met/Met (high dopamine; HE: 4.76±1.80, PA: 5.53±1.60, p=.03) than Val/Val (low dopamine; HE: 4.58±1.92, PA: 4.81±1.83, p=.16); results were similar for COMT. In the PA arm, DRD2 Met/Met was associated with higher average MVPA (5.39±2.00) than Met/Val (4.46±2.51) (p=.01) and Val/Val (4.65±2.71) (p=.01). There were no associations for other genes. Associations were not significant in blacks but followed similar trends. Conclusion: Higher dopamine signaling may support changes in PA during an intervention. The role of dopamine‐related pathways in promoting PA participation and enhancing response to interventions in sedentary older adults should be studied. Trial Registration: clinicaltrials.gov Identifier: NCT01072500 [ABSTRACT FROM AUTHOR]

Objectives To assess the effects of bimagrumab on skeletal muscle mass and function in older adults with sarcopenia and mobility limitations. Design A 24-week, randomized, double-blind, placebo-controlled, parallel-arm, proof-of-concept study. Setting Five centers in the United States. Participants Community-dwelling adults (N = 40) aged 65 and older with gait speed between 0.4 and 1.0 m/s over 4 m and an appendicular skeletal muscle index of 7.25 kg/m2 or less for men and 5.67 kg/m2 or less for women. Intervention Intravenous bimagrumab 30 mg/kg (n = 19) or placebo (n = 21). Measurements Change from baseline in thigh muscle volume (TMV), subcutaneous and intermuscular fat, appendicular and total lean body mass, grip strength, gait speed, and 6-minute walk distance (6MWD). Results Thirty-two (80%) participants completed the study. TMV increased by Week 2, was sustained throughout the treatment period, and remained above baseline at the end of study in bimagrumab-treated participants, whereas there was no change with placebo treatment (Week 2: 5.15 ± 2.19% vs −0.34 ± 2.59%, P < .001; Week 4: 6.12 ± 2.56% vs 0.16 ± 3.42%, P < .001; Week 8: 8.01 ± 3.70% vs 0.35 ± 3.32%, P < .001; Week 16: 7.72 ± 5.31% vs 0.42 ± 5.14%, P < .001; Week 24: 4.80 ± 5.81% vs −1.01 ± 4.43%, P = .002). Participants with slower walking speed at baseline receiving bimagrumab had clinically meaningful and statistically significantly greater improvements in gait speed (mean 0.15 m/s, P = .009) and 6MWD (mean 82 m, P = .022) than those receiving placebo at Week 16. Adverse events in the bimagrumab group included muscle-related symptoms, acne, and diarrhea, most of which were mild in severity and resolved by the end of study. Conclusion Treatment with bimagrumab over 16 weeks increased muscle mass and strength in older adults with sarcopenia and improved mobility in those with slow walking speed. [ABSTRACT FROM AUTHOR]

Objectives To determine effects of Sit 'N' Fit Chair Yoga, compared to a Health Education program ( HEP), on pain and physical function in older adults with lower extremity osteoarthritis ( OA) who could not participate in standing exercise. Design Two-arm randomized controlled trial. Setting One HUD senior housing facility and one day senior center in south Florida. Participants Community-dwelling older adults (N = 131) were randomly assigned to chair yoga (n = 66) or HEP (n = 65). Thirteen dropped after assignment but prior to the intervention; six dropped during the intervention; 106 of 112 completed at least 12 of 16 sessions (95% retention rate). Interventions Participants attended either chair yoga or HEP. Both interventions consisted of twice-weekly 45-minute sessions for 8 weeks. Measurements Primary: pain, pain interference; secondary: balance, gait speed, fatigue, functional ability measured at baseline, after 4 weeks of intervention, at the end of the 8-week intervention, and post-intervention (1 and 3 months). Results The chair yoga group showed greater reduction in pain interference during the intervention ( P = .01), sustained through 3 months ( P = .022). WOMAC pain ( P = .048), gait speed ( P = .024), and fatigue ( P = .037 ) were improved in the yoga group during the intervention ( P = .048) but improvements were not sustained post intervention. Chair yoga had no effect on balance. Conclusion An 8-week chair yoga program was associated with reduction in pain, pain interference, and fatigue, and improvement in gait speed, but only the effects on pain interference were sustained 3 months post intervention. Chair yoga should be further explored as a nonpharmacologic intervention for older people with OA in the lower extremities. Trial Registration: ClinicalTrials.gov: NCT02113410. [ABSTRACT FROM AUTHOR]