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Purpose: The optimal intensity of resistance training (RT) to improve muscular, physical performance, and metabolic adaptations still needs to be well established for older adults. Based on current position statements, we compared the effects of two different RT loads on muscular strength, functional performance, skeletal muscle mass, hydration status, and metabolic biomarkers in older women. Methods: One hundred one older women were randomly allocated to perform a 12-wk whole-body RT program (eight exercises, three sets, three nonconsecutive days a week) into two groups: 8-12 repetitions maximum (RM) and 10-15RM. Muscular strength (1RM tests), physical performance (motor tests), skeletal muscle mass (dual-energy X-ray absorptiometry), hydration status (bioelectrical impedance), and metabolic biomarkers (glucose, total cholesterol, HDL-c, HDL-c, triglycerides, and C-reactive protein) were measured at baseline and posttraining. Results: Regarding muscular strength, 8-12RM promoted higher 1RM increases in chest press (+23.2% vs +10.7%, P < 0.01) and preacher curl (+15.7% vs +7.4%, P < 0.01), but not in leg extension (+14.9% vs +12.3%, P > 0.05). Both groups improved functional performance (P <0.05) in gait speed (4.6%-5.6%), 30 s chair stand (4.6%-5.9%), and 6 min walking (6.7%-7.0%) tests, with no between-group differences (P > 0.05). The 10-15RM group elicited superior improves in the hydration status (total body water, intracellular and extracellular water; P < 0.01), and higher gains of skeletal muscle mass (2.5% vs 6.3%, P < 0.01), upper (3.9% vs 9.0%, P < 0.01) and lower limbs lean soft tissue (2.1% vs 5.4%, P < 0.01). Both groups improved their metabolic profile. However, 10-15RM elicited greater glucose reductions (-0.2% vs -4.9%, P < 0.05) and greater HDL-c increases (-0.2% vs +4.7%, P < 0.01), with no between-group differences for the other metabolic bio-markers (P > 0.05). Conclusions: Our results suggest that 8-2RM seems more effective than 10-15RM for increasing upper limbs' muscular strength, whereas the adaptative responses for lower limbs and functional performance appear similar in older women. In contrast, 10-15RM seems more effective for skeletal muscle mass gains, and increased intracellular hydration and improvements in metabolic profile may accompany this adaptation. [ABSTRACT FROM AUTHOR]

Background and purpose: There is a growing body of evidence indicating that phase angle (PhA) can be used as an indicator of nutritional status, disease prognosis, and mortality risk; however, it is still unknown whether PhA can be used as an explanator of functional capacity and muscle quality in older women. The main purpose of this cross-sectional study was to explore whether PhA is associated with muscle quality and functional capacity in older women, regardless of total and regional body composition. Methods: A total of 125 older women-66.7 (4.7) years; 65.6 (10.9) kg body mass; 156.1 (5.2) cm height; 26.9 (4.0) kg/m body mass index-participated in this study. Anthropometric, PhA, body composition (whole-body dual-energy x-ray absorptiometry) and muscle quality (defined as total muscular strength per kilogram of appendicular lean soft tissue) were measured. The functional capacity was assessed by 4 tests: 10-m walk test, rising from sitting position, rising from ventral decubitus position, and rising from a chair and walking around the house. The summing z-scores for the 4 tests was used as a continuous functional capacity score. Linear regression analysis was conducted to test whether PhA is related to the dependent variables (muscle quality and functional capacity), after adjusting for potential covariates. Results: The PhA presented a small-to-moderate relationship with muscle quality (r = 0.27; P < .01) and functional capacity (r = 0.31; P < .01), respectively. These relationships remained significant after adjustment for age, lower limb lean soft tissue, and total fat mass for muscle quality (β= 0.55; P < .01) and functional capacity (β= 1.38; P < .01). Conclusion: Our findings suggest that healthy elderly women with higher values of PhA have a better muscle quality and functionality, regardless of age and body composition. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of resistance training (RT) performed in a pyramid (PR) vs. constant (CT) load system on muscular strength and hypertrophy in resistance-trained older women. Thirty-three older women (69.7 ± 5.9 years, 69.1 ± 15.0 kg, 156.6 ± 6.2 cm, and 28.1 ± 5.4 kg⋅m-2) were randomized into 2 groups: one that performed RT with a CT load (n = 16) and another group that performed RT in an ascending PR fashion (n = 17). Outcomes included 1 repetition maximum (RM) tests and assessment of skeletal muscle mass estimated by dual-energy X-ray absorptiometry. The study lasted 32 weeks, with 24 weeks dedicated to preconditioning and 8 weeks for the actual experiment. The RT program was conducted 3 d⋅wk-1; the CT consisted of 3 sets of 8-12RM with same load across sets, whereas the PR consisted of 3 sets of 12/10/8RM with incremental loads for each set. A significant (p ≤ 0.05) change from pretraining to posttraining was observed for chest press total strength (CT: pre = 122.8 ± 21.0 kg, post = 128.9 ± 21.4 kg, effect size [ES] = 0.28; PR: pre = 120.5 ± 22.8 kg, post = 125.8 ± 22.9 kg, ES = 0.24) and muscle mass (CT: pre = 21.4 ± 3.6 kg, post = 21.7 ± 3.5 kg, ES = 0.09; PR: pre = 20.9 ± 3.4 kg, post = 21.1 ± 3.4 kg, ES = 0.06) without differences between groups. Results suggest that both systems are effective to improve strength and muscle growth, but PR is not superior to CT for inducing improvements in previously trained older women. [ABSTRACT FROM AUTHOR]