RESUMEN
OBJECTIVE: It is not known which laboratory indices of muscle mass, strength or quality can distinguish functional performance in healthy middle aged women. The aim of this study was to (a) examine the association between upper leg lean tissue mass, knee extensor strength, muscle quality (strength per unit lean tissue mass) and functional performance and (b) to determine the utility of tertiles of muscle strength and muscle quality to distinguish gradations of functional capacity in healthy 50-70y women. METHODS: Using a cross-sectional study design, one hundred and twenty-eight healthy 50-70y women (mean age: 60.4, SD=5.1y) underwent body composition assessment (dual X-ray absorptiometry) and performed maximal voluntary isometric contractions of the knee extensors (Con-Trex Dynamometer). Functional performance was assessed using a 5 repetition and 30s chair rise test and 900m gait speed test. RESULTS: Ordered by muscle strength or muscle quality, those in the highest tertile (T1) demonstrated greater functional performance than those in lowest tertile (T3). There was no association between upper leg lean tissue mass and functional performance (r=≤0.06). Muscle strength explained a greater proportion of the variance in all functional performance measures relative to muscle quality (R2=0.13-0.36 vs. R2=0.11-0.16). CONCLUSION: Upper leg lean tissue mass is not associated with physical performance in healthy 50-70y women. These results suggest strength relative to the body mass being accelerated distinguishes gradations in functional performance better than muscle quality healthy 50-70y women.
Asunto(s)
Absorciometría de Fotón/métodos , Composición Corporal/fisiología , Fuerza Muscular , Adulto , Estudios Transversales , Femenino , Humanos , Fuerza Muscular/fisiologíaRESUMEN
OBJECTIVES: We compared Black West Indian immigrants' and US-born Blacks' sexual and drug-use risk behaviors and their beliefs related to using condoms and informing partners of sexually transmitted infections (STIs) to identify possible differences in risk. METHODS: We drew data from the baseline assessment of a clinic-based intervention designed to increase partner STI notification. RESULTS: Black West Indian men were less likely than were US-born Black men to report nonregular partners. There were no differences in condom use. US-born Black women were more likely than were Black West Indian women to be extremely confident that they could convince their regular partners to use condoms (odds ratio [OR] = 2.40; 95% confidence interval [CI] = 1.21, 4.76), whereas there were no differences between Black West Indian and US-born Black men on this measure (interaction P = .06). US-born Black women were more likely than were Black West Indian women to be extremely confident in their ability to discuss STI screening with their regular partners (OR = 1.89; 95% CI = 1.03, 3.47). CONCLUSIONS: Black West Indian women's lower levels of confidence that they can discuss STI screening with their regular partners and convince these partners to use condoms may increase their infection risk. Gender-sensitive interventions are warranted for Black West Indian immigrants, especially women.