B-18 Free Communication/Slide - Resistance Training: MAY 28, 2008 1:00 PM - 3:00 PM ROOM: 122
PURPOSE: To examine the influence of sex and race on the effects of strength training (ST) on thigh muscle volume (MV), mid-thigh subcutaneous fat (SCF) and intermuscular fat (IMF).
METHODS: One hundred and eighty-one previously inactive healthy Caucasian (N=117) and African-American (N=54) men (N=82) and women (N=99), aged 50-85 yrs, underwent ~10 weeks of unilateral knee extension ST. Quadriceps MV and midthigh SCF and IMF cross-sectional area were measured with computed tomography before and after ST. Sex and race comparisons were made with a 2 x 2 (sex by race) analysis of covariance.
RESULTS: Training-induced increases in absolute MV were significantly greater (P < 0.001) in men than in women, though both sex groups increased MV significantly with ST (P < 0.001) and the relative (%) increases were similar. There were significant increases in MV within race groups (P < 0.001); but no significant differences between races. There were no significant changes in SCF or IMF whether sex and racial groups were separated or combined. In addition, there was no sex by race interaction for changes in MV, SCF, or IMF with ST.
CONCLUSIONS: Strength training does not alter subcutaneous or intermuscular fat regardless of sex or racial differences. Although men exhibit a greater muscle hypertrophic response to strength training compared to women, the difference is small. Race does not influence this response.
This study was supported by Grants #AG-018336 and AG-000268 from the National Institute on Aging.