Differences In Male Vs Female Regional Body Composition Changes With Resistance Training

PURPOSE: The purpose of this study is to analyze the effects of resistance training on regional body composition in normal-weight males and females. METHODS: A total of 31 (n=14 males) young volunteers were randomized to intervention (9 females, 7 males) and control groups (8 females, 7 males). Females had a body mass index (BMI) of 22.6±1.95 kg/m2, and percentage of body fat (%BF) of 32.3±7.8 %; males had a BMI of 22.95±1.55 kg/m2 and %BF of 18.14±6.22%. Body composition measurements were recorded using a dual-energy X-ray absorptiometry (DXA), and a maximal strength test was used on both upper and lower body at pre and post intervention. Left and right trunk, arms, and legs lean body mass (LBM) and body fat (BF) were recorded and percentage of change (%∆) was calculated for each variable. The resistance training protocol consisted of 3 sessions per week for 3 weeks, using 7 exercises (i.e. bench press, barbell back squats, leg press, sit-ups, dead lifts, barbell rows, and jump squats) consisting of 10 repetitions per exercise for 3 sets. RESULTS: Non-parametric tests showed a statistically significant difference in exercising males (p=0.001) in left leg %∆LBM (3.05±1.68%) when compared to controls (-2.32±2.14%). No statistically significant differences were found in any of the body composition variables for females in the resistance training group compared to the control group. CONCLUSIONS: Our results suggest that males and females exhibit different regional body composition changes in response to the same resistance training program. Further research is needed to increase the understanding of sex-related differences in resistance training-induced regional body composition changes.