Dietary Cholesterol and Skeletal Muscle Hypertrophy with Resistance Training: A Randomized Placebo-Controlled Trial
Background:We recently reported a strong positive association of dietary cholesterol and skeletal muscle responses to resistance training (Riechman, 2007). To confirm these findings we conducted a randomized placebo controlled trial in which we supplemented the diet with whole egg or egg white (control).Methods:3 groups of 50–69 year old generally healthy subjects (N=30) underwent 12 weeks of resistance exercise training (RET, 3x/week, 2–3 sets, 8–12 reps, 70% of max strength). Each group consumed 3.5 mg/kg lean/day (<200 mg/day, LC), 7.0 mg/kg lean/day (∼400 mg/day, MC), or 14.0 mg/kg lean/day (∼800 mg/day, HC) of cholesterol. Subjects were asked to complete 48 food records over the 12 wks to confirm dietary compliance. Body composition (DEXA) and maximal strength tests were conducted before and after the training.Results:Summary strength gain (chest press +leg press) was increased significantly (P<0.05) with increasing dietary cholesterol (HC=52±8%, MC=38±8%, LC=21±8%). The mean gain in lean mass was 1.7±1.0 kg (3.7%) where subjects also lost 0.5±1.7 kg of fat mass (1.6%). Changes in lean mass and fat mass between groups was not significantly different (P>0.05).Conclusion:Our results confirm our previous finding that high dietary cholesterol contributes to strength gain with resistance training; however, lean mass gains were inconsistent.
