Effect of Dietary Cholesterol on Blood Biomarkers during Resistance Training: Randomized Controlled Trial

Abstract

To examine possible explanations for the observation that cholesterol is positively associated to skeletal muscle responses to resistance training, a randomized, double blind placebo controlled trial of dietary cholesterol administration during 12 weeks of resistance exercise training (RET, 3x/week, 2‐3 sets, 8–12 reps, 70% of max strength) in 50–65 year old generally healthy men and women was conducted. Fasting acute and chronic blood samples were collected to determine the association of the cholesterol administration and changes in blood biomarkers of select anabolic hormones, and inflammatory and metabolic markers that may help explain muscle responsiveness to cholesterol. Groups consumed either 3.5 mg/kg lean/day (<200 mg/day, LC, N=9), 7.0 mg/kg lean/day (~400 mg/day, MC, N=9), or 14.0 mg/kg lean/day (~800 mg/day, HC, N=9) of cholesterol via egg powder dissolved in a chocolate flavored food. Dietary cholesterol did not alter resting or mean testosterone (LC=5.5±0.9, MC=4.8±1.0, HC=2.9±1.1 ng/ml) but was positively associated to responsiveness to acute RET. Resting C reactive protein, insulin, cortisol, glucose, and c‐peptide were unaffected by RET or cholesterol. Though cholesterol is associated to muscle responsiveness RET, blood biomarkers do not provide sufficient clarification of the potential mechanism.