The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength

Our purpose was to assess muscular adaptations during 6 weeks of resistance training in 36 males randomly assigned to supplementation with whey protei n (W; 1.2 g/kg/day), whey protein and creatine monohydrate (WC, 0.1 g/kg/da y), or placebo (P; 1.2 g/kg/day maltodextrin). Measures included lean tissu e mass by dual energy x-ray absorptiometry, bench press and squat strength (1-repetition maximum), and knee extension/flexion peak torque. Lean tissue mass increased to a greater extent with training in WC compared to the oth er groups, and in the W compared to the P group (p < .05). Bench press stre ngth increased to a greater extent for WC compared to W and P (p < .05). Kn ee extension peak torque increased with training for WC and W (p < .05), bu t not for P. All other measures increased to a similar extent across groups . Continued training without supplementation for an additional 6 weeks resu lted in maintenance of strength and lean tissue mass in all groups. Males t hat supplemented with whey protein while resistance training demonstrated g reater improvement in knee extension peak torque and lean tissue mass than males engaged in training alone. Males that supplemented with a combination of whey protein and creatine had greater increases in lean tissue mass and bench press than those who supplemented with only whey protein or placebo. However, not all strength measures were improved with supplementation, sin ce subjects who supplemented with creatine and/or whey protein had similar increases in squat strength and knee flexion peak torque compared to subjec ts who received placebo.