A Pilot Study Examining the Effects of 8-Week Whey Protein versus Whey Protein Plus Creatine Supplementation on Body Composition and Performance Variables in Resistance-Trained Women.

ABSTRACT

AIMS: We performed a pilot study examining the effects of whey protein and creatine supplementation (PRO + CRE group) versus whey protein supplementation (PRO group) alone on body composition and performance variables in a limited number of resistance-trained women. METHODS: Seventeen resistance-trained women (21 ± 3 years, 64.7 ± 8.2 kg, 23.5 kg/m2, 26.6 ± 4.8% body fat, >6 months of training) performed a 4-day per week split-body resistance training program for 8 weeks. Subjects ingested either 24 g PRO (n = 9) or 24 g whey plus 5 g creatine monohydrate (PRO + CRE, n = 8) following each exercise bout. At baseline (T1), 4 weeks (T2) and 8 weeks (T3), body composition was measured by dual X-ray absorptiometry (DXA), strength measures (leg press and bench press one repetition maximum) and lower-body power measures were determined. RESULTS: DXA lean mass increased from T1 to T3 in both groups (PRO +2.5 kg, p < 0.001; PRO + CRE +2.5 kg, p < 0.001), although no differences between groups were observed. Compared to T1 values, performance measures similarly increased in both groups from T1 to T3 although, no between-group differences were observed. CONCLUSIONS: PRO + CRE did not enhance training adaptations compared to PRO, albeit studies employing longer-term interventions with larger sample sizes are needed in order to confirm or disprove our findings.