The Effects Of Creatine And Blood Flow Restriction On Strength And Body Composition In Women

PURPOSE: A limiting factor of BFR training may be the early onset of fatigue. Creatine monohydrate (Cr) is a supplement which aids in energy production, aids in fatigue and elicits favorable strength gains. There is some hesitancy from women to utilize creatine in fear of gaining weight. Therefore, the purpose of this investigation was to examine the effects of creatine supplementation and/or BFR on muscle among women across 8 weeks of resistance training. METHODS: Fifty-nine (mean ± SD; 21.6 ± 3.1 years; 163.7 ± 6.2 cm; 62.9 ± 25.7 kg) females volunteered for a double blind, placebo controlled, randomized training study. Training visits consisted of three lower body exercises (leg press, leg extension, and leg curl) performed twice a week for eight weeks. Exercise was performed with BFR (60% of total arterial occlusion pressure; 1 × 30, 3 × 15, 30% of 1 repetition maximum [1RM]),) or without BFR. Measurements of concentric peak torque (CPT), body mass (BM), total body water (TBW), intra-cellular fluid (ICF), extra-cellular fluid (ECF), muscle thickness (MT) and cross-sectional area (CSA) were assessed at baseline, post-loading (5 days later), 4 weeks, and post-test. Separate repeated measures ANOVAs were used to examine changes in MVIC, BM, MT, CSA, TBW, ICF, and ECF. RESULTS: There was no significant (p = 0.015- 0.63) Time x Group interaction for MT, CSA, BF, TBW, or ICF. There were however, significant main effects for Time for measures of MT (p < 0.001) and CSA (p < 0.001). Specifically, MT increased by 2.9% from post-loading (2.28 ± 0.04 cm) to 8wk (2.35 ± 0.04 cm), while CSA increased by 4.1% from baseline (9.8 ± 0.3cm2) to 8wk (10.2 ± 0.3cm2). Furthermore, there was a significant (p = 0.013) Time x Group interaction for CPT. Analyses of simple main effects indicated that there were significant increases in the BFR-Cr (15.7%), BFR-Pl (12.7%), and Cr (10.6%) groups. CONCLUSIONS: The results of the present study indicated there were similar increases in MT and CSA regardless of training and supplementation. However, regarding concentric strength, there were greater increases for the BFR and creatine supplementation groups. Overall, resistance exercise, BFR and Cr can be used independently or together to induce positive muscular adaptations among women. Supported by: NSCA Doctoral Student Grant