Cribb, Paul J and Hayes, Alan ORCID: 0000-0003-1398-3694 (2006) Effects of Supplement-Timing and Resistance Exercise on Skeletal Muscle Hypertrophy. Medicine & Science in Sports & Exercise, 38 (11). pp. 1918-1925. ISSN 0195-9131, 1530-0315

Abstract

PURPOSE: Some studies report greater muscle hypertrophy during resistance exercise (RE) training from supplement-timing (i.e., the strategic consumption of protein and carbohydrate before and/or after each workout). However, no studies have examined whether this strategy provides greater muscle hypertrophy or strength development compared to supplementation at other times during the day. Therefore, the purpose of this study was to examine the effects of supplement-timing compared to supplementation in the hours not close to the workout on muscle fiber hypertrophy, strength and body composition during a 10 week RE program. METHODS: In a double-blind, randomized protocol, resistance-trained males were matched for strength and placed into one of two groups; PRE-POST consumed a supplement (1g/kg/body wt) containing protein/creatine/glucose immediately before and after RE. The MOR-EVE group consumed the same dose of the same supplement in the morning and late evening. All assessments were completed the week before and after 10 weeks of structured, supervised RE training. Assessments included strength (1RM, three exercises), body composition (DEXA) and vastus lateralis muscle biopsies for determination of muscle fiber type (I, IIa, IIx) cross-sectional area (CSA), contractile protein, creatine (Cr) and glycogen content. RESULTS: PRE-POST demonstrated a greater (P < 0.05) increase in lean body mass and 1RM strength in two of three assessments. The changes in body composition were supported by a greater (P < 0.05) increase in CSA of the type-II fibers and contractile protein content. PRE-POST supplementation also resulted in higher muscle Cr and glycogen values after the training program (P < 0.05). CONCLUSION: Supplement-timing represents a simple but effective strategy that enhances the adaptations that are desired from RE-training.

Search Google Scholar

Repository staff login