Document Type: Original Article
Department of Exercise physiology, Marvdasht branch, Islamic Azad University, Marvdasht, Iran
Education Administration in Shiraz
Introduction: Traditionally, resistance exercise stimulates growth hormone (GH) secretion and leads to muscle hypertrophy in a load-dependent manner; however, new research demonstrates that blood flow restricted resistance exercise (BFR) produces potent GH responses that are similar to or exceed those produced following high-load resistance exercise. The purpose of the present study was to examine the effects of BFR resistance exercise versus traditional resistance training (TRT) on GH levels and thigh muscle cross-sectional area (CSA).
Material & Methods: Twenty untrained healthy men volunteered to participate in this study. The subjects were divided into BFR resistance exercise group (4 sets with 20-50 % of 1-RM in each station with 30-60 second of rest) or TRT group (4 sets with 6-12 maximal repetitions at 70-80% of 1-RM in each station with 2-3 minute of rest) randomly. All the subjects executed five resistance exercises selected to stress the thigh muscle groups in the following order: leg press, squat, leg extension, prone leg curl, and dead lift. BFR resistance exercise and TRT consisted of 50-60 min of station weight training per day, 3 days a week, for 8 weeks. Thigh muscle CSA and GH concentration were measured before and after the intervention.
Results: The results showed that maximum strength in each station was increased after BFR resistance exercise and TRT (P<0.05). Thigh muscle CSA also was increased after BFR resistance exercise and TRT; however the increase in thigh muscle CSA was higher in resistance exercise with BFR than TRT. For GH no significant differences were observed after the BFR resistance exercise and TRT methods.
Conclusions: The data suggest that BFR resistance exercise method is a superior method for thigh muscle CSA in compare to the TRT method.