ORIGINAL ARTICLES  PHYSIOLOGY AND BIOMECHANICS 

The Journal of Sports Medicine and Physical Fitness 2013 February;53(1):34-41

Copyright © 2013 EDIZIONI MINERVA MEDICA

lingua: Inglese

The effects of a resistance-training program on strength, body composition and baseline hormones in male athletes training concurrently for rugby union 7’s

Crewther B. T. ^{1, 2}, Heke T. L. ³, Keogh J. W. ^{3, 4} ✉

¹ Hamlyn Centre, Imperial College, London, UK; ² Health and Sport Portfolio, College of Engineering, Swansea University, Swansea, UK; ³ Sports Performance Research Institute New Zealand, School of Sport and Recreation, Auckland University of Technology, Auckland, New Zealand; ⁴ Bond University Research Centre for Health, Exercise and Sports Sciences, Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Australia; ⁵ Faculty of Sciences, Health, Education, Engineering, University of the Sunshine Coast, Queensland, Australia

Aim: To examine the effects of a resistance-training program on strength, body composition and baseline hormones in male athletes training concurrently for rugby union 7’s.
Methods: Participants (N.=12) completed a six-week resistance-training program focusing on general strength development while still performing additional rugby union 7’s training involving agility, speed and cardiovascular fitness. One repetition maximum (1RM) strength was assessed pre and post training across 5 exercises (bench press, back squats, deadlifts, military press and chins), along with body composition and baseline salivary testosterone (T) and cortisol (C) concentrations.
Results: Significant improvements in bench press (11%), back squat (13%), deadlift (13%), military press (10%) and chin-up (6%) 1RM strength were observed after training (P < 0.05). These changes were accompanied by a significant reduction (-1%) in body fat and an increase (1.3%) in fat-free mass. Baseline T and C concentrations and the T/C ratio did not change significantly with training (P>0.05). Correlational analyses indicated that most of the individual changes in strength, body composition and hormones were not significantly related.
Conclusion: The implementation of a resistance-training program in male athletes already training for rugby union 7’s led to all-round improvements in maximal dynamic strength even while they continued to perform other forms of rugby-specific training. These findings support the use of resistance exercise as a supplement to sport-specific training for improving the performance capacity of 7’s rugby players.