Assessment of body composition in junior representative and first grade rugby league players using dual x-ray absorptiometry

• Published in: Science and medicine in football Vol. 1; no. 3; pp. 197 - 202
• Main Authors: Greene, David A., Varley, Benjamin, Duncan, Craig S., Gabbett, Tim J.
• Format: Journal Article
• Language: English
• Published: Routledge 02.09.2017
• Subjects: body composition; DXA; Rugby League
• ISSN: 2473-3938; 2473-4446
• DOI: 10.1080/24733938.2017.1331043

Objectives: Body composition is important to rugby league coaches because, in concert with other factors such as muscle and tendon properties and neurophysiology, composition values provide a general indication of strength and power and an ability to absorb high impacts. We compared whole-body and regional body composition values of junior representative (under 16 years, 18 years) and senior professional (1st grade) National Rugby league (NRL) players using Dual X-ray Absorptiometry (DXA). Methods: One hundred and forty-two junior representative and senior 1st grade rugby league players completed a whole-body DXA scan. Juniors comprised U/16 (mean age 15.9 ± 0.8 years, n = 25), and U/18 (17.9 ± 0.6 years, n = 21) state-level representative players while 1st grade players (25.3 ± 2.3 years, n = 96) were drawn from three NRL clubs. Results: Junior representative players were lighter in body mass and shorter in stature compared to 1st grade players. Despite greater lean tissue mass (LTM) in 1st grade players, there were no between-group differences in fat mass (FM) at whole-body or regional sites. Conclusions: When comparing body composition values between junior representative players to 1st grade players' results show that senior players have greater LTM but do not differ in FM relative to junior players. Findings suggest that junior training programs should emphasise developmentally-appropriate resistance training with a continuation of current practices to maintain FM.