575 Training & Testing Higham DG et al. Distribution of Fat, Non-Osseous … Int J Sports Med 2014; 35: 575–582 accepted after revision August 26, 2013 Bibliography DOI http://dx.doi.org/ 10.1055/s-0033-1355419 Published online: January 9, 2014 Int J Sports Med 2014; 35: 575–582 © Georg Thieme Verlag KG Stuttgart · New York ISSN 0172-4622 Correspondence Dean G. Higham Australian Institute of Sport Physiology PO Box 176 Belconnen 2616 Australia dean.higham@outlook.com Key words ● ▶ anthropometry ● ▶ physique ● ▶ body composition ● ▶ adiposity ● ▶ dual-energy X-ray absorptiometry Distribution of Fat, Non-Osseous Lean and Bone Mineral Mass in International Rugby Union and Rugby Sevens Players 2016. Rugby Sevens competitions are contested in a tournament format where matches are played over 7-min halves (10-min halves in tour- nament finals) with 7 players on the field for each team. The relationship between kinanthropo- metric measures and performance in Rugby Sev- ens is unclear [26]. Given the higher relative movement demands and reduced emphasis on physical contact of Rugby Sevens compared with Rugby Union [11], it is likely the body composi- tion of international-level players in each format also differ [12]. Understanding the physique characteristics of Rugby Union and Rugby Sevens players could assist in directing players into the Rugby format and positional group to which they are best physically suited. This information could also be used to increase the specificity of physical preparation and dietary programs. Although body composition is typically descri- bed at a whole-body level, dual-energy X-ray Introduction ▼ Physique traits of players are important factors associated with success in international Rugby Union. In the Rugby World Cup, the height and mass of players increased progressively between 1987 and 2007, with higher ranking teams having taller backs and heavier forwards [31]. A greater body mass is advantageous during physical con- tests for the ball. However, when additional mass is carried as fat, a player’s power-to-weight ratio, acceleration and metabolic efficiency may be compromised [35]. Higher relative fat mass is also associated with a greater reliance on carbohydrate metabolism [14] and may impair thermoregula- tion [32]. Quantifying a player’s body composition therefore provides valuable information for die- tary and training prescription. Rugby Sevens is a shortened format of Rugby Union that will debut at the Olympic Games in Authors D. G. Higham 1, 2, 3 , D. B. Pyne 1, 2 , J. M. Anson 2 , C. E. Dziedzic 4 , G. J. Slater 3, 5 Affiliations 1 Physiology, Australian Institute of Sport, Canberra, Australia 2 National Institute of Sport Studies, University of Canberra, Australia 3 Australian Rugby Union, Sydney, Australia 4 Sports Nutrition, Australian Institute of Sport, Canberra, Australia 5 School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore, Australia Abstract ▼ Differences in the body composition of interna- tional Rugby Union and Rugby Sevens players, and between players of different positions are poorly understood. The purpose of this study was to examine differences in the quantity and regional distribution of fat, non-osseous lean and bone mineral mass between playing units in Rugby Union and Rugby Sevens. Male Rugby Union (n = 21 forwards, 17 backs) and Rugby Sev- ens (n = 11 forwards, 16 backs) players from the Australian national squads were measured using dual-energy X-ray absorptiometry. The digital image of each player was partitioned into ana- tomical regions including the arms, legs, trunk, and android and gynoid regions. Compared with backs, forwards in each squad were heavier and exhibited higher absolute regional fat (Union 43–67 %; ± ~17 %, range of % differences; ± ~95 % confidence limits (CL); Sevens 20–26 %; ± ~29 %), non-osseous lean (Union 14–22 %; ± ~5.8 %; Sev- ens 6.9–8.4 %; ± ~6.6 %) and bone mineral (Union 12–26 %; ± ~7.2 %; Sevens 5.0–11 %; ± ~7.2 %) mass. When tissue mass was expressed rela- tive to regional mass, differences between Rugby Sevens forwards and backs were mostly unclear. Rugby Union forwards had higher relative fat mass (1.7–4.7 %; ± ~1.9 %, range of differences; ± ~95 % CL) and lower relative non- osseous lean mass ( − 4.2 to − 1.8 %; ± ~1.8 %) than backs in all body regions. Competing in Rugby Union or Rugby Sevens characterized the dis- tribution of fat and non-osseous lean mass to a greater extent than a player’s positional group, whereas the distribution of bone mineral mass was associated more with a player’s position. Differences in the quantity and distribution of tissues appear to be related to positional roles and specific demands of competition in Rugby Union and Rugby Sevens. Downloaded by: IP-Proxy University_Sunshine_Coast, University of the Sunshine Coast. Copyrighted material.