AbstractThe purpose of this study was to investigate longitudinal body mass and body
composition changes in one professional rugby union team (n=123),
(i) according to position [forwards (n=58) versus backs
(n=65)], analysis of players with 6 consecutive seasons of DXA scans
(n=21) and, (iii) to examine differences by playing status [academy
and international], over 7 years. Players [mean age: 26.8 y, body
mass index: 28.9+kg.m2] received DXA scans at fourtime
points within each year. A modest (but non-significant) increase in mean
total mass (0.8 kg) for professional players was reflected by
increased lean mass and reduced body fat mass. At all-time points, forwards
had a significantly greater total mass, lean mass and body fat percentage
compared to backs (p<0.05). Academy players demonstrated increased
total and lean mass and decreased body fat percentage over the first 3 years
of senior rugby, although this was not significant. Senior and academy
international players had greater lean mass and lower body fat percentage
(p<0.05) than non-international counterparts. Despite modest
increases in total mass; reflected by increased lean mass and reduced fat
mass, no significant changes in body mass or body composition, irrespective
of playing position were apparent over 7 years.
Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men: A secondary analysis of energy expenditure and physical activity