Abstract
Changes in body components occur over a season, but their impact on performance is
still unclear. We aimed to analyze the relationship between changes in leg strength
and jump performance with body composition over a season in highly trained athletes.
Measures from the beginning to the main competitive periods of a season were obtained
in 40 male and 23 female basketball, handball and volleyball players (20±5 years)
for fat (FM) and fat-free mass (FFM) estimated by DXA. Total body water (TBW) and
extracellular water (ECW) were assessed by deuterium and bromide dilution, respectively,
and intracellular water (ICW) was calculated as TBW minus ECW. Maximal strength was
determined by the leg press, while jumping height was assessed with squat (SJ) and
countermovement (CMJ) jumps. Significant improvements in strength (12.5±20.8%) and
jumping height (SJ:8.3±13.9%; CMJ:6.3±8.5%) were found. FFM, TBW and ECW significantly
increased (3.0±2.7%; 1.7±5.5%; 3.0±8.6%, respectively), while %FM decreased (−4.5±9.1%)
and no changes were observed in ICW (1.2±9.7%). Among body composition changes only
ICW was associated with performance even adjusted for gender, age, season length and
sport (strength: β=71.209, p=0.012; SJ: β=0.311, p=0.049; CMJ: β=0.366, p=0.018).
Body composition, strength and jumping height improved over a season and ICW was the
main predictor of performance in national level players.
Key words
dilution techniques - body composition - athletic training - water compartments -
dual energy x-ray absorptiometry
