Relationships between energy cost, swimming velocity and speed fluctuation in competitive swimming strokes

The purpose of the study was to analyse relationships between total energy expenditure (Etot), energy cost (EC), intra-cycle variation of the horizontal velocity of displacement of centre of mass (dv) and mean swimming velocity (v). 17 Portuguese elite swimmers (4 at Freestyle, 5 at Backstroke, 4 at Breaststroke and 4 at Butterfly) were submitted to an incremental set of nx200-m swims. Bioenergetical and biomechanical parameters presented significant interrelationships. For pooled data, the relationship between Etot and v was r=0.59 (p<0.01), between EC and dv was r=0.38 (p