5 km front crawl in pool and open water swimming: breath-by-breath energy expenditure and kinematic analysis.

Breath-by-breath energy expenditure during open water swimming has not yet been explored in an ecological environment. This study aimed to investigate and compare energetics and kinematics of 5 km swimming, in both swimming pool and open water conditions. Through four independent studies, oxygen uptake ([Formula: see text] In the swimming pool, swimmers started with an above average swimming speed (v), losing efficiency along the 5 km, despite apparent homeostasis for [La Small fluctuations were observed for energetic variables in both conditions, but changes in C were lower in swimming pool than in open water. Coaches should adjust the training plan accordingly to the specificity of open water swimming.