Metabolic power and energy expenditure in an international men's hockey tournament.

The purpose of this study was to ascertain the typical metabolic power characteristics of elite men's hockey, and whether changes occur within matches and throughout an international tournament. National team players (n = 16), divided into 3 positional groups (strikers, midfielders, defenders), wore Global Positioning System devices in 6 matches. Energetic (metabolic power, energy expenditure) and displacement (distance, speed, acceleration) variables were determined, and intensity was classified utilising speed, acceleration and metabolic power thresholds. Midfielder's average metabolic power (11.8 ± 1.0 W · kg-1) was similar to strikers (11.1 ± 1.3 W · kg-1) and higher than defenders (10.8 ± 1.2 W · kg-1, P = 0.001). Strikers (29.71 ± 3.39 kJ · kg-1) expended less energy than midfielders (32.18 ± 2.67 kJ · kg-1, P = 0.014) and defenders (33.23 ± 3.96 kJ · kg-1, P < 0.001). Energetic variables did not change between halves or across matches. Across all positions, over 45% of energy expenditure was at high intensity (>20 W · kg-1). International hockey matches are intense and highly intermittent; however, intensity is maintained throughout matches and over a tournament. In isolation, displacement measures underestimate the amount of high-intensity activity, whereas the integration of instantaneous speed and acceleration provides a more comprehensive assessment of the demands for variable-speed activity typically occurring in hockey matches.