The energetics of middle-distance running

Abstract

In order to assess the relative contribution of aerobic processes to running velocity (v), 27 male athletes were selected on the basis of their middle-distance performances over 800, 1500, 3000 or 5000 m, during the 1987 track season. To be selected for study, the average running velocity\((\bar \upsilon )\) corresponding to their performances had to be superior to 90% of the best French\(\bar \upsilon \) of the season. Maximum O₂ consumption\((\dot V_{O_{2{\text{ max}}} } )\) and energy cost of running (C) had been measured within the 2 months preceding the track season, which, together with oxygen consumption at rest\((\dot V_{O_{2{\text{ rest}}} } )\) allowed us to calculate the maximalv that could be sustained under aerobic conditions:\(\upsilon _{a max} {\text{ = }}(\dot V_{O_{2{\text{ max}}} } - \dot V_{O_{2{\text{ rest}}} } ) \times {\text{ C}}^{{\text{ - 1}}} \). The treadmill runningv corresponding to a blood lactate of 4 mmol·⁻¹ (v_la4), was also calculated. In the whole group, C was significantly related to height (r=−0.43;P<0.03). Neither C nor\(\dot V_{o_{2{\text{ }}max} } \) (with, in this case, the exception of the 3000 m athletes) were correlated to\(\bar \upsilon \). On the other hand,v_{a max} was significantly correlated to\(\bar \upsilon \) over distances longer than 800 m. These\(\bar \upsilon \) were also correlated tov_la4. Howeverv_la4 occurred at 87.5% SD 3.3% ofv_{a max}, this relationship was interpreted as being an expression of the correlation betweenv_{a max} and\(\bar \upsilon \). Calculation ofv_{a max} provided a useful means of analysing the performances. At the level of achievement studied,\(\bar \upsilon \) sustained over 3000 m corresponded tov_{a max}. The shape of the relationship ofv/v_{a max} as a function of the duration of the event raised the question of a possible change in C as a function of v during middle-distance running competitions.