Effects of optimal pacing strategies for 400-, 800-, and 1500-m races on the V_O2 response

International audienceThe aim of this study was to compare the evolution of oxygen uptake ( _V O2) in specifically trained runners during runningtests based on the 400-, 800-, and 1500-m pacing strategies adopted by elite runners to optimize performance. Final velocitydecreased significantly for all three distances, with the slowest velocity in the last 100 m expressed relative to the peakvelocity observed in the 400 m (77%), 800 m (88%), and 1500 m (96%). Relative to the previously determined _V O2maxvalues, the respective _V O2peak corresponded to 94% (400 m) and 100% (800 and 1500 m). In the last 100 m, a decreasein _V O2 was observed in all participants for the 400-m (15.6+6.5%) and 800-m races (9.9+6.3%), whereas a nonsystematicdecrease (3.6+7.6%) was noted for the 1500 m. The amplitude of this decrease was correlated with thereduction in tidal volume recorded during the last 100 m of each distance (r¼0.85, P50.0001) and with maximal bloodlactate concentrations after the three races (r¼0.55, P50.005). The present data demonstrate that the 800 m is similar tothe 400 m in terms of decreases in velocity and _V O2