A comparison of time to exhaustion at v˙O2;max in elite cyclists, kayak paddlers, swimmers and runners

A recent study has shown the reproducibility of time to exhaustion (time limit: ttime) at the lowest velocity that elicits the maximal oxygen consumption (υv˙O2 max). The same study found an inverse relationship between this time to exhaustion at υv˙O2 max and υv˙O2 max among 38 élite long-distance runners (Billat et al. 1994b). The purpose of the present study was to compare the time to exhaustion at the power output (or velocity) at v˙O2 max for different values of v˙O2 max, depending on the type of exercise and not only on the aerobic capacity. The time of exhaustion at υv˙O2 max (tlim) has been measured among 41 élite (national level) sportsmen: 9 cyclists, 9 kayak paddlers, 9 swimmers and 14 runners using specific ergometers. Velocity or power at v˙O2 max ( υv˙O2 max) was determined by continuous incremental testing. This protocol had steps of 2 min and increments of 50 W, 30 W, 0.05ms- and 2km- for cyclists, kayak paddlers, swimmers and runners, respectively. One week later, dim was determined under the same conditions. After a warm-up of 10 min at 60% of their υv˙O2 max, subjects were concluded (in less than 45 s) to their υv˙O2 max and then had to sustain it as long as possible until exhaustion. Mean values of υv˙O2 max and dim were respectively equal to 419±49 W (tlim = 222 ± 91 s), 239±56W ( tlim = 376 ± 134 s), l 46±009ms-1 ( tlim = 287± 160s) and 22.4 ±0.8kmh-1 ( tlim = 321 ±84s), for cyclists, kayak paddlers, swimmers and runners. Time to exhaustion at υv˙O2 max was only significantly different between cycling and kayaking (ANOVA test, p<0.05). Otherwise, υv˙O2max (expressed in ml min-1 kg-1) was significantly different between all sports except between cycling and running (p < 0.05). In this study, time to exhaustion at υv˙O2 max was also inversely related to υv˙O2 max for die entire group of elite sportsmen (r= -0.320, p<0.05, n = 41). The inverse relationship between υv˙O2 max and dim at υv˙O2 max has to be explained, it seems that dim depends on υv˙O2 max regardless of the type of exercise undertaken.