The oxygen uptake response of sprint- vs. endurance-trained runners to severe intensity running

We compared the oxygen uptake (V̇O2) response of sprint- and endurance-trained runners for an exhaustive square wave run lasting ∼2 minutes. Six sprinters and six middle- and long-distance runners each performed two exhaustive square wave runs lasting ∼2 min and two exhaustive ramp tests. V̇O2was determined breath-by-breath (QP9000; Morgan Medical, Rainham, UK) and averaged across the two repeats of each test; for the square wave test, the averaged V̇O2response (excluding the first 15s) was then modelled using a monoexponential function. Both V̇O2peak for the ramp test (67.5±3.3 vs. 54.5±8.5 ml.kg-1.min-1; P= 0.006) and the asymptotic V̇O2for the square wave run (59.6±2.7 vs. 50.7±4.6 ml.kg-1.min-1; P= 0.002) were higher for the endurance than for the sprint group. However, as a percentage of V̇O2peak, this asymptotic V̇O2did not differ between the groups (90.1±3.2% (endurance) vs. 96.2±9.0% (sprint); P= 0.145). Across all 12 subjects, the %V̇O2peak attained in the square wave run was negatively correlated with V̇O2peak (Pearson's r= -0.811, P= 0.001). We conclude that V̇O2max is more important than training history as a determinant of the %V̇O2max attained in exhaustive square wave running lasting ∼2 min.