Exercise Modality Effect on Bioenergetical Performance at V˙O2max Intensity

AB Purpose: A bioenergetical analysis of different exercise modes near maximal oxygen consumption (V[spacing dot above]O2max) intensity is scarce, hampering the prescription of training to enhance performance. We assessed the time sustained in swimming, rowing, running, and cycling at an intensity eliciting V[spacing dot above]O2max and determined the specific oxygen uptake (V[spacing dot above]O2) kinetics and total energy expenditure (Etot-tlim). Methods: Four subgroups of 10 swimmers, 10 rowers, 10 runners, and 10 cyclists performed (i) an incremental protocol to assess the velocity (vV[spacing dot above]O2max) or power (wV[spacing dot above]O2max) associated with V[spacing dot above]O2max and (ii) a square wave transition exercise from rest to vV[spacing dot above]O2max/wV[spacing dot above]O2max to assess the time to voluntary exhaustion (Tlim-100%V[spacing dot above]O2max). The V[spacing dot above]O2 was measured using a telemetric portable gas analyzer (K4b2, Cosmed, Rome, Italy) and V[spacing dot above]O2 kinetics analyzed using a double exponential curve fit. Etot-tlim was computed as the sum of its three components: aerobic (Aer), anaerobic lactic (Analac), and anaerobic alactic (Anaalac) contributions. Results: No differences were evident in Tlim-100% V[spacing dot above]O2max between exercise modes (mean +/- SD: swimming, 187 +/- 25; rowing, 199 +/- 52; running, 245 +/- 46; and cycling, 227 +/- 48 s). In contrast, the V[spacing dot above]O2 kinetics profile exhibited a slower response in swimming (21 +/- 3 s) compared with the other three modes of exercise (rowing, 12 +/- 3; running, 10 +/- 3; and cycling, 16 +/- 4 s) (P < 0.001). Etot-tlim was similar between exercise modes even if the Analac contribution was smaller in swimming compared with the other sports (P < 0.001). Conclusion: Although there were different V[spacing dot above]O2 kinetics and ventilatory patterns, the Tlim-100%V[spacing dot above]O2max was similar between exercise modes most likely related to the common central and peripheral level of fitness in our athletes.