Determining V̇O2max in competitive swimmers: comparing the validity and 1 reliability, of cycling, arm cranking, ergometer swimming, and tethered swimming

Objective This study aims to identify the optimal method for determining V̇O2max in competitive swimmers in terms of validity and test–retest reliability. Design Controlled experiment. Methods Twenty competitive swimmers performed four maximal incremental exercise tests: cycling, arm cranking, ergometer swimming, and tethered swimming. Gas analysis was conducted to estimate V̇O2max. Validity was assessed in terms of the amount of variance explained by the estimated V̇O2max of the performance on a 1500-m time trial. Test–retest reliability was evaluated using the intraclass correlation coefficient (ICC). Results V̇O2max obtained from tethered swimming, ergometer swimming, and cycling explained a similar amount of variance of the 1500-m performance (R2 = 0.64, 0.64, 0.65, respectively). However, ergometer swimming yielded significantly lower V̇O2max estimates (40.54 ± 6.55 ml/kg/min) than tethered swimming (54.40 ± 6.21 ml/kg/min) and cycling (54.39 ± 5.63 ml/kg/min). Arm cranking resulted in both a lower explained variance (R2 = 0.41) and a significantly lower V̇O2max (43.14 ± 7.81 ml/kg/min). Tethered swimming showed a good reliability (ICC = 0.81). Conclusions Bicycle and tethered swimming tests demonstrated high validity with comparable V̇O2max estimates, explaining a large proportion of differences in endurance performance. Choosing between these two methods involves a trade-off between a higher practical applicability and reliability of the bicycle test and the more sport-specific nature of the tethered swimming test.