Determining V̇O_2max in competitive swimmers: Comparing the validity and reliability of cycling, arm cranking, ergometer swimming, and tethered swimming

Objectives: This study aims to identify the optimal method for determining V̇O_2max 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 V̇O_2max. Validity was assessed in terms of the amount of variance of the performance on a 1500-m time trial explained by the estimated V̇O_2max . Test–retest reliability was evaluated using the intraclass correlation coefficient (ICC). Results: V̇O_2max obtained from tethered swimming, ergometer swimming, and cycling explained a similar amount of variance of the 1500-m performance (R² = 0.64, 0.64 and 0.65, respectively). However, ergometer swimming yielded significantly lower V̇O_2max 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 V̇O_2max (43.14 ± 7.81 ml/kg/min). Tethered swimming showed good reliability (ICC = 0.81). Conclusions: Bicycle and tethered swimming tests demonstrated high validity with comparable V̇O_2max 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.