Validity of Heart Rate-Based Models for Estimating Oxygen Uptake During Tennis Play

Baiget, E, Iglesias, X, and Rodriguez, FA. Validity of heart rate-based models for estimating oxygen uptake during tennis play. J Strength Cond Res 34(11): 3208-3216, 2020-This study aimed to assess the validity of an on-court tennis test (specific endurance tennis test [SET-Test]) and 2 heart rate (HR)-based methods for estimating oxygen uptake (V?o(2)) in competitive tennis players. Thirty-five male players performed a SET-Test to relate test duration (minutes) and V?o(2). Two weeks later, 16 players performed a simulated match play set where HR and V?o(2) (V?o(2-PLAY), criterion value) were measured and then compared with V?o(2) values predicted from the HR/V?o(2) linear regression equations derived from the SET-Test (pV?o(2-TEST)) and from the one set match play (pV?o(2-PLAY)). Test duration and V?o(2-TEST) were strongly correlated (r(2) = 0.821, p < 0.001, SEE = 5.6 ml center dot kg(-1)center dot min(-1)), indicating that SET-Test outcome is a somewhat good indicator of aerobic fitness in tennis players, likely to be useful for training purposes. pV?o(2-PLAY) and V?o(2-PLAY) (criterion value) were strongly correlated (r(2) = 0.832, p < 0.001) and SEE was moderate (3.5 ml center dot kg(-1)center dot min(-1) = 11.5%). pV?o(2-TEST) differed from the criterion (32.4 +/- 10.7 vs. 30.8 +/- 8.6 ml center dot kg(-1)center dot min(-1), p < 0.001) and, although strongly correlated (r(2) = 0.689, p < 0.001), an overestimation occurred (mean Delta = 1.6 ml center dot kg(-1)center dot min(-1) = 4.9%), yielding a high SEE (4.8 ml center dot kg(-1)center dot min(-1) = 15.6%). We conclude that (a) SET-Test performance is a valid and moderately accurate predictor of V?o(2); and (b) the individual HR-V?o(2) regression equation generated during tennis match play predicts V?o(2) with greater accuracy than the regression derived from the SET-Test.