Cross-validation of age-predicted maximal heart rate equations among female collegiate athletes

The purpose of this study was to determine the accuracy of 3 general and 2 female-specific age-predicted maximal heart rate (HR max) prediction equations in female collegiate athletes. Thirty female collegiate athletes (age 21.5 ± 1.9 years, height 164.7 ± 6.6 cm, weight 61.3 ± 8.2 kg) participated. HR max was determined with a maximal graded exercise test and predicted with 3 general equations (Fox et al., Astrand, and Tanaka et al.) and 2 female-specific equations (Fairbarn et al. and Gulati et al.). There was no significant difference between observed HR max (185.9 ± 5.0 b·min -1) and the Fairbarn (187.5 ± 1.2 b·min -1) and Gulati (187.1 ± 1.7 b·min -1) equations (p 0.11 and 0.23, respectively). The Fox (198.5 ± 1.9 b·min -1), Astrand (198.1 ± 1.6 b·min -1), and Tanaka (193.0 ± 1.4 b·min -1) equations provided significantly higher estimates compared with observed HR max (p < 0.001 for each). The standard error of the estimate was similar for all the prediction equations (between 5.0 and 5.4 b·min -1), but the total error was smallest for Fairbarn and Gulati (5.3 b·min -1 for each) and largest for Fox and Astrand (13.9 and 13.3 b·min -1, respectively). The 95% limits of agreement of the mean error were similar for all of the prediction equations, with values varying between 9.9 and 10.5 b·min -1. Because of the wide limits of agreement displayed by each equation, the use of age-predicted methods for estimating HR max in collegiate female athletes should be performed only with caution.