Cardiovascular Fitness and Maximal Heart Rate Differences among Three Ethnic Groups

The current study examines maximal heart rate and maximal treadmill time differences among three ethnic groups. In 1985, 1,047 city employees (572 male, 475 female) participated in a comprehensive health promotion program. Data were collected from a self-administered health and lifestyle questionnaire, maximal treadmill exercise stress test, and other clinical measures. The participants were divided into white male (n = 368), black male (n = 159), Mexican-American male (n = 45), white female (n = 256), black female (n = 189), and Mexican-American female (n = 30) subgroups based on self-reported ethnic identity. Univariate analyses revealed no significant differences in age-adjusted maximal heart rate or maximal treadmill time for males. Mean age-adjusted treadmill time for black females (478.0 ± 228.2 s) was significantly lower than for white (652.5 ± 227.7 s) and Mexican-American (594.5 ± 226.7 s) females (p <. 05). Mean age-adjusted maximal heart rate for black females (174.4 ± 12.4 beats/min) was significantly lower than for white (179.3 ± 13.4 beats/min) and Mexican-American (182.0 ± 13.5 beats/min) females (p < .05). Following adjustment for cardiovascular fitness level, that is, treadmill time, as well as age, these differences were no longer apparent. We concluded that the comparatively low maximal heart rate of black females may be partially explained by a significantly lower cardiovascular fitness level relative to white and Mexican-American females.