Measured maximal heart rates compared to commonly used age-based prediction equations in the heritage family study

Objective: The purpose of this study was to examine how well two commonly used age-based prediction equations for maximal heart rate (HR_max) estimate the actual HR_max measured in Black and White adults from the HERITAGE Family Study. Methods: A total of 762 sedentary subjects (39% Black, 57% Females) from HERITAGE were included. HR_max was measured during maximal exercise tests using cycle ergometers. Age-based HR_max was predicted using the Fox (220-age) and Tanaka (208 - 0.7 × age) formulas. Results: The standard error of estimate (SEE) of predicted HR_max was 12.4 and 11.4 bpm for the Fox and Tanaka formulas, respectively, indicating a wide-spread of measured-HR_max values are compared to their age-predicted values. The SEE (shown as Fox/Tanaka) was higher in Blacks (14.4/13.1 bpm) and Males (12.6/11.7 bpm) compared to Whites (11.0/10.2 bpm) and Females (12.3/11.2 bpm) for both formulas. The SEE was higher in subjects above the BMI median (12.8/11.9 bpm) and below the fitness median (13.4/12.4 bpm) when compared to those below the BMI median (12.2/11.0 bpm) and above the fitness median (11.4/10.3) for both formulas. Conclusion: Our findings show that based on the SEE, the prevailing age-based estimated HR_max equations do not precisely predict an individual's measured-HR_max.