Comparison of heart rate measured by Polar RS 400 and ECG, validity and repeatability .
Aims: The purpose of this study was to investigate criterion-related validity and test–retest repeatability of the heart rate monitor Polar RS400 versus electrocardiogram (ECG). Methodology: Ten healthy subjects, 19–34 years, performed a cycle ergometer test 5 min on each load (50, 100 and 150 W). Heart rate (HR) was measured with ECG and Polar RS400 and recorded digitally. After at least one hour