Submaximal heart rate testing over 5 consecutive days showed high day-to-day repeatability (ICC 0.94-0.99) with a standard error of measurement of 1.1-1.4%.
Observational (n=44)
The standard error of measurement for submaximal heart rate is 1.1-1.4%, a variation magnitude that must be accounted for when using heart rate changes to monitor training status.
A change in heart rate at a controlled submaximal exercise intensity is used as a marker of training status. However, the standard error of measurement has not been studied systematically, and therefore a change in heart rate, which can be considered relevant, has not been determined. Forty-four subjects (26.5 +/- 5.4 years; mean +/- standard deviation) participated in a submaximal running test at the same time of day for 5 consecutive days. Heart rates were determined during each of the 4 exercise intensities (2 minutes each) of increasing intensity and during the 1-minute recovery period after each stage. The repeatability of the heart rate on a day-to-day basis during the stages and recovery periods were high (intraclass correlation coefficient: 95% confidence interval R = 0.94- 0.99). The lowest variation in heart rate occurred in the fourth stage ( approximately 90% maximum heart rate) with heart rate varying 5 +/- 2 b.min(-1) (95% confidence interval for coefficient of variation = 1.1-1.4%). In conclusion, the standard error of measurement of submaximal heart rate is 1.1-1.4%. This magnitude of measurement error needs to be considered when heart rate is used as a marker of training status.
Lamberts et al. (Thu,) reported a observational. Submaximal running test was evaluated on Repeatability of heart rate on a day-to-day basis (95% CI 0.94-0.99). Submaximal heart rate testing over 5 consecutive days showed high day-to-day repeatability (ICC 0.94-0.99) with a standard error of measurement of 1.1-1.4%.