Evaluating Heart Rate Variability in Rest, Free Walking and Heart-Paced Walking

Sammanfattning

Abstract Heart-paced walking has been studied to evaluate possible further health benefits to walking by looking at cardiac output. Heart-paced walking can be performed in two ways: systolic stepping, stepping at one’s heartbeat, and diastolic stepping, stepping in between one’s heartbeat. To the best of the authors’ knowledge, none of these studies have looked at the impact of heart-paced walking on a person’s heart rate variability (HRV). By calculating HRV from raw ECG data, the objective of this project was to evaluate the impact of heart-paced walking on a person’s HRV. RR-intervals were calculated as the time difference between R-peaks which were extracted with the Pan-Tompkins algorithm. The calculations were done using both the root mean square of successive differences (RMSSD) and the standard deviation of RR-intervals (SDRR). Results from calculations of HRV and heart rate (HR) for participants while resting, during free walking, and while performing systolic- and diastolic-stepping were compared using the linear mixed effects model. Average HRV calculated with the RMSSD model is 41.8 21.8 ms during rest, decreases to 24.5 18.7 ms during free walking, 23.3 19.1 ms during systolic stepping and 25.1 ms during diastolic stepping. Average HRV calculated with the SDRR model is 63.0 ms during rest, decreases to 32.5 15.9 ms during free walking, 26.0 13.6 ms during systolic stepping and 26.9 14.8 ms during diastolic stepping. The result of the project showed an effect of heart-paced walking on HRV (p<0.001 for systolic stepping and diastolic stepping), however no significant difference between systolic and diastolic stepping on HRV could be found (p>0.05) for either the SDRR model (p=0.57) or the RMSSD model (p=0.56).