Purpose: Exercise helps improve health, and health is related to autonomic nervous function, which finds an indicator in heart rate variability. The article aims at exploring the impacts of slow jogging on sympathetic and parasympathetic functions by measuring the heart rate variability of the jogger in a real time manner, using a wearable heart rate monitor.
Methods: The measurement was conducted on a sports field at 7-9 pm. Wearing a Polar H10 chest strap heart rate monitor equipped with the Polar sensor logger 3.0.app, a 58-year-old male was asked to first walk around the sports field for 10 minutes at a pace of approximately 2 kilometers per hour and then to slowly jog for another 10 minutes at a pace of around about 4 kilometers per hour. After three days, he was instructed to start slow jogging first before switching to walking. The two exercises formed one test, and a total of six tests were conducted. The heart rate variability of the test subject during walking and slow jogging was measured and compared for analysis.
Results: After 6 careful real-time tests, data about heart rate, sympathetic function (as indicated by LF/HF ratio), parasympathetic function (RMSSD) downloaded from the aforementioned app were examined. Mean and standard deviation were calculated, and paired t test conducted. By time-domain analysis, the average number of heartbeat per minute was significantly higher during slow jogging than during walking (126.9±10.1 vs. 93.7±8.2, p= 0.001). However, no significant difference was observed in parasympathetic function between the two modes of exercise (RMSSD: 4.3±0.9 vs. 5.6±3.1, p= 0.378). By frequency-domain analysis, the sympathetic function appeared to significantly lower during slow jogging than during walking (LF/HF ratio: 4.5±4.2 vs. 17.2±1.5, p= 0.002).
Conclusion: A brief 10-minute slow jogging can significantly decrease sympathetic function, while further research is needed to study the effect of slow jogging on parasympathetic function.