open access

https://doi.org/10.14943/b.edu.120.45

https://hdl.handle.net/2115/56424

Relationship Between Heart Rate Drift and Autonomic Nerve Activity During Prolonged Constant-load Exercise

日本語

Parasympathetic nerve activity

2014-06-30

北海道大学大学院教育学研究院

北海道大学大学院教育学研究院紀要

120

45-52

The aim of this study was to determine the relationship between heart rate (HR) drift and cardiac autonomic nerve activity during constant-load prolonged exercise. Seven healthy men performed a moderate-intensity (about 60% of peak oxygen uptake) 60-min cycling exercise. Autonomic nerve activity was evaluated by the frequency analysis of HR variability. The powers of high frequency (HF, 0.15-0.4 Hz), low frequency (LF, 0.04-0.15 Hz) and LF to HF ratio (LF/HF) components of HR Variability (HRV) have been shown to estimate cardiac vagal and sympathetic activities. The results showed that HR was rapidly increased from (67 ± 8 bpm) to (131 ± 14 bpm) at the 3rd minute after start from the state of rest (Fig. 2, P<0.05), thereafter, at the first half of the exercise (the 30th minute：146±17 bpm) and the end of the exercise (the 60th minute： 156±13 bpm), where HR was both increased significantly (Fig. 2, P<0.05) . Although the LF/HF showed the tendency (0.05<P=0.087<0.1) to increase from the state of rest (2.90±1.96) to the 3rd minute of exercise (9.35±6.54), after that, it did not show any change at the 30th (9.94±5.24) minute and the end of the exercise (4.99±4.50) (Fig. 2) . The HF was rapidly decreased after 3-minute exercise from the state of rest； at rest： 521.28 ± 307.11 (beats/min) 2/Hz； the 3rd minute： 56.57 ± 45.63 (beats/min) 2/Hz, P<0.05) . Although it showed significantly decreased from 3rd minute to the 30th minute of exercise (0.88±1.12 (beats/min) 2/Hz (P<0.05), HF did not show statistically significant change from the 30th minute to the end of the exercise (0.51 ±0.55 (beats/min) 2/Hz, 0.05<P=0.094<0.1) . The HR drift in the first half of the exercise (3-30 min) was considered not to be related to sympathetic activity, but related to parasympathetic nerve activity. In the last half exercise (30-60 min), the HR drift seemed to be independent of the autonomic nervous activity.

紀要論文

Version of Record

1882-1669

AA12219452