Background and Aim: It seems that performing exercise at different times of the day is associated with different responses in the functioning of the cardiac autonomic system. The aim of the present study was to investigate the acute effects of exhaustive exercise and circadian rhythms on recovery period heart rate variability in sedentary men with prehypertension.
Methods: A total of 15 sedentary men with prehypertension performed exhausting aerobic exercise in three sessions in the morning, noon, and afternoon using intra-subject comparisons and crossover design. Heart rate variability at baseline, end of exercise, and 5, 10, 20, and 30 minutes of recovery period were recorded at each time of exercise using a heart rate Holter-monitor. Preliminary data were analyzed using repeated measures analysis of variance and bonferroni post hoc test.
Results: Considering the participants' descriptive data (mean±SD age; 35.3±3.87, weight; 89.2±5.73, and mean blood pressure; 101.2±4.68), the results showed that performing exhausting exercise in the afternoon time compared to the morning and noon time caused a significant difference in standard deviation of RR interval (p=0/01 morning 10 min, p=0/01 noon 10 min), variance of RR interval (p=0/01 morning 5 min, p=0/001 noon 5 min; p=0/03 morning 10 min, p=0/001 noon 10 min) time indices and low-frequency(p=0/03 morning 5 min, p=0/01 noon 5 min; p=0/01 morning 10 min), and high-frequency(p=0/01 morning 5 min, p=0/01 noon 5 min; p=0/04 morning 10 min, p=0/01 noon 10 min) indices of heart rate variability in 5 and 10 min of recovery period.
Conclusion: It was found that performing exhaustive exercise by sedentary males with hypertension in the afternoon is desirable.
Type of Study:
Original |
Subject:
Physical Education and Sports Science ( Sport physiology- Sport biomecanic Received: 2021/02/18 | Accepted: 2022/05/15 | Published: 2023/01/2
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