The effects of different interval exercise protocols on blood pressure and autonomic nervous system in Hypertensive Patients
Poster Presentation
Paper ID : 1771-SSRC
Authors
1Department of Biological Sciences in Sport, Faculty of Sport Sciences and Health, Shahid Beheshti University, Tehran, Iran
2Department of Kinesiology, University of Connecticut, Storrs, CT 06269, USA
Abstract
Objective: This study aimed to assess the impact of different interval exercise protocols on blood pressure and heart rate variability (HRV) in individuals with elevated blood pressure.
Methods: Twelve (7 women, 5 men) sedentary individuals (Mean±SD; BP, 129±3.5 mmHg; age, 50±7 yrs; BMI, 28.8±4 kg/m2) participated in three different interval protocols. The exercise protocols included moderate-intensity interval exercise (MIIE, 4 repetitions of 4min activity at 70% of VO2peak interspersed by 3min of recovery), high-intensity interval exercise (HIIE, 10 repetitions of 1min activity at 90% of VO2peak interspersed by 1min of recovery), and sprint interval exercise (SIE, 8 repetitions of 15s activity at 120% of VO2peak interspersed by 1min of recovery). Blood pressure and HRV variables including low frequency (LF), high frequency (HF), ratio of low Frequency to high Frequency (LF/HF), the standard deviation of NN intervals (SDNN), and the proportion of NN50 divided by the total number of NN intervals (PNN50) were measured before, immediately after, and at 5, 10, 15, 30, 45, and 60min post-exercise.
Results: Statistical analysis revealed a significant increase in systolic and diastolic blood pressure, HR, and LF/HF ratio (P<0.05) following all interval exercise protocols. Simultaneously, there were significant decreases in LF, HF, PNN50, and SDNN (P<0.05). However, there were no significant differences in systolic and diastolic blood pressure, LF/HF, and HF among the three protocols (P>0.05). When HRV variables and HR were compared among the three trials, HR, LF, PNN50, and SDNN exhibited significant differences (P<0.05). Post-hoc analyses revealed that changes following SIE were lower compared to MIIE and HIIE for SDNN, PNN50, and LF.
Conclusion: It is concluded that interval exercise induces temporary changes in hemodynamic and HRV variables in middle-aged individuals with elevated blood pressure, though, the responses to interval exercise is related to the intensity, SIE with higher intensity and lower work-to-rest ratio induced least changes and is safer than the MIIE and HIIE.
Methods: Twelve (7 women, 5 men) sedentary individuals (Mean±SD; BP, 129±3.5 mmHg; age, 50±7 yrs; BMI, 28.8±4 kg/m2) participated in three different interval protocols. The exercise protocols included moderate-intensity interval exercise (MIIE, 4 repetitions of 4min activity at 70% of VO2peak interspersed by 3min of recovery), high-intensity interval exercise (HIIE, 10 repetitions of 1min activity at 90% of VO2peak interspersed by 1min of recovery), and sprint interval exercise (SIE, 8 repetitions of 15s activity at 120% of VO2peak interspersed by 1min of recovery). Blood pressure and HRV variables including low frequency (LF), high frequency (HF), ratio of low Frequency to high Frequency (LF/HF), the standard deviation of NN intervals (SDNN), and the proportion of NN50 divided by the total number of NN intervals (PNN50) were measured before, immediately after, and at 5, 10, 15, 30, 45, and 60min post-exercise.
Results: Statistical analysis revealed a significant increase in systolic and diastolic blood pressure, HR, and LF/HF ratio (P<0.05) following all interval exercise protocols. Simultaneously, there were significant decreases in LF, HF, PNN50, and SDNN (P<0.05). However, there were no significant differences in systolic and diastolic blood pressure, LF/HF, and HF among the three protocols (P>0.05). When HRV variables and HR were compared among the three trials, HR, LF, PNN50, and SDNN exhibited significant differences (P<0.05). Post-hoc analyses revealed that changes following SIE were lower compared to MIIE and HIIE for SDNN, PNN50, and LF.
Conclusion: It is concluded that interval exercise induces temporary changes in hemodynamic and HRV variables in middle-aged individuals with elevated blood pressure, though, the responses to interval exercise is related to the intensity, SIE with higher intensity and lower work-to-rest ratio induced least changes and is safer than the MIIE and HIIE.
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