Main Article Content
Background and Objective: Heart rate variability (HRV) is used to assess cardiac autonomic nervous function. Oxidative stress was shown to be associated with the heart function. Phyllanthus amarus (PA) is an herbal plant which acts as an antioxidant. Thus, this study aimed to evaluate the acute treatment effects of PA on HRV after a single bout of moderate- and high-intensity exercise.
Method: Twelve men participated in two 3-day phases with a week washout in a randomized double-blinded, cross-over design. On the first day, the subjects ingested two capsules of either P.amarus (PA) (600 mg/day) or placebo (PLA) 20 min before cycling at moderate- (M) or high intensity (H). They then ingested the same kind of 4 capsules (2 capsules each meal after lunch and dinner) on the same day of the exercise and 6 capsules/day for the next 2 days.
Results: At 48h after moderate-intensity exercise, RMSSD in the PLA group was higher than in the PA group (M+PLA; 155.1+30.3 ms, M+PA; 76.1+31.7 ms;p<0.05). However, all frequency domain variables were not significant different between PLA and PA groups.
Conclusion: This study demonstrates that PA supplementation did not improve HRV induced by a single bout of moderate- and high-intensity exercise.
Keywords: antioxidant, exercise, cardiac autonomic nervous function