Title : Effect of 2-month of yoga on cardiac autonomic stress response (hrv) during mental arithmetic task and cognitive functions among individuals with elevated anxiety: A randomized controlled trial
Abstract:
Background: Heart Rate Variability (HRV) is an independent predictor of cardiovascular morbidity and mortality. Anxiety often contribute to impairment HRV. Yoga has a positive effect of cardiac autonomic function and anxiety. However, till date no study has assessed impact of yoga on HRV during stress task among individuals with elevated anxiety.
Aim: This study examined the effects of 8-week Integrated Yoga (IY) on HRV measures during mental arithmetic task (MAT).
Methods: Sixty individuals with elevated anxiety (females:32, average age 21.07±1.73) were randomly assigned to either a yoga group (n=30) or a control group (n=30). The yoga group received 60-minute Yoga thrice in a week and the control group walked instead of yoga. ECG was recorded 20 mins (5 min Baseline, 5 min MAT, 5 min recovery, 5 min rest) at 0 week and 8 weeks. High frequency, low frequency and LF/HF were calculated using Kubios software. Sleep quality and state anxiety were also assessed.
Result: Both the groups were comparable at the baseline. At 8-weeks, significant improvement in LF, HF & LF/HF was observed during MAT in the Yoga group compared to the control group. Similaraly, sleep quality and state anxiety were also improved significantly in the yoga group compared to the control group. The control showed significant decreased in HF and increase in LF and LF/HF during MAT after 8-weeks compared to the baseline.
Conclusion: Yoga significantly improved cardiac autonomic stress response, reaction time, and sleep quality after 8 weeks, while reducing anxiety compared to a walking group. However, no notable changes in memory were observed.
