Metabolic Energy Contributions During High-Intensity Hatha Yoga and Physiological Comparisons Between Active and Passive (Savasana) Recovery

Purpose: The objective of this study was to investigate metabolic energy contributions during high-intensity hatha yoga (HIHY) and to compare changes in physiological variables between active and passive recovery methods. Methods: The study involved 20 women yoga instructors (n = 20) who performed 10 min of HIHY (vigorous sun salutation). Upon completion, they were randomly assigned to either active (walking; n = 10) or passive (savasana; n = 10) recovery groups for a period of 10 min. During HIHY, physiological variables such as heart rate (HR_peak and HR_mean), oxygen uptake (VO_2peak and VO_2mean), and blood lactate concentrations (peak La^-) were measured. Energetic contributions (phosphagen; W_PCR, glycolytic; W_Gly, and oxidative; W_Oxi) in kJ and % were estimated using VO₂ and La^- data. Furthermore, the metabolic equivalents (METs) of VO_2peak and VO_2mean were calculated. To compare different recovery modes, HR_post, ΔHR, VO_2post, ΔVO₂, recovery La^-, and recovery ΔLa^- were analyzed. Results: The results revealed that HR_peak, VO_2peak, and peak La^- during HIHY showed no differences between the two groups (p > 0.05). Values of HR_peak, HR_mean, METs of VO_2peak and VO_2mean, and La^- during HIHY were 95.6% of HR_max, 88.7% of HR_max, 10.54 ± 1.18, 8.67 ±.98 METs, and 8.31 ± 2.18 mmol·L^-1, respectively. Furthermore, W_Oxi was significantly higher compared with W_PCR, W_Gly, and anaerobic contribution (W_PCR + W_Gly), in kJ and % (p < 0.0001). VO_2post and recovery ΔLa^- were significantly higher in the active recovery group (p < 0.0001, p = 0.0369, respectively). Values of ΔVO₂ and recovery La^- were significantly lower in the active group compared with the passive group (p = 0.0115, p = 0.0291, respectively). Conclusions: The study concluded that high-intensity hatha yoga which was performed for 10 min is a suitable option for relatively healthy people in the modern workplace who may have hatha yoga experience but do not have time to perform a prolonged exercise. Following active recovery, they can participate in further HIHY sessions during short breaks. Furthermore, a faster return to work can be supported by physiological recovery.