Applied high-intensity interval cardio yoga improves cardiometabolic fitness, energetic contributions, and metabolic flexibility in healthy adults

Purpose: Currently, there is no interventional approach to increase the intensity of Surya Namaskar a popular hatha yoga sequence used worldwide. Therefore, this study investigated how tempo-based high-intensity interval cardio yoga (HIICY) and traditional interval hatha yoga (TIHY) affects cardiometabolic fitness in active adults. Methods: Twenty physically active male and female individuals were randomly separated into HIICY (5 males, 5 females, 1.5 s tempo) and TIHY (5 males, 5 females, 3 s tempo) groups. The intervention included twelve exercise sessions for 4 weeks in both groups. Participants conducted a ramp test to determine their maximal oxygen uptake ( [Formula: see text] O(2max)), maximal velocity at [Formula: see text] O(2max) (v [Formula: see text] O(2max)), and maximal heart rate (HR(max)). Afterward, they performed a 10-min high-intensity cardio yoga test (HICYT) to determine heart rate (HR(peak) and HR(mean)), oxygen uptake ( [Formula: see text] O(2peak) and [Formula: see text] O(2mean)), respiratory exchange ratio (RER), blood lactate concentrations (La(−) (peak) and ∆La(−)), fat and carbohydrate oxidations (FATox, CHOox), and energetic contributions (oxidative; W (Oxi), glycolytic; W (Gly), and phosphagen; W (PCr), total energy demand; W (Total)). Results: [Formula: see text] O(2max) and v [Formula: see text] O(2max) showed time and group × time interactions (p < 0.01, p < 0.0001, p < 0.001, respectively). [Formula: see text] O(2max) after HIICY was significantly higher than in pre-testing and following TIHY (p < 0.001, p < 0.0001, respectively). [Formula: see text] O(2peak), [Formula: see text] O(2mean), RER, HR(peak), and HR(mean) during the 10-min HICYT showed significant time effects (p < 0.05). ∆La(−) indicated a group × time interaction (p < 0.05). Group x time interaction effects for FATox at the fourth and sixth minute were observed (p < 0.05, respectively). Absolute (kJ) and relative (%) W (Oxi), W (Gly), and W (Total) showed time and group × time interaction effects (p < 0.05, p < 0.01, respectively). Furthermore, %W (Gly) was reduced following HIICY (p < 0.05). Additionally, [Formula: see text] O(2max) and v [Formula: see text] O(2max) were highly correlated with W (Oxi) in kJ (r = 0.91, 0.80, respectively). Moderate to high correlations were observed among CHOox, FATox, and absolute [Formula: see text] O(2max) (r = 0.76, 0.62, respectively). Conclusion: A 4-week period of HIICY improved cardiometabolic fitness, oxidative capacity, and metabolic flexibility compared with TIHY, in physically active adults. Therefore, HIICY is suitable as HY-specific HIIT and time-efficient approach for relatively healthy individuals.