Abstract
Purpose
This study examined sex differences in cardiometabolic and perceptual responses to high-intensity functional training (HIFT) and kettlebell complexes (KC).Methods
Seventeen men (age = 26.9 ± 9.5 year) and 18 women (age = 22.2 ± 2.8 year) completed HIFT and KC protocols. Oxygen consumption (VO2), heart rate (HR), ventilation (VE), respiratory exchange ratio (RER), blood lactate concentration (BLa), rating of perceived exertion (RPE), and the Feeling Scale (FS) were measured during exercise.Results
Women demonstrated significantly higher (p ≤ 0.001) mean HR (156 ± 14 vs. 134 ± 17 b·min⁻¹), %HRmax (84 ± 8 vs. 76 ± 8), %VEmax (62 ± 16 vs. 52 ± 12), peak HR (183 ± 8 vs. 167 ± 15 b·min⁻¹), and higher RER (1.11 ± 0.08 vs. 1.05 ± 0.10) versus men. Relative VO2 (%VO2max: 62 ± 8 vs. 59 ± 10) did not differ between sexes (p = 0.285), despite men exhibiting higher absolute VO2 (1.87 ± 0.40 vs. 1.37 ± 0.26 L·min⁻¹; p 2 (%VO2max: 63 ± 8 vs. 58 ± 10), peak VO2 (%VO2peak: 81 ± 12 vs. 73 ± 11), VE (%VEmax: 61 ± 15 vs. 54 ± 14), and RER (1.11 ± 0.10 vs. 1.05 ± 0.09) versus KC.Conclusion
Women exhibited greater relative internal load during exercise despite similar relative VO2, suggesting a greater cardiovascular stimulus during whole-body interval training.