Figure 3. Adaptive responses of maximal oxygen uptake (V̇O_2max), cardiac output (Q̇_max), and stroke volume (SV_max) to high-intensity interval training using anaerobic speed reserve (HIIT_ASR), HIIT using finial velocity during 30-15_IFT test (HIITv_IFT), and HIIT using maximal aerobic speed (HIIT_MAS). Triangles indicate individual percent change from baseline (X-axes) and horizontal bars represent mean group response. †  Denotes significantly different versus pre-training (p ≤ 0.05).