Figure 3. Individual changes (A), residuals in individual changes (B), and (C) coefficient of variations (CV) in mean group changes in maximal cardiac output (COmax) and stroke volume (SVmax) in response to seven weeks of high-intensity interval training prescribed using anaerobic speed reserve (ASRHIIT), maximal aerobic speed (MASHIIT) and maximal exertion [i.e., sprint interval training (SIT)]. Circles indicate represent the group mean response. * Significant difference vs. pre-training (p ≤ 0.05). † Significantly lower than MASHIIT group (p ≤ 0.05).