Time course of changes in V?<scp>o</scp>_2peak and O₂ extraction during ramp cycle exercise following HIIT versus moderate-intensity continuous training in type 2 diabetes

In the present study, we assessed time course of adaptations in peak oxygen uptake (V?o 2peak ) and muscle fractional (O 2 extraction (using near-infrared spectroscopy) following 12 wk low-volume high-intensity interval training (HIIT) versus moderate-intensity continuous endurance (MICT) adults with uncomplicated type diabetes (T2D). Participants T2D were randomly assigned to MICT ( n = 12, 50 min cycling) or HIIT 9, 10 × 1 at ?90% maximal heart rate) a nonexercising control group 9). Exercising groups trained three times per week measurements taken every 3 wk. The rate deoxygenation (i.e., deoxygenated hemoglobin myoglobin concentration, ?[HHb + Mb]) profiles vastus lateralis normalized 100% response, plotted against % power output (PO), fitted double linear regression model. V?o increased P &lt; 0.05) by (+17%) (+8%), no further significant changes thereafter. Total increases posttraining 27% 14%, respectively. %?[HHb Mb] %PO slope first segment was reduced beyond MICT, No observed group. Low-volume induced improvements similar course, these likely, least part, due an improved microvascular O delivery.