Impact of acute submaximal cycling exercise on skeletal muscle microvascular reactivity induced by mental arithmetic

We investigated the impact of exercise prior to mental stress on muscle microvascular function. Near-infrared spectroscopy (NIRS) was used during arterial occlusion to assess muscle oxygen consumption (mVO2), time to 50% of perfusion (T1/2), post peak-hyperemic recovery slope, and basal muscle microvascular dilation. These parameters were assessed at baseline (BL), after rest (CON) or exercise (EX), and after mental stress. mVO2 was significantly increased after EX compared to CON. T1/2 decreased regardless of condition. Basal muscle microvascular dilation increased during mental stress in CON and EX, with mental stress and EX eliciting additive effects. Post peak-hyperemic recovery slopes indicated a transient microvascular dysfunction during CON that recovered after mental stress and was absent in EX. The studys primary finding was that the combination of exercise and mental stress produced additive effects on basal microvascular muscle oxygenation, suggesting that exercise and mental stress alter microcirculatory function through separate mechanisms.