Cerebral oxygenation during cortical activation: the differential influence of three exercise training modalities. A randomized controlled trial.

Abstract

To determine if a cerebral oxygenation response during cortical activation is influenced by exercise training mode. Sixty-seven individuals (55-75years old) volunteered for this 16-week intervention study. Participants were randomized into a resistance training (RT) group (n=22), high-intensity interval training (HIIT) group (n=13), moderate continuous training (MCT) group (n=13) and a control (CON) group (n=19). Near-infrared spectroscopy was used to measure cerebral oxygenation during the Stroop task. A submaximal Bruce treadmill test was used to measure changes in walking endurance. The GROUP×TIME interaction for reaction time on the naming and executive Stroop conditions were not significant (P>0.05). At post-test, the CON group showed increased brain activation, with significantly higher relative oxy-haemoglobin (O2Hb) values during the naming Stroop condition compared to pre-test (P=0.03), while their increased relative O2Hb on the complex condition showed a distinct trend toward significance (P=0.09). MCT and HIIT participants exhibited decreased brain activation during the Stroop task, with MCT showing a significant increase in relative deoxy-haemoglobin (HHb) compared to pre-test during the naming and executive Stroop conditions (P<0.05). The HIIT group improved significantly in walking endurance (P=0.04). Sixteen weeks of exercise training resulted in more efficient cerebral oxygenation during cortical activation compared to a no-exercise control group. Furthermore, HIIT and MCT were superior to RT for task-efficient cerebral oxygenation and improved oxygen utilization during cortical activation in older individuals.