Abstract
This study aimed to determine the neurophysiological mechanisms underlying
the effects of aerobic exercise, which influence brain O2 consumption, on
cognitive enhancement. Sixteen healthy men were asked to complete a 2-back
test at rest and after moderate and high-intensity aerobic exercise. During
the 2-back test, hemodynamic changes within the prefrontal cortex were
assessed using high-density functional near-infrared spectroscopy. Scores of
the 2-back test, regardless of the exercise intensity, were positively
correlated with the hemodynamic changes within the right and left
dorsolateral prefrontal cortex (DLPFC). During an 2-back test, there were
differences in the hemodynamic changes within the DLPFC with moderate and
high-intensity exercise conditions. In the 2-back condition, the accumulated
oxyhemoglobin within the right DLPFC after moderate intensity exercise was
7.9% lower than that at baseline, while the accumulated
oxyhemoglobin within the left DLPFC was 14.6% higher than that at
baseline after high-intensity exercise. In response to the 2-back test, the
accumulated oxygenated hemoglobin within the left DLPFC after high-intensity
exercise increased more significantly than that observed after moderate
intensity exercise. These results show that the right DLPFC consumes O2 more
efficiently in response to moderate intensity aerobic exercise than in
response to high-intensity aerobic exercise.
Key words
aerobic exercise - near-infrared spectroscopy - oxygenated hemoglobin - dorsolateral
prefrontal cortex