300 Section - The Effects of Aerobic Exercise on Executive Function Performance, Cerebral Cortical Activation and Network Efficiency Under Extreme Heat Conditions: A Study Based on Functional Near-Infrared Spectroscopy (fNIRS)

Objectives : The present study aims to investigate the effects of aerobic exercise in extreme heat conditions (38°C) on executive function performance, cortical activation, and network efficiency.

Design: A total of 11 healthy male participants were recruited and enrolled in the study, with the exclusion criteria being met by all participants. The experiment was conducted within an environmentally controlled chamber, the purpose of which was to ensure that the temperature and humidity levels met the specified standards (ambient temperature 38°C, humidity 60%). The acquisition of fNIRS data was initiated prior to the commencement of the experiment, and occurred during the performance of the Stroop task. Participants were instructed to perform aerobic exercise (brisk walking) at a speed of 6 km/h on a treadmill with zero incline. Skin temperature, ear temperature, and heart rate were meticulously monitored throughout the exercise session. The experiment was terminated immediately if any of the following occurred: (1) ear temperature reached 40°C; (2) Heart rate exceeding 90% of maximum heart rate; (3) Participant exhaustion. fNIRS data collection for the Stroop task resumed immediately post-exercise.

Results: Post-intervention reaction times and accuracy in the Stroop task were lower than pre-intervention levels, with no significant difference in interference effects between the two stages. Brain activity analysis revealed lower HbO₂ levels in key regions post-intervention. Network efficiency metrics showed higher Eloc post-intervention. A positive correlation was identified between HbO₂ levels in the left Broca region and the interference effect during the Stroop task.

Conclusion: In the context of extreme heat conditions, the performance of aerobic exercise in healthy individuals has been observed to result in a decline in the concentration of oxyhaemoglobin in cognition-related cortical areas. This decline has been associated with a subsequent impairment in cognitive performance and an enhancement in local network efficiency.