Author(s): SEIPÄJÄRVI, S., NURMINEN, M., MUJUNEN, T., NUUTTILA, O.P., PIITULAINEN, H., KUJALA, J., KUMPULAINEN, S., KYRÖLÄINEN, H., PARVIAINEN, T., Institution: UNIVERSITY OF JYVÄSKYLÄ, Country: FINLAND, Abstract-ID: 513

INTRODUCTION:
Physical exercise is known to have long-term benefits for both physical and mental health. However, the physiological and neural responses to exercise depend on its characteristics, such as intensity and duration. During exercise, the brain continuously monitors bodily states and regulates processes required for ongoing movement. Neural mechanisms underlying these processes can be studied through brain oscillatory activity. In particular, sensorimotor cortex exhibits characteristic alpha (8–13 Hz; mu) and beta (13–30 Hz) rhythms associated with movement planning, sensory processing, and execution. Frontal brain regions are involved in higher-order control processes, such as evaluating bodily resources and regulating effort during exercise. The present study aimed to examine how acute 90-minute endurance exercise affects brain oscillatory activity measured at rest.
METHODS:
Nineteen healthy adults (9F/10M) completed three visits: a pre-test including an incremental running test, and two experimental visits consisting of either 90 minutes of running or 90 minutes of free reading/music listening. Running speed was individually determined from the pre-test. Resting-state magnetoencephalography (MEG), heart rate and heart rate variability, blood lactate, Feeling Scale, and Felt Arousal Scale were measured before and at 10 and 55 minutes after condition. Brain oscillatory activity was analyzed using Dynamic Imaging of Coherent Sources (DICS). Exercise-specific effects in the brain oscillatory power were studied by contrasting both within- and between session changes, e.g: RUN (POST10-PRE) – CON (POST10-PRE) and utilizing a source-level cluster-based permutation test with a maximum-statistics approach.
RESULTS:
Running increased heart rate and blood lactate and decreased heart rate variability compared with the control session, while perceived arousal decreased after both sessions. Exercise-specific changes in oscillatory power were observed across multiple frequency bands and cortical regions. Alpha power decreased immediately after running and increased at 55 minutes post-exercise above pre-exercise levels. Low beta (13–20 Hz) power decreased after running and remained reduced at 55 minutes post-exercise. Alpha and low beta responses were seen primarily in frontal and insular regions. High beta (20–30 Hz) power increased in the sensorimotor cortex after running and returned toward baseline at 55 minutes post-exercise. Oscillatory changes correlated with blood lactate and perceived exertion.
CONCLUSION:
In conclusion, our results demonstrate exercise-specific modulations in oscillatory power across several brain regions including sensorimotor, frontal and insular regions. These modulations appear to follow a distinct timeline, likely reflecting ongoing recovery processes in both the body and brain after a demanding bout of exercise. Also the magnitude of exercise-induced psychophysiological stress appears to influence these oscillatory responses.