P300, N400, aerobic fitness, and maximal aerobic exercise

Electrophysiological effects of aerobic fitness and maximal aerobic exercis e were investigated by comparing P300 and N400 before and after a maximal c ycling test. Event-related potentials (ERPs) were obtained from 20 students divided into two matched groups defined by their aerobic fitness level (cy clists vs. sedentary subjects). The session of post exercise ERPs was perfo rmed immediately after body temperature and heart rate returned to preexerc ise values. At rest, no significant differences were observed in ERP parame ters between cyclists and sedentary subjects. This finding argued against t he hypothesis that ERP modifications may be directly assumed by aerobic fit ness level. The postexercise session of ERPs showed a significant P300 ampl itude increase and a significant P300 latency decrease in all subjects. Sim ilarly. N400 effect increased significantly after the maximal exercise in a ll subjects. ERP changes were of the same magnitude in the two groups. The present study argues for a general arousing effect of maximal aerobic exerc ise, independently of the aerobic fitness level.