Ultramarathon racing elicits changes in behavioural and electroencephalographic indices of executive function

The purpose of this study was to determine whether racing a 50-km ultramarathon alters behavioural and electrophysiological (EEG) indices of executive function. Seventy-six recreational runners (37 ± 10 y; 39 F, 37 M) completed EEG assessments before and immediately after the race at one of six ultramarathons. Executive function was evaluated using a visual oddball task, with accuracy and reaction time as behavioural markers, N2 as an index of inhibitory control, and P3 as an index of attentional allocation. Motivation (SMS) and negative affect (DASS-21) were assessed 7–14 days before the race. Average race time was 7 h 54 min (± 2 h 8 min), with 2.5% (± 1.7%) body-mass loss. Reaction times were 2.2% shorter post-race (p < .0001) alongside a 14% increase in variability (p < .0001). N2 and P3 amplitudes decreased by 28.1% (p = .008) and 17.9% (p < .0001), respectively, with P3 latency reduced 3.4% (p < .001). Larger N2 reductions were associated with higher identified (r = .29, p = .013) and introjected (r = .29, p = .012) motivation, while greater P3 reductions correlated with higher DASS-21 scores (r = –.69, p < .001). Racing an ultramarathon reduced neural activity related to inhibitory control and attentional allocation, resulting in shorter, more variable behavioural responses. Associations with affective state and motivation subtypes measured in the weeks prior suggest that pre-race psychological factors may influence cognitive resilience during ultramarathon competition.