Neurophysiology of Downhill Mountain Bike Athletes-Benchmark Assessments of Event-Related Potentials.

Background: Downhill mountain biking (MTB) is a high-velocity sport where riders are potentially exposed to impacts and concussion. Rapidly obtained Event-Related Potentials (ERPs) are a promising use of portable electroencephalography for clinical assessment of concussion-related neurological impairment at the point of care. However, the baseline neuroelectric profile of this specific sporting population is not fully understood. This study investigated the amplitude and latency of the N100, P300 and N400 ERPs at baseline among MTB athletes by age, sex and caffeine consumption. Methods: MTB athletes, aged 13-45, competing in the 2024 Whistler Crankworx MTB competition were recruited for this cross-sectional analysis. Self-reported sex, age and caffeine consumption were captured and pre-event baseline neurological evaluations of the N100, P300 and N400 ERPs (n = 92) were completed using a portable electroencephalograph (NeuroCatch). Results: Females had a 1.12 µV higher N100 amplitude (95%CI; 0.15, 2.08, p = 0.024) and 2.11 µV higher P300 amplitude (95%CI; 0.69, 3.52, p = 0.004) than males. Further, the N400 amplitude was 0.05 µV lower per year that age increases (95%CI; -0.08, -0.01, p = 0.011). Greater than normal caffeine consumption was associated with a 1.39 µV lower (95%CI; -2.68, -0.09, p = 0.036) and 18.96 ms (-28.29, -9.64, p < 0.001) faster N100 response. Conclusions: Age, sex and caffeine consumption must be considered to inform the clinical implement of ERPs for monitoring concussion in extreme sport athletes.