Impact Biomechanics Reveal Positional and Session Type Differences in Canadian Collegiate Football.

Frequent head impacts are common in Canadian football, yet the biomechanical determinants underlying repeated subconcussive exposure and their potential implications remain poorly characterized. To address this, we investigated the biomechanical impact characteristics of college-level Canadian varsity football players, aiming to elucidate the underlying factors that drive subconcussive impacts. Sixty-four athletes were outfitted with head impact sensors during games, practices, and training camps. We examined impact frequency, peak linear and rotational acceleration, impact duration, area under the acceleration-time curve (AUAC), impulse, and head jerk, grouping participants as small skill (SS), big skill (BS), or linemen (LN). Significant differences emerged based on both player position and session type. Linemen experienced the highest AUAC and impulse values, whereas SS and BS positions were associated with less frequent but higher-magnitude impacts. Session type further influenced exposure, with games producing greater peak accelerations and longer impact durations than practices or training camps. These results demonstrate that analyzing linear acceleration time series reveals more nuanced insights into the complex dynamics of subconcussive impacts than peak magnitudes alone. Such analyses establish a critical foundation for linking biomechanical parameters to injury risk and neurophysiological biomarkers, ultimately informing data-driven strategies to enhance athlete safety in contact sports.