Advances in wearable technology have improved the ability to measure spatiotemporal gait parameters and training metrics in real-world environments, providing greater insight into how runners accumulate mechanical load. While spatiotemporal parameters such as velocity and cadence are associated with tibial acceleration (TA), these relationships have typically been examined at fixed velocities under controlled conditions, and do not consider their potential interaction or reflect real-world running conditions. The purpose of this study was to investigate the association between running velocity, cadence and TA in an outdoor environment. One hundred recreational runners ran on an athletics track at five velocities, ranging from very slow to very fast, based on their self-selected training pace. The results showed a significant interaction effect between cadence and velocity for both axial (p=0.002) and resultant TA (p<0.001). The estimated increase in axial TA for every 1-step increase in cadence ranged from 0.017 g to 0.042 g across the five velocity bands. For resultant TA, the estimated increase ranged from 0.006 g to 0.082 g. These findings suggest that cadence had a larger effect on TA at faster velocities, highlighting the importance of monitoring cadence in conjunction with velocity to inform TA.