Increasing Step Frequency Reduces Patellofemoral Joint Stress and Patellar Tendon Force Impulse More at Low Running Speed.

Purpose: Patellofemoral pain syndrome and patellar tendinopathy are important running-related overuse injuries. This study investigated the interaction of running speed and step frequency alterations on peak and cumulative patellofemoral joint stress (PFJS) and patellar tendon force (PTF) parameters.

Methods: Twelve healthy individuals completed an incremental running speed protocol on a treadmill at habitual, increased and decreased step frequency.