Cycling Cleat Positioning Influences Achilles Tendon Strains, but at What Energetic Cost?

INTRODUCTION: Patellar and Achilles tendinopathy are overuse injuries associated with repetitive strain and often arise following sudden increases in exercise intensity and/or volume. As such, interventions that reduce tendon strain may represent effective methods for reducing overuse injury risk in this at-risk population of cyclists. One potential intervention is through the anterior/posterior positioning of the cycling cleat. METHODS: Ten recreational athletes, who were all novice cyclists, cycled on a stationary cycle ergometer at three cleat positions (neutral, 20 mm anterior, and 20 mm posterior), four power outputs (150, 200, 250, and 300 W), and two rider positions (seated and standing) for a total of 24 conditions. Motion capture and plantar-pressure data were collected, and peak Achilles and patellar tendon strains were obtained using musculoskeletal modeling. Metabolic output for each condition was also modeled using a combination of musculoskeletal modeling and a previously published metabolic model. RESULTS: Peak Achilles tendon strain was significantly reduced with a posterior cleat position compared with a neutral ( P = 0.047) and anterior ( P < 0.001) position during both standing and seated cycling. Peak patellar tendon strain ( P = 0.928) and modeled metabolic output ( P = 0.778), however, were not influenced by cleat position. CONCLUSIONS: Cycling with a 20 mm posterior cleat position represents an effective intervention for reducing the risk of developing Achilles tendinopathy without concurrently increasing patellar tendon strain or sacrificing performance.