Effects of Peroneal Muscle Fatigue on Ground Reaction Force Profile During Lateral Hop Landing

Abstract

Introduction: Ankle sprain occurs often late in sport competitions consisting of many lateral ankle movements, jumping or landing, where peroneal muscles are fatigued. Changes in Ground Reaction Force (GRF) parameters may also be related to this injury. The present study aimed to assess the effects of peroneal muscles fatigue on GRF profile during lateral hop landing. Materials and Methods: Twenty-five recreationally active healthy males performed a lateral hop on a force plate before and after a fatigue intervention by a Biodex dynamometer using an isometric eversion at 40% of maximal voluntary isometric contraction until eversion torque decreased to 50% of its initial value. A force plate and an EMG system were used to collect data during lateral hop landing. Results: Fatigue was confirmed by a significant fall in median frequency (P<0.05). Mean of the normalized peak GRF in the vertical direction, mean of the normalized impulse of the GRF in the vertical direction, and means of the time to peak GRF in the vertical and mediolateral directions decreased significantly after fatigue (P<0.05). Conclusion: If the peroneal muscles are fatigued, a much more load may transfer to the vertical direction during landing, although the vulnerable part of the ankle is situated on the mediolateral direction.

Keywords

• Hopping
• Loading rate
• Impulse
• Sports injury