Several researchers have suggested that improving evertor strength and peroneus longus reaction time may help alleviate the symptoms of chronic ankle instability and reduce the rate of recurrent ankle sprains.
To determine the effectiveness of a 4-wk elastic-resistance exercise-training program on ankle-evertor strength and peroneus longus latency in subjects with and without a history of ankle sprains (HAS).
Randomized controlled clinical trial.
40 subjects (20 male, 20 female; 20 HAS, 20 healthy). Ten subjects (5 male and 5 female) from each of the HAS and healthy groups were randomly assigned to exercise or control groups.
4-directional elastic-resistance exercise training 2 times/wk for 4 wk.
Main Outcome Measures:
Ankle-evertor strength and peroneal muscle latency after sudden inversion were measured before training, after 4 wk of training, and 4 wk posttraining.
Four weeks of elastic-resistance exercise training did not elicit significant changes in 1-repetition-maximum ankle-evertor strength between the exercise and control groups (P = .262), HAS and healthy groups (P = .329), or males and females (P = .927). Elastic-resistance exercise training did not elicit significant changes in peroneus longus muscle latency between the exercise and control groups (P = .102), HAS and healthy groups (P = .996), or males and females (P = .947).
The 4-wk elastic-resistance exercise training had no effect on ankle-evertor strength and reflex latency of the peroneus longus after unexpected ankle inversion.