Context:

There is limited information on fatigue of the evertors on frontal plane joint position sense (JPS).

Objective:

To examine the effects of isokinetic concentric-eccentric fatigue of the evertors on frontal plane JPS of the ankle.

Design:

A 2 × 4 factorial design.

Setting:

Research Laboratory.

Patients or Other Participants:

40 male and female healthy subjects.

Interventions:

JPS was tested at 10° and 20° of inversion and 5° and 10° of eversion in a nonfatigued/fatigued condition. After fatigue of evertors was determined on an isokinetic device, post fatigue testing of JPS occurred.

Main Outcome Measures:

JPS absolute error (AE) for inversion and eversion.

Results:

Main effect for condition and angle were significant with pre/post fatigue. There were overestimation of angles postfatigue with AE greater at 20° of inversion (P = .003), followed by 10° of inversion (P < .001), 10° of eversion (P = .005), and 5° of eversion (P = .005).

Conclusion:

When the ankle evertors were fatigued, the AE for JPS was significantly higher at all test angles.