Ankle bracing, fatigue, and time to stabilization in collegiate volleyball athletes.

CONTEXT: Fatigue has been shown to disrupt dynamic stability in healthy volunteers. It is not known if wearing prophylactic ankle supports can improve dynamic stability in fatigued athletes.

OBJECTIVE

To determine the type of ankle brace that may be more effective at providing dynamic stability after a jump-landing task during normal and fatigued conditions.

DESIGN

Two separate repeated-measures analyses of variance with 2 within-subjects factors (condition and time) were performed for each dependent variable.

SETTING

Research laboratory.

PATIENTS OR OTHER

PARTICIPANTS

Ten healthy female collegiate volleyball athletes participated (age = 19.5 +/- 1.27 years, height = 179.07 +/- 7.6 cm, mass = 69.86 +/- 5.42 kg).

INTERVENTION(S): Athletes participated in 3 separate testing sessions, applying a different bracing condition at each session: no brace (NB), Swede-O Universal lace-up ankle brace (AB), and Active Ankle brace (AA). Three trials of a jump-landing task were performed under each condition before and after induced functional fatigue. The jump-landing task consisted of a single-leg landing onto a force plate from a height equivalent to 50% of each participant's maximal jump height and from a starting position 70 cm from the center of the force plate.

MAIN OUTCOME MEASURE(S): Time to stabilization in the anterior-posterior (APTTS) and medial-lateral (MLTTS) directions.

RESULTS

For APTTS, a condition-by-time interaction existed (F(2,18) = 5.55, P = .013). For the AA condition, Tukey post hoc testing revealed faster pretest (2.734 +/- 0.331 seconds) APTTS than posttest (3.817 +/- 0.263 seconds). Post hoc testing also revealed that the AB condition provided faster APTTS (2.492 +/- 0.271 seconds) than AA (3.817 +/- 0.263 seconds) and NB (3.341 +/- 0.339 seconds) conditions during posttesting. No statistically significant findings were associated with MLTTS.

CONCLUSIONS

Fatigue increased APTTS for the AA condition. Because the AB condition was more effective than the other 2 conditions during the posttesting, the AB appears to be the best option for providing dynamic stability in the anterior-posterior direction during a landing task.