Postural stabilization after single-leg vertical jump in individuals with chronic ankle instability

Area of Science:

• Biomechanics
• Motor Control
• Sports Medicine

Background:

• Time to stabilization (TTS) analysis is crucial for assessing postural control.
• Defining the reference period for TTS calculations can influence outcomes.
• Chronic ankle instability (CAI) may affect postural control and balance.

Purpose of the Study:

• To examine how different reference balance definitions affect TTS analysis.
• To compare TTS between individuals with CAI and healthy controls post-jump.

Main Methods:

• Cross-sectional laboratory study.
• Fifty recreational athletes (25 CAI, 25 controls) participated.
• TTS and center of pressure (CoP) variability were measured after a maximal single-leg vertical jump, using single-leg stance, pre-jump, and post-jump periods as references.

Main Results:

• The post-jump reference period yielded lower TTS values in anterior-posterior and medio-lateral directions compared to single-leg stance and pre-jump.
• No significant differences in TTS were observed between the CAI and control groups.
• The CAI group exhibited greater CoP variability during the single-leg stance reference period.

Conclusions:

• The choice of reference period significantly influences TTS results.
• Post-jump balance recovery after a maximal vertical jump does not differ between individuals with CAI and healthy controls.
• Individuals with CAI demonstrate increased postural sway during static single-leg stance.