Impact of Chronic Ankle Instability on Jumping and Agility in Athletes

Chronic ankle instability (CAI) is a frequent consequence of lateral ankle sprains, affecting up to 74% of athletes with previous ankle injuries. It is characterized by recurrent sprains, repeated "giving way" episodes, reduced function, and impaired performance. While CAI has been extensively studied in relation to balance and proprioception, its direct effects on sport-specific performance metrics such as jumping and agility remain less clear. In this cross-sectional case-control study, 32 athletes were enrolled: 16 athletes with CAI and 16 matched healthy athletes with no history of ankle instability. The CAI group was diagnosed using International Ankle Consortium (IAC) criteria (history of ≥1 lateral ankle sprain ≥12 months prior, ≥2 giving way episodes in the past 6 months, CAIT score ≤24, ≥5 years of sports participation). Controls had CAIT scores ≥25 and no ankle injury history. The testing battery included: Hop tests: single-leg hop, 6-meter timed hop, triple crossover hop, and lateral hop. Agility tests: 5-10-5 pro-agility shuttle and acceleration-deceleration-acceleration (ADA) test. Jump tests: countermovement jump (height, flight time, power) and side jump test. Measurements were supported by the Deepsport AI program for objective performance analysis.