Objective To determine if adolescent athletes with a history of lateral ankle sprain(s) (LAS) displayed deficits on functional performance tests (FPTs) and if deficits on FPT were related to the number of previous LAS. Design Cross-sectional study. Setting Biomechanics Laboratory. Participants The injured group (n = 24) had a history of ≥1 moderate-severe LAS. The uninjured group (n = 34) had no history of LAS. Main outcome measure(s) The average reach distance of three trials in each direction of the star excursion balance test (SEBT) was normalized to leg length (%). The average of two trials of single-leg-hop test (SLHT) was calculated in seconds. Results The injured group performed significantly worse in 3 directions of SEBT than the uninjured group (P \u3c 0.05). SLHT was significantly slower in the injured group compared to the uninjured group (P \u3c 0.05). Statistically significant, strong to moderate inverse relationships were found between the numbers of LAS and each of the three directions of the SEBT (P ≤ 0.01). No relationship was revealed between the number of LAS and the SLHT (P \u3e 0.05). Conclusion(s) Adolescent athletes with a history of LAS exhibit functional performance deficits on the SEBT and SLHT. Therefore, the SEBT and SLHT may provide clinicians cost- and time-effective objective tools
