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Fitness/Health

(70) ASSESSING DIFFERENCES IN DROP JUMP PERFORMANCE BETWEEN CHRONIC ANKLE INSTABILITY AND HEALTHY ANKLE JOINTS

Friday, July 14, 2023
10:30 AM - 12:00 PM East Coast USA Time
Location: Milano III-IV
Abstract Details: It is important to investigate the jumping ability of individuals with chronic ankle instability (CAI) as previous research has demonstrated its prevalence in athletic events that involve high levels of jumping. To date, only one study has evaluated the jumping ability of individuals with CAI, which was evaluated using drop jumps. However, it is crucial to assess individuals with CAI using drop jumps that include frontal plane movements since CAI has been shown to be significantly affected by forehead movements. PURPOSE This study aimed to determine differences in single-leg drop jump performance from the anterior frontal and sagittal planes between individuals with CAI and those with healthy feet. METHODS College male basketball players were classified into those with CAI and those without a history of ankle sprain, according to the International Ankle Consortium, and 12 pairs were selected for the experiment. Three types of single-leg drop jumps were tested, a sagittal drop jump, a lateral drop jump, and a medial drop jump, and performance indices were calculated. A force plate (Kistler) was used to measure jump height, ground contact time, reactive strength index, maximum vertical ground reaction force, rate of force development, and vertical force product of the ground plane. The percent maximum voluntary contraction of the peroneus longus, tibialis anterior, and medial head of gastrocnemius muscles during the trial was measured using a surface electromyograph (ME6000TS, Meg Electronics). A two-factor two-way ANOVA was used for statistical analysis. RESULTS The results showed a significant difference in jump height and reactive strength index during medial drop jumps between the group with normal feet and the group with CAI (p< 0.05) (Figure 1). In addition, we found a significant difference in peroneus longus muscle activity in the ground plane during all three trials between the group with normal feet group and the group with CAI (p< 0.05) (Figure 2). CONCLUSIONS The findings suggest that individuals with CAI have less muscle activity in the peroneus longus during drop jumps compared to those without a previous ankle sprain, which may also affect the jumping height of the medial landing jumping motion. PRACTICAL APPLICATION In the rehabilitation and training of those with CAI, it is important to increase muscle activity in the peroneus longus, especially in competitions involving jumping movements.

Acknowledgements: None