Association Between Jump Height And Lower Extremity Flexibility In Collegiate Volleyball Players

Vertical jump height is a critical skill in volleyball, as it directly affects a player's ability to attack, block, and serve effectively. Plyometric training programs often seek to improve jump height, an outcome that can be easily monitored and evaluated, and this is often accomplished through the prescription of explosive-type movements. Additionally, measures of lower extremity flexibility may be associated with injury risk and typical training paradigms often include exercises intended to increase flexibility. The stretch-shortening cycle (SSC) is a key factor in explosive movements like vertical jumping, where muscles rapidly stretch and shorten to generate power and this may be influenced by lower extremity flexibility. PURPOSE: To determine the relationship between vertical jump height and lower extremity flexibility in collegiate women’s volleyball players. METHODS: Sixteen NCAA DII women’s volleyball athletes completed a lower body flexibility and vertical jump height assessment during one testing session. After a five-minute warm-up, the participants completed three trials of the sit-and-reach test with 30s of rest in between each attempt with the highest value being recorded. Following this, participants completed three countermovement jump trials using the Just Jump System in which they were instructed to jump as high as possible while reaching towards the ceiling and landing back on the mat. Thirty seconds of rest were given between each trial and the highest jump height of the three trials was recorded. The relationship between sit-and-reach distance and jump height was evaluated utilizing the Pearson correlation coefficient with an a priori alpha level of 0.05. RESULTS: There was a significant, positive correlation between sit-and-reach distance and jump height (P = 0.011, r = 0.614). CONCLUSIONS: This finding suggests that lower body flexibility may play a role in vertical jump performance, possibly by influencing the SSC. This highlights the potential for flexibility training to be integrated into plyometric programing in attempts to further improve explosive movements like jumping. Future research should explore whether targeted flexibility interventions can produce direct improvements in jump height and whether this relationship exists across different populations and sports.