Effect of Functional Fatigue on Vertical Jump Height in Healthy Women and Men

Vertical jump is one of the basic sport activities and a popular test in the field of rehabilitation and sport which can assess the performance and power of lower extremity and musculoskeletal system. As fatigue is one of the factors that could increase the risk of injury, in this study the effect of fatigue on vertical jump was compared between healthy women and men.
18 women and 14 men performed the vertical jump before and after a functional fatigue protocol included 5 sets of consequent hops. Hopping consists stretch-shortening cycles which can mimic the natural behavior of muscle contraction in sport and daily living activities. Vertical jump height was studied variable in this research. Data were analyzed using repeated-measures analysis of variances (ANOVA) test.
No significant interaction between fatigue and group was observed for vertical jump height. Statistical analysis showed the greater value of jump height in men before and after the fatiguing condition. Furthermore, fatigue resulted in decrease in jump height value in both groups.
The main finding of this study was the similar response to fatigue in both groups. It seems that muscular fatigue prevents the proper muscular action to absorb the impact of landing. It results in more transfer of energy to the upper joints of lower extremity and increases the risk of injury.