gms | German Medical Science

Objective: Knowledge of lower-extremity strength can be used in injury prevention, conditioning and rehabilitation of volleyball players. The goals were: (1) to describe the bilateral concentric and eccentric quadriceps (Q) and hamstrings (H) muscle strength in female volleyball players, (2) to evaluate strength ratios and bilateral strength asymmetry.

Material/Methods: A sample of 159 female volleyball players were tested on an isokinetic dynamometer TechnoGym REV 9000 at 60°/s to assess concentric and eccentric Q and H strength. We also calculated strength ratios and bilateral strength asymmetries. Strength assymetry was evaluated using repeated measures ANOVA for factors side, muscle and contraction type.

Results: The results are presented in Table 1 [Tab. 1]. The mean concentric strength ranged from 2.31–2.34 Nm/kg and 1.25–1.29 Nm/kg for quadriceps and hamstrings, respectively. As expected the eccentric strength values were significantly higher for both muscle groups. Classical strength ratio was 0.56 on average, while dynamic functional ratio was 0.61. There were no signs of bilateral strength asymmetry regardless of muscle group tested and contraction mode (F=3.84, p=0.052).

Conclusion: The results of our study are stressing the relative concnetric and eccentric weakness of hamstrings in female volleyball player that may predispose them to acute knee injuries (e.g. ACL rupture). This is best seen through the mean of low strength ratios. We believe that preventive training in female volleyball player should definitiely stress the hamstrings. Descriptive data about Q and H muscle function can be used as guidelines for coaches and therapists during training and rehabilitation of female volleyball players.