Does Complex Training Enhance Vertical Jump Performance and Muscle Power in Elite Male Volleyball Players?

Purpose: The authors aimed to compare the effects of 4 weeks jump versus complex training methods on lower limb muscle power and maximal isokinetic torque of knee extensors and flexors in elite male volleyball players. Methods: Sixteen male volleyball players were allocated into 2 groups, jump training (n = 8; 27.0 [5.7] y, 94.3 [7.6] kg) and complex training (with induction of postactivation performance enhancement, n = 8; 26.6 [3.6] y, 94.2 [6.3] kg). All individuals performed jump training 2 sessions/wk, and the complex group received induction training with postactivation performance enhancement and jump training. Results: After 4 weeks, an increase in countermovement jump height (jump: 49.0 [1.2] to 52.7 [2.1] cm and complex: 49.2 [1.1] to 53.3 [1.9] cm; P=.009) and power (jump: 29.5 [1.1] to 34.3 [1.4] W and complex: 30.4 [0.9] to 34.4 [1.08] W; P= .001) was observed without significant differences between groups and without significant group x time interaction (P > .05). Also, no significant difference was observed between and within groups for the isokinetic peak torque at low speeds (60 and 180 degrees s), although total muscle work and knee extensor/flexor ratio increased from pretraining to posttraining at 300 degrees seconds similarly in both groups. Conclusion: The findings indicate that jump performance and power, knee extensor/flexor ratio, and total muscle work increased after 4 weeks of jump and complex training. However, the inclusion of heavy resistance stimulus did not elicit any additional improvements in the vertical jump performance and isokinetic strength of elite volleyball players.