Abstract

Purpose. To compare the effects of plyometrics, closed kinetic chain with quadratus lumborum strengthening exercises on vertical jump height in volley ball players.

Design. Pre-post measurement randomized controlled trial.

Methods. Two hundred volleyball players were recruited from Cairo and Kafer El Sheikh University, Egypt. 140 volleyball players met the inclusion criteria and were randomly assigned into four equal groups. Group (A) consisted of 35 volley ball players with mean body mass index (BMI) value of 21 ± 3.76 kg/m2 and received plyometric exercise (Counter Movement jump (CMJ). Group (B) consisted of 35 volley ball players with mean BMI value of 21.44 ± 1.681 kg/m2 and received closed kinetic chain (CKC) exercise (double limp squat free weights), Group (C) consisted of 35 volley ball players with mean BMI value 22.17 ± 1.8 kg/m2 and received quadratus lumorum strengthening exercise (isotonic hip hiking), group (A), (B) and (C) received the exercises two times per week for eight weeks. Group (D) consisted of 35 volley ball players with mean BMI value of 22.01 ± 1.69 kg/m2 and received no exercise (control group).

Results. Statistical analysis revealed that there was significant difference (p < 0.05) in favour to group A, B and C in compared to group D. while there were no significant differences (p > 0.05) among groups (A, B and C).

Conclusion. Plyometrics (CMJ), CKC (Double limb squat free weights), and quadratus lumborum strengthening exercise (Hip hiking) yield an improvement on vertical jump height.

Key words:

plyometrics, CKC, vertical jump, strengthening exercise