Effects of a Unilateral Strength and Plyometric Training Program for Division I Soccer Players

EFFECTS OF A UNILATERAL STRENGTH AND PLYOMETRIC TRAINING PROGRAM FOR DIVISION I SOCCER PLAYERS Eric Potter Old Dominion University, 2017 Director: Dr. Xihe Zhu The current thesis examined the effects of a unilateral strength and plyometric program on power (bilateral and unilateral vertical jumps), speed (20 meter sprint), and agility (Agility TTest) in collegiate soccer players compared to a traditional bilateral-based training program. Due to the fact that a majority of the research on performance variables in athletes is done using bilateral lifting and plyometric programs, yet most movements in field sports such as sprinting and changing direction are unilateral-based, this specific topic could have value for enhanced performance for athletic populations. The participants included 34 male and female Division-I soccer players who were paired up and then randomly assigned to a six week unilateral-based or bilateral-based training program. Pre and post tests were conducted prior to and after the six week training, respectively. In relation to pretest results, athletes’ bilateral vertical jump, unilateral vertical jump, 20 meter sprint, and T-Agility Test increased after six week training. The test scores were significantly correlated. Multivariate analysis of covariance results showed that pretest covariates were significant predictors for the corresponding posttest outcome, yet there was not a significant difference between the unilateral and bilateral training group’s improvements (Wilks’ λ = .88, F3,13 = .37, p = .86). Athletes in the unilateral training group scored slightly better than those in the bilateral training group, yet not significantly. This study demonstrated the value of a unilateral program on power, speed, and agility, but more research has to be conducted to determine if it could actually be a more optimal program than a traditional bilateral-based program. UNILATERAL TRAINING PROGRAM EFFECTS ON SOCCER PLAYERS iii Copyright, 2017, by Eric Potter, All rights Reserved UNILATERAL TRAINING PROGRAM EFFECTS ON SOCCER PLAYERS iv ACKNOWLEDGMENTS I would like to acknowledge many people who have contributed to the successful completion of this thesis. I extend many, many thanks to my committee members for their patience and guidance on my research and thorough editing of the thesis draft, particularly Dr. Xihe Zhu. Finally, I appreciate the contributing sport coaches, athletes, and entire university athletic department for the support and allowing me to conduct my research. UNILATERAL TRAINING PROGRAM EFFECTS ON SOCCER PLAYERS v