Risk Factors of Lower Extremity Injuries and Sport Performance Following Functional Training in Young Soccer Players: Randomized Clinical Trial

Document Type : Original Articles


1 Assistant Professor, Department of Sport Science, Sirjan University of Technology, Kerman, Iran

2 Assistant Professor, Department of Sports Injuries and Corrective Exercises, Asrar Institute of Higher Education, Mashhad, Iran



Introduction: As a result of insufficient neuromuscular adaptation, dynamic lower extremity alignment is exposed to biomechanical deficits in loading tasks. Therefore, in addition to neuromuscular retraining and decreasing risk of injuries, sport performance indices should be considered while designing injury prevention programs. This study aimed to investigate the effect of 10-week soccer-specific functional training (SSFT) on risk factors of lower extremity injuries and sport performance indices concurrently in young male soccer players.Materials and Methods: In this randomized controlled trial, 27 young male soccer players were randomly allocated into a control group (n = 13) and experimental group (n = 14). The control group continued their regular soccer training. For experimental group, 3 sessions of SSFT were weekly introduced whitin their regular soccer training program for 10 weeks. SSFT included strength, balance, core, plyometrics, speed and agility exercises as well as the soccer-specific drills. Measurements consisted of the Landing Error Scoring System (LESS) and general and sport-specific performance tests including sprint, agility, power, balance, strength, and best and average time of Shuttle Sprint and Dribble Test (SDT) before and after SSFT in both groups. Analysis of covariance (ANCOVA) was used for statistical analysis (P < 0.05).Results: From the pre-test to post-test, LESS score, time in 30-m test, arrowhead test, and average SDT in experimental group decreased significantly compared to control group (P < 0.001). Similarly, the improvement in experimental group was statistically significant for the countermovement-jump test, Y-Balance Test (YBT), and one-repetition maximum (1RM) tests (P < 0.001) compared to that in control group. The best SDT time was not significantly better in experimental group (P > 0.05).Conclusion: SSFT designed based on functional capacity can be effective in reducing some risk factors of lower extremity injuries and improving sport performance in young male soccer players.


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  • Receive Date: 13 July 2020
  • Revise Date: 02 June 2022
  • Accept Date: 22 May 2022