The Effect of the “11+ Kids” Program on the Isokinetic Strength of Young Football Players
in International Journal of Sports Physiology and PerformanceClick name to view affiliation
Search for other papers by Mostafa Zarei in
Current site
Google Scholar
PubMed
Search for other papers by Hamed Abbasi in
Current site
Google Scholar
PubMed
Search for other papers by Abdolhamid Daneshjoo in
Current site
Google Scholar
PubMed
Search for other papers by Mehdi Gheitasi in
Current site
Google Scholar
PubMed
Search for other papers by Kamran Johari in
Current site
Google Scholar
PubMed
Search for other papers by Oliver Faude in
Current site
Google Scholar
PubMed
Search for other papers by Nikki Rommers in
Current site
Google Scholar
PubMed
Search for other papers by Roland Rössler in
Current site
Google Scholar
PubMed
Purpose: The “11+ Kids” injury-prevention program has been shown to reduce injuries and related costs in youth football players less than 14 y of age. A major argument to convince coaches to use this exercise-based injury-prevention program is a potential performance enhancement of the players. Therefore, this study investigated the effects of the “11+ Kids” program on isokinetic strength. Methods: Two teams were randomly assigned to the intervention and control groups. The intervention group replaced their warm-up by the “11+ Kids” and the control group warmed up as usual. Two days before and after the 10-wk intervention, isokinetic strength of the hip adductors and abductors, knee flexors and extensors, and ankle invertors and evertors was tested. Results: Thirty-one players (mean age 11.5 [0.8] y) completed the study. The intervention group showed large improvements in all isokinetic strength measures (P < .001 for all measures; Cohen d = 0.8–1.4), whereas the control group only showed negligible to medium positive effects (P values ranging from .006 to .718; Cohen d = −0.1 to 0.7). The intervention was beneficial compared with the control group regarding isokinetic strength of the hip adductors (P < .001), knee flexors (P = .002), and ankle evertors (P < .001) and invertors (P = .005). Conclusions: Given the relatively short intervention period of 10 wk, the observed improvements relate to a practically meaningful effect of the intervention. The gain in strength may improve players’ performance and may contribute to a reduction of injury risk in the long-term application.
Zarei and Gheitasi are with the Dept of Physical Education and Sports Sciences, Shahid Beheshti University, Tehran, Iran. Abbasi is with the Dept of Sport Injuries and Corrective Exercises, Sport Sciences Research Inst, Tehran, Iran. Daneshjoo is with the Dept of Physical Education and Sports Sciences, Shahid Bahonar University of Kerman, Kerman, Iran. Johari is with the Dept of Physical Education, Islamic Azad University, Branch Bukan, Bukan, Iran. Faude and Rössler are with the Dept of Sport, Exercise and Health, University of Basel, Basel, Switzerland. Rommers is with the Dept of Movement and Sports Sciences, Vrije Universiteit Brussel, Brussels, Belgium; the Dept of Movement and Sports Sciences, Ghent University, Ghent, Belgium; and Research Foundation—Flanders (FWO), Brussels, Belgium. Rommers and Rössler are also with the Dept of Public and Occupational Health, Amsterdam Public Health Research Inst, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands.
© 2023 Human Kinetics