Effects of eccentric exercise on optimum length of the knee flexors and extensors during the preseason in professional soccer players

Brughelli, Matt; Mendiguchia, Jurdan; Nosaka, Ken; Idoate, Fernando; Arcos, Asier Los; Cronin, John

doi:10.1016/j.ptsp.2009.12.002

« Previous Next »Physical Therapy in Sport
Volume 11, Issue 2 , Pages 50-55, May 2010

Effects of eccentric exercise on optimum length of the knee flexors and extensors during the preseason in professional soccer players

Matt Brughelli
- School of Exercise, Biomedical and Health Sciences, Edith Cowan University, 100 Joondalup Drive, Joondalup, Western Australia 6027, Australia
- Corresponding author. Tel.: +61 86304 5152; fax: +61 86304 5036.
Jurdan Mendiguchia
- Studies, Research and Sport Medicine Center (Government of Navarra), Department of Physical Therapy, C/Sanguesa 34 CP:3105 Pamplona, Spain
Ken Nosaka
- School of Exercise, Biomedical and Health Sciences, Edith Cowan University, 100 Joondalup Drive, Joondalup, Western Australia 6027, Australia
Fernando Idoate
- Department of Radiology, San Miguel Clinic, Pamplona, Spain
Asier Los Arcos
- Club Athletico Osasuna, Osasuna, Spain
John Cronin
- School of Exercise, Biomedical and Health Sciences, Edith Cowan University, 100 Joondalup Drive, Joondalup, Western Australia 6027, Australia
- Institute of Sport and Recreation Research New Zealand, AUT University, Auckland, New Zealand

Received 20 July 2009; received in revised form 2 November 2009; accepted 11 December 2009. published online 25 January 2010.

Abstract

Objective

To assess the effects of eccentric exercise on optimum lengths of the knee flexors and extensors during the preseason in professional soccer.

Design

Twenty-eight athletes from a professional Spanish soccer team (Division II) were randomly assigned to an eccentric exercise intervention group (EG) or a control group (CG). Over the four-week period two athletes from the control group suffered RF injuries and two athletes were contracted by other clubs. After these exclusions, both groups (EG, n=13; and CG, n=11) performed regular soccer training during the four-week preseason period.

Results

After the four weeks, the optimum lengths of the knee flexors were significantly (P<0.05) increased by 2.3° in the CG and by 4.0° in the EG. The change in the EG was significantly (P<0.05) greater than that of the CG. The optimum lengths of the knee extensors were significantly increased only in the EG by 6.5°. Peak torque levels and ratios of quadriceps to hamstring (Q/H ratios) were not significantly altered throughout the study for either group.

Conclusion

Eccentric exercise can increase the optimum lengths of both the knee extensors and knee extensors flexors during the preseason in professional soccer.

Keywords: Optimum angle, Hamstring injury, Rectus femoris injury, Eccentric intervention, Q/H ratio