Eccentric strengthening effect of hip-adductor training with elastic bands in soccer players: a randomised controlled trial
- Jesper Jensen1,
- Per Hölmich1,
- Thomas Bandholm2,
- Mette K Zebis3,
- Lars L Andersen4,
- Kristian Thorborg1
- 1Arthroscopic Centre Amager, Copenhagen University Hospital, Copenhagen, Denmark
- 2Clinical Research Center and Departments of Orthopedic Surgery and Physical Therapy, Copenhagen University Hospital, Hvidovre, Denmark
- 3Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
- 4National Research Centre for the Working Environment, Copenhagen, Denmark
- Correspondence to Dr Kristian Thorborg, Arthroscopic Centre Amager, Copenhagen University Hospital, Italiensvej 1, Copenhagen S 2300, Denmark;
Contributors In accordance with the Vancouver guidelines, all six authors have contributed to conception and design, acquisition of data or analysis and interpretation of data; drafting of the article or revising it critically for important intellectual content; and final approval of the version to be published.
- Received 26 February 2012
- Accepted 30 May 2012
- Published Online First 4 July 2012
Background Soccer players with weak hip-adductor muscles are at increased risk of sustaining groin injuries. Therefore, a simple hip-adductor strengthening programme for prevention of groin injuries is needed.
Objective We aimed to investigate the effect of an 8-week hip-adductor strengthening programme, including one hip-adduction exercise, on eccentric and isometric hip-adduction strength, using elastic bands as external load.
Methods Thirty-four healthy, sub-elite soccer players, mean (±SD) age of 22.1 (±3.3) years, were randomised to either training or control. During the mid-season break, the training group performed 8 weeks of supervised, progressive hip-adduction strength training using elastic bands. The participants performed two training sessions per week (weeks 1–2) with 3×15 repetition maximum loading (RM), three training sessions per week (weeks 3–6) with 3×10 RM and three training sessions per week (weeks 7–8) with 3×8 RM. Eccentric hip-adduction (EHAD), isometric hip-adduction (IHAD) and isometric hip-abduction (IHAB) strength, and the IHAD/IHAB ratio were measured assessor-blinded preintervention and postintervention, using reliable hand-held dynamometry procedures.
Results In the training group, EHAD strength increased by 30% (p<0.001). In the control group, EHAD strength increased by 17% (p<0.001), but the increase was significantly larger in the training group compared with the control group (p=0.044). No other significant between-group strength-differences in IHAD, IHAB or the IHAD/IHAB ratio existed (p>0.05).
Conclusions 8 weeks of hip-adduction strength training, using elastic bands, induce a relevant increase in eccentric hip-adduction strength in soccer players, and thus may have implications as a promising approach towards prevention of groin injuries in soccer.
Ethics approval The Danish Ethics Committee of the Capital Region (ID: H-4-2010-119) and the Danish Data Protection Agency (ID: 2007-58-0015).
Provenance and peer review Not commissioned; externally peer reviewed.