Table 1

Summary of the evidence for hamstrings strength, hip ROM, previous injury of the same type, and age as risk factors for hamstring strains. The table also shows whether a multivariate approach was used to analyse the data

StudySport (n)Total sample 
 size (n)No. of injured athletes 
 (n, % per season)Strength*ROM*Previous injury*Other internal risk factors studiedDesign (study type, statistical approach)†
*+, significant association; −, no significant association observed; NA, not applicable (case-control studies). †Univariate indicates that t test or similar were used for continuous variable, and χ2-tests or similar were used for categorical variables. Multivariate indicates that logistic regression analysis or discriminant analysis were used.
Burkett (1970)39Athletics & soccer30 + 37+NACase-control
Liemohn (1978)58Athletics277 (26%)++Cohort, univariate
Worrell et al. (1991)40Football, soccer, lacrosse & athletics3216 cases & 
 16 controls+NACase-control, univariate
Yamamoto (1993)59Athletics6426 (20%)+Cohort, univariate
Jönhagen et al. (1994)41Athletics (sprinters)2011 cases & 
 9 controls++NACase-control, univariate
Orchard et al. (1997)60Australian rules football376 (16%)+Age, height, weight, body composition, aerobic & anaerobic fitness, etc.Cohort, uni- & multivariate
Bennell et al. (1998)42Australian rules football10212 (12%)+Cohort, univariate
Fredriksen (1998)61Athletics (sprinters)196 (32%)+Cohort, univariate
Verrall et al. (2001)50Australian rules football11426 (23%)+Age, height, weight, race, previous knee, back or groin injuryCohort, univariate
Orchard (2001)51Australian rules football83503 player-games672 injuries+Age, height, weight, body mass index, raceCohort, uni- & multivariate
Arnason et al. (2003)44Soccer30631 (10%)+Age, height, weight, body composition, aerobic fitness, jumping ability, etc.Cohort, uni- & multivariate