RT Journal Article SR Electronic T1 Risk factors for hamstring muscle strain injury in sport: a systematic review and meta-analysis JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP 351 OP 358 DO 10.1136/bjsports-2011-090664 VO 47 IS 6 A1 Grant Freckleton A1 Tania Pizzari YR 2013 UL http://bjsm.bmj.com/content/47/6/351.abstract AB