RT Journal Article SR Electronic T1 Jill Cook 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 348 OP 348 DO 10.1136/bjsm.2006.031971 VO 41 IS 6 YR 2007 UL http://bjsm.bmj.com/content/41/6/348.abstract AB