RT Journal Article SR Electronic T1 Discussion 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 157 OP 157 DO 10.1136/bjsm.10.3.157 VO 10 IS 3 YR 1976 UL http://bjsm.bmj.com/content/10/3/157.abstract AB