RT Journal Article SR Electronic T1 Sports Medicine 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 63 OP 63 DO 10.1136/bjsm.28.1.63 VO 28 IS 1 A1 R. G. Hackney YR 1994 UL http://bjsm.bmj.com/content/28/1/63.1.abstract AB