RT Journal Article SR Electronic T1 Sport and exercise: the public health challenge 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 409 OP 410 DO 10.1136/bjsm.34.6.409 VO 34 IS 6 A1 Liam J Donaldson YR 2000 UL http://bjsm.bmj.com/content/34/6/409.abstract AB