RT Journal Article SR Electronic T1 Mid-year review: physical inactivity universally accepted as the biggest public health problem of the 21st century, shoulder exam challenges, and progress against the scourges of anterior knee pain and ACL injuries 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 469 OP 470 DO 10.1136/bjsm.2009.062794 VO 43 IS 7 A1 K M Khan YR 2009 UL http://bjsm.bmj.com/content/43/7/469.abstract AB