RT Journal Article SR Electronic T1 The association between moderate and vigorous physical activity and time to medical clearance to return to play following sport-related concussion in youth ice-hockey players 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 A44 OP A44 DO 10.1136/bjsports-2016-097270.112 VO 51 IS 11 A1 Justin Lishchynsky A1 Luz Palacios-Derflinger A1 Clodagh Toomey A1 Carolyn Emery A1 Keith Yeates A1 Willem Meeuwisse A1 Kathryn Schneider YR 2017 UL http://bjsm.bmj.com/content/51/11/A44.1.abstract AB Objective The objective of this study was to determine if youth ice-hockey players who perform more moderate and vigorous physical activity (MVPA) during recovery take longer to achieve medical clearance to return to play (RTP).Design Cohort study.Setting Sport Medicine Centre, Alberta, Canada.Participants Thirty youth ice-hockey players [25 males, 5 females, median age 14 years (range 12–17)] presenting to a sport medicine clinic within 4 days (range 2–20 days) of sustaining a sport-related concussion diagnosed by a sport medicine physician.Exposure Participants MVPA during the first three days following their initial appointment was measured using a waist worn Actigraph accelerometer. MVPA was dichotomized into high (≥45 minutes) and low (<45 minutes) activity based on the median daily MVPA.Outcome The primary outcome was time (days) to medical clearance to RTP.Results All thirty participants performed at least some MVPA over the first three days, despite physician instruction to initially rest following the concussion. Players performing low levels of MVPA reached medical clearance in a median of 15 days (range: 10–30 days). Players performing high levels of MVPA reached medical clearance in a median of 19 days (range: 12–55 days). The low level MVPA group reached medical clearance significantly sooner than the high activity group (log-rank chi2=5.27, p=0.02).Conclusions More time in MVPA during the first three days after initial assessment is significantly associated with greater time to medical clearance to RTP. Future research is needed to better understand the optimal amount and timing of MVPA for concussion recovery.Competing interests None.