RT Journal Article
SR Electronic
T1 Time-efficient intervention to improve older adolescents’ cardiorespiratory fitness: findings from the ‘Burn 2 Learn’ cluster randomised controlled trial
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 bjsports-2020-103277
DO 10.1136/bjsports-2020-103277
A1 David R Lubans
A1 Jordan J Smith
A1 Narelle Eather
A1 Angus A Leahy
A1 Philip J Morgan
A1 Chris Lonsdale
A1 Ronald C Plotnikoff
A1 Michael Nilsson
A1 Sarah G Kennedy
A1 Elizabeth G Holliday
A1 Natasha Weaver
A1 Michael Noetel
A1 Tatsuya T Shigeta
A1 Myrto F Mavilidi
A1 Sarah R Valkenborghs
A1 Prajwal Gyawali
A1 Frederick R Walker
A1 Sarah A Costigan
A1 Charles H Hillman
YR 2020
UL http://bjsm.bmj.com/content/early/2020/12/20/bjsports-2020-103277.abstract
AB Background Cardiorespiratory fitness (CRF) is an important marker of current and future health status. The primary aim of our study was to evaluate the impact of a time-efficient school-based intervention on older adolescents’ CRF.Methods Two-arm cluster randomised controlled trial conducted in two cohorts (February 2018 to February 2019 and February 2019 to February 2020) in New South Wales, Australia. Participants (N=670, 44.6% women, 16.0±0.43 years) from 20 secondary schools: 10 schools (337 participants) were randomised to the Burn 2 Learn (B2L) intervention and 10 schools (333 participants) to the control. Teachers in schools allocated to the B2L intervention were provided with training, resources, and support to facilitate the delivery of high-intensity interval training (HIIT) activity breaks during curriculum time. Teachers and students in the control group continued their usual practice. The primary outcome was CRF (20 m multi-stage fitness test). Secondary outcomes were muscular fitness, physical activity, hair cortisol concentrations, mental health and cognitive function. Outcomes were assessed at baseline, 6 months (primary end-point) and 12 months. Effects were estimated using mixed models accounting for clustering.Results We observed a group-by-time effect for CRF (difference=4.1 laps, 95% CI 1.8 to 6.4) at the primary end-point (6 months), but not at 12 months. At 6 months, group-by-time effects were found for muscular fitness, steps during school hours and cortisol.Conclusions Implementing HIIT during curricular time improved adolescents’ CRF and several secondary outcomes. Our findings suggest B2L is unlikely to be an effective approach unless teachers embed sessions within the school day.Trial registration number Australian New Zealand Clinical Trials Registry (ACTRN12618000293268).