MCGREGOR, G., NICHOLS, S., HAMBORG, T. et al. 2016. High-intensity interval training versus moderate-intensity steady-state training in UK cardiac rehabilitation programmes (HIIT or MISS UK): study protocol for a multicentre randomised controlled trial and economic evaluation. [Protocol]. BMJ open [online], 6(11), article number e012843. Available from: https://doi.org/10.1136/bmjopen-2016-012843