Smith, B. E., Hendrick, P., Smith, T. O., Bateman, M., Moffatt, F., Rathleff, M. S., …Logan, P. (2017). Should exercises be painful in the management of chronic musculoskeletal pain?: a systematic review and meta-analysis. British Journal of Sports Medicine, 51(23), https://doi.org/10.1136/bjsports-2016-097383