Introduction Exercise capacity has been established as a protective factor against joint impairment in people with haemophilia (PWH). However, little is known about how exercise capacity is affected in PWH. Aim To analyse exercise capacity, as assessed by standardised laboratory or field tests in PWH. Methods A systematic review was conducted to identify manuscripts investigating physical capacity in PWH. An electronic search of PubMed/MEDLINE, Embase, Web of Science, CENTRAL and CINAHL was conducted from inception to 13 April, 2022. Two independent reviewers performed data extraction and assessed study quality using the critical appraisal tools of the Joanna Briggs Institute. Results Nineteen studies with 825 patients were included. Most studies used the six-min walk test (6MWT) or peak/maximal oxygen consumption (VO(2)max). In children, the distance walked ranged from 274 +/- 36.02 to 680 +/- 100 m. In adults, the distance walked ranged from 457.5 +/- 96.9 to 650.9 +/- 180.3 m. VO(2)max ranged from 37 +/- 8 to 47.42 +/- 8.29 ml kg(-1) min(-1). Most studies reported lower values of exercise capacity compared to standardised values. Overall, the quality of the studies was moderate. Conclusion Most of the studies showed that PWH have lower exercise capacity compared to reference values of 6MWT or VO(2)max. Based on these results, it is necessary to emphasise in both the promotion and the prescription of physical exercise in PWH.