Background: The purpose of this study is to describe feasibility and test-retest reliability of the six-minute walking distance test (6MWD) and an adapted shuttle run test (aSRT) in persons with severe intellectual and sensory (multiple) disabilities. Materials and Methods: Forty-seven persons with severe multiple disabilities, with Gross Motor Function Classification System (GMFCS) grade I and II and wearing a heart rate monitor, performed the 6MWD and the aSRT twice. Results: Ninety-six per cent of the participants completed both tests successfully. Wilcoxon signed-rank test revealed no significant differences between test and retest (P less than 0.05). Intraclass correlation coefficients for all variables were greater than or equal to 0.90. Limits of agreement for aSRT in GMFCS II subjects were insufficient. Conclusion: Six-minute walking distance test is feasible and reliable for measuring functional exercise capacity in GMFCS I and II participants with severe multiple disabilities. aSRT is feasible and reliable for measuring aerobic capacity in GMFCS I participants. Compared with others, participants with severe multiple disabilities achieved poor results in 6MWD.