In Huntington’s disease, structural and functional cerebral vascular abnormalities have been shown (Vis et al., 1998; Lin et al., 2013; Rahman et al., 2013; Hua et al., 2014; Drouin-Ouellet et al., 2015; Hsiao et al., 2015; St-Amour et al., 2015) and aggregation of mutant Huntingtin is present in the neurovascular unit (Drouin-Ouellet et al., 2015), which may affect the ability of the vascular system to respond to the demands of acute exercise. This evidence concerns the gene HTT and juvenile Huntington disease.