Using interpretive phenomenological analysis, this study examined perceptions and experiences of physical activity (PA) and exercise during and following the COVID-19 pandemic among individuals with mild-to-moderate multiple sclerosis (MS) or Parkinson’s disease (PD) in Canada. Eleven participants (4 males, 7 females; 4 people with MS and 7 with PD) each completed two interviews online between May and July of 2022. Interview 1 focused on PA and exercise behaviours across the pandemic while interview 2 discussed perceived outcomes of PA and exercise changes related to physical health/functioning, psychological/emotional health, social functioning, and overall well-being. Two themes were generated using reflexive thematic analysis: 1) “It truly was a COVID-19 bubble:” The influence of isolation and restrictions in Canada; and 2) Managing MS or PD during COVID-19: “Exercising was essential.” For most participants, PA declined due to COVID-19 restrictions, which in turn was associated with an increase in symptoms. Three participants described little change to their frequency of PA, although often the mode changed and intensity decreased. Two participants described how COVID-19 restrictions lifted exercise barriers, leading to more frequent PA during lockdowns specifically. Participants also described how COVID-19 and its restrictions impacted their daily routines and psychological motivation. Findings highlight the need to provide accessible, motivating, and sociable exercise for individuals with MS or PD in situations where in-person exercise is not feasible. In particular, developing technology to allow for exercise closer to in-person experiences, aiming to increase stamina, full-body movement, and balance.