Dr Ahlskog with a quick review of the studies which looked at the benefit of aerobic exercise for PWP (2018)
youtube.com/watch?v=1xFybA9...
Note, he ends with the most significant point. You need to take C/L such that you can move well and thus be able to exercise!
The complete paper:
Aerobic Exercise: Evidence for a Direct Brain Effect to Slow Parkinson Disease Progression
mayoclinicproceedings.org/a...
"Abstract - No medications are proven to slow the progression of Parkinson disease (PD). Of special concern with longer-standing PD is cognitive decline, as well as motor symptoms unresponsive to dopamine replacement therapy. Not fully recognized is the substantial accumulating evidence that long-term aerobic exercise may attenuate PD progression. Randomized controlled trial proof will not be forthcoming due to many complicating methodological factors. However, extensive and diverse avenues of scientific investigation converge to argue that aerobic exercise and cardiovascular fitness directly influence cerebral mechanisms mediating PD progression. To objectively assess the evidence for a PD exercise benefit, a comprehensive PubMed literature search was conducted, with an unbiased focus on exercise influences on parkinsonism, cognition, brain structure, and brain function. This aggregate literature provides a compelling argument for regular aerobic-type exercise and cardiovascular fitness attenuating PD progression."