I can post studies, if really needed, but I think it's a well known fact that exercise can lead to improved oxygen consumption in everyone, so why would it be surprising that it does so with PWP? I'm not sure how these studies would at all relate to any hypotheses regarding B1 consumption or oxygen deprivation being a cause of PD. In fact, neither study showed a relationship between increased oxygen consumption and improvement with PD symptoms.

In the Schulman et al study, only the lower intensity exercise had impact on gait speed, while it had no impact on oxygen consumption. High impact exercise increased oxygen consumption but did not effect walking gait speed.

In the Uc Ey et al study, exercise increased all measured components of PD motor scores. However, increased maximum oxygen consumption correlated only with improvements on the flanker task and quality of life score with no relationship with the PD motor scores.

From my point of view, I have no doubt that exercise of all types are beneficial to PWP, although there are probably qualitative differences between the types of exercise. With regard to the other theories relating to the cause of PD, who knows. So many relationships, correlations, have been found over the past years. Some are supportive, many are not. I think soccertese's comment about smokers is very relevant. How do you incorporate that known, negative, relationship into the theories? Is there a beneficial aspect of nicotine that is somehow overcoming the lowering of oxygen consumption caused by smoking?