I respect your opinions FastingGuru, and it is clear that we have a difference of opinion in some respects, such as the use of enemas and so on, so best to leave it at that.
I base my views on muscle wastage which occurs more quickly when exercising during the fast on the research work of Dr Joel Fuhrman MD and a few others.
While eating we replenish the amino acids needed for health and repair, but when we are fasting, these amino acids are not replaced but depleted from existing reserves. So when resting while fasting the amino acids are conserved: this is known as "protein-sparing", as are the other nutrients of the body. This occurs in an effort by the body to prevent the ultimate onset of starvation; an evolutionary adaptation to preserve life.
Exercise will therefore dissipate and use-up these reserves more quickly than in a state of rest.
I am not saying you should not exercise while fasting, but what I am saying is that those suffering from disease or illness will recover more quickly and overcome their malady in a state of rest because food reserves are preserved to the maximum extent possible.
Why do you suppose that the metabolic rate is significantly lowered during a fast? an effort to preserve food reserves, and why resting much of the time will maintain this state, whilst exercise will increase it.
Nature has a wonderful way of telling us what our bodys need if we but listen to it very carefully.
I think you will find that the best method to keep young, healthy and active into old age, is via "calorie-restriction" on simple wholefoods, and as Luigi Cornaro could have told us before he died at the age of 102 or thereabouts.