stamina and rest vs. looks and muscle built

I feel one needs at least as much time re-feeding, as the previous intense fast/fasts.
I believe you need to give your body chances to rebuild essential tissues and to continuously deal with your main health-goal while re-feeding. Gym may take away energy and resources from the unfinished healing.
As to how long to hold back on intense gym - can't tell. I guess it depends on the goal. I knew a girl with very malignant breast cancer, who made it go away through series of fasts - the skin ulcers from the cancer and the edema disappeared. Then she dropped all fasting, stopped being raw, return to old habits and started training for marathon. The cancer was back in few years - sad story.
Similar is the story of Terry Fox. His heavy routines made the cancer come back.
I believe the latest medical studies show that 40 min 3x a week, health-wise, is a reasonable limit for intense physical activity. There seemed to be even a disadvantage for heavily training people in comparison to couch-potatoes when health outcomes are concerned. This is physiologically best explained by the enormous (and uncompensated) oxidative stress (i.e. damage) from heavy exercise.
I know your case is not worrisome, but I feel we ought to learn form extreme examples and not repeat the mistakes of others.
I'd say devise wise and go slow :) Always recuperate and rest enough. Looks are less important than health and stamina.
Here is somth from Chrisb on this topic:
//www.curezone.org/forums/am.asp?i=2135912