Not something I would try, or would have tried at what I suppose is his age. I will say a runner in training can get into ketosis with no need for fasting--visi

Not something I would try, or would have tried at what I suppose is his age. I will say a runner in training can get into ketosis with no need for fasting--visiting the downwind side of marathon finish chutes would probably convince you of this. I did "hit the wall" a couple of times, but my diet leading up to the race was no different from that before other races. In one case it was inadequate training. In a couple of others it was setting out at too fast a pace. Now, that is not to say that I felt good in the others--I felt awful but bearably awful.