Yes, I saw that and other posts that were very similar. I think something else must be going on having to do with stopping exercise, a corresponding drop in insulin, but a short term build up of the blood glucose that is now not needed. Maybe it has to do with the stress of exercise and other hormones like cortisol involved that delay the 'return to normal'.

My current self experiment is trying to not eat for an hour after exercise to monitor blood glucose and then having a protein MCT shake to keep blood glucose down while my body recovers.