yep me too, if I do prolonged exercise (like a day's walking) then I can often get a spike of bg in the evening when I've stopped exercising.
People who get a drop in bg several hours after exercise get it because their liver has used up all its stores of sugar, so can't do its normal dribble-dribble of sugar into your blood until it has replenished those stores. You probably have a really efficient liver with extra stores, who thinks you want lots of glucose ...