I found that exercise increased my blood glucose, and I could see over 10mmol/l if I went out and rode my bike for half an hour before the 2 hour after meals test when I'd be under 8 or even 7 pottering around the house.
It might have been due to the alarmingly bad driving around here of course, but after a couple of weeks I gave up on the idea and switched to using the trampoline in the garden in peace and quiet.