I had the same but found that some short period of exercise would bring it down. I'm not talking about fitness training or exercise to lose weight, but to exercise to aid digestion. Typically people used to go for a short walk after a meal. Various hormones and ezymes are triggered which improve the insulin sensitivity. It also works the other way around. If you have a meal and then go and sleep it off, rather than walk it off, your BGs are even higher. A lot of talk is about things like cardio vascular exercises, to improve your heart and lungs, but this is quite different. I use a rower but its rather like walking up a moderately steep hill or going up a few flights of stairs. Only 5 or 6 mins. I'd guess, but that's all it is, if you were walking on the flat, it would be like a 15 min walk. It just seems to gee up your insulin response and get it to work a bit quicker.