Do Exercise And Swimming Help In Maintaining Diabetic Levels?

good morning doctor, i am male 46 year old having fasting blood sugar since 10 years 130-140 and pp 140-170 and i ma taking metformin 1000mg c/r at night after food with advise of my doctor , my concern is that, is i am diabetic or is it required to continue the medication , i am doing enough exercises ,swimming, jogging in moderately. thank and regards. faslu.