Do you have Type 1 or 2 diabetes? Do you have any known complications (i.e. neuropathy, sores, etc.) or conditions (i.e. heart disease)?
Here are a couple of links to very general guidelines:
http://www.diabetes.ca/diabetes-and-you/healthy-guidelines/physical-activity-and-exercise/
http://www.diabetes.org/food-and-fitness/fitness/fitness-management/be-active-but-how.html
Contraindications are often related to co-morbidities such as heart disease, osteoporosis, pulmonary diseases, neuropathies, etc. Specific to diabetes, exercise is contraindicated under these circumstances (out of ACSM's Exercise Management for Persons With Chronic Diseases and Disabities text:
- Active retinal hemorrhage is present, or the person has received recent therapy for retinopathy (e.g. laser treatment)
- Illness or infection is present
- Blood glucose is above 250 mg/dl (14.0 mmol/L) and ketones are present (blood glucose should be lowered before intitiation of exercise).
- Blood glucose is less than 70 mg/dl (4.0 mmol/L)- because the risk of hypoglycemia (low blood sugar) is great (if pre- or post-exercise blood glucose is less than 100 mg/dl (5.5 mmol/L), carbohydrate should be eaten and blood glucose allowed to increase before initiation of exercise).
Exercise precautions are as follows:
- During exercise, a source of carbohydrate (that does not also contain fat) should be readily available
- Consuming adequate fluids before, during, and after exercise
- Practicing good foot care by wearing proper shoes and cotton socks, and inspecting feet after exercise
- Carrying medical identification
It's very important to measure your blood glucose levels right before AND right after exercise, so that you know how that exercise session affected you. It's also very important to have clearance to exercise from your doctor, and that you communicate with him/her on a regular basis about blood sugar levels and the possible need for medication adjustments as you get into regular exercise.