Kate Cornell was diagnosed with type 2 diabetes in June of 2005. Since then, she has controlled diabetes through dietary changes, exercise, and, more recently, metformin. She shares her experiences and lessons learned here and on her blog, kates-sweet-success.blogspot.com, which was named as one of the top diabetes blogs for 2015 by Healthline.com.

Exercise is good for you…except when it’s not. People who live with diabetes will always benefit from adding exercise to their day, but if you’re dealing with certain complications from diabetes, it’s important to pay attention to some basic facts about exercise.

An ​article at Joslin.org outlines the certain types of exercise you should avoid with which complications.

Proliferative diabetic retinopathy (PDR). This complication of the eyes can lead to blindness if left untreated. You should be having a dilated eye exam yearly to ensure healthy eyes. Those with PDR should avoid strenuous lifting exercises, high impact exercises, or anything that has your head below your heart for extended periods of time.

Diabetic peripheral neuropathy. Nerve damage caused by uncontrolled, high blood sugars can lead to neuropathy, which causes pain and numbness in the extremities. Controlling your blood sugar as tightly as possible as well as exercising can help stave off this complication. If you are dealing with neuropathy, “Limit your choice of exercise to low impact or non-weight bearing activities,” says Michael See, MS, RCEP, Clinical Exercise Physiologist at Joslin Diabetes Center.

Advanced kidney disease. Those people who are dealing with advanced kidney disease can still exercise, but activities should be moderate in intensity and never strenuous.

High blood glucose levels. We’ve all experienced higher blood glucose levels, but it’s difficult to know whether or not you should exercise at that time. Here's the rule of thumb to follow:

Type 1 diabetes: Avoid exercising if your blood glucose is higher than 250 mg/dl and ketones are present. Anything over 300 mg/dl without ketones and you shouldn’t exercise.

Type 2 diabetes: Do not exercise if your blood glucose is higher than 400 mg/dl.

Exercise is always a good idea as long as you follow the guidelines above. As always, consult your healthcare provider before beginning any new exercise program.

To learn more on this topic:

Exercise Habits to Ditch
How Morning Exercise Benefits Diabetes
Exercise Tips & Guidelines for Diabetics