When I started on my journey with diabetes, I knew that exercise was needed. That raised the question: when in the day to exercise?
The literature is a bit poor on that subject. It is often advised to type 1 diabetics to exercise before their morning meal and before injecting with insulin to reduce the risk of low sugar. Type 1 diabetics secreting no or little insulin, the regulation of glycemia needs to be done through medication only. Hypos are therefore real concern. In the morning, levels of cortisol and other hormones are higher and therefore favour higher blood sugar, so it makes sense.
In my case, because I’m type 2 diabetic, I suspect my body still regulates as much as it can the amount of insulin in my bloodstream. It just can’t cope with the cells’ resistance. So hypos are less of a risk as levels of insulin will vary naturally (though the risk exists). There is some evidence that exercising away from fasting may be better for type 2 diabetics.
I decided early on that I wanted to exercise around every meal. In part because I was very unfit and I couldn’t exercise for long periods of time. It was therefore easier to exercise several short periods during the day, than a long one in the morning or evening. In part it was also because I wanted to use exercise as a glycemia control mechanism.
The question became therefore: is it better to exercise before or after meals?
Exercising before meals has the downside of generating hunger due to falling glycemia. So you end up wanting to eat more, which is counter productive when you’re trying to lose weight.
After meal exercise doesn’t have that problem since you’re going to use the large amounts of glucose in your bloodstream your body can’t remove due to your condition. So it shouldn’t make you hungry and it should purge your system of excess glucose (or some of it at least). It also means that you’re lowering greatly the chances of a hypo due to exercise since the glucose is already there.
Therefore, the exercise plan I decided on was to walk or run 45 minutes after every meal for 10 minutes at first, 25 minutes now. That way I’d decapitate the glycemia spike after the meal, reduce the glucose in my blood my body can’t get rid of, and avoid fat storage.