Obviously weight loss and exercise is good for diabetics. No question or debate about that, but that’s more of a long-range view.
The short-range view is where I have a question though: We were talking about my buddy’s dad and got to arguing: if an individual has high blood sugar, will exercise lower his/her blood sugar right away to any significant degree? My friend argues “Yes” while I’m not so sure. In other words, if someone tests for a blood sugar of (say) 200 (to pick a round number) and then does 30 minutes of brisk exercise then tests themselves again, will their blood sugar test a lot lower than it would have had they just spent that 30 minutes sitting down?
This is for $5.00 (and will not be used as medical advice) so cites are appreciated.
The effect of exercise when a person has a high sugar level is not quite as predictable as it is for somebody with minimally elevated, normal, or even low sugar. In the latter situations, exercise will almost always lower the sugar.
In fact, the effect of exercise on sugar levels when the blood sugar is already high depends on the insulin level. If the insulin level is “very low”, then exercise will lead to an increase in the sugar. If the insulin levels aren’t “very low”, then exercise will lead to a decrease in blood sugar. In the case of type II diabetics, insulin levels are seldom “very” low. So, if a person with type II diabetes exercises, his blood sugar will almost certainly drop.
Your question really only applies to type I diabetics where insulin levels can be very low, essentially zero. If a type I diabetic has a high blood sugar and then exercises, his sugar level will fall so long as he/she has “some” insulin on board. On the other hand, if the insulin levels are low, then exercise will raise the blood sugar level. As an example, in a type I individual with a sugar of 300, it is quite possible that the insulin levels are very low, but it is also possible that they’re not if for example the person just took an insulin injection or is resistant to insulin (yes, even type I’s can be resistant).
I would need to look up what value (or range) of insulin level represents the threshold for having blood sugar climb with exercise. I used to know it, but I grow old, I grow old, I shall wear my trousers rolled . . .
To be complete, I should have mentioned that the intensity of the exercise can play a role in determining whether the blood glucose falls or rises. Exercise “intensity” determines to what extent adrenalin and noradrenalin levels will rise as a result of that exercise. Very intense exercise can lead to very high levels of adrenalin and noradrenalin. Such a response would tend to cause the blood sugar to go up.
This can occur even in non-diabetics presumably because adrenalin and noradrenalin can turn off insulin secretion if their levels go high enough. And, as you know, those substances also have a direct effect on the liver to cause it to produce sugar. Their effect on muscle is to cause muscle cells to be unable to take up sugar from the blood stream. Both changes would promote a rise in sugar levels, of course.
Type 2 diabetic here. When I exercise . . . *any *kind of sustained exercise . . . my blood sugar drops almost immediately. With simple exercise like walking or doing yard work, this is fine. But if I’m actually “working out,” I have to be very aware of certain signs that I’m working a little too hard, and either slow down or take a rest. For me, the first sign is that my hands start to get cold. I have experimented with actually testing my blood while working out, and by the time my hands get cold my reading is around 80 or 90 . . . not alarmingly low yet, but definitely on its way down. By the time I’m feeling cold and clammy and light-headed, the numbers are dangerously low, and it’s time to start eating a few glucose tablets. In time I have learned that the cold-hand level is about as far down as I should go. I have also discovered that the blood sugar lowering effect of exercise can last as long as 24 to 36 hours.
