BS And Exercise

[gobbly2100]

I want to find out how a high blood sugar does not really come down when you exercise apparently and I find this really not cool.

What is with your blood sugars in relation to exercise?

[jen_slc]

Diabetes and exercise can be a complicated balancing act...

In general, exercise will typically lower your blood sugar, but, as you said, only up to a certain point. Somewhere in the low 200s is where this threshold is. If you exercise at a level around there or higher, you will likely just make your BG go up, and we all know that doesn't feel good and can be dangerous.

The reason it goes up is because if your BG is 250 to begin with, you've got low levels of insulin in your body. Low insulin levels can trigger the release of stress hormones, and one of the effects of stress hormones is to increase BG. Exercise can also trigger the release of stress hormones, so you pretty much end up with a double hit of the stress hormones and therefore an increased BG level.

When your BG is somewhere around 180, a little on the high side, but still ok to exercise, you can probably bring those levels down. Which means you must have had a level of insulin in your body that was a bit on the low side (otherwise why were you 180 to begin with?), but at the same time, the level of insulin was probably just enough to combat the BG-raising effect of the stress hormones triggered by the exercise.

Why is this threshold set at somewhere in the low 200s? Who knows, that's stumped me for years. I guess that's just the point where the body says 'I can't cope with the combo of low insulin levels plus exercise- and stress hormone-induced BG rise, you need to give me extra insulin to bring this under control before exercise will help.'

To make it even more interesting, some people start off with a perfect level, say 100, and end up at 280 by the time they're done exercising, again, probably due to stress hormones (with intense activity) and the type of exercise (anaerobic).

[BlueSky]

Insulin is the key, as far as I am concerned. My experience has been that exercise always brings blood sugar down, as long as there is enough circulating insulin. And exercise never increases blood sugar in the presence of adequate circulating insulin. To the extent that you are using glucose in the bloodstream to fuel exercise, your insulin requirements go up. And not supplying it starts a chain reaction that increases you blood sugar.

[poodlebone]

Insulin is the key, as far as I am concerned. My experience has been that exercise always brings blood sugar down, as long as there is enough circulating insulin. And exercise never increases blood sugar in the presence of adequate circulating insulin. To the extent that you are using glucose in the bloodstream to fuel exercise, your insulin requirements go up. And not supplying it starts a chain reaction that increases you blood sugar.

The same is true for me. When I've had really high BGs, I've bolused insulin and gone for a brisk walk. I once went from over 300 to the 70's after a quick 35 minute walk. I would much rather go out for a walk and get the BG down quicker than just sit around waiting. If I do just sit around, that inactivity can cause my BG to go even higher before it starts to come down, which can take hours and might need a second correction.

I always, as long as it's not the middle of the night, go for a walk to help bring my BG down.

[Cyborg]

Generally, aerobic exercise lowers bg while anaerobic exercise tends to increase bg.

[gobbly2100]

Is anaerobic exercise things like weight lifting and such?

[LancetChick]

Generally, aerobic exercise lowers bg while anaerobic exercise tends to increase bg.

Yeah, that's pretty much true for me, but when the two exercises are mixed, it's hard to predict what will happen, so I always test and make sure I have gummy worms and insulin. Overall, though, exercise has a lowering effect on my basal metabolism.

[RemJet]

you should also note that, insulin isn't as effective during exercise. This is because the body's main goal during exercise is to maintain blood-glucose levels during higher metabolic demand to make sure there is a ready fuel supply for all parts of the body. Now im not entirely sure on the differences between diabetic and non-diabetic (as again, it is usually pancreatic secretion which is slowed during exercise so taking exogenous insulin probably negates this factor) but there are other factors, such as what was mentioned above, hormones, like cortisol, Human Growth Hormone, Epinepherine, Norepinepherine, which are elevated during exercise which do make it more difficult for blood glucose to be absorbed by the cells of the body for work (again to help maintain a steady supply of glucose for the entire body (brain, etc.). Also the release of Glucagon is stimulated during exercise, further elevating blood glucose levels.

Another interesting note is that the more trained an individual is (I.E. how fit they are) will have an impact on the release of these hormones. The more fit someone is the less these hormones are released during exercise. (the body becomes more sensitive to these hormones so less has to be released). which might also mean for the diabetic less of an irratic blood glucose level, during and post exercise. Just my hypothesis on this one but it is probably not right lol

Stay Fit Everyone!
Hope that made some sense lol :D

[RemJet]

Gobbly, yes anaerobic exercise is usually resistance training. It just means the body doesnt require oxygen to create energy for the working muscle. (usually intense work up to about 2 minutes is dominated by your anaerobic systems, your Creatine Phosphate System and Glycolysis) so for things like sprinting 100m, or a 90 second set of some sort of weight lifting would be mainly powered by these systems. Although of course the aerobic system is working to some extent as well. When intensity drops and duration increases this is when the aerobic system dominates.

[rocky]

If I work out with my BG above 15 it will go up during the activity, but anything lower than that it brings my BG down.

[Just_Plain_John]

Is anaerobic exercise things like weight lifting and such?

Anaerobic is exercise at an intensity that you cannot sustain continuously - you are working without enough oxygen to keep it up for very long. Sprinting or very intense weightlifting are usually anaerobic.

However, I always have a reduction in BG from normal weightlifting routines. I work muscles in sets of 8-10 repetitions, usually 3-4 sets until I get "the wobbles" indicating secondary exhaustion. (I prefer not to go to full/tertiary exhaustion and eat the barbells :D ).

Even with a brief pause between sets or exercises for a stretch, I still get a very predictable BG drop. I generally start workouts at 190-220 and burn down about 100pts during a 1/2 hour of weights or VERY fast walking.

Having circulating insulin is key (I like exercise +1hr after a meal).