I and other Type 1's have experience with this. Type 2's are probably similar. Check blood glucose before, during and after exercise completion and correct with carbs, if necessary. Check ketones too.
"One of the most common causes of low blood glucose is too much physical activity. In fact, moderate to intense exercise may cause your blood glucose to drop for the next 24 hours following exercise. This post-exercise hypoglycemia is often referred to as the "lag effect" of exercise.
Basically, when you exercise, the body uses two sources of fuel, sugar and free fatty acids (that is, fat) to generate energy. The sugar comes from the blood, the liver and the muscles. The sugar is stored in the liver and muscle in a form called glycogen.
During the first 15 minutes of exercise, most of the sugar for fuel comes from either the blood stream or the muscle glycogen, which is converted back to sugar. After 15 minutes of exercise, however, the fuel starts to come more from the glycogen stored in the liver. After 30 minutes of exercise, the body begins to get more of its energy from the free fatty acids. As a result, exercise can deplete sugar levels and glycogen stores."
I'm talking about
hyperglycimia though not hypo. A I never have or had low blood glucose.
In some people and athletes included, ELEVATED blood sugar can happen with exercise from the adrenal/stress induced liver response of making more glucose. When this happens with less insulin response, your blood glucose stays elevated.
Regular exercise does not seem to help this somewhat rare condition, as it seems to be the cause.
I have been athletic and fit my whole life, also an upper level endurance sport competitor for 25 years.
The less demanding exercise I do, my next morning fasting glucose lowers to healthy levels of 70's-80's.
The more intense exercise I do, my next morning fasting glucose elevates to 100-105, so it was like that all night sleeping but eventually lowers to 80's-90's as the day goes on.
Above was with the same healthy meals and protein for comparison.
I'm just trying to avoid per-diabetes and keep fasting glucose lower than 90, while exercising like I've always done. Since I'm not full diabetic, my blood glucose never gets to those levels like 250 as with some people.
This is backwards, but others have noted this same observation on fitness forums. And they are puzzled.
**I have my own glucose meter, how does one measure ketones??** thanks!
Post Edited (astroman) : 3/4/2018 1:01:25 PM (GMT-7)