I actually went to the exercise class on Saturday morning. It’s true – I ignored my excuses and exercised with a group. I also used a bunch of muscles that clearly haven’t been used in a long time, if ever. For that I am paying big time – two days later! And on Saturday I experienced the lag effect in terms of blood glucose levels.
As the link above explains, the lag effect is a situation where the stored glucose in our muscles and liver are released into the bloodstream and then burned for energy when we engage in moderate or intense exercise. This stored glucose is called “glycogen” and it can take several hours for the body to replenish it. During this time, which can last up to 24 hours, we can experience low blood glucose levels.
Exercise is a critical part of successfully managing and living with diabetes. Figuring out how to keep blood glucose levels in a safe and healthy range during exercise can be a full-time job and quite frustrating. When I exercise and then experience high blood glucose levels, I feel like all that work was a waste (even though I know it wasn’t). When I exercise and then have a low and have to chow down a bunch of extra calories, that’s pretty discouraging too. With some effort and enthusiasm, though, it is possible to make it work. A book that has been recommended to me (but I have not read yet) is called Your Diabetes Science Experiment by Ginger Vieira.
Back to the lag effect. On Saturday I took my insulin and ate breakfast (I never exercise on an empty stomach or without insulin). Those with type 1 diabetes need insulin working at all times, and we have to take it from an outside source. If we exercise without enough insulin working, we will go high. We have to be careful not to take too much insulin, or exercise will make us low.
Those with type 2 diabetes typically just see lower blood glucose levels with exercise, however, sometimes it takes a while for the blood glucose to respond. Just keep taking your medications as directed, make healthy eating choices and be consistent with exercise and you should start to see those numbers come down – especially with weight loss. If you continue to see elevated numbers despite all this effort, be sure to check in with your health care provider.
I checked my blood glucose about three-quarters of the way through the class and it was 99 (yea!!). Right after the class I was 152 (huh?) and then about 30 minutes after that I was 222 (what?!). It is likely that all that glycogen got turned into glucose and when I stopped exercising, the extra glucose was still hanging out in my bloodstream. However, muscles keep working after exercise, so we keep burning that glucose. Later that afternoon I had a low, so I probably didn’t need to take insulin to bring down the 222 (which I did). Throughout the evening my blood glucose level stayed right where I wanted to be (despite a rather large Chinese dinner). I’m chalking that one up to the lag effect. Next time I will know to take a little less insulin and eat a little less Chinese food.
As always, it’s a work in progress and a learning process. I often refer to diabetes as a “science experiment,” so I like the name of that book!