Have you heard of the lag effect? It’s a phenomenon where exercise causes low blood glucose levels up to several hours after the activity. We often teach people with type 1 diabetes about the lag effect. We warn people to be careful and watch for hypoglycemia (low blood glucose) even up to a day after they’ve been extra active. For instance, the first few times someone goes skiing for the season, or taking a run, or something else. The lag effect typically occurs when you’re doing something more than what you are used to.
One of the great things about New York City (I’m sure it’s true of other cities too!) is that one does a lot of walking. The part of NYC that I am currently staying in has a lot of hills (not like the “hills” in Northwestern Colorado, but hills, nonetheless). To get from A to B in NYC, you have to walk. If you take public transportation, you still have to walk to the subway station, bus stop, etc. I’ve been spending my days walking around (and up and down) the buildings of Teachers College, Columbia University. Not to mention to and from the room where I’m staying, nearby places for meals, etc. Lots of walking, and my blood glucose shows it!
I have definitely been experiencing the lag effect during this stay in NYC. I was thinking today about the lag effect and type 2 diabetes. We don’t usually teach people with type 2 about the lag effect and I think it’s because, unless they take a medication that causes low blood glucose (insulin or a sulfonylurea-containing drug), exercise is just a very good thing and we don’t worry about the lows. However, the lag effect can also be used to emphasize how good exercise is: if you have type 2 diabetes and you exercise more than your body is used to, the blood glucose lowering effects of the exercise will stay with you for several hours!
So the take-home on all this is to make exercise a regular part of your day. I’m realizing that I need to walk every day (not just four times a week), since I mostly work at home now and don’t walk city streets as a rule. In addition, be aware of the lag effect (if you take insulin or an SU drug) and watch for “late lows”. Enjoy the amazing feeling of getting/being in better shape!
What are your experiences with the lag effect?