I've had a pretty good week, I've gotta say. I started doing the Couch to 5k running program last Tuesday, which has gotten me into the gym for at least 30 minutes of good cardio every day for the past week, and the results have been FABULOUS for my blood sugar. I've dropped my basal .05 units/hour, and I turn my pump off for at least two hours a day before exercise. My total daily dose is coming in around 17 - 23 units. I'm very happy with these results.
I'm still having problems with going low by the end of my cardio session, though, so I'm doing lots of experiments with how to combat this. Usually, I turn my basal off 2 hours beforehand and eat a piece of wheat bread with peanut butter about 30 mins before, and I end my 30-45 minute workout around 85-95. Pretty good, right?
So why would I want to mess around with that, huh? Well, sometimes I like to work out longer than 45 minutes, so now I'm working on how to find that balance. There's lots of experimentation, needless to say.
This afternoon, I tested my BG at 4 pm and it was 77. Hmm, so I turn off my basal, grab some almonds and go about my business. I get home at 6 pm and decide to have two pieces of bread rather than the usual one, just to be safe. I give the food about an hour to digest, and then I'm off to the gym for 30 minutes of running, maybe a little something extra if my BG hasn't responded well to the extra carbs. I finish my run at 138 - higher than I like. So I do 20 minutes on the bike - and finish at 145?!
So I decide to call it a night and go home. It's 8:30 at this point, and I realize that I haven't had any new insulin coursing through my body for the last 4.5 hours. Assuming everything I think I know about insulin is correct, it only has a 3-4 hour half-life in my body to begin with, and I'm thinking basal insulin has an even short active period because the amounts are so small. So from about 7:30 on, when I was doing the actual, you know, exercise, I didn't have any insulin to transport the glucose from my blood into my hungry little cells. I forgot that while exercise increases the effectiveness of insulin, it doesn't replace it entirely.
So there's my lesson for the day, exercise needs insulin as much as insulin needs exercise.
This little episode has also taught me that I need to keep my better track of my ongoing exercise/BG experiments if I have any hope of trying to learn from them.