Different Sports; Different Impacts on Blood Sugars

Blood sugars can be interesting.  Some days they like to act nice, while others it is like trying to tame a wild beast.  I'd consider myself more active than 99% of the population...maybe 99.5% of the population. 

For most healthy adults, the Department of Health and Human Services recommends these exercise guidelines:

• Aerobic activity. Get at least 150 minutes a week of moderate aerobic activity or 75 minutes a week of vigorous aerobic activity. You also can do a combination of moderate and vigorous activity. The guidelines suggest that you spread out this exercise during the course of a week.
• This averages out to 21 minutes a day of moderate aerobic activity or 10.5 minutes of vigorous aerobic activity a day.
• Strength training. Do strength training exercises at least twice a week. No specific amount of time for each strength training session is included in the guidelines.

This article, in Time magazine, says:

We exercise close to the recommended 20 minutes a day—but that's because 17% of us exercise for well over an hour, while the rest of us scarcely stir at all.

Which means that I make up for a lot of people who do nothing everyday. 

To get to the point...

I've been exercising a lot in the past few months.  This week I did an intentional cut-back week following my half marathon and all the miles I've logged this year so far.  I only ran 18 miles,  and my legs are thanking me.  However, today I did some biking.  It was nice to get outside on my bike.  I feel like I've neglected it since the duathlon. 

I've noticed that when I run, my blood sugars tend to go low during my training runs, starting at the 1 mile mark, if I don't eat something before or reduce the basal or both.  After I'm done, they'll be high and need extra insulin.  I'll go high without eating anything, even if I was lower beforehand.  I feel like this should not happen, although it typically does.

Now, biking is another story.  While riding, my blood sugar tends to be okay.  I'll occasionally snack on something, but the real issues come later on in the day, 6+ hours after I'm done.  I'll have low blood sugars the rest of the day after biking, especially if I bike more than 15 miles.  It is the exact opposite of running. 

Others sports have their quirks as well.  Volleyball tends to make my blood sugar go high, as well as basketball.  Golf has the same impact as biking, with lower blood sugars later in the day, while ultimate frisbee sends them through the roof.  Walking has no effect on them at all. 

It all amazes me.  The human body is an interesting thing, that I'll probably never be able to figure out. 

Do different sports impact your blood sugars differently?