Activity is one of our key variables and one of the most difficult to quantify. Aside from adrenaline increasing blood sugar, activity can reduce it. This is one of those things that we just have to keep an eye on and roll with it. Jonathan is a fairly active kid, he doesn't sit in one place for any great length of time other than early morning and maybe late in the evening, usually he is go, go, go. This is helpful in a way as his ratios are set up based on periods of observation and as such have some level of activity built in. A little less activity and he'll trend up and we can correct with insulin, a little more activity and he'll likely not dip too low. There are days however that are filled with running and jumping and rolling and sliding and potentially low numbers. We do reduce bolus at the meal before planned high activity levels, but sometimes it's not planned.
I've mentioned it before, but it's important to us so I'll say it again: Jonathan is a 4 1/2 year old kid first and a diabetic second and therefore play time usually trumps D fears. Sometimes this means that I have to do extra checks on extraordinary days and I have to plan for extra snacks to be available from him, but it is what it is. The surprising thing is how fast he can drop when he's more active than usual. Between breakfast and lunch or lunch and dinner he most often still has insulin from his bolus on board and that is of course playing a role but I've seen him go from 16 (288) at meal +2 hours to 6 (108) in 30 minutes and I can take a SWAG as to where he would have been in another 15.
Jonathan is at a point still where he either doesn't recognize dramatic changes in blood sugar or is not sure how to express it. Above 3 (54) he is non-symptomatic so we really have no choice but to test more often. Sometimes I feel like a human CGMS but being his dad, I do it happily and without hesitation because just as important as his health and well-being is to us, also being a kid and having every opportunity that he should have is too.