Post-Exercise Highs and Lows

Today's workouts were great but the rest of the day was a little rocky--how easily my body reverts back to its high-in-the-morning/crash-in-the-afternoon pattern. I woke up a touch on the low side, ate some Luna Moons and started my 4000-yard swim. I decided beforehand that I would test halfway through, since I was trying out a new basal rate of 1 U/hr. After 2000 yards of warmup, some drills and long sets, my BG was 137; I ate a GU (which I also intend to do at IMCDA) and finished off with 4 sets of 500 yards. I came out of the water at 184 and was stable over the next 15 minutes. Previously my BG would start climbing immediately after I stopped. I started running about 20 minutes later, and ate 20g about 20 minutes into the run when my BG had fallen to 129. I was happy to see that this was stable through the rest of my run and for 15 minutes following the run. When I finished the run, I bolused and waited a few minutes before eating a Stinger (honey) energy bar (about 25 g), and then I bolused immediately for breakfast using my 1U:9g carb ratio (same as yesterday). As is apparent from the chart, though, the results were very different.

My workouts ended about an hour later today than yesterday, once my basal rate had already moved from 1 to 0.4 U/hr, which leads me to wonder if the high was mostly caused by the reduced basal rate following exercise. Yesterday my basal rate was still at 1 U/hr for the whole hour following exercise. But I did bolus almost 10 units immediately following the exercise. Wouldn't that be enough to substitute for a 1 U/hr basal if I didn't eat more than my recovery bar (25g) for a full hour?

I believe I was low throughout the afternoon today compared to yesterday due to the increased duration of the workouts. My basal rate was pretty low at 0.25 U/hr; still, once I can see that I am running low, I could immediately set a temporary reduction rather than slogging through lows for 5 hours.

Having stable BG's during exercise was the big victory for today and I hope that I can make some progress on the high/low problem following exercise. At least my numbers today were on the chart, and the period of high BG was only about 3 hours.