Yesterday, instead of taking my extended bolus on the ride, I decided to follow Matt's advice to set a basal rate that we thought would cover me for about 250 calories per hour. Matt suggested 0.55 U/hr, which is 0.1 U/hr higher than my normal basal rate at that time. Honestly I was a bit afraid that I would be high the whole time, but that was not the case. I was very happy with the outcome, and felt more comfortable that I could eat and keep my blood sugar high enough, as opposed to last week's ride. Above is a screenshot from the day using Kevin's logbook. (Thanks, Kevin!) I felt strong at the end and my only problem during the ride was some discomfort due to the heat. It was probably about 20 degrees hotter than it's been lately. I think the BG's would have been steadier if we hadn't taken such long breaks. I didn't experience a post-exercise rebound like I often do, and felt like I was absorbing more carb's following exercise without bolusing as much or at all. This may be in part due to the fact that doing workouts this long is still somewhat new for me this season; we'll see how it goes as the season continues. My insulin to carb ratio for the rest of the day was somewhere around 1U:20-40g.
As a fun note, I set my new max speed on the bike: 47.4 MPH. I think I was going downhill with a slight tailwind (the only tailwind we had for the entire ride).