OK wow. I have to drop my bike off for a tune up tonight, so I did my TrainerRoad workout at lunch (I work from home). It was 6 sweet spot intervals of 6-7 minutes. Shouldn't have been a big deal, I did a similar workout on Monday and did fine, heart rate never really going above zone 3.
A few intervals in I'm thinking this feels kind of hard. My heart rate is getting up in zone 4 and 5. Eventually I hit a few beats above my max I have ever measured my heart rate and it is steady there. I don't know if maybe I'm tired or too hot or something, or what. But I plan on gutting it out.
As I'm finishing up interval 5 of 6 I look at the screen and notice that the icon for my power meter icon is not on the screen. So TR is not connected to my power meter, it's connected to my trainer, which reports a good 10 watts under my power meter. So I've been doing some of these intervals at FTP and maybe even over FTP at times. At that point I decided to do without the last interval :P
This is actually a problem I have had with certain devices and the iPhone. Most Bluetooth devices have an icon in the settings that allows you to disconnect, but things like my power meter and heart rate monitor don't have the icon, so if the phone is somehow blocking an app from connecting to a device, the only thing that works is rebooting the phone. I'm not sure what happened here, because I did the same thing I always do, which is use the power meter app to zero it out and then switch to TR. Never had a problem before so I didn't bother to check.
Now, if my max heart rate has gone up, can that mean I am getting more fit? It wasn't just a weird spike, it was sustained at that rate for several minutes at a time.