https://ift.tt/3rcmhih I did a three-hour ride today, and for the majority of it, I wanted to stay at a heart rate of 120, which is a brisk aerobic pace for me. I discovered my gps watch has “alerts” you can set, one of which is a heart rate range, so I set that for 116-122, and it beeped!! at me whenever I went higher or lower. This was helpful, I didn’t have to keep glancing at the watch to spot-check my heart rate. It turns out if my level of exertion is what I call “brisk but comfortable”, it reliably keeps me in the target range. This is enjoyable and relaxing, and also a good workout. For me, I also notice it corresponds to “ventilatory threshold 1” (VT1): the “talk test” is recommended for an easy pace. If you can sing, it’s too easy. If you can have a regular conversation, it’s just right for easy pace. As your pace gets a bit brisker you just start to notice a bit of a challenge on your breathing. That’s “VT1”. On the way back I threw in some 60-second sprint intervals and so...