Good example of using a HRM. I couldn't seem to get my heart rate up and couldn't figure it out. I thought my legs were to weak or something.I went out to west Texas and I did terrible. What the heck is going on. Anyhow, by the time I got home I was beat. I took off about 10 days from riding and I cant believe the difference. I didn't think I was that tired, but now I can run my heart rate up pretty easy and it drops pretty fast too. If I feel like running it up to the mid 140s or just cruise in the 120s, I can do that now. Like the man said, recovery is a must.