My wakeup heart rate was 63, and that is high enough that I should have stayed home. But I went running with a hope of doing 2.5 miles. However, at 1/2 mile, I turned around and went home. My legs felt like they were made of lead, and I had no energy for walking much less for running. I took a nap and felt better. I've been seriously sleep-deprived for the past couple of weeks, and it finally got to me. I did have the last two nights of good sleep, but my body still sent me a loud message that I need to change my behavior.