My wakeup Heart Rate was 57 this Morning

Even though today is a rest day, I measured my wakeup heart rate to get an idea how extra sleep is affecting the heart rate. A drop of 3 points from yesterday is significant. With me, at least, wakeup heart rate is sensitive to sleep. I had 6 1/2 hours sleep last night and will take a nap this afternoon that should bring my sleep for the past 24 hours up to 7 hours.