Heart Rates And Such

I'm not sure if the sudden drop in temperature (due to a fast-moving cold front) was to blame, but my heart rate yesterday was suspiciously lower than it has been in more than a week. I assume the heat wave caused an elevation of my normal rates.

They say the first sign of over-training is a depressed heart rate, a heart rate unresponsive to hard work. I would worry, except I felt super strong yesterday and knocked out my hill repeats with enough energy left over to practice my sprinting form (in an easy gear to perfect my technique).

Today I have another long endurance ride to do. You can be sure that I'll keep a close eye on my heart rate and my breathing to catch any possible signs that I've been riding too hard. I wouldn't mind a couple days off if that's necessary, but I'd like to avoid it and take advantage of this apparent good form I'm enjoying.