I was feeling good about my interval training on the elliptical machine. I’d been doing 4 intervals of speed-up in 12 minutes and feeling energized when I got off the machine.
Then, a week ago, I did 3 intervals and I felt tired. My thoughts went into loops. Am I catching a cold? Am I getting weak? Is something seriously bad going on with my health? After all, a few days before, I’d gotten a slipped disc in yoga. Maybe my body was in a slump. Waaaah!
I’ve worked too hard, too long, in far too many ways, to let that happen. But it was happening anyway. I felt tired. Me. After only three 30-second speed-ups.
Then I remembered something from the 70s. Biorhythms. Everybody has a cycle of bad days and good days. Here’s a website with a free calculator: http://www.facade.com/biorhythm/
Sure enough – I was at the bottom of my physical cycle.
Okay. I could expect my body to be stronger in a few days.
And PostureDoc, a channel I subscribe to on YouTube, uploaded a video about interval training: http://www.youtube.com/watch?v=aKiVaJk4eYw
He made the point that I shouldn’t do a 2nd interval until my heart rate has returned to my normal range. That isn’t necessarily 2 minutes, like I’d been doing. The elliptical machines at my gym has a 50 second delay before displaying the heart rate. So, during the speed up, my heart rate may look like it’s staying at about 116 bpm. Then a minute later, it will jump up to 148 or higher. So, it may take 3 minutes to get back to my normal range. And even then, I may still have an oxygen debt.
I noticed that after each subsequent interval, it takes a bit longer to return to my normal heart rate. But if I wait for it, I can do 4 intervals even at the bottom of my biorhythm cycle. It may take longer that 12 minutes, but what’s a few minutes when the goal is a lifetime of an active body?