This is part two of a series on heart rate monitors. If you missed it, you can get part one here.
Two things you will learn (and when you learn them, will make your HR monitor more useful to you) are your resting HR (RHR) and your maximum heart rate (HRmax). Your RHR is pretty easy to get. You can sleep in your HR band (uncomfortable but minor if you’re a true geek). Then, with minimal movement, check your reading as you first awaken. Alternatively, you can put the HR strap on first thing in the morning (without standing up), lie there for about five minutes and then check the reading. Voi-lá, that’s your RHR.
Your RHR is a sweet way to confirm that your fitness is improving. It will actually get lower as you become more fit. That’s because your cardiovascular system gets more efficient at delivering oxygen to the muscles to fuel exertion. So your heart doesn’t have to beat as fast to support activity. (It’s grasping things like this that makes me want to go back to school for yet another degree: Exercise Physiology.)
If you watch your RHR for several days in a row and find it consistent, then you can use that information as a way to check on your overall readiness to train on any day. If you find your RHR 5-10 beats per minute (bpm) higher than normal under the same conditions (i.e.; no excess motion when taking it) that could be a sign that you’re battling an infection, or you could be training too hard and need to rest. It’s like having an advance warning system.
Now, about finding your HRmax, which is trickier and I’m going to recommend you be patient and figure this out over a little time and experience. While HRMs (and lots of other fitness equipment that use built-in HRMs) are set up to automatically calculate a maximum heart rate estimate for you based on your age, those equations can be pretty off. For example, when I use the equation to determine my HR, the resulting maximum is about 25bpm off of what I know my max heart rate to be.
The equation, such as it is: HRMax = 208 – (.7 x your age)
If you have nothing else to go on, start with the equation as an estimate, but as you wear your monitor in sustained cardio sessions you’ll be able to see if that number bears out. For example, if you’ are running in a 5K and you’re actually pushing yourself hard (not doing it as a fun run, chatting with a friend as you jog), check your monitor in the final 100 yards when you’re really gunning for the finish. Or if you’re doing a hard running or biking workout, build intensity incrementally so that on the final 5 minutes you’re either running up a hill or cycling at what feels like a 10 on a scale of 10. Compare that number to the number you get in the equation above. If they are close, you’re fine using that number. As you keep working out and wearing your HRM you may see a higher number, in which case, you can recalibrate and call that your HRmax.
HRmax is extremely variable. One very fit person could have a HRmax of 160. Another very fit person could have a HRmax of 220. The max itself is just a given, not a sign of fitness. The fact that my HR max is 200 and yours is 170 doesn’t make either of us healthier, stronger or better. It’s just like your shoe size is 7 and mine is 9. It’s what you can DO up to and at your HRmax that shows your fitness. And the cool part about that is that you can actually measure changes in your fitness by comparing what you once could do with what you now can do at any given heart rate. More on this in Part Three when we explore using heart rate zones and training.
In the meantime, keep beating.