Last year for my birthday, my husband got me a heart rate monitor/watch, which I promptly returned to the store and exchanged for something else. At the time, almost a year ago, I was running very lightly, only twice a week, and the idea of wearing/monitoring/caring about my heart rate had no appeal to me.
Fast forward to less than a year later, and I’m running 5 times a week, 55KM/34M weekly average, and interested in anything that has the potential of helping me train better and stay healthy.
I’ve been curious about understanding heart rate, the concept of training by heart rate zones, improving my performance and my speed by better understanding the way my body works.
When I got a GPS watch a couple of months ago (glad I returned that original watch though, it didn’t have GPS), I decided to buy the heart rate monitor as well. Even though I knew I wouldn’t be using it regularly, it made sense to have it.
I did an experiment the last couple of days, in which I wore the heart rate monitor and watch for about 30 hours, to see where my heart rate stands at different times of day doing different levels of activity.
Some basic information about heart rate first.
Our heart rate, or pulse, is the number of times our heart beats per minute (BPM).
Resting heart rate:
Resting heart rate is the rate at which our heart beats when we are at a complete state of rest.
A normal resting heart rate for adults is between 60-100 BPM, however this number can go down significantly for athletes, possibly as low as 40 BPM. This is because regular aerobic exercise makes our heart stronger and more efficient, meaning that our heart pumps more blood each time it contracts, needing fewer beats per minute to do its job.
Maximum Heart Rate:
The maximum rate at which our heart can beat per minute at a given age.
General formulas to calculate your maximum heart rate:
Forget the old 220 minus your age. Some newer versions: 208 – (0.7 x Your Age), or another one: women: 210 – 1/2 your age – 5% of body weight in pounds, men: 210 – 1/2 your age – 5% of body weight in pounds + 4.
It’s important to keep in mind that same as with resting heart rate, the heart rate experienced under physical exertion also gets lower through regular exercise. So even though maximum heart rate would be similar for people of the same age , it would take athletes longer/harder effort to reach their maximum heart rate than for someone who doesn’t exercise regularly.
Wearing the monitor for the last day was easy and comfortable. I hardly noticed I had it on for the first few hours wearing it, later during the day I became aware that I had it on, but it wasn’t an uncomfortable feeling.
The most interesting finding was the difference in my heart rate measured at the same time (for a period of 6 hours) on 2 different days.
Both days I started wearing the monitor at around 8:00 AM, and I did the same things during the time period I wore the monitor: took the kids to daycare, drove to work, and worked at my desk job.
The only difference was what took place before putting on the monitor in the morning, one day was a rest day, the other day was after a hard effort running HIIT session.
The first morning (rest day) wearing the monitor I averaged 50 BPM, the second morning wearing the monitor (does not include exercise time) I averaged 57 BMP.
AFTER HIIT MORNING:
According to the Journal of Exercise Physiology, the heart rate of a typical individual will return to resting levels an hour after light or moderate exercise, four hours after a lengthy workout and up to 24 hours after a very intense workout session. These times will be less for athletes.
So it makes sense that even after wearing the heart rate monitor for 6 hours after finishing my workout, my heart rate was still higher than the day before.
My heart rate during my HIIT run this morning.
It went up consistently during warm up, and look at those little bumps, each one represents the fast part of the intervals, 6 total, approx. 3 minutes each.
Training Heart Rate zones:
A heart rate zone is a range of a particular percentage of your maximum heart rate. Each zone serves a different purpose for your training.