The technology for how we measure heart rate, at both rest and during exercise, has come a long way. Once large and cumbersome machines, heart rate monitors are now small, wearable personal devices.
So why use a heart rate monitor? Despite the technology improving, has the information gleaned really changed that much? Ultimately, we’re counting beats. Well, it’s the context around these beats that matters.
The ability to measure and monitor our heart rate throughout the day, at rest and during exercise, and the depth of data that these devices collect, is the critical factor. They might just help you to uncover some health risks that lie ahead, before they turn into serious problems.
What can we learn about our health and wellbeing, by keeping tabs on our heart rate?
Why are heart rate monitors important?
Firstly, measuring heart rate over time is important because our heart rate changes as our activity levels and our need for oxygen changes. And the new tech certainly enables us to do that.
Just taking your heart rate at a given point in the day offers some insight. Measuring heart rate throughout the day and over time however, gives a clearer picture of what our heart rate is doing at rest, and also while training at different intensities.
And the numbers we see flashing back at us can give us plenty of insight, not only into our current health, but the health risks we might face in the future.
Resting heart rate
The most straight forward measure is determining our resting heart rate.
Our resting heart rate can tell us a lot about our health. At rest, your heart is pumping the least amount of blood and oxygen that your body will need at any given point. It’s like our base level heart rate.
Best taken first thing in the morning after a good night’s sleep, if your heart rate is high at rest, this might be a cause for concern.
For most healthy adults, the average resting heart rate ranges from 60 to 100 beats per minute. Although having a resting heart rate in this range may be considered normal, you certainly want to be at the lower end in general.
Research tells us that a lower resting heart rate offers protection against a range of heart-related conditions, including heart attack.
Further to that, studies have consistently shown resting heart rate to be an effective predictor of coronary artery disease, stroke, and even non-cardiovascular diseases in the general population.
A study from 2010 found that those with a resting heart rate of more than 76 beats per minute were 26 per cent more likely to have a heart attack or die from one, than those with less than 62 beats per minute.
The study also showed that a resting heart rate above 80 beats per minute, should spell a visit to the doctor as you could be at a high risk of cardiovascular disease.
Your heart rate during exercise
While measuring your resting heart rate is important, measuring your heart rate when you’re exercising vigorously, although more complex, can also be very revealing about our health and fitness.
First we need to calculate our maximum heart rate (MHR), to understand where our heart rate sits as a percentage of that maximum, during exercise. An estimate of our MHR can be calculated by subtracting your age from 220.
Understanding our MHR and keeping tabs on our heart rate during exercise can provide information about our general fitness, our aerobic capacity and VO2 Max.
How quickly and at what intensity of exercise your heart rate reaches high levels — say, 80 per cent of your MHR — tells us about the limits of our aerobic system. If our heart rate is hitting these highs quickly, that indicates a lack of aerobic fitness, a risk factor associated with cardio-vascular disease.
Your anaerobic threshold, however, indicates the intensity of exercise where your body shifts from using aerobic energy, so oxygen-based energy, to anaerobic energy. At this point, lactic acid starts to build up in your muscles and diminishes performance.
We get a gauge on our fitness levels by understanding the heart rate that sees us reach this anaerobic threshold as we increase the intensity of our exercise. Those who are aerobically conditioned can push the limits of their aerobic system by increasing the intensity. This sees an increase in their heart rate, but they’re able to stay in the aerobic system.
Think about the marathon runner who is moving at a fast pace, but is able to keep up those speeds for the duration of the race because of the limits of their aerobic system. By keeping track of their heart rate, they’re able to determine how hard they can push before they start seeing lactic acid diminish their performance.
Those who are not in great shape will reach this point quickly. They’ll move into the anaerobic energy system at a lower heart rate, which means their aerobic system is poor and their body is not consuming oxygen effectively, and they will tire quickly.
Finally, your VO2 max is the maximum amount of oxygen your body is able to use during exercise. As you exercise, your oxygen needs increase. Your heart rate goes up as does your oxygen consumption. But there is a limit to how much oxygen your body is able to absorb and at what heart rate. These numbers determine your capacity for aerobic work.
Several large observational studies have indicated that increases in aerobic capacity and VO2 max is associated with a lower risk of cardiovascular disease, and has an inverse relationship with resting heart rate. Therefore, the greater your VO2 max and aerobic capacity, the lower your resting heart rate.
Improving our heart rate numbers
The good news is that vigorous exercise is the best way to both lower your resting heart rate and increase your maximum heart rate and aerobic capacity.
Research has shown that we can train to bring down our resting heart rate, while making our bodies more efficient at pumping blood and oxygen around the body during vigorous exercise.
Even small amounts of improvement in your aerobic fitness can lead to significant health benefits down the road.
So pick up a quality heart rate monitor, keep an eye on your heart rate at rest and during your workouts, and get to work on improving these numbers. Any reduction in beats per minute at rest will add years to your life.