What Your Resting Heart Rate Tells You About Your Fitness

In previous articles, we learned about the heart and how heart rate is related to fitness (if you don’t know, check out our first post in the series here). We briefly looked at maximum heart rates — or the rate that your heart beats while performing at max capacity — and briefly discussed resting heart rate — the rate that your heart beats while resting. Resting refers to any time you are not exercising or being physically active.

To measure your resting heart rate, find a quiet place to either sit or lay down. If you can turn the lights off, even better! Try to relax your body and mind by focusing on your breathing. Remain as still and relaxed as you can for five full minutes, then find your pulse. This can be done by gently palpating, or feeling, the palm side of your wrist on the thumb side. Once you’ve found your pulse, use a stopwatch to count how many times your heart beats over a 15 second period. Once those 15 seconds are up, multiply the heart beat counts by 4. This is your resting heart rate.

An average resting heart rate can range between 60-99 beats per minute. Some athletes have shown to have a resting heart rate of 30-50 beats per minute. But what does that mean exactly? It can mean a few things, including indicating the heart’s efficiency and reflecting how much blood a person has.

Through training, the heart muscles can strengthen to make each pump push out more blood with less effort. When the heart is relaxed, prior to pumping, the chamber is filled with blood, ready to eject into the body. As a person's heart gets stronger it slows the heart rate down, allowing the chamber to fill with more blood than at a higher rate. Because the conditioned heart is strong enough, it is then able to pump a larger portion of the blood to the rest of the body.

The amount of blood in an individual's body varies. Typically, it’s relative to a person’s size, because a larger person is going to need more blood than a smaller person. If someone has a higher level of blood volume, that means that they have more blood to deliver oxygen to the working tissues. More blood to deliver oxygen means that the heart doesn’t have to work quite as hard to get blood to those tissues. This results in a lower heart rate. Blood volume can be influenced by training, but will eventually hit a genetic (and size) barrier. In athletes, you’ll typically see a higher than average blood volume level. However, some athletes will utilize an illegal technique known as blood doping to improve their performance.

So what’s the significance of having a slower resting heart rate? A slower resting heart rate has been associated with a higher VO2 max, which is a measurement of the maximum amount of oxygen a person’s body can utilize while working at their maximum aerobic capacity.

A strong heart that can efficiently pump more blood to the body while exercising doesn’t need to pump as fast as a less conditioned heart, and more blood in the body means more oxygen to the tissues. Aerobic exercise has been shown to increase your maximum VO2 capacity. However, training can only do so much because of the genetic barrier.

There are a few ways to measure your VO2 max. The most efficient option involves specialized equipment and specific tests to assess your body’s efficiency. Seeing as we don’t all have access to this kind of specialized equipment, we can use a simple formula called the Uth-Sørensen-Overgaard-Pedersen estimation.

VO2max = 15.3 x HRmax/HRrest

You’ll need to find your maximum heart rate (220-age) and your resting heart rate (as discussed above). For example, 15.3 x 193 / 63 = 46.9 ml/kg/min.

Fitness levels are typically reflected in a person's resting heart rate. To improve your fitness level and potentially reduce your resting heart rate, try incorporating regular cardio workouts into your exercise routine that raise your heart rate to 40-60% of your max heart rate. After training for six weeks, reassess and see if there’s a difference! Good luck!

Maddy has worked in the health and fitness industry for 5 years. She has a bachelors in Exercise Science and has recently received her Masters in Exercise Physiology. She has worked with a wide demographic of clients as a Personal Trainer and loves helping people reach their goals and continue to grow.  She is an outdoor enthusiast and dedicates her workouts to rock climbing, hiking and whatever new experiences may come her way.

Main Photo Credit: Denys Prykhodov/shutterstock.com; Second Photo Credit: Crdjan/shutterstock.com; Third Photo Credit: Syda Productions/shutterstock.com