If I asked you to predict the outcome of a sporting event in the Olympics, what would you look at in order to make your prediction?
Past success?
Markers of strength?
Markers of cardiovascular fitness?
The country the athlete(s) is from?
What if I told you that if you could look at the athletes heart rate during competition you could have a pretty good guess as to whether they are going to do well or not?
Shocked?
It seems so simple…how can that be true?
It’s actually pretty straightforward.
Heart rate is a measure of how hard your body is working. If two athletes are doing the same amount of work but one athlete is able to do it with a lower heart rate, their perceived exertion is likely less, meaning they have more to give. That athlete can likely increase their performance more than the other athlete, hence they are more likely to win. This was actually shown to be true in the 2020 Tokyo Olympics during an archery competition [1].
How does this translate to everyday folks who are not competing in the Olympics?
What if I told you that heart rate is also associated with how long you are going to live?
While lifespan is not a sport, it certainly is something that everyone cares about!
Multiple studies have shown a correlation between resting heart rate and your risk of dying of virtually any cause.
This figure above from a 2015 meta-analysis which included 46 studies on resting heart rate and all cause mortality shows that as your resting heart rate moves up from 45 beats per minute you start to see an increase in risk of death. The meta-analysis found that for every 10 beat per minute increase in resting heart rate your risk of dying increased by 9%. This 9% increase for every 10 beat per minute increase was linear until you got to about 90 beats per minute at which point the increase in death became exponential [2].
On the other hand we know the majority of the population is not so healthy, so does this risk also apply to people who are physically active, dont smoke, don’t take medications, don’t have any known medical conditions, and have a healthy diet?
The short answer is yes!
It doesn’t matter if you are doing all the “right things”, if your resting heart rate is elevated your risk of dying is going to increase. (Although as we will discuss later the chances of this being the case are very slim!)
Another study [3] adjusted for all of the usual lifestyle factors and they found a resting heart rate in the range 51–80 bpm was associated with about a 40–50% increase in risk, a resting heart rate in the range 81–90 bpm conferred a twofold increase in risk, and resting heart rates above 90 bpm risk conferred a threefold increase in risk compared to subjects in the lowest heart rate category (<50 bpm)!
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3664385/
There is another study that was done on 5,000+ men ages 42-53 over the course of 20 years and even after correcting for things like tobacco consumption, physical activity, diabetes, BMI, blood pressure, and cholesterol, an elevated resting heart rate was still associated with an increased death rate [4].
https://www.ajconline.org/article/S0002-9149(08)01585-3/fulltext
It is clear that an elevated resting heart rate can be used as a warning sign that something may be wrong but what is it really telling us?
Unfortunately we can’t look at an elevated resting heart rate and say the root cause is X. It’s really just something we can easily measure that can indicate to us that something is not right and we should probably take action. It’s equivalent to the check engine light on your car. You may still be able to drive the car but you probably want to bring it in to get checked out before something goes terribly wrong.
Our heart rate reflects the amount of stress our body is under. When we are measuring our resting heart rate we are eliminating any kind of physical stress (we are not moving) so if our heart rate is elevated it is a sure sign that there is some other kind of stress causing the elevation. For more details on how stress impacts your heart rate you can check out this blog post.
If your resting heart rate is elevated the question then becomes what is causing the stress resulting in the elevated heart rate?
There are a couple of lifestyle related conditions we can look at that have been proven to lower your resting heart rate, but since we were just talking about stress, lets start there.
Let’s take a real world scenario that everyone can relate to…
Work stress and an upcoming vacation.
Say you have a huge work deadline coming up, you have been procrastinating, and all of a sudden everyone in the office needs something from you. Stress is obviously going to be high.
Now let’s take the same situation and add one more thing into the mix. Immediately after the deadline you are going on vacation to a tropical island (or other place you find relaxing).
Which situation is going to result in more stress over the course of the weeks leading up to the deadline?
Turns out researchers looked at this exact situation, the below graph sums up the results nicely[5].
https://pubmed.ncbi.nlm.nih.gov/31694400/
The closer office workers were to vacation the lower their heart rate was throughout the day when under high stress!
Why?
The anticipation of the vacation that was right around the corner was lowering their bodies’ perceived stress even under the same workload! Remember the study about the 2022 archery event in the Olympics…the same thing applies here!
If we can lessen our chronic physiological stress we can lower our heart rate. In other words, chronic stress is going to cause our resting heart rate to be higher, so anything we can do to lower chronic stress is going to help. Here are a great set of tools you can use to help lower your overall stress load.
Next on our list of ways to improve your resting heart rate is to get good sleep. We need sleep, it’s a requirement for life, and poor sleep is pretty much associated with any disease or chronic health condition you can imagine. It is no surprise that poor sleep will result in an elevated resting heart rate.
Between 1974 and 1992 a total of 22,444 males participated in a study where scientists looked at the correlation between sleep, resting heart rate and all-cause mortality. They found that there was a stepwise interaction between sleep disturbances, elevated resting heart rate and all-cause mortality. The correlation persisted even when researchers corrected for BMI, blood pressure, smoking, and alcohol usage. Unsurprisingly researchers suspect that the cause of the increase in resting heart rate is the increase in stress from not getting proper sleep[6].
I have written extensively on the topic of sleep, so if sleep is an area of concern for you I suggest you read the following posts.
Sleep: The Cornerstone Of Your Health Foundation
Optimizing Your Sleep Environment
The Twelve Hours Before Bed Can Make Or Break Your Sleep
The next major impact on your resting heart rate is your body composition. If you are overweight or obese, chances are your resting heart rate is going to be elevated. When you look at the research around body composition and resting heart rate many interventions include both a diet and exercise protocol so it can be hard to tease out which one (or both) is causing a change in resting heart rate. One situation where people can lose weight without an exercise intervention is when someone has gastric bypass surgery.
Researchers actually looked at resting heart rate in a group of people that underwent gastric bypass surgery. Two years after the surgery, the average weight loss for the people in the study was 100 lbs. Their resting heart rate before the surgery was 73 BPM, two years later the average resting heart rate was 60 BPM[7]!
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3019138/
So how do you achieve better body composition?
Not a simple question to answer, I could probably link to countless blog posts I have written that are associated with this goal. In fact the two things we have already discussed in this post, stress management and sleep are going to play a major role in achieving optimal body composition. To that end no body composition goal will be successful in the long term unless focus on optimizing your lifestyle and health first!
If I had to pin down the steps you need to do to optimize your body composition here is what I would say:
- Get your health and lifestyle in as best position as possible before working on body composition.
- Sleep 7-8 hours a night
- Manage stress as best you can, minimize long term chronic stress
- Minimize processed foods
- Drink Enough fluids
- Eat 1g/lb of body weight (or ideal body weight) in protein per day
- Develop conscious oversight for the amount of food you consume in order to put yourself in a caloric deficit. Examples include:
- Counting calories
- Time restricted eating
- Meal prepping
- Removing processed foods from your environment
- Limiting fats or carbs
- Incorporate resistance training
The final intervention you can do to lower your resting heart rate is to exercise, in particular cardiovascular exercise. You might be saying, “But exercise is stressful, how can that help?!?!?”
True, acute exercise is stressful, and acutely it will raise your heart rate. However the temporary raising of your heart rate is in fact what is eliciting a bunch of physiological changes in your body that over time will result in a lowering of your resting heart rate.
At the 1000 foot level, what happens is your body becomes more efficient at delivering blood and oxygen to your working muscles. It does this by increasing blood volume, capillary density (more blood vessels), decreasing blood pressure, improving the strength of your heart, making your lungs stronger, and many, many more changes which are outlined in this post.
The end result?
Your heart does not need to beat as many times to deliver blood around the body, therefore, a lower resting heart rate!
What should you be doing from an exercise point of view to achieve these results?
Most everyone will benefit from improving their aerobic fitness and to do this all you need to do is do some easy aerobic exercise, also known as zone 2 cardio. If you need more information about how to implement easy aerobic exercise into your routine see this blog post in which I outline exactly how to do that.
Resting heart rate can be a very useful metric to track over time to keep an eye on overall health. It is also very easy to track. I cover exactly how to track your resting heart rate in this blog post. You probably already have everything you need to get started doing it today!
Based on the research you want to have a resting heart rate of below 70 and ideally it would probably be in the low 50s. Of course there will be fluctuations, but acute changes are nothing to be overly concerned about. This is why a consistent measurement everyday over the course of months is ideal, it gives you a nice average of what your resting heart rate is normally and also makes it easier to spot whether you are trending up, down, or staying the same.
You will also notice all the interventions I listed above are nothing special, they are not sexy, and they are things that I advocate through the content I put out on a weekly basis. They are all about eliminating ancestral mismatches and optimizing your lifestyle. At the end of the day we can likely say that in most cases an elevated resting heart rate is just an indicator that your lifestyle is out of whack and something needs to be changed. The content I put out on my newsletter is meant to help you keep things in check in a simple and actionable way. To get more help optimizing your lifestyle be sure to sign up for my newsletter using the link below!
- (2023, January 6). Evidence From Tokyo 2020 Olympic Archery Competition. Retrieved February 6, 2023, from https://journals.sagepub.com/doi/abs/10.1177/09567976221143127 ↑
- (n.d.). [PDF] Resting heart rate and all-cause and cardiovascular mortality …. Retrieved February 6, 2023, from https://www.semanticscholar.org/paper/Resting-heart-rate-and-all-cause-and-cardiovascular-Zhang-Shen/d5f7d4684a2bed51d30c76a38908983ebd173430 ↑
- (2013, April 17). Elevated resting heart rate, physical fitness and all-cause mortality: a …. Retrieved February 6, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3664385/ ↑
- (2008, November 10). Relation of Heart Rate at Rest and Long-Term (>20 Years) Death …. Retrieved February 7, 2023, from https://www.ajconline.org/article/S0002-9149(08)01585-3/fulltext ↑
- (n.d.). Do vacations alter the connection between stress and … – PubMed. Retrieved February 7, 2023, from https://pubmed.ncbi.nlm.nih.gov/31694400/ ↑
- (2001, December 20). Sleep disturbance in association with elevated pulse rate for …. Retrieved February 8, 2023, from https://onlinelibrary.wiley.com/doi/full/10.1046/j.1365-2796.2001.00913.x ↑
- (2010, October 20). Improved Heart Rate Recovery After Marked Weight Loss Induced …. Retrieved February 8, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3019138/ ↑
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