How to Read Your Resting Heart Rate (And Why It Matters)

Why My Heart Rate Dropped 

This past week, I needed to get an EKG as part of an outpatient surgery pre-op protocol; I had to have a D&C hysteroscopy to remove a tiny endometrial polyp. I was SHOCKED by the results.

If you know me, you know I loathe the word “shock.” I find it melodramatic (even for me, and I love me some melodramatic moments!) and rarely appropriate or accurate. 

But in this instance, SHOCK was the letter-perfect word to describe my reaction to seeing my resting heart rate was just 52 beats per minute! 

This was a direct result of the past 5 months of my 6-month experiment with trainer Korey Rowe, and it was all I needed to realize just how effective this training and wellness program has been.

What is Resting Heart Rate—And Why Does It Matter? 

From a cardiology perspective, resting heart rate is a direct reflection of our level of fitness/conditioning—and lower is better. I’ll explain this in more detail in a bit, but for comparison: 

A resting heart rate of 60-100 bpm is considered normal; mine was 67 bpm BEFORE I started the 6-month experiment. That latest EKG result was a full 15 points lower. 

Never in my adult life have I been so fit and conditioned—including when I was 42 years old and competing in sprint-distance triathlons—that my resting heart rate was this low!

There have been many other surprises and outcomes during the past 5+ months of this experiment, which I will detail in future newsletters as I compile and review them all. 

But I felt compelled to share this immediately because it’s so significant. So, conditioning-related heart rate improvement is on the Ajenda today; here’s a mini-med school on resting heart rate and cardiac function.

What a Lower Resting Heart Rate Means 

For the most part, a lower resting heart rate is a common indicator of improved cardiovascular fitness. Specifically: 

1. Improved heart efficiency

When you do regular aerobic exercise, your heart becomes stronger and pumps more blood with each beat. This is called stroke volume increase. The equation from basic cardiology is “Cardiac Output = Heart Rate x Stroke Volume.” In other words, with improved aerobic fitness, your heart doesn’t need to beat as often to maintain adequate blood flow. That’s a good thing.

2. Increased vagal tone

Exercise boosts the activity of the parasympathetic nervous system (responsible for the “rest-and-digest” response). This boosts vagal tone, which slows the heart rate during rest by promoting relaxation.

3. Decreased sympathetic activity

Regular exercise reduces sympathetic nervous system activity at rest. This system is responsible for the “fight-or-flight” response and higher resting heart rates, so less activation leads to a calmer, slower heart rate.

4. Improved oxygen delivery

Exercise enhances the efficiency of your body’s oxygen delivery system. Better oxygen utilization in muscles reduces the heart’s workload, meaning fewer beats are needed to meet the body’s needs at rest because it pumps more oxygen-filled blood with each beat.

5. Heart remodeling

Over time, the heart adapts to regular exercise by growing slightly larger (the left ventricle specifically), which allows it to pump more blood per beat (this is the stroke volume part). This is particularly common in endurance athletes.

6. Hormonal adaptations

Fitness training leads to changes in hormone levels, such as reduced resting levels of adrenaline and cortisol. These hormones can elevate heart rate, so lower levels contribute to a slower resting heart rate and better cardiac health.

All of this emphasizes how much increasing overall fitness optimizes the cardiovascular system. It becomes more efficient and less strained, which is reflected in a lower resting heart rate. 

But here are the qualifiers, and many of my followers raised these questions after my Instagram post about this last week. Sometimes a low (lower than 60) resting heart rate signals something abnormal; it can be:

• A sign of arrhythmia (such as heart block)
• A side effect of certain medications (like beta-blockers)
• A symptom of sleep apnea, autonomic central nervous system dysfunction, hypothyroidism, electrolyte abnormalities, or certain genetic or congenital conditions
• A consequence of advanced age

Most of the time, these conditions produce other symptoms as well, and are generally not common in someone with a resting heart rate in the 50s or low 60s who works out almost daily. Also, just because your heart rate is not in the 50s does not mean you’re UNFIT if you do a lot of aerobic activity. Remember, every individual’s body will respond differently to exercise.

Here’s the bottom line: When I started my 6-month experiment, I was already in good shape, but I knew I was far from fit and maximally healthy. The beauty of a program like this is that everyone’s path will be different, and so will the change—as it should be. But it WILL be a change for the better. I never expected to see such a profound improvement in my cardiac function, but that’s even more proof of the miraculous, positive response of the human body to change and committed work.

So, your dose of honesty for today: It’s never too late to make progress…whether you’re in your 20s, your 70s, or anywhere in between and beyond!

How to Check Your Resting Heart Rate

Your resting heart rate should be taken first thing in the morning before you get out of bed. Your pulse will increase with any activity—including getting up, eating, drinking, or smoking. So to get an accurate resting heart rate, you should be completely still and calm. 

If something like an alarm startles you awake, take a moment to lie quietly for a few minutes before checking your pulse. If you can’t take your pulse when you wake: Wait 1-2 hours after consuming caffeine, exercising, or dealing with emotional stress. Then lie down or sit quietly for at least 10 minutes before taking your pulse.

To take your pulse manually: Place your index and middle fingers on your wrist below the base of the thumb or just below your jaw on the side of your neck (over the carotid artery). Apply gentle pressure until you detect a pulse. Count each heartbeat for 15 seconds then multiply by 4. Or use an app on your smartphone or wearable device like a smartwatch.