Why Is My Resting Heart Rate So High?

We give you the nine most common causes.

Heart rate during exercise can provide an indication of your aerobic fitness as well as the intensity level of a workout.

For these reasons, wearing a heart rate monitor or using a GPS watch with wrist-based heart rate monitoring has become increasingly popular among recreational and competitive runners. 

While capturing your exercise heart rate data can certainly be a useful metric to gauge your fitness progress and the effectiveness of your workouts, it can also be beneficial to monitor your resting heart rate.

With the advent of fitness trackers that can easily quantify biometrics like heart rate 24 hours a day and sync the data to your phone, many runners are already recording their daily resting heart rate even if they’re not regularly reviewing the data.

Looking at that data, some may wonder: why is my resting heart rate so high?

Various factors, such as genetics, climate conditions, stress levels, lifestyle changes, and health conditions and heart health, may influence your resting heart rate.

In this guide, we will discuss the significance of your resting heart rate, detail the factors that affect it, and discuss normal resting heart rate values for adults. All of this is to answer your question: why is my resting heart rate so high?

A person looking at their heart rate monitor wondering, why is my resting heart rate so high?

What Is My Resting Heart Rate?

Your resting heart rate refers to the number of times your heart beats in a minute (BPM) when you are at rest. 

When lying down and in a calm and relaxed state, your muscles and other tissues require significantly less blood and oxygen than when exercising. Therefore, your heart does not need to pump as much blood, so your heart rate is lower than when you are up and about.

According to the American Heart Association,1Ivy, J. L., Miller, W., Dover, V., Goodyear, L. G., Sherman, W. M., Farrell, S., & Williams, H. (1983). Endurance improved by ingestion of a glucose polymer supplement. Medicine and Science in Sports and Exercise15(6), 466–471. https://pubmed.ncbi.nlm.nih.gov/6361440/ the normal resting heart rate range for adults is typically between 60 and 100 beats per minute, though it tends to be lower in runners and other endurance athletes due to physiological adaptations from consistent training. 

Research suggests2Nauman, J., Janszky, I., Vatten, L. J., & Wisløff, U. (2011). Temporal Changes in Resting Heart Rate and Deaths From Ischemic Heart Disease. JAMA306(23), 2579–2587. https://doi.org/10.1001/jama.2011.1826 that a higher resting heart rate is associated with an increased risk of adverse heart conditions and heart problems such as heart failure and all-cause mortality. 

If you ever experience chest pain, seek medical assistance.

A person on a beach adjusting their heart rate monitor.

How Do You Measure Your Resting Heart Rate?

You can use a couple of methods to measure your resting heart rate. 

Heart Rate Monitors

On the technology side, you can use a chest strap heart rate monitor or a wrist-based heart rate monitor to measure your resting heart rate.

Chest strap heart rate monitors use electrodes to detect the electrical conductivity signals of your heart as it contracts (beats) to pump blood. 

Much like the electrodes used on an electrocardiogram (ECG), the electrodes of chest HR monitors sense the spike on the ECG (called the QRS complex) when the left ventricle contracts and pumps blood out of the heart through the aorta into circulation. 

In contrast, wrist-based heart rate monitors use optical heart rate sensing in a process known as photoplethysmography (PPG) to detect your heart rate. 

PPG uses flickering light (usually green LED) and special light-sensitive diodes to measure your heart rate. 

The LED light penetrates your skin and reflects off your blood. The degree to which your blood absorbs or reflects light varies according to whether your heart is contracting (beating) or relaxing between beats.

The light-sending diode registers these two variations in light absorption, integrates the data in the device with an accelerometer (which measures movement), and feeds the data through an algorithm to yield a heart rate value based on the number of times these fluctuations occur per minute. 

Two people measuring their heart rate.

Manual Pulse Detection

You can also manually measure your resting heart rate by palpating your pulse and counting the number of times you feel your pulse with your index and middle fingers.

The most common sites to measure your pulse are on the inner surface of your wrist and your carotid artery on the side of your neck.

You can also put your hand over your heart, though this can be difficult if you have significant breast tissue or muscle mass overlying your chest.

Although you can count the number of beats in a 15-second interval and then multiply your answer by four to get the number of beats per minute, it is more accurate to continue counting for the entire minute. 

This differs somewhat from the recommendations for measuring your heart rate during and after exercise, especially if trying to measure a maximum heart rate reading. Your heart rate during vigorous physical activity is more sensitive to changes in intensity level. 

Therefore, if you stop exercising or end a hard interval and want to capture your pulse at that high rate, it makes more sense to count the number of beats you feel at your pulse site over a short interval (like 15 seconds) and then extrapolate that number to a full minute rather than actually count for a full minute while you rest. 

A person with two fingers on their wrist, measuring their heart rate.

This is because your heart rate will continue to slow that entire minute, skewing your estimation of how high it was while you were still pushing your body.

In contrast, your resting heart rate should be relatively stable. Measuring it for the entire minute is more accurate because a 15-second data capture can overestimate or underestimate depending on where in your heart cycle you start and end the time.

Regardless of the measurement method, you can improve the accuracy of your resting heart rate by measuring it first thing in the morning, at the same time every day, before getting out of bed.

Taking your pulse rate readings at this time will help ensure you capture the truly relaxed state before elevating your heart rate as you move around, allowing your measurements to be conducted more consistently.

It’s particularly important to measure your resting heart rate before exercising, smoking a cigarette, or drinking coffee or tea. Nicotine and caffeine are both stimulants that can increase your heart rate. 

A person on a beach measuring their heart rate.

What Factors Could Be Contributing To My Elevated Resting Heart Rate?

So, if you are wondering why is my resting heart rate so high, there are several factors that can affect it. Some of these factors may affect your resting heart rate relative to someone else’s, while others can affect your resting heart rate from day to day. 

The primary factors that affect resting heart rate include the following:

#1: Genetics

Your genetic makeup can influence your resting heart rate. Two people of the same age and health status can have a difference of up to 20 beats per minute in their resting heart rate due to genetic differences.

#2: Age

In general, resting heart rate decreases after infancy through childhood such that toddlers and younger children have a higher resting heart rate than older children, teens, and adolescents.

Resting heart rate tends to stabilize after maturity and remain relatively constant until age 40 or so, after which point it trends upward with aging. 

A person with their head in one of their hands, stressed out.

#3: Smoking Habits

If you are wondering to yourself, why is my resting heart rate so high, and you smoke, you may have your culprit.

Evidence suggests that people who smoke regularly usually have a higher resting heart rate than non-smokers. Nicotine is a stimulant, so it causes a fast heart rate.

Moreover, smoking can cause adverse changes to the heart, lungs, and blood vessels. For example, smoking causes the veins and arteries to constrict and lose some of their elasticity, which reduces the efficiency of the cardiovascular system.

To compensate, the heart must work harder and beat faster to pump enough blood and oxygen to the body’s tissues.

#4: Stress

Physical, mental, and emotional stress can all trigger the sympathetic division of the autonomic nervous system, or the “fight-or-flight” response, and affect your overall health.

This can increase heart rate and respiration rate. As a result, both chronic stress and acute stress can elevate your heart rate, including your resting heart rate.

A person running in a parking garage.

#5: State of Mind

In addition to your stress levels, your current state of mind or emotional presentation can influence your resting heart rate. For example, anxiety, excitement, surprise, and fear can all increase your heart rate.

Perhaps you’ve felt heart palpitations, shortness of breath, and a rapid heart rate from a stress-induced panic attack at some point.

#6: Exercise Habits

Regular exercise strengthens the heart and lungs. The heart is a muscle, and like other muscles in the body, it can contract more forcefully as it gets stronger. 

When the heart muscle contracts more forcefully, stroke volume increases, which means the heart can pump more blood—and thus oxygen—out to the rest of the body every time it beats.

This can effectively reduce resting heart rate because the heart becomes more efficient. If you are an avid athlete, you may actually wonder why you have a low heart rate at rest!

two people hydrating after exercising.

#7: Temperature and Environmental Conditions

In hot and humid conditions, your heart has to work harder to cool your body down. The heart beats faster to bring more blood flow to the skin’s surface and produce sweat to help drop your core temperature. Therefore, your resting heart rate increases on hot days.

Similarly, if you have a fever or are sick, your resting heart rate will be higher because your heart has to work harder to cool you down.

#8: Hydration Status

Dehydration can increase your resting heart rate because your blood plasma level decreases as your body water drops.

When less blood moves through your circulatory system, your heart has to pump faster to maintain your core temperature and deliver enough oxygen and nutrients to the body.

#9: Medications

Certain prescription and over-the-counter medications can affect your resting heart rate and cause either tachycardia or bradycardia.

For example, beta-blockers or high blood pressure medication tend to lower your heart rate, while certain stimulants and psychoactive medications can increase it.

A person looking at their phone after running.

Why Is My Resting Heart Rate So High?

Now that we’ve covered the primary factors that affect resting heart rate, it’s easy to see that there can be several potential causes to answer your question, why is my resting heart rate so high?

If you smoke, are dehydrated, are under chronic or acute stress, or are in a warm climate, chances are your resting heart rate is going to be higher than the normal target heart rate levels.

However, for runners, there’s an additional factor that can influence heart rate: training status. 

During recovery from exercise, your sympathetic nervous system has to work harder to restore homeostasis. Your heart beats faster to circulate enough reparative oxygen and nutrients to your skeletal muscles to repair damage and promote recovery. 

The hormonal profile after a workout lends itself to a higher heart rate, as hormones like epinephrine (adrenaline), which are produced during physical activity, stimulate an increase in your heart rate.

When you are fully recovered from a run or workout, your resting heart rate returns to baseline because your tissues have received adequate perfusion, and your hormones should have returned to resting levels. 

Recovery from a workout typically takes a couple of hours, depending on the intensity and duration of the workout, your nutritional status, sleep, hydration, and overall training level. As you recover, you will lower resting heart rate levels back to baseline. 

A person on a treadmill.

However, when one is overtrained and underrecovered, this recovery process gets drawn out. Chronic overtraining can leave the body in a state of incomplete recovery, which can be reflected in a higher resting heart rate.

Therefore, if you are training hard but all other aspects of your health and life are relatively stable, a high resting heart rate can indicate overtraining.

A sudden increase in your normal resting heart rate can also be a sign that you’re getting sick and your heart is working harder to stave off illness.

With this in mind, monitoring resting heart rate can be a valuable practice for runners. It can provide a window into one’s training status and the potential need for more rest.

Of course, you should contact your healthcare provider if you are concerned that your resting heart rate is too high, as it could be indicative of a medical condition and possibly put you at a higher risk for cardiovascular disease or a heart attack.3Solan, M. (2016, June 17). Your resting heart rate can reflect your current and future health. Harvard Health. https://www.health.harvard.edu/blog/your-resting-heart-rate-can-reflect-your-current-and-future-health-201606172482#:~:text=In%20fact%2C%20research%20has%20found

To get on track with a healthy diet and a healthy heart, check out our guide to the Medeterrainean diet:


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Amber Sayer is a Fitness, Nutrition, and Wellness Writer and Editor, as well as a NASM-Certified Nutrition Coach and UESCA-certified running, endurance nutrition, and triathlon coach. She holds two Masters Degrees—one in Exercise Science and one in Prosthetics and Orthotics. As a Certified Personal Trainer and running coach for 12 years, Amber enjoys staying active and helping others do so as well. In her free time, she likes running, cycling, cooking, and tackling any type of puzzle.

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