Why Is My Heart Rate High On Easy Runs?

If you are a runner that follows your heart rate closely, you may have experienced days where your heart rate is higher than normal.

Heart rate can fluctuate due to many reasons. Because of this, it can provoke uncertainty among runners when their heart rate is outside their normal parameters.

Since your heart rate can rise on easy and long runs for various reasons, it is helpful to understand the sources of these fluctuations.

Knowing what causes a higher than normal heart rate during your runs means you can identify solutions and allow you to adjust your training on the day.

In this article, we will discuss:

– What an easy run is
– Why your heart rate may be high on easy runs
– Factors that increase Heart rate
– How to lower your heart rate when running

What Is An Easy Run?

An easy run (sometimes called a recovery run), is a run that is done at low intensity. This intensity is very controlled and performed at a comfortable pace.

An easy run (recovery run) is usually under 45 minutes duration. Thus, shorter than most of your other runs. Your heart rate should also be kept under 76 percent of your threshold heart rate. Hence, the effort should be kept relatively low to promote recovery.

Most easy runs are performed over flat terrain. This is to control the heart rate better and place less stress on the body and muscles.

Since easy runs are primarily for recovery, most runners will include these types of runs into their training a few times per week.

Factors That Increase Heart Rate

During some runs, especially during easy runs, you may find your heart rate fluctuates. This can sometimes cause concern for the runner. So we have included some of the reasons your heart rate may be higher than normal during an easy run.

High Altitude
If you are training at high altitudes, you may notice your heart rate is much higher than normal. Because there is less oxygen for the body to consume, it makes the bodywork harder to transport oxygen to the muscles. This results in an increased heart rate when you run.

Heat & Humidity
Running in hot and humid conditions can also significantly affect your heart rate. Hot and humid conditions can cause the body’s temperature to rise, which causes the body to try to cool itself down. This puts the body under more pressure, thus causing your heart rate to rise on a run.

Dehydration
Dehydration is one of the most common causes of high heart rates in runners. Regardless of the weather conditions, it is easy to become dehydrated if you don’t regularly drink before, during, and after your run.

The early signs of dehydration are sometimes hard to detect in runners, especially if the weather is colder. However, one sign that is common among runners is a higher heart rate than normal.

Cardiac Drift
Ever noticed your heart rate increasing gradually during a run, even though you are holding the same pace. This is called cardiac drift.

The gradual climb in heart rate is caused by your body’s skin blood flow increases. As the body tries to cool itself down, heart rate will naturally rise. This can start as early as 30 minutes into your run.

Lack of Sleep
Lack of sleep and being overly tired can not only affect your training. It can also raise your heart rate. In most cases, lack of sleep can cause your heart rate to climb as much as 5 to 10 beats per minute more than normal

Stress
Another factor that can fluctuate your heart rate is stress. Stress will not only make your heart rate higher when you run, but it will also increase it throughout the day.

Even though exercise is one of the best stress relievers, daily life can take its toll and outweigh the benefits of exercise.

Why Is My Heart Rate High On Easy Runs?

If you follow a training plan which incorporates a few easy runs each week, you may have days where your heart rate is higher than normal. This can be just a few beats per minute, or even 10bpm or more. While this is common, it shouldn’t be a regular occurrence.

So, why is my heart rate high on easy runs?

As we discussed above, there are many causes of your heart rate being higher than it usually is. This could be:

– Lack of sleep
– Dehydration from previous workouts
– Fatigue
– Heat
– Humidity

However, since many variables can cause your heart rate to fluctuate, it is sometimes hard to pinpoint the cause of the increased heart rate.

If you feel recovered and your stride feels lively, you may want to change from heart rate to Perceived Exertion (RPE). RPE can help you run by feel when your heart rate is influenced by other factors.

However, if your easy run is for recovery, slow it down regardless. The goal of an easy run (recovery run) is to promote recovery, which means intensity should be kept low at all times.

If you find your heart rate is higher than normal on every easy run, you may need to look at your training plan. You may not be allowing enough recovery between sessions or doing the easy sessions too hard. When this happens, fatigue builds up over time. This can cause your heart rate to be much higher than it usually is.

If this is the case, take a week off running, let the body recover and then adjust the structure of your training.