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Heart Rate Zones (HRZ) - What is it and how do you use it?

Are you looking to take your training to the next level? Have you seen workouts that specify which heart rate zone to stay in? Are you wondering which zone you should train in?

This article will explain what heart rate zones are and how to use them. Most importantly, it will keep it very simple for everyone to understand.

The terminology

HR - heart rate - Someone might ask you what your heart rate is. This is the measure of how many beats per minute your heart is beating. The greater the number the greater intensity you're exercising.

HRZ - heart rate zone - See the next section.

BPM - beats per minute - When telling someone what your heart rate is, you will express that in beats per minute. Well conditioned athletes might have a resting heart rate of 45-65 bpm.

What are Heart Rate Zones?

Imagine you sleeping in the middle of the night. You're extremely calm and relaxed. Your heart rate barely beats because you're not taxing your body. Now imagine you're being chased by a bear. You're running for your life. Your heart rate will be beating out of your chest. Heart Rate Zones take your lowest heart rate and your maximum heart rate and break the difference into several groupings or zones.

If you look online you will see 5 (1-5) or 6 (1-6) zones. You may even see 7 (1-4, 5a, 5b, 5c) zones. Any one of those zone structures is fine. If you have too few zones you aren't controlling your heart rate enough. If you have too many zones, you are making it too difficult to stay in a zone while running or cycling. Going up a super slight hill will add a few beats to your heart rate and put you outside of your intended zone.

TVTC typically uses the 7 zone structure of zones 1-4, 5a, 5b, 5c. But sometimes the other zone structures are used as well.

When and why do you use Heart Rate Zones?

You can use heart rate zones any time you run or cycle. As was mentioned in the RPE blog post, to improve your running or cycling you must vary your efforts during your workouts. One way to identify your effort level is by using your heart rate. Thus having zones for your heart rate will keep it easy for you to follow prescribed effort levels.

When you join TVTC as a member or purchase a training plan you will see run and bike workouts. These workouts will mention an HRZ (or Zone or Z). It will tell you the duration to run at each effort level. Following this as closely as possible will lead to greater speed improvements in a shorter time period.

Is Heart Rate Zones better than RPE or Rate of Perceived Exertion?

Yes and no. Both can be inaccurate if you're not fully recovered from previous workouts, or if you are sick or overly stressed. If you're someone who listens to music when you run, your perception of your intensity could be inaccurate as your mind is distracted.

Most members in TVTC train with heart rate over RPE. The majority of triathletes/runners will train with heart rate over RPE as well. Thus, one could argue that heart rate is "better". Or, maybe it's just "easier" when you have a device telling you how hard you're working. The best would be using both together.

For more information on RPE, check out our blog post.

Problems with training with Heart Rate

In the previous section, we touched briefly on the problems with using your heart rate. One problem with your heart rate is that it lags behind your effort. Imagine you are standing around talking to friends. Your heart rate is pretty low. Now, imagine you quickly start to sprint for 100 yards. Do you think your heart rate will instantly go from 60-70 bpm to 140-160? NO! It might take 10-20 seconds for your heart rate to catch up. So, if you are running (or cycling) short intervals your heart rate won't give you accurate numbers for the effort you are running (or cycling).

Another problem occurs when you are overly stressed or sick. Your body is being taxed by other stresses beyond the exercise. It might just beat 5-10 beats lower than normal for a given effort. Therefore, you might run harder to increase your heart rate to the right zone, but you would now be running too hard. Obviously, this is not what you want. This same condition can occur when you are not recovered enough from previous workouts.

How do you measure your heart rate when exercising?

One way to measure your heart is by stopping and taking your pulse with your fingers and a stopwatch. This is just inaccurate and cumbersome when running. So, don't do it. :)

The best way is to use a heart rate monitor with a heart rate strap. The heart rate strap is key. Now with the iWatch and similar watches, it can determine a heart rate using an optical sensor. This is not as accurate during exercise due to the movement of the watch on your wrist, or the perspiration under the optical sensor. There are many brands that have great heart rate monitors. The most common brand is Garmin. The latest model dedicated for triathletes is the Garmin 945. Of course, there are cheaper models.

How do you calculate Heart Rate Zones?

There are many ways to calculate your heart rate zones. One such way is to go to a lab that does it scientifically. But, this costs a lot of money and isn't realistic because you're indoors and running on a treadmill. However, this is a useful thing to do every 2 years or so to measure your improvement.

Another way is by doing a specific test out on a track. The exact method is outside the scope of this article. If you are a member of TVTC then you will get your zones calculated for you during a practice.

TVTC recommends using the zones that the heart rate monitor calculates. These watches/monitors do a great job since they are more accurately looking not only at your heart rate, but subtle changes in how it beats to determine your zones.

Tell us below your experience with training with heart rate zones and how they were calculated.

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