Want to Plan Your Workouts More Effectively? Zone Training Can Help

Everyone’s got a type—an exercise type, that is. Maybe yours is an interval or HIIT workout that’s fast-paced and nice and sweaty. Or, perhaps you prefer endurance workouts where you can zone out and listen to some good music.  

No matter what type of classes you love, you’re probably pretty attuned to what your heart rate is during a workout. For example, you know that a low-impact ride may keep your heart rate lower than a Tabata ride. Or, a recovery run is going to keep your heart rate steady compared to an interval session. 

These heart rates are falling into what’s often referred to as cardio zones, or training zones. Here, Peloton instructor Christine D’Ercole explains exactly what training zones are, why they are different for everyone, and why you shouldn’t stick to one zone for too long. 

What You Need to Know About Training Zones

Training zones are methods of measuring your exercise intensity. The most common training zones used are heart rate zones (also called cardio zones) or rate of perceived exertion (RPE). Both training zones have their benefits and drawbacks.

What Are Exercise Heart Rate (Cardio) Zones?

As you train, your heart rate, or the number of times your heart beats per minute, will spike and dip. This can be categorized into five different zones. 

The simplest way to calculate these cardio zones is by first figuring out what their max heart rate is. There are two methods to doing this. The first is subtracting your age from 220. There is also a method called the Karvonen method, which helps you find your heart rate reserve—your maximum heart rate minus your resting heart rate. Your heart rate reserve number is helpful when it comes to understanding what target heart zones you want to achieve for different workouts. For example, if you’re doing a vigorous intensity workout, you’d aim for your target heart rate to be between 70 percent to 85 percent of your max heart rate. To get this number, you would multiply your heart rate reserve by .70 or .85 and add that number to your resting heart rate. This is now your target heart rate zone for that workout.

However, Christine says the problem with focusing solely on your heart rate is that even if you have a calculated number in front of you, it may be incorrect. “[This equation] doesn’t account for weight, level of fitness, or years of conditioning,” she says. “Your heart is also going to respond differently to a full body exercise as opposed to a predominantly lower body exercise.”

What Is a Resting Heart Rate?

Your resting heart rate is the number of times your heart beats per minute (BPM). For the average adult, this can range anywhere from 60 to 100 beats per minute. 

Resting heart rate is another tricky number to focus on, because it is very unique to the individual. Research published in PLos One looked at over 90,000 individuals who tracked their heart rates for at least 20 hours a day for a median of 326 days (up to 730 days). The research found that resting heart rate between both sexes varied from 40 BPM to 109 BPM, and many factors like age, sex, BMI, and even sleep all affected resting heart rate over time.  

Similar to the issue with finding your max heart rate, there is no “normal” resting heart rate. 

What is Rate of Perceived Exertion (RPE)?

Another way to understand training zones without using heart rate is to do it based on how you feel. This will be different for everyone, because again, we’re all starting at different fitness and cardiovascular levels. However, understanding your RPE (also referred to as the Borg RPE scale, or the more commonly used Modified Borg scale) within these five cardio zones can help maximize the way you train.

Choosing the Right Training Zone Method for You

Cardio Zones

Use heart rate zones if you’re data motivated and typically work out with a heart rate monitor or fitness tracker that measures heart rate. 

RPE Scale

If you prefer not to track your heart rate or find that heart rate zones aren’t as accurate for you, you can use Christine’s preferred method, the RPE scale. The modified RPE scale ranges from 1 (very light activity) to 10 (max effort).

The guidelines below will help determine what zone you’re exercising in.

Zone 1

As the number might suggest, zone 1 is the easiest zone, 50 percent to 60 percent of your max heart rate. If you’re judging by RPE you will be at a 1, Christine says that zone 1 is equivalent to waking up and getting out of bed calmly. This can also be the first few minutes of a ride, row, or run, when you’re using light resistance and a high cadence to warm up the muscles.

Zone 2

Zone 2 training is often referred to as base training. You’ll be at between an RPE of 2-4 and it’s about 60 percent to 70 percent of your max heart rate, a good zone for endurance training. Christine says this is a zone that is aerobic but conversational, meaning you can carry a conversation and should be able to keep this pace for about an hour or a longer time depending on your fitness level.

Zone 3

Training in zone 3 moves you into that 70 percent to 80 percent max heart rate range and an RPE of 5-6. For many, this will be on the high end of that aerobic training. You can still speak, but in short, choppy sentences and you’re starting to feel winded.

Zone 4

Zone 4 is a hard effort, 80 percent to 90 percent of your max heart rate, an RPE of 7-8 and crossing over from aerobic, endurance exercise to anaerobic, says Christine. In this zone, you’re doing short bursts of sprints or high-intensity exercise but you can only hold this effort for a few minutes (this can tick upwards to 10-20 minutes depending on how conditioned you are).

Zone 5

The average athlete will hit zone 5 briefly, as this is an all-out sprint using 90 percent to 100 percent of your max heart rate and clocking an RPE of 9-10. Christine says a good way to know if you’ve reached zone 5 is you’re doing a sprint which you can hang on to for only about 15 to 30 seconds. With zone 4 to 5 training in particular, remember that you need to factor in enough recovery time. “The harder you work, the less time you can spend at that intensity, and the more recovery you need between efforts,” says Christine.

Is There a Cardio Zone That’s Best for Overall Cardiovascular Health?

Zone 2 has been touted as the cardio zone that has the most benefits to your cardiovascular health. But remember, each person has a unique set of cardio zones. This means that a zone 2 for one person may be a zone 4 for another.  

The Benefits of Zone Training

Zone training can help you observe how your body responds to the different zones over a long period of time—starting anywhere from three to six months.

“As you develop your cardiovascular endurance and strength, you’re going to be able to handle higher heart rates [and cardio zones] for longer,” says Christine. “You're going to be able to physiologically tolerate what may have felt panicky and uncomfortable. Your body will learn to manage and adapt because your heart muscle will literally get stronger as will your cardiovascular health. Your entire system will start to work more efficiently.”

The secret to achieving this, however, is making sure you have a well-rounded fitness routine—one that covers every training zone and incorporates strength training. “A periodized program with a range of intensities every week for a couple of months at a time can help you track your growth and the goals attached to it,” says Christine.

What Each of the Training Zones Achieve

Zone 1-2 or RPE 1-4

These base zones are key for warmup and recovery. Here, Christine says you are working on your endurance. You may burn less calories because you’re working at a lower intensity, but you can sustain this pace for a longer length of time. 

Zone 2-3 or RPE 2-6

Christine says these zones are the aerobic zones, and that conversational pace you experience in zones 1-2 is getting difficult to maintain. For seasoned athletes, this may still be an endurance zone, while for others, you may find yourself getting more winded. Aerobic training circulates blood around the body quickly (which is why you find yourself breathing faster), using oxygen to fuel your muscles and keep moving. This type of exercise helps reduces the risk of cardiovascular disease.

Zone 3-4 or RPE 5-8

For many, zones 3-4 begin to cross into anaerobic training. You can no longer hold your pace for an hour or more. Anaerobic exercise doesn’t require the same amount of oxygen that you needed in zones 1-3. Instead, you’re getting power from the energy (glucose) in your muscles. The anaerobic zones help reduce fat and increase muscle mass. 

Zone 4-5 or RPE 7-10

These zones are what Christine refers to as the lactate threshold. You’re not holding this pace for very long, but it’s important to push yourself into these zones. This type of training can improve your aerobic and anaerobic fitness, so you’ll be able to exercise longer and harder in future sessions. 

Why You Should Target Different Training Zones

No matter what types of workouts you love to do, you need to find a way to exercise in all of the cardio zones. “If you are an endurance athlete, it is still good for you to do sprint work and the higher intensity work,” says Christine. “If [you only train one way], then that's all you'll have.”

If you love intervals and HIIT, that means you also need to do longer, endurance-based workouts. Christine says to figure out what your goals are (i.e., Do you want to run a marathon, or PR in a 5K?), and build from there. “Even though I do a lot of sprint training now, I [make sure to] still do my long rides,” she says. “There is no best zone, because it only has to do with what you're training for and what your goals are. If your goal is basic cardiovascular fitness, then you want to train the entire range.”

How to Work Out in a Target Cardio Zone

In order to train in all the cardio zones, make a well-rounded program that incorporates endurance cardio, interval, tempo, or HIIT training, in addition to strength training. Using the Bike as an example: “A well-rounded basic routine would be a longer 45 to 60-minute ride, some HIIT or Tabata rides, and then lower intensity recovery days,” says Christine. Keep in mind that on strength training days (which can be slotted into lower intensity days) your heart rate will jump around the different cardio zones based on what moves you are performing, such as a chest press (which is more a zone 1-2) versus a box jump (zone 3-5), says Christine.

Do You Need to Track Your Heart Rate During Exercise?

While Christine says it’s not important to be laser-focused on hitting target heart rates during a workout (especially if number crunching and all that data stresses you out instead of motivates you), it’s still a good idea to monitor your heart rate when you work out. “The key is to track your heart rate long-term, because as you improve your cardiovascular endurance and strength, you’re going to be able to handle higher heart rates for longer,” she says.

There are other things to be aware of too when you train, such as the amount of sleep you’re getting, hydration, and even your stress levels. Christine says these factors can all impact heart rate during exercise. (So, if your heart rate is higher during an endurance workout than normal, consider how much water you’ve been drinking that day or how many hours of sleep you got the night before.) Being aware of how you feel overall will help explain your performance during a specific workout as well as gauge your own personal cardio zones.

How Specific Exercises Relate to Cardio Zones

To understand how exercises fall into cardio zones, and often run a range of cardio zones in one class or workout, try taking Peloton’s Power Zone Rides on the Peloton Bike and Bike+. (You can start with the Discover Your Power Zones Collection here.) “In Power Zones, we use the terms endurance [zone 2], tempo [zone 3-4], and lactate threshold [zone 5],” says Christine. Zone 3 to 4 is the bridge from aerobic to anaerobic exercise, where you can no longer hold that pace for an hour. Zones 4 to 5 will push that intensity even more. “[This is where] you are producing lactate but not flushing it at a rate that would allow you to go beyond that duration of time on the bike,” says Christine.

These same buzzwords can be used to give you a clue on what cardio zones you’ll be in for other types of exercise, too. For example, an endurance run, ride, or row will have you in zones 1 to 3, while tempo, HIIT, and interval workouts will go into zones 3 to 5.