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It’s not often you hear someone ask what heart rate zone you’re running in, even if you’re clearly wearing the latest heart rate monitor or activity-tracking tech. But with heart rate data more accessible than ever (think: OrangeTheory classes, wrist-based devices, and treadmill training software), more runners are tuning into their heart rate zones and wondering how doing so can enhance their performance.
Heart rate training—and knowing your heart rate zones—can be a smart technique to guide your intensity during training and working your various energy systems depending on your goal, says Heather Milton, C.S.C.S., an exercise physiologist and high performance board member for USA Football.
“I think heart rate training really helps make your easy workouts easier, your hard workouts harder, and ensures that you’re actually working out at the correct intensity for your goal,” says Becca Capell Nielsen, a NASM-certified personal trainer and vice president of product experience at iFit.
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What is heart rate training?
Heart rate training uses—surprise—your heart rate, measured in beats per minute (bpm) or as a percentage of your maximum heart rate (MHR), as a guide for intensity. “Using that individual heart rate, you create specific training zones that help determine your intensity for a given workout,” explains Capell Nielsen. So instead of training by pace, you use personalized heart rate zones and a heart rate monitor to ensure your cardiorespiratory system is working at a specific effort for a set amount of time.
The idea behind heart rate-based training is to train your aerobic system without over-stressing your skeletal and muscular systems. By working out in each heart rate zone, you’re making sure you’re not just pushing yourself to the max, you’re also holding yourself back from pushing too hard, which can help you avoid overtraining. And since your maximum heart rate is unique to you, using it to create training heart rate zones means you’re getting a much more personalized workout.
How do you find your heart rate zones?
Your heart rate is one of the most accurate measurements of intensity and effort during a workout. Finding a good heart rate for training in each zone can help improve your performance. Everyone has a resting heart rate, which is best measured when you first wake up, and a maximum heart rate, or the upper limit of what your cardiovascular system can handle during physical activity. Between these two values are different heart rate zones that mark your effort.
The most accurate methods to find your MHR are in a lab test, which is conducted by professionals with fancy equipment, or in a field test, which is often supervised by a certified trainer in a gym setting with a treadmill or indoor bike.
To find your heart rate zones on your own, the first thing you’ll need to do is calculate your MHR, maximum heart rate. You’ve probably seen one longstanding formula for this: 220 minus your age, but the best equation currently available for the general population is [208 – (0.7 x age)]. There are various models of heart rate training zones (all with their own labels), but most non-elite runners follow five heart rate zones established by heart rate monitor company Polar, based on research from the 1970s. There are five zones: very light, light, moderate, hard, and very hard. Here’s how the numbers stack up:
- Zone 1: Very light, 50 percent to 60 percent of MHR
- Zone 2: Light, 60 percent to 70 percent of MHR
- Zone 3: Moderate, 70 percent to 80 percent of MHR
- Zone 4: Hard, 80 percent to 90 percent of MHR
- Zone 5: Very hard, 90 percent to 100 percent of MHR
To calculate your personal zones, there’s some easy math involved: Just multiply your max by the minimum and maximum percentages indicated by each zone.
But if you don’t feel like doing all that math, you can use the three heart rate zones provided by the American College of Sports Medicine, says Milton:
- Aerobic training: 50-70 percent of MHR
- Tempo and threshold runs: 71-85 percent of MHR
- Intervals: >85 percent of MHR
Heart-Rate Training Helpers
Polar Vantage V2
Garmin HRM-Tri Heart Rate Monitor
How to Benefit from Following Heart Rate Zones
First of all, don’t worry about heart rate training before you’ve got a solid base of at least four to eight weeks of running, says Milton. “The chances of beginners being able to stick to a specific heart rate while starting out is low, and may become discouraging,” she says.
But once you’re comfortably logging miles, each heart rate zone serves a purpose in your training. “Using heart rate to determine tempo, threshold, and intervals intensities can improve biomechanical efficiency and speed,” says Milton. So many runners tend to ignore intensity and just rack up training miles at a middle-of-the-road intensity that doesn’t help them—and may even hold them back—on race day. In a heart rate training plan, you calculate the appropriate intensities, then you just adjust your pace to ensure that your heart rate stays in that zone, says Capell Nielsen.
Here’s how those zones break down in terms of workouts:
Zone 1 should be easy; “it’s a great intensity level for recovery days,” says Capell Nielsen. You should feel like you could maintain your zone one intensity for hours.
Zone 2 is meant for runs under 90 minutes; these longer, slower efforts serve as aerobic conditioning for distance runs, says Milton. It’s also the zone that improves your body’s ability to use fat for energy (i.e. burn fat), which makes it good for weight loss (if that’s your goal). Runners training for a half marathon or longer should aim to spend up to 80 percent of their training in this zone, adds Capell Nielsen.
Zone 3 is where your body gets the most cardiovascular benefit, and it’s sometimes referred to as the aerobic zone, says Capell Nielsen. “When it comes to developing stamina and increasing aerobic capacity, zone three is the magic spot.” Tempo runs, which are still predominantly aerobic, fall into zone 3, and generally last 30 to 45 minutes.
In Zone 4, you’re using more of a mix of aerobic and anaerobic metabolism, says Milton. These threshold runs help your body gets better at using carbs for energy and learn to withstand higher levels of lactate in the blood. “When it comes to boosting your performance and increasing your lactate threshold, training in zone four is a must,” adds Capell Nielsen.
Finally, Zone 5 is your high-intensity intervals that last under five minutes, says Capell Nielsen—you literally shouldn’t be able to continue for longer. That’s because if you want to run faster, you need to run faster—and high-intensity intervals help you maintain or improve your max heart rate so you can push yourself harder on race day.
The key is that you should be training in all of these heart rate zones at different times in order to maximize your performance. Your intensity and your heart rate zones all depend on your health, performance, race goals, and workout preferences. Make sure to work with a professional if necessary.
