How To Tell If Your In The Zone 2 Cardio Threshold During Workouts—And Why It Matters
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links."
Athletes often throw around the term Zone 2 cardio, referring to their lower-intensity workouts. But everyone can benefit from this form of exercise—whether you're training for a marathon or want to make sure you get in to recommended 150 minutes of aerobic activity a week.
Zone 2 cardio training is a type of steady-state aerobic workout that’s typically performed at an easy to moderate level of intensity, says Melissa Kendter, CPT, ACE-certified personal trainer, functional training specialist, and UESCA-certified run coach.
The good news: You can try the cardio method with just about any type of workout that can keep your heart rate consistently elevated, she says. That means Zone 2 cardio can be running, hiking, cycling, swimming, rowing, skating, and elliptical training. Even rollerblading and walking your dog can count.
Zone 2 cardio training may be a lower-intensity sesh, but it comes with major benefits for your health and performance. Here’s what to know about the workout style and how to add it to your routine.
Meet the expert: Melissa Kendter is an ACE-certified personal trainer, functional training specialist, and UESCA-certified run coach. Kendter is also the creator of EvolveYou app's Commit Programs.
What is Zone 2 cardio?
This training method (also known as low intensity steady-state, or LISS, cardio) will typically get your heart rate between 60 to 70 percent of your heart rate max, says Kendter. It's designed to keep your heart rate at a fast, but sustainable rate. At that level, you'll feel like you’re breathing a bit harder than usual but still able to carry out a conversation, she adds.
Benefits Of Zone 2 Cardio
It improves heart health. As a workout that calls on your large muscle groups, is rhythmic, and can be maintained continuously, Zone 2 cardio can be classified as an aerobic workout. As you train, your body will utilize oxygen to create the energy needed to fuel your muscles, says Kendter. Aerobic exercise has been shown to improve lipid profiles (increasing HDL/good cholesterol levels), per World Journal of Cardiology research, and insulin sensitivity, according to research published in Oxidative Medicine and Cellular Longevity. And in individuals with cardiovascular disease, it’s been found to reduce mortality related to the disease and decrease the risk of myocardial infarction, according to a Frontiers in Cardiovascular Medicine study.
It builds your endurance. Consistently hitting Zone 2 cardio can help you build your aerobic base, says Kendter. As a result, you’ll increase your cardiovascular fitness, improve your body’s capacity to generate energy from oxygen and deliver it to your working muscles, and boost your ability to perform steady-state work for a long period of time, she explains. In other words, the more volume you have training in Zone 2, the longer you’ll be able to run, swim, or bike without feeling winded.
It improves performance and power. Zone 2 training can also help you perform better at higher intensities, says Kendter. Here's how it works: Aerobic exercise increases the number and size of mitochondria (which use oxygen to create energy) and causes your muscle capillaries (which supply your muscles with oxygen-rich blood) to grow, per research in Statpearls. Thanks to your body’s improved ability to deliver and use oxygen, you’ll see a boost in performance in other aspects of your fitness routine, she says. “It then helps to improve your power output at higher intensities, your efficiency, and your overall strength,” she adds.
It’s less likely to cause burnout and overtraining compared to more intense modalities. Zone 2 cardio is challenging enough to drive meaningful adaptations, but it’s not so taxing on your body that it’s difficult to recover from, says Kendter. Thanks to this just-tough-enough intensity, you’re less likely to experience total fatigue and overtraining with Zone 2 cardio, she adds. “Becoming a more agile, well-rounded person is really about building your [aerobic] base in that Zone 2 training,” she notes. “Because if you do hard efforts all the time, you'll overdo it. That's when it can lead to overtraining, injuries, or eventually a drop in motivation just because your body burns out.”
How To Know If You’re In Zone 2
Whether you’re running, rowing, walking, or biking, the best way to tell if you’re working in Zone 2 is to simply look at your heart rate, says Kendter. Remember, your heart rate should be 60 to 70 percent of your HR max. To estimate your HR max, multiply your age by 0.7, then subtract that number from 208. Then, take 60 and 70 percent of that number to determine your Zone 2 heart-rate range.
How to calculate your Zone 2 cardio range:
Lower threshold: 0.6 x (208 - age x 0.7)
Upper threshold: 0.7 x (208 - age x 0.7)
For example: If you’re 25 years old, your Zone 2 training heart rate should be roughly 114 to 133 beats per minute, which you can monitor using a heart-rate monitor, chest strap, or similar tracking device.
Heart Rate Zones, Explained
Zone 1
Your body is using glucose, fatty acids, and amino acids as fuel. You're working at a very low intensity, about 50 to 60 percent of your max heart rate. Your rate of perceived exertion (or RPE)—a scale used to measure the intensity of your exercise, from one to 10—is a one or a two.
Zone 2
Your body is still using glucose, fatty acids, and amino acids as fuel. You're going at a low intensity, but more like 60 to 70 percent of your HR max, with a RPE of three to five.
Zone 3
Your body is still using glucose, fatty acids, and amino acids as fuel, but you're at a moderate intensity. Think: 70 to 80 percent of your HR max, and a RPE of six.
Zone 4
Your body is eating up glucose as fuel. Now, you're working at a high intensity: 80 to 90 percent of your HR max, and a RPE in the seven to eight range.
Zone 5
You're using glucose as fuel. Zone 5 is your all-out intensity, or 90 to 100 percent HR max and a RPE of nine or 10. Your toughest effort!
If you're gadget-free, you can also use the talk test—talking aloud while exercising—to determine your intensity. “You should be able to hold a conversation during Zone 2 training," says Kendter. "You shouldn't be gasping for air."
And, you don't have to speak out loud to test your range either. "I always say you should be able to inhale for three to four counts and exhale for three to four counts, and that means that you're in the proper zone,” says Kendter. This method is ideal for cardio beginners, as their heart rate will naturally be a bit higher even when they’re working at a lower intensity, she adds.
At some point during your workout, you might notice your heart rate jumping out of the zone or it becoming more difficult to talk, which could be due to dehydration, a sudden increase in the workload, or environmental factors, like an increase in temperature, says Kendter. In this case, slow yourself down to stay in Zone 2. “If you need to stop and walk or take a break from whatever you're doing, take a break and then come back in a minute,” she suggests. “Or just slow it down until your heart rate lessens or you're able to talk or breathe normally again.”
Does Zone 2 training burn fat?
Zone 2 cardio training is often called the “fat-burning” zone, and that’s true to an extent, says Kendter. “It's your body's way of utilizing fat as an energy source so that you're able to run longer, walk longer, swim longer, or cycle longer," she says. "It's not actually burning fat off your body. That's a big misconception going on.”
Why is Zone 2 training important?
Zone 2 cardio training offers a handful of health benefits (see above). It supports your heart health, improves your endurance so you can bike around town for hours on end without feeling exhausted, and boosts your body’s ability to deliver and utilize oxygen during exercise. Plus, it’s relatively easy on the body, so you won’t feel burnt out if you do it consistently.
Is Zone 2 training good for weight loss?
Zone 2 cardio can help you achieve your body composition goals (read: weight loss), says Kendter. “Because you can do it daily, Zone 2 training will absolutely improve your body composition because you're moving your body more,” she explains. Not to mention, you’re more likely to stick with physical activity—such as lower-intensity Zone 2 cardio—that feels enjoyable and sustainable, so you may see more progress in the long run.
But, Zone 2 training doesn’t target body fat specifically, and higher-intensity activities generally burn more calories per minute than their lower-intensity counterparts. Those higher intensity activities can be a better option for weight loss, as a result.
How long should a Zone 2 training workout be?
Generally speaking, a Zone 2 cardio workout should be at least 20 to 30 minutes, and you can gradually progress to 60-minute sessions as your fitness improves, says Kendter.
How often should you do Zone 2 cardio per week?
If cardio isn’t your jam, you don't have to do it every day of the week. Instead, try to incorporate Zone 2 training into your routine twice a week to score the cardiovascular and performance benefits, suggests Kendter.
Whether you decide to bike, hike, or rollerblade, just remember to keep your heart rate steady and your effort low enough that you can still belt out the latest Taylor Swift album.
Can you do Zone 2 cardio every day?
Yes, you absolutely can. Zone 2 cardio is low-intensity, so you’re able to do it every day without any serious repercussions, says Kendter. “If you're training for a marathon, an Ironman, or just improving your fitness, you can definitely go for a brisk 20- or 30-minute walk every single day—and that's Zone 2 training,” she adds.
You Might Also Like
