What is Zone 2 Training?

In a fitness world filled with calorie-shredding, high-intensity workouts, it's easy to overlook the fact that when it comes to cardio, we might need to go slow to get fast results. That’s where moderate-intensity exercise, or zone 2 training, has a chance to shine.  

You may have heard the zone 2 cardio buzzword in popular TikTok trends or even from thought leaders in the fitness space. Zone 2 training refers mostly to cardio exercises that are performed at 60 to 70% of your maximum heart rate. If you’re not sure what that is, we’ll walk you through how to design a zone 2 workout that’s right for you.  

Zone 2 Training 

To understand zone 2 training, let’s first explain the different heart rate training zones. There are five zones in total, with zone 1 being the easiest and zone 5 being the hardest. Each heart rate zone has a corresponding target heart rate range.  

Zone 2 training is just above a leisurely walking pace, but before you start to feel breathless while running, which is equal to about 60 to 70% of your maximum heart rate.  

Most of us haven’t taken an exercise stress test, so we may not know our exact maximum heart rate, much less what 60% would be for zone 2 training. Therefore, a reliable predictor of a cardio zone is the rated perceived exertion scale, or RPE scale, which helps you rate how hard your workout feels. 

In research studies, RPE is typically represented on a scale from 6 to 20. Though, a 10-point scale is commonly posted in gyms and on cardio equipment, where an RPE of 4 to 6 would represent zone 2 exercise. In this zone, your heart rate and breathing increase, but you can still speak in short sentences and you don’t feel breathless.   

How Much Zone 2 Training Should I Do?  

If you define zone 2 training as moderate-intensity exercise, then the Physical Activity Guidelines for Americans recommend 150 minutes to 300 minutes per week for adults.  

The Guidelines also state that 150 minutes per week is a minimum and aiming for at least 300 minutes offers additional health benefits such as decreased risk of heart disease, diabetes, and certain types of cancer.  

You also aren’t stuck doing 60-minute cardio workouts if that doesn’t fit your schedule. As long as you accumulate at least 150 minutes per week, you will start to experience the benefits of zone 2 exercise.  

Benefits of Zone 2 Training 

Unlike the latest fitness fads, zone 2, or moderate-intensity exercise, is backed by decades of research showing its connection with decreasing risk for chronic diseases like heart disease and diabetes as well as many types of cancer.  

Here are two interesting things you may not have heard about zone 2 training: Did you know that increasing your amount of zone 2 exercise can help prevent your risk of exercise injury? Not only is zone 2 training less stressful on the joints than high-impact movements like you would get in a boot camp-style class, an increased amount of zone 2 cardio can help you become more resilient against potential injury and overtraining.  

Zone 2 training can also increase the number of mitochondria in your muscle cells. Recall back to science class when you learned that the mitochondria are the powerhouses of the cell. Think of it like a little battery fueling your muscles. The more batteries you have, the better your performance will be. Zone 2 training may just supercharge your fitness. As an added bonus, zone 2 training also happens to be the ideal “fat-burning” zone in terms of energy used during a workout.  

Zone 2 Workouts

The beauty of zone 2 workouts is that you can choose whatever cardiovascular activity you enjoy, as long as you can keep your heart rate or perceived exertion in the target zone.  

Try any of these activities for your next zone 2 workout: 

• Walking or jogging 
• Cycling 
• Swimming 
• Rowing 
• Elliptical 
• Dancing 
• Tennis or Pickleball 
• Water aerobics 
• Skiing 

Zone 2 workouts can be a “set it and forget it” type of workout where you pick a comfortable pace and enjoy time listening to music, or podcasts, or watching TV for 20 to 60 minutes.  

You can also play around with resistance and speed to create a hill workout or even a type of interval workout. But remember that the key is to keep the moderate intensity and heart rate at or below 70% of your maximum heart rate.  

Below are two sample workouts.  

Treadmill Zone 2 Hill Workout: 

• Incline: 5 to 10% grade 
• Speed: 2.5 to 5 mph  
• Time: 30 minutes 

Elliptical Zone 2 Workout: 

• Speed: moderate 
• Resistance: moderate 
• Time: 30 minutes 

Start to experience the health and training benefits of zone 2 cardio today. You can find a workout that you enjoy and that fits your lifestyle. Watch as your fitness and health start to improve when you embrace going slow for faster results with zone 2 training.

References:  

1. Zinoubi B, Zbidi S, Vandewalle H, Chamari K, Driss T. Relationships between rating of perceived exertion, heart rate and blood lactate during continuous and alternated-intensity cycling exercises. Biol Sport. 2018;35(1):29-37. doi:10.5114/biolsport.2018.70749.

2. Physical Activity Guidelines Advisory Committee and United States. Dept. of Health and Human Services. Physical Activity Guidelines Advisory Committee Report, 2008: To the Secretary of Health and Human Services.

3. Kyral A, Shipherd A, Hearon C. The Effect of Moderate Intensity Aerobic Exercise on Affect and Exercise Intention in Active and Inactive College Students. Int J Exerc Sci. 2019;12(5):1070-1079. 

4. Gabbett TJ. The training—injury prevention paradox: should athletes be training smarter and harder? Brit J Sports Med. 2016;50:273-280.

5. David A. Hood, Liam D. Tryon, Heather N. Carter, Yuho Kim, Chris C.W. Chen; Unravelling the mechanisms regulating muscle mitochondrial biogenesis. Biochem J. 2016; 473(15): 2295–2314. doi:10.1042/BCJ20160009.