Often neglected when focusing on specific body areas, the heart can be a gauge to set an effective workout. Zone 2, also sometimes called base training, is different from what is traditionally called “cardio” on workout plans but is a great way to build aerobic fitness and increase endurance.
Figuring Out Heart Rate Zones
To start Zone 2 cardio, you’ll need to calculate your unique max heart rate (MHR).
Before you worry about gadgets, there is a simple way to know if you are in Zone 2:
1. To calculate your MHR, Subtract your age from 220 (220 – x = your max heart rate zone). We use Alice, a 40-year-old woman, as an example. Her MHR is 180 beats per minute.
2. Determine Your Heart Rate Zones: Heart rate zones fall in these five zones (we still use Alice to illustrate):
| Zone | % of MHR | Alice’s BPM | What it feels like |
|---|---|---|---|
| Zone 1 | 50 to 60% | 90 to 108 BPM (180 x .5 = 90 or 180 x .6 = 108) | This heart rate is generally used for low-intensity workouts that don’t work your heart or lungs too much, such as a casual walk, easy stretching class, warm-up, or cooldown. |
| Zone 2 | 60 to 70% | 108 to 126 BPM (180 x .6 = 108 or 180 x .7 = 126) | This takes a slight effort that you can sustain for a long time without heavy breathing or taking strain. Your body uses glucose and oxygen in zone 2 to propel itself forward, such as during a long, easy run, a casual bike ride, or an energetic walk. |
| Zone 3 | 70 to 80% | 126 to 144 BPM (180 x .7 = 126 or 180 x .8 = 144) | The upper end of aerobic training and the start of anaerobic training that uses glucose, but not oxygen, for its energy source. It’s achieved by slightly increasing the speed on your bike or upping your running pace to about 70%. |
| Zone 4 | 80 to 90% | 144 to 162 BPM (180 x .8 = 144 or 180 x .9 = 162) | As your body reacts, it starts creating lactate, a by-product of intense exercise. You’re in zone 4 if you’re having trouble breathing and talking in a HIIT class. |
| Zone 5 | 90 to 100% | 162 to 180 BPM (180 x .9 = 162 or 180) | The maximum effort possible. Still, you will likely be unable to maintain it for more than a few minutes. Zone 5 training helps build speed and power. |
What Is Zone 2 Cardio?
Zone 2 cardio is built around heart zone 2. By keeping track of your heart rate, Zone 2 cardio can be a workout at 60 to 70 percent of your unique maximum heart rate. It requires a slow, steady effort that you could maintain for a long time.
Endurance coaches often use a simple intensity split that keeps most training time in Zone 2 or below:
It should make up the majority of weekly workouts, and for endurance athletes, it would be combined with zone 3 training.
Zone 2 cardio, sometimes called low-intensity, steady state (LISS) cardio, helps build a foundation of fitness. It increases aerobic capacity, or the body’s ability to use oxygen efficiently during a workout. In time, workouts will start to feel even easier, and harder workouts will feel less punishing.
Benefits of Zone 2 Cardio Training
- Increased Cardiovascular Fitness
- Quicker Recovery
- Sustainability
- Better Mental Health
- Injury Prevention
Heart rate training can be a high-powered tool, but it’s not infallible. Other factors like sleep quality and quantity, stress levels, body size, emotions, and medications affect BPM, but if your heart rate zones don’t match your felt effort levels, make an appointment with a doctor to help you determine your optimal zones.
Simon Turner is a former Obstacle Workout features writer and writes regularly on sports, fitness and adventure for Probody.
