When it comes to fitness, high-intensity workouts are often the go-to for fat-burning and endurance training. Many people assume that faster, harder, and sweatier is always better. But what if slower and steadier could deliver even greater results—especially for fat loss, endurance, and overall health? That’s where Zone 2 cardio comes in.
Largely overlooked in the past, this powerful yet underrated form of cardio is gaining popularity and fast becoming an essential part of any fitness routine. In this article, we dive into the principles behind Zone 2 cardio training, its science-backed benefits, and how to amplify your Zone 2 benefits.
What is Zone 2 Cardio?
So, what exactly is Zone 2 Cardio? The “Zone 2” in Zone 2 cardio refers to the heart rate zone your body reaches when performing a certain physical activity. Zone 2 cardio is the sweet spot of your workout, where your heart rate is at 60-70% of your maximum heart rate, and your body is in the perfect zone for fat-burning and endurance improvement.
There are five different heart rate zones, each burning different components for energy:
Zone 1: Very light-intensity exercise
At this phase, your body is using readily available sources of energy such as glucose, fatty acids, and amino acids. At this level, your heart rate is 50-60% of your maximum heart rate.
Zone 2: Light-intensity exercise with moderate effort
At this level of activity, your readily available sources of energy get depleted, and your body goes after your stored fats. Zone 2 is where fat-burning is at its optimum, and your heart rate is at 60-70% of your maximum.
Zone 3: Moderate-intensity workout
In this zone, your body shifts from fat-burning to carbohydrate-burning because sugars are faster for your body to burn than fats. At this level, your heart rate reaches 70-80% of your max, and your breathing becomes heavier, making conversation more difficult.
Zone 4: High-intensity exercise
When your body is in this phase, you're running completely on carbohydrates, your heart rate is at 80-90% of your max, your breathing is heavy, and talking is very difficult. This level helps improve high-intensity endurance but provides intense strain on the body and is difficult to sustain.
Zone 5: Maximum intensity and “all-out” stage
You can only maintain this stage for a few seconds to a couple of minutes. In this zone, your heart rate is near or at its maximum (90-100%), your breathing is maxed out, and your muscles burn due to high lactate accumulation. Reaching this zone should be in short bursts only and must be followed by proper recovery.
How To Find Your Zone 2 Heart Rate
Because it’s based on the percentage of your maximum heart rate, Zone 2 cardio won’t be the same for everyone. Your maximum heart rate lowers with age, so the intensity of exercise that allows a 20-year-old to reach Zone 2 will be different from that of a 60-year-old. If you don't mind doing math, we'll share the formula to calculate your Zone 2 heart rate range. Or, you can enter your age below and hit calculate to have our Zone 2 heart rate calculator do the math for you!
Here’s the general formula to get your Zone 2 heart rate range:
- Minimum Zone 2 Heart Rate = 0.6 X [208 - (age X 0.7)]
- Maximum Zone 2 Heart Rate = 0.7 X [208 - (age X 0.7)]
For example, if you are 35 years old:
- Minimum Zone 2 Heart Rate = 0.6 X [208 - (35 X 0.7)] = 110.1
- Maximum Zone 2 Heart Rate = 0.7 X [208 - (35 X 0.7)] = 128.5
Hence, your Zone 2 heart rate range is 110 to 128 bpm (beats per minute). Keeping your heart rate within this range keeps your body at the Zone 2 heart rate level.
Calculate Your Zone 2 Heart Rate with Our Zone 2 Heart Rate Calculator
Whatever activity you’re doing, rowing, running, rucking, hiking, etc., you can keep your body in Zone 2 by monitoring your heart rate and staying within this range. Use wearables like a heart rate monitor or smartwatch to track your effort. Alternatively, you can also estimate if you’re in Zone 2 by using the talk test. With this test, it’s pretty simple: You should be able to talk easily without gasping for air when your body is in the Zone 2 range.
Science-Backed Zone 2 Cardio Benefits
Zone 2 training offers a range of science-backed benefits that enhance both health and athletic performance. Understanding these benefits can motivate you to incorporate Zone 2 cardio into your fitness routine.
Fat Burning
Exercising in the Zone 2 level is when your body primarily uses fat as its fuel source, improving your body’s ability to metabolize fat. This adaptation results in metabolic flexibility, allowing you to efficiently use energy during various physical activities.
Improved Mitochondrial Function
The mitochondria are the part of your body’s cells that produce energy. As your body burns more fat in the Zone 2 level, it stimulates the growth of more mitochondria. More mitochondria means more ability to metabolize fats, improved endurance, and prolonged physical activity with reduced fatigue.
Cardiovascular Health
Zone 2 cardio engages the heart muscles with a minimal amount of strain, improving the cardiac output and circulation. Over time, this can contribute to lower blood pressure and a reduced risk of heart disease.
Blood Sugar Regulation
Zone 2 training has been shown to help in blood sugar regulation with its role in improving insulin sensitivity. People with low insulin sensitivity are prone to Type II diabetes and other metabolic disorders.
Effective Endurance Training
Unlike high-intensity workouts, Zone 2 cardio lets you train for longer and more frequent sessions with shorter periods of recovery. Thus, you can sustain a more consistent endurance development without the heightened risk of injury or burnout.
Lactate Clearance
Zone 2 training plays a crucial role in improving lactate clearance, which is essential for endurance and overall athletic performance. During exercise, your muscles produce lactate as a byproduct of energy production. In Zone 2, your body operates at an intensity that allows it to efficiently clear lactate from the bloodstream, preventing its accumulation and delaying fatigue. This adaptation enhances your ability to sustain higher intensities for longer periods, making it a key component of endurance training and overall metabolic efficiency.
How to Add Zone 2 Cardio to Your Training
1. Choose Your Exercise
The type of exercise for your Zone 2 cardio can make or break your results. Your exercise would be low to moderate intensity, meaning it should be sustainable for 30 minutes or more. Some of the great Zone 2 activities include brisk walking, cycling, rowing, swimming, treadmill walking, and jogging. Whatever you do, avoid going too hard—if you're breathing too heavily to talk, you're likely out of Zone 2.
2. Dial in the Duration and Frequency
Zone 2 cardio training works best when done for longer durations. Beginners can start at 30 minutes per session, and it’s not advisable to go beyond 90 minutes per session. Do Zone 2 cardio at least 3 times per week for optimal results. Start with shorter sessions and increase gradually as your endurance improves.
3. Don’t Forget About Nutrition and Hydration
Your diet plays a crucial role in optimizing the results of Zone 2 training. It should include healthy fats, lean proteins, and complex carbohydrates. Avoid sugary foods because high blood sugar during training can interfere with the fat-burning process. Drink water before, during, and after your workout. Also, make sure you replenish your electrolytes if you are training for more than 60 minutes.
4. Track Your Progress
Knowing you’re making progress not only motivates you but also helps you get the most out of your training and improves your exercise plan. Here are the key data you should be tracking:
- Heart rate - should stay at 60-70% of your maximum heart rate.
- Duration of training - should increase over time.
- Perceived effort - should feel easy to moderate.
- Recovery time - should improve over time.
A fitness app or smartwatch can help you monitor your progress over weeks and months.
5. Remember that Results Take Time
Be patient. Like other healthy and realistic exercise plans, Zone 2 cardio does not show results overnight. Zone 2 cardio is a long-term investment in endurance, metabolism, and heart health. Stay consistent and trust the process—Zone 2 training rewards patience!
How to Amplify Your Zone 2 Cardio Benefits
Want to take your Zone 2 training to the next level? Add a fractional weighted vest from Aion. Adding this vest allows you to reach Zone 2 faster and stay there longer, amplifying your results in the optimal fat-burning and endurance-building zone.
In fact, a study led by experts using data from the WHOOP Wearable Band found that wearing the Aion vest while walking more than doubled time spent in Zone 2! Participants in the walking test spent 56% of their walk in Zone 2 while wearing an Aion vest, compared to only 26% of time spent in Zone 2 when walking without an Aion vest.
Here’s how:
- Enhances caloric burn - Aion adds resistance that increases the body’s energy expenditure while staying in Zone 2.
- Builds strength and endurance - Aion improves these simultaneously by engaging the muscles without added strain.
- Improves posture and core stability - Aion lets you train with better alignment and balance through even weight distribution and compression.
- Maintains comfort and movability - Aion’s patent-pending technology and ergonomic design ensure a snug yet non-restrictive fit.
The renowned human biologist, biohacker, and longevity expert Gary Brecka had this to say about his Aion vest, “This has become my new love, my new joy, my new biohacking hack of all time for exercise. If you’re walking, by adding weight, you actually activate more muscles, you increase the intensity of your workout without increasing the duration of your workout. So you spend the same time doing more with less. You can improve your metabolism. You can increase the intensity of that basic exercise. Keep your heart rate high. Stay in Zone 2 a lot longer. And you will not even notice that you’re wearing the weight.”
Whatever Zone 2 cardio you do, Aion is the perfect tool to maximize your gains without compromising performance. Amplify your Zone 2 training today with Aion and start seeing faster, stronger results!
“The Aion vest has become my new love, my new joy, my new biohacking hack of all time for exercise."
- Gary Brecka
