A Simple Guide to Training with Heart Rate Zones

Learn how to use your max heart rate to determine your heart rate zones and optimize the effectiveness of your workouts.

What is Heart rate training?

Simply put, heart rate training consists of using your heart rate to gauge your exercise intensity, and aiming for different heart rate zones depending on what your fitness goals are. By targeting specific heart rate zones, you can tailor your workouts to meet your unique goals, whether you're looking to improve endurance, boost VO₂ Max, or support longevity. This approach ensures you're working at the right intensity to achieve your goals efficiently and effectively.

Finding your heart rate zones

Strain is a function of your max heart rate and the amount of time you spend in different heart rate (HR) zones, the more time spent in elevated heart rates, the higher your Strain. WHOOP uses the heart rate reserve method, which takes into account your max heart rate and resting heart rate over the last 14 recoveries to give you more accurate and personalized HR zones, so as you make progress your HR zones will reflect that. 

You can also manually adjust your HR zones to further personalize your experience.

To adjust your max HR & HR zones: Tap More > App Settings > Activity Settings > Heart Rate Settings

Calculating Max Heart Rate

The first step to heart rate training is to calculate your max heart rate. A basic formula that is commonly used is to subtract your age from 220. With this method, a 30 year old’s max heart rate would be 190 beats per minute. However, this equation does not take into account things specific to you, like biological sex, genetics, etc. Over the years, a number of more detailed formulas have been created, such as the Tanaka (208 - 0.7 x age) or the Gulati (206 - 0.88 x age, for women only) method, but they make broad generalizations as well and fall victim to many of the same variables. Additionally, other factors like temperature, altitude, hydration, and even time of day can affect your heart rate. Every human body is different with varying maximum heart rates, so a better solution is to use a wrist-worn heart rate monitor like WHOOP that will determine your personal max heart rate.

What Are Heart Rate Training Zones?

Once you know your max heart rate, you can establish your own heart rate training zones. Below is a graphic listing the various heart rate zones and what you can accomplish by training in each. For example, if you’re exercising and your heart rate is at 40-60% of your Heart Rate Reserve, your workout is ideal for warm ups and cool downs, or active recovery.

Burning Fatty Acids

Weight loss is a common goal for many of us, and people often wonder which zone is best for burning fatty acids. While training at zone 2 technically burns more fatty acids than more intense exercise (when your body shifts to burning more carbohydrates instead), losing weight is actually about being in a caloric deficit. You can sustain activity longer at a lower heart rate, but you’ll burn more calories per minute when you increase your exertion. There’s no reason to avoid training at a higher or lower heart rate range if you’re trying to lose weight - it all comes down to energy balance. Learn More: The Truth About the Fat Burning Heart Rate Zone

Aerobic Heart Rate Zone vs Anaerobic

Aerobic exercise is when your body is able to take in enough oxygen to sustain how physically active you are without dipping into another energy source. Working out in zones 1-3 (moderate intensity) will improve your aerobic fitness level. This will allow you to build endurance and create lean muscle for things like distance running or cycling. It’s also good for your overall cardiac health. Anaerobic exercise (“the absence of oxygen”) causes your muscles to need more energy than is provided by the oxygen you are breathing in, so they begin to break down sugars and produce lactate. Exercise at top end zone 3, but in particular zones 4-5 (vigorous intensity) will increase your lactate threshold. These heart rate zones are often useful to improve athletic performance   and power output in non-endurance based events. Learn More: What is the Aerobic Heart Rate Zone and How Do You Target it?

Benefits of Heart Rate Training

As a general rule, most athletes train in varying zones of max heart rate at different times, both within specific workouts and from one to the next. A typical one-hour aerobic session might include 10 minutes in zone 1 to warm up and cool down and 40 minutes at a sustainable pace in zones 2-3. A typical anaerobic workout might include 10 minutes in zone 1 to warm up and cool down, followed by 4 rounds of 4 minutes of hard effort, ideally in zones 4-5. Monitoring your workout heart rate can help you avoid training too hard by knowing exactly when you’re overexerting yourself. It will also allow you to bounce back faster by ensuring you stay in the proper zone on recovery days. Additionally, heart rate training enables you to moderate external factors like heat and humidity, or better adjust on days when you may not be fully recovered. In these cases, your standard workout may be increasing your heart rate more than usual. Learn More: Running Heart Rate Zones

Know Your Heart Rate Zones in Real Time with WHOOP

WHOOP measures your heart rate 24/7 and quantifies the strain your body takes on each day. Every morning, our recovery metric (calculated using heart rate variability, resting heart rate, respiratory rate and sleep) tells you how prepared your body is to take on strain. When you enable live activities with WHOOP, you can easily see in real time which heart rate zone you’re in via a widget on your lock screen, so you’ll know exactly when to dial it back, or kick it up a notch. You can also retroactively view the time you spent in each heart rate zone by tapping into your Activity. WHOOP will show you a detailed breakdown of time in each zone so you can further optimize your training.

To get started, press the action button (+) → start activity → and lock your phone. Currently this feature is only available on iPhone.