Heart rate zones and how to use them to maximize your fitness - chof 360 news

Forget the guesswork — fitness just got easier to master. As fitness trackers grow in popularity alongside workouts that use the devices like Orangetheory Fitness and Peloton's Power Zone program, you now have easy access to biometrics, like heart rate zones, that can guide smarter workouts and give you an edge to hit your goals.

Heart rate zones are a tool that help you gauge how hard your body is working during exercise by breaking down your maximum heart rate into specific intensity levels, explains Dr. Steven Stache Jr., chief of Rothman Orthopaedic Institute's non-operative sports medicine division, Philadelphia Phillies team physician and chief medical officer at Drexel University Athletics. Think of these zones as ranges that show how fast your heart beats per minute, with each range corresponding to a different effort level — from light activity, like a leisurely walk, to all-out sprints at maximum effort.

These zones are more than just numbers — they're a road map to more intelligent training. "Each zone can be used to optimize exercise with a purpose, such as burning fat, improving endurance or boosting speed. In essence, using heart rate zones is like applying 'speed limits' for your heart during exercise," he continues. You can train precisely and see better results by tailoring your intensity to your goals.

Here's what to know about heart rate zones, how to use them to train effectively and how to get started, with or without a tracking device.

What are heart rate zones?

Heart rate zones measure how hard your heart works during exercise by dividing your effort into intensity levels. The five levels are calculated as percentages of your maximum heart rate, which is the highest number of beats per minute your heart can safely manage.

According to personal trainer Tara De Leon, each zone offers distinct health and performance benefits. Here's an overview:

How to calculate your heart rate zones

Using the Karvonen formula is the most common way to calculate heart rate zones. At a glance, this formula looks complicated:

([maximum heart rate - resting heart] x % intensity) + resting heart rate = training zone

However, it's easier than you might think when broken into steps. Here's how it works:

Find your maximum heart rate (MHR)

The simplest way to estimate your MHR is by subtracting your age from 220. For example, if you're 45, your estimated MHR would be 175 (220 - 45 = 175).

For a slightly more accurate estimate, you can use the Tanaka Method, calculated as 208 - (0.7 x age). Using the same example, a 45-year-old's MHR would be 176.5 (208 - (0.7 x 45) = 176.5). This method is often used by fitness programs like Orangetheory Fitness, according to their vice president of fitness, Scott Brown.

Determine your resting heart rate (RHR)

Your RHR is how often your heart beats per minute when you're completely at rest. For most adults, this falls between 60 to 100 BPM (endurance athletes may have a lower RHR). You can measure it using a fitness tracker or by counting the pulse at your wrist while sitting still.

Calculate your heart rate reserve (HRR)

HRR is the difference between your maximum and resting heart rates. For example, if your MHR is 175 and your RHR is 65, your HRR would be 110 (175 - 65 = 110).

Find your target heart rate zones

Use your HRR to finalize your Karvonen formula calculations and find your target heart rate for each zone. Simply multiply your HRR by the percentage of maximum effort each zone represents, then add your RHR. You can use these zone percentages to make the calculations:

Using the example HRR of 110 calculated above, your Zone 2 target would be (110 x 0.6) + RHR (65) = 131 BPM.

Alternative methods

You can informally observe perceived exertion if you want to skip the math. If you can easily hold a conversation, you're likely in Zones 1 or 2, but if talking is more challenging, you're likely in Zones 3 or 4. And if you're working so hard you can't talk at all? You're certainly in Zone 5.

While these methods provide helpful estimates, the most precise way to determine your heart rate zones is through a VO2 max test conducted by a cardiologist or exercise physiologist. These tests are often performed in hospitals, sports performance labs or universities.

Using heart rate zones in your workouts

Understanding your heart rate zones can eliminate the guesswork associated with exercise. It allows you to measure your effort and train intentionally to achieve your goals.

"Instead of guessing how hard you should push yourself, you monitor your heart rate and adjust your effort to stay within a specific range. This approach can help you meet your fitness goals, whether that's building stamina, burning calories or improving overall performance," says Stache. "Heart rate zone training ensures you're exercising at the right intensity for your goals, so you don't waste time doing too much or too little."

Using a fitness tracker, you can monitor your real-time heart rate during workouts to identify your zone and make sure you're reaping the benefits tailored to your goals:

While Zone 1 is best for warming up and cooling down, how much time you spend in other zones depends on your fitness goals and level:

Brown highlights the importance of training across all five zones: "Your body uses two key energy sources. By training in all zones, you help your body adapt to using both efficiently, ensuring metabolic flexibility."

Ease the guesswork and invest in a fitness tracker

Fitness trackers are invaluable for monitoring your heart rate and tracking the time spent in various heart-rate zones. We tested 18 popular models to find the best options, and you can learn about our findings here. If you're looking to start heart-rate training, here are a few of our favorite models.

Garmin

Battery life: Up to 10 days | Metrics tracked: Activities (calories burned, time, distance, steps, sets), sleep, energy, heart rate, skin temperature, HRV, menstrual cycles/health, stress, blood oxygen saturation, respiration, VO2 max | Smart tracker: Yes | GPS functionality: Yes | Special features: Send/receive calls, GPS tracking for indoor and outdoor sports/activities, music storage, ECG capabilities, wheelchair mode, waterproof, workout plans or build your own workout capabilities

Garmin's Venu 3S lives up to the brand's stellar reputation for durability, precise tracking and impressive battery life, while also excelling in its ability to monitor workouts across various sports and disciplines. 

This model takes things a step further by offering advanced health features like detailed insights, ECG sensors and atrial fibrillation detection. It also includes music storage, smartphone notifications compatible with both iOS and Android, a built-in microphone and speaker and a wheelchair-friendly mode, making it one of the most versatile fitness watches on the market.

$445 at Amazon

Fitbit

Battery life: Up to seven days | Metrics tracked: Steps, heart rate, calories burned, distance, sleep, stress, blood oxygenation | Smart tracker: Yes | GPS functionality: Yes | Special features: Connects to exercise machines, VO2 max tracking, sleep score tracking, call, text and calendar notifications, SmartWake alarm, equipped with Google Maps, Google Wallet and YouTube Music, water resistance up to 50 meters

If you’re new to fitness trackers and want a simple way to log workouts, track steps and monitor your heart rate without being overwhelmed by extra features, the Fitbit Charge 6 is an excellent choice. Lightweight, comfortable and easy to use, this device offers all the essentials at a budget-friendly price, making it perfect for beginners.

$125 at Walmart

Polar

Battery life: Up to 30 hours | Metrics tracked: Heart rate | Smart tracker: No | GPS functionality: No | Special features: Can be worn with an armband or clipped to goggles, waterproof up to 50 meters, Bluetooth and ANT+ connectivity

If you’re looking for a no-frills fitness tracker that focuses on monitoring your heart rate and workout intensity, the Polar Verity might be your perfect match. This compact device — about the size of a coin — offers versatility and simplicity, fitting into an armband or goggle clip for easy wear during exercise.

The device offers three versatile modes to match your needs. In heart rate mode, you can sync it with Bluetooth or ANT+ to monitor your heart rate in real-time during your workout. Recording mode allows you to exercise without needing your phone or watch nearby, capturing your heart rate data throughout the session so you can sync it later. Similarly, swimming mode tracks the intensity of your swim workouts and lets you sync the data after you’re out of the pool.

The Polar Verity is lightweight and efficient and helps you keep your fitness tracking simple yet effective.

$100 at Amazon

Factors affecting heart rate

Heart rate is a valuable metric, but it's not the only information you should hang your hat on. "Heart rate isn't a perfect measurement. It can be influenced by environmental factors like humidity and temperature, stimulants, pharmaceuticals, sleep and stress," says Brown.

Additional factors such as age, fitness level and hydration also play a role in how your heart rate responds during activity. "With all that said, it's still one of the easiest and most accessible biometrics to tap into. It offers insight into your body that moves beyond just perception," Brown adds.

If you want to use heart rate training to maximize your workouts, it's important to also pay attention to how your body feels and how intensely you feel you're working. Hard data paired with personal perception can help guide your workouts and ensure you're getting the most out of every minute spent sweating.

FAQs

What is the best heart rate zone for weight loss?

Training in zones 1 through 3 burn fat at a higher percentage than carbohydrates, so individuals with weight loss goals may want to spend most of their training time here. De Leon also encourages interval training.

"You burn a large percentage of fat in Zone 2, but you're not burning a huge amount of calories overall. If you bump it up to zones 3 or 4, you won't burn as big of a percentage of fat, but because of the increased calorie burn, you'll burn more fat overall. This is one of the reasons interval training is so popular."

How accurate are heart rate monitors?

Fitness trackers aren't medical-grade devices, so their readings may not always be 100% accurate. However, research consistently shows that chest strap monitors provide the most reliable and precise data compared to other trackers.

What should I do if I can't reach my target heart rate zone?

If your heart rate is below your target zone, try increasing the intensity of your workout by picking up the pace or adding hills and intervals. If it's too high, slow down, remove intervals or take extra rest breaks.

If you're consistently unable to stay within your target zone, consider consulting your physician or other healthcare professional to rule out any underlying medical concerns affecting your heart rate.

Is it safe to train in the maximum heart rate zone?

If you've been medically cleared for high-intensity exercise, training in Zone 5 is generally safe — but only for short bursts of up to a few minutes at a time. Also, listen to your body and stop if you experience pain or discomfort. You may also want to work with a trainer or coach if you're new to more intense exercise sessions to ensure you're not pushing yourself too hard based on your current fitness level.

How often should I check my heart rate during a workout?

Monitoring your heart rate during a workout is a great way to gauge how your body responds. However, if constant checking feels distracting or affects your form, pay attention to your body's natural cues instead. These can serve as an effective feedback loop to keep your intensity in check without compromising your workout.

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Our health content is for informational purposes only and is not intended as professional medical advice. Consult a medical professional on questions about your health.