Monitoring your heart rate is one way to make indoor cycling workouts more efficient. But with so many ways to do this, you’re probably asking, which one should you use: a built-in sensor or an external heart rate monitor?

Generally, external heart rate monitors trump built-in pulse sensors in terms of accuracy and ease of use. Depending on the model or unit, some also include other useful features that increase their value for money.

To learn more about these devices, let’s find out what heart rate monitors are for and whether they’re necessary for your cycling workouts.

What is a Heart Rate Monitor and its Use?

Built-in and external heart rate monitors have the same primary purpose: to measure your pulse or heartbeat per minute.

Using either monitoring device during your cycling workout provides several benefits:

  • It tracks your workout intensity. Zone-based workouts involve adjustments in cycling intensity based on the ideal heart rate. This training style allows you to make pedal strokes effective and prevents you from going too easy.
  • It helps you customise your workouts. Both HIIT cycling and pyramid training involve intervals at varying intensities. And you can easily customise these workouts with a heart rate monitor.
  • It displays your fitness progress. As a beginner, your heart pumps fast at moderate cycling intensities. But over time, you should exert more to boost your heart rate, indicating an improving fitness level. And a heart rate monitor can help you track this development more objectively.
  • It ensures your safety while cycling. Do you have any existing heart health issue that limits your activity? A heart rate sensor can help you stay active at controlled levels per your doctor’s advice. This device can even display irregular heart rhythms so you can address a potential health issue in advance.
Adjusting Bike Resistance for Interval Training

How to Use Built-In and External Heart Rate Monitors

Let’s compare built-in and external heart rate monitors by describing how they work.

Built-in pulse sensors are the metallic plates you see on the handlebar of a spin or upright bike. These sensors are often on the bars below the seat for recumbent bike types.

You grab the handlebar to make the sensor work, wrapping your hands around these metallic plates. Doing this allows the metal to receive electric signals passing through your skin and then translate them into beats per minute.

The sensor will then display its reading on the console or screen of the bike. You can keep your hands in contact with the sensor while cycling or grab them occasionally for periodic monitoring.

On the other hand, external heart rate monitors come in different forms. One type is the chest strap that you wear close to your heart so it can measure your pulse electronically. The strap then transmits the data to a wristwatch receiver, a compatible indoor bike computer, or a fitness app.

Another type is the more popular arm and wrist-worn monitors. These process data like the chest strap, but arm and wrist wearables work through photoplethysmography or PPG.

PPG works when light from the device shines onto the skin (Allen 2007). It then measures your pulse based on how the light reflects off the blood vessels. Pulse-sensing earbuds also use the same technology, only you wear these like earphones.

Differences Between Built-In and External Heart Rate Monitors

Heart rate monitors for exercise bikes come in various forms and sizes. But the most crucial point is their efficacy during your cycling workouts.

Which one is the most accurate or the most comfortable to use? More importantly, which is worth buying? Let’s compare these devices further.

Built-In vs External Heart Rate Monitor

1. Accuracy

Constant contact with the body is the factor that dictates how accurate a heart monitoring device is. This is why the chest strap is the most accurate among the monitoring systems mentioned.

There is minimal movement in the chest area during indoor cycling, making it a better option for this exercise.

Moreover, a Cleveland Clinic article explained that electric devices, like chest straps, have higher accuracy as they directly detect and measure heart activity, not the pulse.

If you prefer an optical-detection device, the earbud type is your next best alternative. Compared with the wrist and arm options, in-ear devices can maintain better body contact for relatively accurate readings.

However, while wrist and arm trackers have inaccuracy issues, user errors, like improper device positioning or wearing (too tight or loose), are likely the cause.

A study by Reddy and colleagues in 2018 concluded that wrist-worn monitors become more inaccurate during high-intensity activity. This is because wrist motion is higher when doing these activities.

As for built-in sensors in exercise bikes, these provide less precise heart rate readings. It’s because proper hand-to-device contact and movement during exercise affect their accuracy.

Built-in sensors are best for people who need periodic monitoring but probably not for those who use heart rate data for athletic training.

Built-In Pulse Sensors on Exercise Bikes

2. Ease of Use and Comfort

The comfort factor is essential when choosing between built-in and external heart rate monitors, given that you’ll be moving and sweating while using them. The arm-worn device is the most user-friendly and comfortable.

With this tracker on your forearm, you’ll experience minimal to no friction while working out. This easy-to-wear device will not dig into your skin during your cycling session or other activities.

Some arm-based trackers also have this colour-changing light feature for specific heart rate zones, which alerts users. They are also easy to reposition or adjust mid-workout.

Wrist-worn trackers are second best when it comes to convenience and comfort. You can even wear them 24/7 for detailed heart rate tracking if needed.

In-ear monitors are also worth considering as long as they come with different tip or wing sizes for a comfortable and secure fit. The least convenient and comfortable devices are probably the built-in sensors and the chest strap monitor.

With built-in trackers, both hands should stay in contact with the metallic sensors. That means you cannot hold a book, use the console, or switch resistance levels if you want continuous heart rate reading.

Other factors like too wet or dry hands and body temperature can also affect built-in sensors, making them extra tricky to use.

As for chest straps, these devices should fit snugly around your sternum area, which can be uncomfortable during long cycling workouts. Substandard chest heart rate straps can also slip or cause chafing. These devices also cannot provide visual alerts or feedback unless connected to a data receiver.

Woman with a Smartwatch

3. Value for Money

Built-in and external heart rate monitors are available in different price categories.

There are higher-end models for the most avid users and entry-level units for others still testing the waters.

However, investing in devices that work even outside your home gym is a better option. Something that is portable and can monitor other workout metrics or has other uses besides heart rate monitoring.

And so, I think wrist-worn trackers offer better value for money. Smartwatches nowadays go beyond heart rate monitoring duty. Best of all, you can wear one even when taking a quick stroll outside or running errands.

In-ear optical monitoring devices take second place. Aside from tracking your heart rate, you can use these as regular earphones. Built-in sensors also offer good value for money if you are happy with a good-quality bike and periodic heart rate tracking.

Chest straps and arm devices are not multipurpose devices. But their value increases when you pair them with a good-priced exercise bike without a built-in sensor. One example is the iFit+ deal for the ProForm Studio Bike Pro 22.


Built-in and external heart rate monitors are valuable indoor exercise bike accessories. With either device, you can enjoy effective, diverse, and safe cycling workouts each time.

After comparing them, we saw that each device has unique qualities that match specific user types. From here, I was able to note three vital conclusions. First, the ideal monitoring device for you depends on your workout.

Specifically, use a chest strap sensor if you move around a lot during exercise or prefer intense workouts. On the other hand, go for other monitoring systems if your routine involves minimal arm, wrist, or hand movements.

Second, if you’re after accurate readings, electrical-based devices are best. And third, consider the option, like a multifunctional tracker, that will give you the most value.

Ultimately, the choice depends on your preference and purpose for using a heart rate monitor. So, which one complements your cycling workouts well?

Check out our top exercise bike picks and see how today’s best models can help you with your performance-tracking needs.

1. Should I invest in an exercise bike with a console?

Getting an indoor bike with a console is ideal, especially if you want to track your workout performance. A console can monitor and display your cycling speed, calorie burn, and other essential cycling metrics. Moreover, some consoles allow you to record multiple user profiles, use built-in workouts, or work with compatible apps. A bike console can be your “healthy distraction” to keep you focused while working out.

2. Is it good to sync to exercise bike fitness apps?

Working out with today’s apps can transport you to real-world routes, let you join virtual races, or enjoy in-studio classes. So, it’s good to sync to these apps to experience diverse and more engaging cycling workouts. The motivation you get from the app can also help you stick to your routine and keep you progressing.