Wearable Tech in Sports: An Olympian’s Perspective on Accuracy, Performance, and Everyday Use
By Mathilda Hodgkins-Byrne OLY, ConsultaChem editor
About the Author: Mathilda Hodgkins-Byrne
Mathilda Hodgkins-Byrne is a British Olympic rower, Paris 2024 bronze medalist in the Women’s Double Sculls, and an editor at ConsultaChem, specializing in physiological health scientific writing. With years of experience at the elite level, she has firsthand insight into how wearable technology enhances athletic performance, training, and recovery. Mathilda is passionate about combining sports science and data-driven training to optimize performance and help athletes get the most out of their wearable tech.
The Evolution of Wearable Tech for Athletes
The first patent for a wireless heart rate (HR) monitor was filed in 1977 by Polar Electro, when a battery-operated monitor was developed to aid the Finnish National Cross Country Ski Team’s training. Following this invention, the world’s first wireless HR rate monitor was released in 1982, and in 1986 the first HR analysis software was developed. Initially, this technology was adopted by elite athletes, such as the U.S. cycling team at the Los Angeles Olympic Games in 1984, and was only used during training. However, wearable HR monitors quickly became part of everyday wear, giving insights into an athlete’s physiology, training and potential performance as well as recovery, which, at the time, was a significant innovation.
How Accurate is Wearable Tech for Exercise?
Today’s sports wearables go beyond HR monitoring. GPS trackers, blood pressure monitors, light-therapy pain relief gadgets and smart-goggles are widely available. However, many highly-specialised devices only track a single metric or have a specific use - swimming goggles aren’t practical for all-day wear!
In the race to address demand for gadgets to aid training and exercise for the mass market, as well as elite athletes, watches have emerged as a useful item that can be readily adapted to be multi-functional, with a HR monitor now fairly standard. And it’s not just HR that can be measured: strain and recovery, sleep cycles and quality, as well as temperature and calories are commonly included as key features.
Mathilda Hodgkins-Byrne and Becky Wilder competing in the Women’s Double Sculls at the Paris 2024 Olympics, where they secured a bronze medal.
How Do Heart Rate Monitors Work?
Most wearable wristwatches and fitness trackers measure heart rate using two key technologies:
Electrocardiography (ECG): Used in chest-band wearables, ECG measures the heart’s electrical signals.
Photoplethysmography (PPG): Found in wrist, hand, and forearm wearables, PPG uses LEDs and sensors in contact with the skin to detect expansion of the blood vessels.
Which is more accurate? ECG chest bands typically provide more precise HR readings than wrist-based devices, which can be affected by motion artefacts and improper fit, but the quality of the algorithm being used is also important.
Wearable Tech for Performance: How Athletes Use Data to Improve Training
In recent years, wearable gadgets have naturally split into two separate categories: wearables that provide heart rate data and must be worn in contact with the skin, and wearables that provide other metrics, such as running cadence or wattage output, and do not require skin contact. These are often mounted onto sports equipment. Furthermore, some wearables have the option of a screen that can provide instantaneous feedback (such as a Garmin watch), whereas others, such as the WHOOP or Aktiia, require the data to be accessed retroactively, usually through an app on a smartphone.
Technology now plays a key role in elite sports, from rowing to cycling to running but, regardless of when you access the data or how it is collected, real-time performance tracking is provided, helping athletes fine-tune their training. For example:
Cyclists often use power meters to measure wattage output and exertion levels.
Rowers utilize biomechanical analysis (biomech), which tracks force curves, blade slippage, and stroke efficiency.
Runners undergo gait analysis, which helps identify optimal running shoes and injury risks.
Tracking data over time allows athletes to identify performance trends. However, context matters - data collected under varying weather conditions or fatigue levels can be misleading if not interpreted correctly. For sports completed outside the use of equipment-mounted tach is particularly important as it enables accurate comparison between sessions and removes the variability of weather conditions on outputs, for example speed, which is important for consistent training (and sometimes for maintaining morale).
Can Wearable Tech Give Too Much Data? When to Trust (or Ignore) Your Metrics
With so much data at our fingertips, how much is too much? While HR, exertion, and recovery metrics provide valuable insights, over-reliance on them can lead to misinterpretation and unnecessary concern.
The Context Problem: When Data Misleads
Consider this scenario: At a pre-World Championships training camp in Italy, one of my teammates trained in extreme heat for the first time. Her HR skyrocketed, triggering her smartwatch to recommend rest. However, our team physiologist explained that this was simply heat stress, not a sign of poor recovery. Without expert interpretation, she might have stopped training unnecessarily.
Or this: my sister sends her HR data to her cycling coach daily. During one period, her coach was able to see her heart rate wasn’t behaving as it should in the training sessions. In this instance, it turned out that my sister was over-training and needed encouragement to dial her training back.
And here’s the important part: sometimes we can push ourselves beyond sensible limits and it’s therefore essential that when interpreting data we remain objective and listen to our bodies, adjusting training load as necessary.
Is a screen necessary?
While we are used to screens providing ready, regular access to information, using a device without a screen could be beneficial for allowing users to decide when to engage with data; users can train using RPE (rate of perceived exertion) and consider data retrospectively. Use of RPE might also help avoid injury, as users train to their ability or how they’re feeling rather than to meet or exceed certain metrics (akin to Jeffing in the running world). But it’s all down to personal preference.
Choosing the Right Wearable Tech: Factors to Consider
If you’re looking for the best wearable fitness tracker, consider these key factors:
Accuracy: Chest straps (ECG) are typically more reliable than wrist-based sensors (PPG).
Battery Life: Essential for endurance sports and long-term health tracking.
Functionality: Some devices, like Garmin and WHOOP, provide instant feedback, while others such as the OURA ring require app syncing.
Medical Validation: Devices like Aktiia’s blood pressure monitor are clinically approved in Europe, whereas most consumer wearables are not.
Final Thoughts: The Balance Between Data and Intuition
While wearable tech can enhance training and health tracking, the ultimate decision-maker is you. Data should inform - not dictate - your fitness routine. If in doubt, listen to your body first, and let wearables supplement your intuition.
What’s Your Experience?
Do you use wearable tech in your training? Share your thoughts in the comments!