Apple’s new earbuds generate heart rate insights and the potential for on-device smarts, but if you care about dependable workout data, a smartwatch is the way to go. For all the advances, ear-based tracking remains weak in the area where heel-based tracking is strongest: consistency under real-world exercising conditions. Music goes in your ears; fitness information goes on your wrist.
Ear sensors seem smart, but physics push back
Earbuds use optical photoplethysmography (PPG), in which light is (non-invasively) beamed through tissue and the subsequent blood-volume changes are measured. In the ear, that signal can be easily disturbed by jaw movement, a less-than-perfect fit, sweat and the simple act of twisting a bud mid-run. The end result can be dropouts, lag, and spikes that can ruin interval training data.
Even the ear-based HR can vary wildly, as was evident already from independent testers. DC Rainmaker noted regular dropouts and spotty readings from earbud trackers during hard efforts, and Quantified Scientist saw similarly mixed results in a lab setting. That divide underscores the heart of the issue: individual ear anatomy and fit are significant factors in how every run can impact a user, and that is not a sound basis for reliable training.
Applying artificial intelligence on top of a noisy signal isn’t going to completely solve motion artifact. Calorie estimates, heart rate zones, coaching cues, they all inherit that noise if the input optical signal is unstable. Simply put, slick features are nothing without the sensor that makes it all possible.
Why watches continue to win workouts
Todays sports watches and mainstream wearables all offer secure, repeatable positioning combined with larger sensor arrays, and finely tuned algorithms. The Apple Watch has also been well validated for heart rate accuracy in steady-state efforts, while Garmin’s newest Elevate sensors (including those on the FR245), Polar’s Precision Prime, and Fitbit’s optically based multi-path PPG has all got better in high-motion scenarios.
Crucially, the watches incorporate more than a pulse. You also have GPS for pace and distance, barometers for elevation, skin temperature trends and recovery metrics like HRV-based readiness. That multi-sensor fusion provides context that earbuds can’t deliver, from training load to VO2 max estimates and cadence guidance.
For when precision counts—during sprints, hill repeats, cycling intervals—a chest strap is still the gold standard, and watches connect to them instantaneously. For many of those athletes, it’s a simple stack: watch for brain and GPS, chest strap for heart rate, earbuds for music or podcast audio. It’s a proven, low-friction setup.
Accuracy is not a nice-to-have; it determines outcomes
Training by zone is based on exact heart rate. If you err on the side of 10–15 bpm, you may find yourself running an endurance run as a tempo run or undercooking a threshold run. The American College of Sports Medicine focuses on controlling intensity to be properly progressed for prevention of injury and bad data undermines both.
Estimates of calorie burn are even more slippery. A Stanford Medicine review of wearables discovered relatively accurate heart rate tracking while calorie counts frequently varied. If earbuds are magically inventing calories out of jittery pulse data and accelerometer WAG s, your fueling and recovery are going to be off.
There’s a health angle, too. Wrist devices with validated algorithms have detected arrhythmias and abnormal trends in large studies, alerting high-risk patients to seek care. Earbuds are not put in or engineered or validated for that sort of longitudinal tracking.
What Apple’s earbuds can do — and where they fall
Apple’s pitch combines infrared sensing with on-device models for estimating calories and tracking dozens of types of workouts, plus a coaching layer that responds to your history. In the ecosystem, those perks are seamless, and to occasional movers, they might be “good enough.”
The caveat is the reliance on ear-Generated heart rate. If your size is the perfect fit and your workouts are regular, the results may appear fine. Begin to sweat, throw in some intervals or step on a bumpy ride and the potential for noise intrudes. It’s that kind of fragility that makes a watch a safer anchor for fitness data in the first place.
For the serious and casual athlete, the logical arrangement
For consistent tracking: wear a smartwatch, pair a chest strap on high-intensity days and wear earbuds for sound and cues only. This layout ensures that your metrics are steady, your music is consistent, and you’re being coached well.
If you’re casual: a watch is its own sweet spot — low effort, high reliability, and robust ecosystem support from services like Apple Fitness, Garmin Connect, Polar Flow, and Google Fit.
You’ll receive trends, benchmarks and actionable insights that earbuds alone can’t deliver.
Bottom line
New heart-rate-reading earbuds are an interesting bonus, not a full-on tracker replacement. For dependable fitness, the smartwatch is the one to keep — just don’t forget the AirPods for that soundtrack.