Garmin May Be Working on a Muscle Oxygen Sensor for Smarter Strength Training
Smartwatches have become powerful tools for runners, cyclists, triathletes, and other endurance athletes. With built-in GNSS tracking, wrist-based heart rate sensors, speed estimates, distance measurements, and even running power data, modern wearables can deliver a detailed picture of outdoor performance.
For strength training, however, the story is different.
A smartwatch can count reps, estimate workout duration, and monitor heart rate, but it still cannot directly measure how much weight you lift or how hard a specific muscle is working. Heart rate is also not always the best indicator during resistance training, since heavy sets, short rest periods, and localized muscle fatigue do not always produce the same cardiovascular response as endurance exercise.
That could change if Garmin’s latest software clues point to a new type of fitness sensor focused on muscle performance.
Recent findings inside the Garmin Connect app suggest that Garmin may be preparing support for muscle oxygen monitoring. The app reportedly includes data fields for average, minimum, and maximum oxygen-saturated hemoglobin, along with total hemoglobin concentration. These are the types of metrics commonly associated with tracking oxygen availability inside working muscles.
Muscle oxygen saturation is especially useful because it can show how much oxygen is available in a specific muscle during exercise. When oxygen saturation drops, it often indicates that the muscle is becoming fatigued and struggling to maintain output. For athletes, this could provide valuable feedback during strength sessions, interval workouts, cycling efforts, or rehabilitation training.
Unlike standard blood oxygen monitoring, which measures overall oxygen saturation in the body, muscle oxygen tracking is localized. That means the sensor must be placed close to the muscle being trained. For example, an athlete might place it on the quadriceps during leg extensions, on the chest during bench presses, or on the calf during running drills.
This kind of data could make strength training far more precise. Instead of relying only on perceived effort or heart rate, users could see when a muscle is ready for another set, when it needs more recovery, or when fatigue is building too quickly. It could also help athletes compare left and right muscle performance, fine-tune rest periods, and better understand how different workouts affect specific muscle groups.
For endurance athletes, muscle oxygen data may also offer performance benefits. Runners and cyclists could use it to monitor fatigue during high-intensity intervals, tempo sessions, or long efforts. If a muscle’s oxygen levels drop sharply and fail to recover, it may signal that the athlete is pushing beyond a sustainable pace.
At this stage, it is still unclear what Garmin’s final hardware could look like. The company may introduce a standalone sensor, an accessory that pairs with its watches, or another wearable format designed to attach directly to the body. Since muscle oxygen monitoring requires placement on the target area, it would likely need to be more flexible than a traditional wrist-based smartwatch sensor.
If Garmin does launch this feature, it could be a major step forward for sports wearables. Strength athletes have long lacked the same level of real-time performance data that endurance athletes enjoy. A dedicated muscle oxygen sensor could help bridge that gap by making gym workouts more measurable, personalized, and science-driven.
For now, the feature appears to be in development rather than officially announced. Still, the presence of muscle oxygen data fields in Garmin Connect suggests that the company is exploring new ways to expand beyond heart rate, GPS, sleep tracking, and general wellness metrics.
If released, Garmin’s muscle oxygen tracking could become one of the most interesting fitness technology upgrades for athletes who want deeper insight into fatigue, recovery, and training intensity.
