Garmin, a well-known maker of sports watches, is said to have acquired Moxy Monitor, a company that specializes in measuring muscle oxygen saturation, or SmO2. This information comes from a source close to the deal, though neither company has officially confirmed the acquisition. Moxy Monitor's product is a small sensor that is placed directly on a muscle, usually the thigh, and uses a technology called near-infrared spectroscopy (NIRS) to measure SmO2. This is different from SpO2, which measures oxygen levels in the blood and is typically detected by sensors on wrist devices. The Moxy sensor provides data about the percentage of hemoglobin in the muscle that is carrying oxygen, as well as how that percentage changes over time. This information can help athletes identify when they are reaching a physical limit during exercise or when their muscles have not fully recovered between sets. Garmin has shown interest in muscle-related data for some time, including its Garmin Coach weight training plans and a proprietary algorithm called "Muscle Battery," which is based on SmO2 measurements. Despite Garmin's interest, the Moxy sensor currently needs to be used with a separate device and cannot be built into a Garmin watch. Additionally, the sensor has some known limitations, such as being sensitive to how it is placed on the body and having calibration issues, which have kept it from becoming widely popular. If the acquisition is confirmed, Garmin will need to work on improving the sensor's performance and usability beyond just adding its brand name to the product. This potential acquisition could mark a significant step for Garmin in expanding its offerings beyond traditional fitness tracking. By integrating muscle oxygen monitoring into its product line, Garmin may be aiming to provide more detailed insights into athletic performance and recovery. However, the success of this move will depend on how effectively the company can address the technical challenges associated with the Moxy sensor.