SET OF 4: Train.Red FYER Sensor - Image
Train.Red FYER Sensor
Train.Red FYER Sensor
Train.Red FYER Sensor
Train.Red FYER Sensor

SET OF 4: Train.Red FYER Sensor

Regular price €2.996,00 Sale price€2.846,20
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Set of 4 Train.Red FYER Sensors. The FYER is the smallest and most innovative wearable muscle oxygen sensor in the world. To improve your performance, you invest time and energy in equipment, standardized training programs, supplements, etc., but often we forget the one thing that drives our performance: our muscles.


Our FYER muscle oxygen sensor comes with: the Train.Red FYER, a charging cable, one Patch Pack (20 patches), and one Strap Pack (S-M-L) all in a durable travel-pouch.

    Train.Red tracks your muscle oxygen in real time with sensors. Our smart app translates this muscle data into key features to guide athletes to improve their performance.


    - Size: 1.2 x 4.4x 5.9 (cm) / .5 x 1.7 x 2.3 (in)
    - Weight: 20 grams
    - Measure-depth: up to 20mm in your muscle
    - Light source & detector distance: up to 35mm
    - Sweat-proof: Yes
    - Battery: up to 24 hours during active use
    - Speed: 10Hz
    - Connectivity: BLE and ANT+
    - Materials: high-quality biocompatible ABS and TPE app

    Works best with our Train.Red app. Currently available for Android users. For iOS users we collaborate with VO2 Master (see connectivity). We're working hard on our own Train.Red iOS app providing all data and functionality, we expect to officially release iOS Q4 this year.


    Compatible with: V02Master Manager, Splendo Health & Fit, ANT+ profile like Garmin, Wahoo, etc. As well as Garmin data field

    Train.Red shines a light on your performance based on light technology, the FYER looks inside your muscles with Near InfraRed Spectroscopy (NIRS). The sensor translates the oxygen saturation and (de-)oxyhemoglobin changes in your muscle tissue into real-time key features with the help of artificial intelligence and a friendly user interface.

    Our partner Artinis Medical Systems has over 1500 publications, read more publications


    Gain strength and/or endurance by using the data from your muscles.

    • SmO2%, Muscle Oxygen or Tissue Saturation, is the amount of oxygen in your muscle tissue (%). Adjust your pace in real-time or analyze afterward
    • Determine if your muscle is working hard, or hardly working. 5 muscle states are visualized in real-time. Stay in the green state during easy sessions, or go in the red during efforts. Learn more
    • High-performance coach or hobby scientist? Measure the Oxy-, and DeOxyhemoglobin concentration changes, or use the total hemoglobin and hemoglobin difference to your advantage.