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.

FYER SPECIFICATIONS
- 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
Connect your fyer
Train.Red APP: available on Android devices and in the near future iOS devices (development not completed)In app exporting: unfiltered data to .Fit file or .CSV
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.
Scientifically proven by our partner Artinis medical systems, with over 1500 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.


In Real-time
- Muscle Oxygen: SMO2 percentage and graph (per sensor)
- Muscle States: 5 intensity zones of your muscles
- Pacing: pace yourself with Time In Muscle States feature
- Smart Rest: optimal rest for endurance, hypertrophy and strength
- Muscle Stress Score: amount of muscle stress during your session
the data explained
- SMO2% / TSI%: the percentage of oxygen in your muscle
- 02Hb changes: blood with oxygen (oxyhemoglobin)
- HHb changes: blood without oxygen (deoxyhemoglobin)
- tHb: blood oxygen transport capacity (total hemoglobin)
- HbDiff: the difference between 02Hb and HHb