
Best Train Red Discount 2025 – Up to 30% Off (Cyber Monday Live)
★ The absolute best Train.Red discount right now is 30% off the full course ★
10% off 1 sensor • 15% off multiple sensors • 30% off full course
Ends Dec 1 – discount auto-applied at checkout
FYER 2.0 + App
€562.50 (10% off €625)
Most popular muscle oxygen sensor
Buy Now – 10% Off
Train.Red PLUS + App
From €1,296.25 (15% off €1,525)
Advanced multi-sensor system
Buy Now – 15% Off
Full Train.Red Course
30% OFF – BEST DISCOUNT
Complete SmO2% training education
Get Course – 30% Off
Train.Red FYER & PLUS are the most accurate consumer muscle oxygen (SmO2%) sensors available. Used daily by pros and serious athletes for warm-up optimisation, threshold testing, and recovery monitoring.
→ Shop All Train.Red Deals – Best Discounts Live
Offer ends Dec 1, 2025 • Prices include VAT • Free shipping over €100
Last Updated on 30 January 2026 by the5krunner
My favourite kit and nutrition
- Maurten — the race nutrition trusted by elite athletes. Gels and drink mix engineered to be easy on the stomach.
- Garmin 90-degree charging adapter — the small adapter that keeps your charging cable tidy at the stem. Essential for race day.
- Garmin charging puck — the fastest and most reliable way to top up your Garmin before a session.
- Ravemen FR300 — front light that mounts directly under your Garmin or Wahoo head unit. Keeps your bars clean and your beam pointed where it matters.
- Garmin Varia RTL515 — radar rear light that alerts you to vehicles approaching from behind. Pairs with your Edge or Garmin watch.
- Stryd — the footpod that brings running power to your Garmin. The single most useful running upgrade I have made.
- Favero Assioma Pro RS2 — the power meter pedals most serious cyclists end up choosing. Accurate, easy to move between bikes.
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. ID