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FLOWBIO Accessories FLOWBIO XMiles

FLOWBIO

Visit the FLOWBIO store

The FLOWBIO Sensor is a revolutionary wearable designed to take the guesswork out of hydration. As the most accurate sweat sensor on the market, it delivers real-time insights into your fluid and sodium loss as you train.

Designed by athletes for athletes to prevent dehydration hangovers, cramping, disrupted post-race sleep, empty legs and poor recovery.

Hydration has been a neglected pillar of performance - until now.

  • Real-time sweat rate and sodium loss tracking
  • Tailored hydration insights via the FLOWBIO App
  • Integrates with Garmin, Wahoo, Zwift & COROS
  • Works with your preferred electrolyte brand
  • No subscription fees – one-time purchase
  • 100-hour battery life with USB-C charging

FLOWBIO

Visit the FLOWBIO store

£379.00
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Standard delivery is delivered via Royal Mail within 3–5 working days. Alternatively, select 24/7 InPost Lockers for a flexible pick-up option.

How to use?

Secure the sensor to your arm or chest strap, start your workout, and sync data with the FLOWBIO App.

When to use?

Ideal for cycling, running, or walking workouts where hydration management is key.

Why do I need this?

To stop guessing and start fuelling your body with exactly what it needs to perform and recover properly.

Who uses this?

Endurance athletes, triathletes, cyclists, and runners who take their performance seriously.

Description

Whether you're clocking up miles on the bike or pushing the pace on a run, FLOWBIO provides personalised, science-backed hydration data that helps you perform better and recover faster.

This powerful device measures your sweat rate (L/HR), sodium concentration (MG/L), and skin temperature while you train.

The data is synced to the FLOWBIO App, which uses advanced algorithms to deliver tailored hydration recommendations based on your physiology and environment.

It's more than just a sweat tracker, it’s a smart hydration coach. You’ll get preparation tips before sessions and recovery advice after, all aimed at optimising your performance from the inside out.

The FLOWBIO Sensor fits seamlessly into your existing setup. It can be worn on your upper arm using the included FLOWBIO strap or integrated with your current HR chest strap.

With a 100-hour battery life, USB-C charging, and upcoming compatibility with iOS and Android (Summer 2025), it's built for endurance.

The app also integrates with Garmin, Zwift, Wahoo, and Coros, and even supports your preferred electrolyte brand, making it the ultimate tool for athletes who demand data-driven decisions.

What truly sets FLOWBIO apart is its accuracy and accessibility. With lab-verified precision of up to 90% and practical in-field accuracy as high as 83% for sodium loss, it's a game-changer for serious endurance athletes.

And unlike other systems, there are no ongoing subscription fees—just a one-time investment in smarter training.

How does it work

The FLOWBIO Sensor uses advanced biosensing technology to collect and analyse your sweat in real time; nothing invasive.

The device detects both fluid and sodium loss through microfluidic channels and biochemical sensors, which sits comfortably on your skin during activity. Proprietary algorithms process this data, offering an accurate estimate of your hydration losses.

Once synced to the FLOWBIO App, you receive clear, actionable insights on how to hydrate before, during, and after sessions. Whether you’re preparing for a race or adjusting your intake post-workout, the app helps you fine-tune your hydration strategy. As a result, you reduce fatigue, prevent cramps, and recover more efficiently, without the need for guesswork or lab testing.

About FLOWBIO

FLOWBIO was founded by athletes and engineers who've struggled with hydration issues throughout their amateur and competitive athletic careers. Their mission has always been rooted in giving athletes the critical data they need to help maximise their performance and recovery, with science and physiology at the heart of everything they build. Based out of London, the team at FLOWBIO spans across hardware, software, physiology, biotechnology and product. The FLOWBIO Sensor is the product of five years of research and development. At XMiles, we are so excited to be working with them to get this device into every athletes’ hands.