CORE 2

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CORE 2 Thermal Sensor represents the next generation of non-invasive core temperature monitoring, built for athletes who demand accuracy, comfort, and performance insights.

48% smaller and 30% lighter than the original CORE 1
Delivers real-time core temperature data with high precision.
Easy to wear on straps, bras, or directly on the skin.
Helps improve VO2 max, hemoglobin mass, and lactate threshold.
Used by Olympic champions, ultrarunners, and elite coaches

CORE 2

Visit the CORE store

3 948 kr

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member exclusive price

BBE

80 in stock, ready to be dispatched

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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?

Clip it to a heart rate strap, sports bra, or stick it directly to your skin — it's that simple.

When to use?

During training sessions, indoor workouts, or races in hot conditions.

Why do I need this?

It helps you understand your body’s heat response so you can adapt, pace better, and perform stronger.

Who uses this?

Olympic triathletes, endurance runners, cyclists, and any athlete looking to improve performance through heat training.

Description

Developed using GreenTEG’s advanced thermal sensing technology, CORE 2 helps athletes measure and manage thermal load in real time. It is trusted by elite performers and coaches worldwide, offering medically accurate data to support heat training, pacing, and acclimatization strategies.

Compared to its predecessor, CORE 2 is 48% smaller and 30% lighter, delivering improved wearability without sacrificing performance. Its compact form factor and modular clip design allow for flexible placement — whether worn with a chest strap, clipped to a sports bra, or directly on the skin. The LED indicator keeps users informed on battery life, device status, and charging progress, while its discreet build makes it easy to forget it's even there.

When paired with the CORE Mobile App, users gain access to deep performance metrics and training guidance. The system offers real-time thermal data, historical trends, and heat adaptation support — essential for those preparing for warm-weather events or aiming to improve physiological markers like VO2 max and lactate threshold.

With backing from scientific research and usage by Olympic-level athletes such as Kristian Blummenfelt, CORE 2 has become the gold standard for performance-driven thermal monitoring.

Whether you're training indoors, competing in a hot climate, or building long-term endurance, CORE 2 gives you the ability to track, adapt, and train smarter.

Its cutting-edge tech helps you stay ahead of heat stress, prevent performance dips, and fine-tune your approach to heat acclimation and recovery

How does it work

CORE 2 uses GreenTEG’s proprietary thermal energy transfer technology to calculate core body temperature through heat flux and skin temperature measurements.

By applying advanced algorithms, it delivers medically accurate readings — no skin patches or ingestible pills needed.

It constantly monitors your temperature during activity, providing real-time data that helps you manage heat stress and adapt your effort.

When synced with the CORE Mobile App and a heart rate monitor, CORE 2 becomes a powerful training tool.

Athletes can track how their core temperature evolves throughout a session, identify heat-related fatigue early, and implement data-informed strategies like cooling breaks or pacing adjustments.

Over time, this builds stronger heat tolerance and enhances endurance performance — especially in tough environments.

About CORE

Train and perform at your absolute best with the most accurate non-invasive wearable device for continuous core body temperature monitoring.

The sensor allows you to easily see how much your core temperature rises with effort, so you can train your body to adapt to internal and external heat. You can also design personalized cooling protocols crucial to helping you sustain your power and pace on race day. With CORE, you’ll be ready to perform at your absolute best in any conditions.