Mountain GOAT Kilian Jornet swears by this muscle stimulation gadget, and its latest upgrade makes it easier to use anywhere

Few endurance athletes have pushed the limits of human performance quite like Kilian Jornet, whose extraordinary mountain-running exploits have made him a legend in the outdoor world.

While his training methods are undoubtedly more demanding than those of the average runner, one piece of recovery technology has apparently remained constant throughout much of his career.

That technology comes from Compex, which has announced its new Ultimate EMS range alongside a renewed partnership with Jornet, who has used the brand's electrical muscle stimulation devices since 2006.

The new generation introduces wireless stimulation pods, smartphone-based controls and upgraded muscle-scanning technology, all designed to make EMS easier to incorporate into training and recovery routines.

A smarter way to stimulate your muscles

Electrical muscle stimulation, or EMS, uses electrical impulses delivered through electrodes placed on the skin to trigger muscle contractions.

The technology is commonly associated with physiotherapy and rehabilitation, though athletes also use it for muscle activation, strength conditioning and recovery.

Compex has been developing EMS devices for decades, but the new Ultimate range marks a shift towards a more connected, portable experience.

The biggest change is the app-driven interface, which allows users to control their sessions from an iOS or Android smartphone.

The app offers structured training plans, as well as personalised goals and guidance on electrode placement.

Compex says its expandable catalogue of programmes covers everything from strength and endurance to massage and recovery.

The company has upgraded its Muscle Intelligence technology to MI 2.0, which the company claims delivers faster, more accurate muscle scanning and more responsive automatic intensity adjustments.

The wireless pods now use magnetic electrode connections for quicker setup, while a 15-minute charge provides enough power for a recovery session. Battery life is rated at up to five hours.

Good enough for one of the world's greatest endurance athletes?

Jornet's relationship with Compex stretches back almost two decades, having first used one of the company's devices following an injury in 2006.

Since then, he says EMS has become part of his wider approach to rehabilitation, strength training and recovery.

"The first time I used a Compex was after an injury in 2006, and since then it has been part of my routine in many different situations," Jornet explains.

"What I find particularly valuable is its ability to help activate muscles and support neuromuscular function without adding unnecessary mechanical load."

Of course, EMS isn't a shortcut to improved fitness, and the evidence supporting its various applications differs depending on the intended outcome.

It's best considered a supplementary tool rather than a replacement for conventional training and recovery practices.

Nevertheless, the new Ultimate range looks like a significant usability upgrade for athletes who already incorporate muscle stimulation into their routines.

The Compex Ultimate will cost £850 in the UK, with the official launch currently expected around mid-November 2026. The exact release date has yet to be confirmed.