Chamonix , France



Sport Types
  • Running
  • Adventure Racing
  • 1-on-1 Coaching
  • Consultations
  • Group Coaching
  • Local Coaching
  • Remote Coaching
  • Mental Skills
Athlete Requirements
Curiosity and passion.
Meet Your Coach
Kaz Williams
Kaz Williams Mettle
Chamonix France
Coach Bio

Hi, I’m Kaz. I founded Mettle to help you take on trail and ultra running challenges that you are curious about, whether that's chasing a PB or your first ultra. If you are genuine about digging deep and building your physical and mental endurance, we provide: support and structure to achieve your goals; scientific training plans adapted to your life; and mental toughness strategies.

Because we believe:
You have the capability to improve.
You can raise your mental game.
You are unlimited.

Read More

Train with purpose. Race with confidence.

The story starts in the Chamonix mountains with one mission: to help runners like you break through your limitations and reach your greatest potential.

Mettle represents a dedication to continuous improvement by showing up, putting in the work, being healthy and having fun. Progress, not perfection. But make no mistake: this won’t always be easy. We will challenge you, every bit as deeply as we challenge ourselves, to do better than yesterday.

My trail running journey started in Chamonix, France with the Mont Blanc Marathon in 2010. I am crazy about running far on dirt, through forests, up mountains and by lakes. Favorite races include Tahoe 200, Moab 240, 1 loop at Barkley Marathons, Ouray 100, Across the Years (10 days), TDS (UTMB series) and Tot Dret, Italy.

Ready to take your fitness, your training or your mental game to a whole new level of running and success? Great! Let's talk.

We offer a free, no pressure, 20 minute call to talk about your running ambitions. Get in touch and book a coach call today. We’d love to hear from you and support you on your running journey.


Dr Kaz Williams
UESCA Running Coach and Performance Psychologist
Striving to help people find their mettle.

Preferred Athlete Levels
Beginner, Intermediate, Advanced
Have a question? Contact me.

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