Our guest expert for this episode is Sarah Williams: the host of the ‘Tough Girl’ podcast. Sarah interviews women demonstrating extreme levels of mental toughness and is sharing with Rundamentalists readers the key attributes needed to tackle life’s biggest challenges.

Sarah isn’t just about tough ‘talk’, she also puts her words into action and is currently training for the grueling Marathon des Sables (6 marathons in 6 days across the Sahara desert).

Highlighting the stories of three amazing women, Sarah will inspire you to harness your mental strength to become literally: unstoppable.