Actress Elsa Pataky is sharing the secret to her incredible physique in a new book.

The actress and wife of "Thor" star Chris Hemsworth will unlock the key to her healthy lifestyle in the publication, titled "Strong", reports aceshowbiz.com.

Pataky took to Instagram on October 25 to share the news, adding that she has been working on the book for "over a year".

"I'm really excited to announce that I will be launching my first Australian book on November 26th! This is your guidebook on how to live to a balanced and healthy life. My approach is about building strength of body and mind," she wrote.

"I share my advice for overcoming mind-traps and other challenges, as well as my favourite high-intensity exercise circuits that can be done from home.

"You'll also find nutrition advice and delicious, healthy recipes," Pataky added.

The Spanish-born actress previously released fitness tome "Intensidad Max" in her native country in 2014.

She shares three children with her actor husband; India, seven, and identical twins Tristan and Sasha, five.

In January, the couple launched fitness app Centr, which offers users a personalised digital health and fitness programme, alongside a hand-picked team of internationally renowned fitness experts.