London fitness trainer Joe Wicks has raced to the top of the book charts, with his debut book Lean In 15.
His nutrition and exercise advice have gathered his a millions of fans and leagues of celebrity endorsements over the past year.
His debut book was released on December 28th and has since become the fastest selling book ever released by a chef.
The book contains more than 100 recipes that can be prepared in 15 minutes or less, he claims.
Accompanying the book is a number of demonstrative videos, where he shows people how to "eat more and exercise more".
His fitness videos have become an online sensation, where he breaks down challenging, high intensity work-outs and shows how they can be performed without expensive gym equipment or supervision.