Jack Black – Undisclosed
Jack Black’s character and physique can both be described as robust, and the actor never paid any attention to his body. However, when Kyle Glass, his Tenacious B bandmate, went through a dramatic weight loss transformation, it inspired Black to do the same.
He began by adopting a low-carb diet and then went on to do some rigorous fitness training that included various high-intensity exercises. As a result, the 49-year old actor himself had a dramatic transformation. Rumors started swirling that he’d used drugs to help lose weight, but there has been no such proof. We think the credit should be given to Jack Black’s determination and effort.