The hardest-hitting hero in Hollywood is back for another round.

Behind the scenes at his cover shoot for the January/February 2017 issue of Men's Fitness, Vin Diesel—star of the upcoming xXx: Return of Xander Cage and The Fate of the Furious—explains his most fundamental rules for life, how he sculpts a different physique for different characters, and what first inspired him to start working out.

Pick up the new January/February 2017 issue of Men's Fitness starring Vin Diesel on newsstands Monday, January 2 and available for download here.