The Irish actor, who plays Christian Grey in Fifty Shades of Grey, is fortunate enough to be able to eat whatever he wants and not put on weight. Jamie Dornan is naturally gifted and has a blessed metabolism.

To fit into the in-shape character of Christian Grey, Dornan had just one month to bulk up. The expert trainers at Iron Fit implemented a workout that resembled CrossFit, which helped Dornan get into shape quickly.

Dornan’s personal trainer Ramona Braganza says that Dornan follows an 80:20 kind of routine; 80% of his time is spent on working out and dieting, while 20% of his days are cheat days.

Dornan was a skinny guy initially, and wanted to put on muscle. He relied on simple carbs, regular cokes, and even ate 10 packs of hula hoops snacks a day.

When that failed, he turned to his trainer to help him gain weight while staying healthy. Dornan was required to increase his calorie intake in order to put on weight; his trainer insisted on including more protein, while lowering the carbohydrate intake during the day.