Jake Gyllenhaal has built a hero’s body to play the lead role in the new swords-and-sandals action movie Prince of Persia: Sands of Time. Based on the popular video game, which follows an adventurous prince who teams up with a rival princess to stop an angry ruler from unleashing a sandstorm that could destroy the world, Gyllenhaal embarked a training programme to add size and strength to his frame, all under the watchful eye of personal trainer Simon Waterson (simonwaterson.com).

Here’s the workout that sculpted Gyllenhaal’s rock-hard abs, and below is his daily nutrition plan that packed on muscle whilst keeping him lean.

Get warrior abs
‘We did a lot of core work to build the stability Jake needed to wield a sword,’ explains Waterson. ‘This involved a high number of reps to help build muscular strength and endurance.’ On the right you'll find a tweaked version of one of the workouts Gyllenhaal regularly did for Prince of Persia.

Eat like a Prince
‘Eating little and often is the key to building muscle and staying lean,’ says Waterson. ‘Jake ate very healthily and didn’t have the fast-food mentality. We gave him lots of salads, vegetables and lean meat to keep his blood sugar levels stable throughout the day. A good formula for building muscle is to eat around 2g of protein per kilogram of bodyweight, and drink lots of water throughout the day.’

4.45am Pre-workout snack:
Espresso and banana

7am Post-workout breakfast:
Egg white omelette on rye bread

9am Early morning snack:
Protein shake

11am Mid-morning snack:
Apple or banana and handful of almonds and raisins

1pm Lunch:
Two chicken breasts with a huge salad of avocado, broccoli and other dark green leaves and veg

3pm Mid-afternoon snack:
Protein shake

7pm Dinner:
Steak with steamed veg or grilled chicken with couscous

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