Bradley Cooper recently gained a whopping 40 pounds of muscle for his newest movie, "American Sniper." According to Business Insider, the 40-year-old actor usually weighs in at around 185 pounds. However, in order to play the role of Navy SEAL Chris Kyle, Cooper had to bulk up to 225 pounds.

Just how did he do it? Well, Cooper has had a lot of experience. In an interview with Men's Health, he lauded diet and hard focus as the best ways to accelerate muscle growth.

In terms of diet, he cautions others not to cheat and fall back on unhealthy foods. He stated, "It's vital you allow your body to rid itself of toxins and keep your hormones at optimal levels. Sugar and processed food cause your body to respond in a way that prevents proper muscle growth."

As for hard focus? Well, he swears that "Staying focused on your goal helps you get through workouts and keeps you from cheating on your diet. Put a picture of what you want your body to look like in your kitchen. It's a constant reminder where you need it most."

However, becoming Chris Kyle was a different story. Cooper stated, "I had to get to the point where I believed I was him... At 185 pounds, it would've been a joke. His size was such a part of who he was. Chris wasn't ripped. He wasn't sinewy. He was just a bear."

Cooper had a total of 10 weeks in order to pull off his epic transformation. Men's Health reports that Cooper and trainer Jason Walsh trained twice a day. The first workout began at 5 a.m., and focused on structural exercises like deadlifts and squats to build a foundation solid enough to hold the extra mass.

The second workout took place later in the afternoon, and focused on traditional muscle-building exercises. Unilateral exercises like Bulgarian split squats and single-leg deadlifts were also implemented.

A heavier diet was also necessary. Cooper ate more than 5,000 calories every day, which he said came as a shock to his body. He joked, "If it's pizza and cake, that's one thing. Putting 6,000 calories a day in your body gets old quick."

What do you think of Cooper's intense workout routine? One thing's for sure - it paid off.