Shahid and Vishal shared notes on his look and character in the film, "The challenge was to be able to go from one role to another seamlessly without any time wastage, as we did not have the luxury of shooting each character separately. There were times when I had to shoot for both the characters on the same day. I was so into it that at times, after wraps, I actually felt like I were two different people."
It took Shahid nearly eight months to get a whipcord body for the film. He trained five days a week and two hours a day. He recalls, "Charlie was not about to have a chiselled, picture perfect body. Vishal's visualised a distinct look for the character but left it to me to decide what his exact physique. I envisioned Charlie as a tough street fighter. He needed to look tough and strong rather than sport a gym toned look. It's a lean and mean but not clean look, the grunge adds to the dark portrayal of the character."
Trainer Abbas Ali, says, "It took us eight months of advanced training to get this look. Our focus was on form, speed and power. For a running shot in Kaminey where Shahid had to run topless, my aim was to make him look like a sprinter, not an actor." Abbas says, "Being a vegetarian posed a challenge in the way of building the physique that Shahid wanted. We followed a diet of high carbs, moderate proteins and moderate good fats We removed maida from his diet and gave him muesli, oats, and protein shakes. He was not allowed any sugar and oil. He had to eat at the right time and in right combinations."