The There Will Be Blood star had to round out his "scrawny physique" to accurately portray Wilson as a young man in Love & Mercy, but he took the idea a little further than Pohlad had expected.

He tells U.S. talk show host Jimmy Kimmel, "I gained at first, like, 35 pounds and I showed up to my costume fitting and my director was like, 'Wow, you still have to look good!'"

Dano admits his larger figure made him feel "really sexy" at times, but that doesn't mean there weren't down sides to piling on all the extra weight.

He says, "I felt pretty bloated and sweaty most of the time. I had to eat like, 4,500 calories a day, I tried to do it as healthy as possible, but at the end of the night, if I hadn't hit the math, I would just get a pint of coconut ice cream and a bottle of red wine and just... go to town!"

Dano even blames his heavier frame for causing him to suffer an injury on the basketball court at the end of the shoot in 2013, leaving him in need of surgery. The operation forced him to delay plans to get back into shape and he confesses it was "great" to have his girlfriend wait on him hand and foot.

He explains, "I actually tore my ACL (anterior cruciate ligament) playing basketball, with the 30 extra pounds, because I don't think my scrawny physique was prepared for that extra weight, so right when I finished filming, I had knee surgery, and then I laid on the couch for a few weeks like, fat and on painkillers. And that was great. You just lay there and you just want somebody to feed you. It was kind of a great feeling."