In The Program, Ben Foster plays renowned champion cyclist Lance Armstrong, who gave up his prestigious titles when it was revealed that he had been using performance-enhancing drugs in order to obtain them. A new trailer shows off Foster’s intensity in the role, which the actor says he achieved with the help of a little performance-enhancement of his own.

In an interview with The Guardian, Foster says that he doped himself up in order to fully understand Armstrong’s experience, though he’s hardly glorifying the idea:

I don’t want to talk about the names of the drugs I took… Even discussing it feels tricky because it isn’t something I’d recommend to fellow actors. These are very serious chemicals and they affect your body in real ways. For my own investigation it was important for me privately to understand it. And they work.

As you might expect, those drugs had a serious effect on Foster, who says he’s just now getting back to normal:

There’s a fallout. Doping affects your mind. It doesn’t make you feel high. There are behaviours when you’ve got those chemicals running through your body that serve you on the bike but which, when you’re not … I’ve only just recovered physically. I’m only now getting my levels back.

Foster’s commitment to The Program both in front of and behind the camera is impressive, and you can hardly blame him for his curiosity. So often we see actors playing parts that require them to act high on certain drugs, and it’s pretty easy to tell when that particular actor has never been under the influence of that particular drug. Even though the majority of us who sit through The Program will have no idea what it’s actually like to use performance-enhancing drugs, Foster’s risk may very well pay off and lend the part more realism.

The Program is directed by Stephen Frears and also stars Chris O’Dowd, Jesse Plemons and Guillaume Canet, and hits theaters in the UK on October 16. There is no official US release date yet.