Matt Damon Used A Body Double Instead Of Going Christian Bale For The Martian
It's not uncommon for an actor to change their body for a role. If they're portraying a professional athlete for instance, they may want to get into peak physical condition in order to better embody the character. The opposite may be true if they are playing a normal person in their next movie; they may shed all their newly sculpted muscles because a suburban dad in a family comedy doesn't need to be ripped to the gills.
Few actors take this idea more seriously than Christian Bale. Bale has been known to undergo radical body transformations for roles, and this doesn't just mean getting into shape. He gained around 40 pounds to play Dick Cheney in "Vice," and lost 60 pounds for "The Machinist" — and that was only due to a typo in the script!
Obviously, such rapid gaining and losing of weight is extremely unhealthy, and at this point even Bale himself has said he's done making such preposterous health choices just for the sake of acting. But even so, Bale's willingness to put his body through hell for roles has changed the expectations surrounding other Hollywood stars.
When Matt Damon starred in "The Martian," there was a portion of the script during which Damon's character, Mark Watney, becomes pretty emaciated while struggling to survive alone on Mars. While some Bale-style weight loss was initially planned, according to a Maclean's interview, scheduling factors led to Damon ultimately not going through with it.
Going full Bale
Damon told Maclean's that he originally planned to go full Bale mode before the film's scheduling got in the way, giving a nod to "Cast Away," another movie that begins with the protagonist at a healthy size and has a time jump during which they lose a lot of weight. However, that required the production taking a break for a full year so that Tom Hanks could lose 50lbs, and "The Martian" ultimately didn't have the same luxury:
"Well, we were going to shoot it like that, like the way they shot 'Cast Away.' I was going to lose a bunch of weight in the third act of the movie, then put the weight back on. But with the way the schedule worked out, we went to Budapest, and then we went to Jordan to shoot exteriors. And we had to shoot exteriors for the beginning, middle and end of the movie. So we used a body double. It was, like, two shots."
It's quite interesting that Damon, who didn't think it necessary to learn any science in preparation for his role in "The Martian," saw undergoing such rapid weight fluctuation as a reasonable course of action. It seems pretty clear which of those two things was a more drastic measure. Of course, Damon had done one of these rapid weight drops before, for "Courage Under Fire," though he acknowledges that his unhealthy approach losing weight messed up his metabolism ("I didn't do it in a smart way").
For Matt Damon's sake, I'm glad he didn't go through with the weight loss and subsequent gain. I like authentic acting as much as the next guy, but I'd really rather not have actors destroy their bodies and metabolisms for a few scenes in a movie that can easily be achieved with body doubles.