Since launching his career with his unforgettable turn as a troubled teen in 2001’s Donnie Darko, Gyllenhaal has demonstrated a knack for astonishing physical transformations.
To play a ghoulish freelance news cameraman in the 2014 thriller Nightcrawler, he lived on kale salad and chewing gum and ran 25km a day to set, dropping 13kg.
“The running thing, you’re pretty hungry because you’re not eating a lot of food,” he told Entertainment Weekly at the time, adding that the regime took a toll on his social life.
“You’re lonely because you’re not meeting your friends for dinner. People go, ‘Hey you want to meet for dinner after work?’ I go, ‘Well, I’m shooting all night.’ ‘Alright, you want to meet for lunch?’ I’m like, ‘I can’t!’ So, I’m gonna go run.”
He then trained for six months and packed muscle back on to play a boxer in 2015’s Southpaw, however, the actor told BBC DJ Chris Evans that his motivation for training is never aesthetic.
“There’s a misunderstanding about the reasons why I particularly do what I do,” said Gyllenhaal, who was eating six or seven meals a day to keep up his strength.
“I didn’t know how to box before I started this movie and the way we were going to shoot it was as real as possible. And I just tried to spend almost five hours a day learning how to box. Over time, you get into shape.”
Away from work, the actor, who in the past has been coupled up with famous faces including Kirsten Dunst, Taylor Swift and Reese Witherspoon, has fought hard to keep his five-year romance with French model Jeanne Cadieu away from the spotlight.
“It’s no secret that I’m in a relationship and it’s a wonderful relationship,” he told People in September. “We are private, but guess we are who we are.”
Where to watch Road House in Australia
Road House streams on Prime Video from March 21. Stream it on Prime Video from $9.99/mth, with a 30-day free trial.