The 6-foot-tall Jake, who’s normally about 180 pounds, starved himself down to 150 pounds to play a struggling crime reporter in “Nightcrawler,” Examiner reported.
“My mother was worried,” said Gyllenhaal. “She just wanted me to be careful, but she also knows how seriously I take what I do and she respects that.”
Jake subsisted on small pieces of meat, crackers or kale salad during the day and often didn’t eat anything at all at night. For exercise, Jake often ran 15 miles from his house to the set. “I would try to eat as few calories as possible,” said Gyllenhaal.
While the physical transformation is what most people notice, he said embodying a character is largely a mental process — a sentiment echoed by his former Prisoners co-star Hugh Jackman, who has followed extreme diets and workouts to achieve his rippling Wolverine body.
Jake is now healthier and buffer, having gained 15 pounds of solid muscle preparing for the boxing drama “Southpaw.” For “Southpaw,” Gyllenhaal spent six months working out six hours a day to play a professional boxer.
His workout routine included eight-mile runs and boxing workouts with real boxers, as well as strength-training moves such as pull-ups and tire flips.
Gyllenhaal previously packed on muscle for “Jarhead” (2005) and “Prince of Persia” (2010), so work-related weight loss and weight gain is nothing new for the dedicated actor. Fortunately, Jake doesn’t mind intense exercise.
While most people resolve to work out more, Jake is a self-professed workout addict who has to make an effort to exercise less. “I’ve had to teach myself to slow down a bit,” he said. “Because I get so into [working out], it becomes a real addiction.”