Jake Gyllenhaal always watches his movies twice.

The 'Southpaw' actor thinks he gets a better ''perspective'' and can take things in properly if he doesn't just watch his performances once.

He said: ''I think the first time you watch anything, you're like, 'Woah', and then you watch it again and it's better.

''My rule is always to watch it twice to really get perspective.''

Though the 34-year-old actor had to bulk up to play a heavyweight boxer in 'Southpaw', exercising for five hours a day for five months, he found it more difficult shedding the pounds for his role in 'Nightcrawler'.

He told heat magazine: ''I'd say that depriving myself, both psychologically and with food, like I did in 'Nightcrawler' was particularly hard.

''And it was a totally different character - the character in 'Southpaw' is surrounded by a great family and is a really loving guy, deep down.

''But I don't think the same about Lou Bloom in 'Nightcrawler'.''