Shooting a gravity-free make-out scene with Kirsten Dunst was a terrible way for Jim Sturgess to spend his birthday - because he had been out celebrating the night before.

The Brit romances the Spider-Man star in quirky new film Upside Down, in which their characters live in parallel worlds, and Sturgess admits he should have cut back on his drinking the night before one mind-bending romantic scene.

He tells Vh1 Big Morning Buzz Live, "It was actually the worst day of filming that we had; it was my birthday the day before so I had been out and had a few drinks. Not good when they're spinning you around on wires for, like, 15 hours at a time."

Sturgess admits it was a very uncomfortable film all round because he had to spend large parts of it hanging upside down.

He tells Wenn, "There's a few scenes where they really did strap me up to the ceiling and I had to act the entire scene with the blood pumping down into my eyeballs! I was nauseous but I actually learned to stand upside down (for) up to 20 minutes on my head, which I found out is really good for you.

"They gave me a pair of gravity boots and put them in my dressing room, so I can strap myself up into this thing and practise spending longer periods of time hanging upside down. I never felt so good actually. It's amazing how quickly you adapt to it because the first time I had to try it, it was like 30 seconds before I threw up in my mouth!"