Sandra Bullock was like a ''six year old'' making 'Gravity'.
The 49-year-old actress plays medical engineer Ryan Stone in the space drama and found long days shooting specially-choreographed sequences in a special rig took their toll on her body and she got increasingly moody, though she had faith in director Alfonso Cuaron's vision for the film.
She said: ''I was frustrated. I would constantly get mad at Alfonso. I would complain because my back hurt... I was like a six year old. But it was all worth it. Never once did I think he couldn't pull it off.''
However, Sandra admits she worked hard to get in shape before filming commenced so she would be able to cope better with the tricky space sequences.
She said: ''I did know I was going to have to be terribly agile to do all the things I needed while pretending to be in zero gravity, so I got as fit as possible. I did a lot of exercise - I don't do crazy diets.''
And though she enjoyed working on the film, the brunette beauty has no desire to go into space in real life.
She told Britain's Hello! magazine: ''It was fun to make 'Gravity' but I have no desire to go into space - I like it too much here on earth.''