Demi Lovato has let fans know how she likes to relax when she's not working.

The Heart Attack singer, 20 - who's also a judge on Simon Cowell's show US X Factor - last night revealed she enjoys clambering up walls.

'I love rock climbing,' she Tweeted alongside a snap of herself scaling a sheer face at an indoor activity centre. 

But 21-year-old Selena Gomez's BFF warned followers that her hobby can have painful consequences if necessary safety procedures are ignored.   

'That one time I sprained my foot because I was the idiot that rock-climbed without strapping into a harness first. Not my brightest moment,' said Demi.

'Worst part is - I wasn't trying to be ballsy. I just forgot... WHO DOES THAT?!!!!??!!!'

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Beth Shearing