Mischa Barton hit the gym yesterday, in an encouraging sign that her recent hospital stay may have finally persuaded her to adopt a healthier lifestyle.

The actress – who has sparked concern over her yo-yoing weight  – was snapped emerging from Equinox gym in New York with a girlfriend.

And, judging by Mischa's pained expression (below), it was her first workout in a while.

Mischa rewarded herself for her exertions with a spot of shopping at Sephora, before hailing a taxi.

The former OC star spent several weeks in hospital, reportedly under an unvoluntary psychiatric hold, for an undisclosed illness last month.

Mischa is in New York to start work on new TV series The Beautiful Life.

Mischa at Paris Fashion Week earlier this year