The campaign, which was created in-house, appeared on the sides of vans. It featured a picture of a woman wearing a pair of shorts and a sports top, bending over.
The ad, whose caption said: "Inviting? Perhaps, but at Virgin Active we bend over backwards", received complaints that it was offensive and demeaning to women.
The campaign went on to say that the gym was "no bum deal, with its two huge pools, huge gym... outstanding customer service and a peachy price -- it's right up your alley".
The ASA is concerned that Virgin Active failed to follow the advice of the Committee for Advertising Practice, and has asked Virgin Active to change its advertising strategy.
The campaign was part of a 拢1.5m multimedia campaign planned and bought by Upward Brown Media to back the launch of the brand.
Virgin Active is opening 11 health and fitness centres across the country, some of which will have a membership capacity of 8,000.
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