The Planet Fitness gym appears to be sending out conflicting messages to its members to meet its policy that bans gym-timidation.

On Monday, it asked Tiffany Austin from Richmond, California, who just signed up that day, to cover up by putting on a shirt or blouse over her halter top because members were intimidated by her toned body.

Ms Austin was just on the treadmill for 15 minutes when the staff noticed her visibly trim midriff. Angered by what happened, she quit her membership, saying, "I felt intimidated and harassed by the place that says no intimidation."

Similar complaints have been made by other members with great physiques because of the gym's dress code which is decided upon the discretion of Planet Fitness managers.

Planet Fitness - which aims for a hassle-free environment and uses as a trademark Judgement Free Zone - counts 5 million members.

However, at the gym's Albuquerque facility, a female Muslim convert, Tarainia McDaniel, 37, disallowed her from using an informal head scar while working out, explaining that the headscarf breached Planet Fitness' dress code policy.

She defended her use of the scarf as part of her Islam religion, but was told to use instead a baseball cap. Ms McDaniel was born to Roman Catholic and Jehovah's Witness parents but converted to Islam when she was 16.

She also said that she had used a colourful head scarf in other Planet Fitness branches and never had a problem, until the staff at the Irving Boulevard branch disapproved of her use of the scarf.

As a result, Ms McDaniel filed a lawsuit against the gym under the New Mexico Human Rights Act and Unfair Practices Act.

Among the clothing items banned in Planet Fitness are jeans, work boots, bandanas, skull caps or revealing clothes when working out.