The Consumer Council is advising members of the shuttered Physical Fitness chain not to rush into signing up with a new operator that took over one of its sites.

As of 9am on Monday, the watchdog had received more than 4,000 complaints about the chain's closure, involving customer losses totalling HK$135 million.

The Wan Chai branch reopened under the name "Healthy" last week, with Physical members invited to use it as long as they sign a consent form.

But Gilly Wong, the council’s chief executive, said the form is “confusing and unclear”.

“It looks like an application form to a new membership, but on the other hand, the new merchant said it is not liable to the service of the existing merchant. And also it can reject the application… It is a little bit contradictory and also quite confusing,” she said.

“Since there’s no time limit for the members to sign this application form, we believe it’s much more prudent to wait and see how the situation goes.”

With the government seeking to review prepaid services in the fitness sector, Wong said the trade could play its part by introducing a “cooling-off period” for new contracts to be cancelled if the customer wishes.

“Without any hesitation and any delay, the industry actually can review their conduct and be disciplined about how to serve the consumers and implement their own voluntary cooling-off period, in order to increase the confidence of their customers,” she said.

“It is a meaningful one, not just a cosmetic one. Because in the past, in the fitness industry, we observe that even the customer was entitled to the cooling-off period, but simply by a touch of a button of the [gym] machine that would waive the cooling-off period.”