Maximuscle, the muscle-building powders used by sports stars including Josh Lewsey, the England rugby wing, has been put up for sale by its private-equity owners.

Bidders including Barclays Private Equity and Phoenix Equity Partners are among those expected to submit first-round offers for the business by a deadline at the end of October.

The business, which is expected to fetch as much as £80 million, is owned by Piper, the management and private equity firm. It appointed Pricewater-houseCoopers to evaluate options and last month information was sent to several interested parties, including international corporate buyers as well as a string of mid-market private equity firms.

One bidder, who declined to be named, said: “This is expected to be a rapidly growing business as gym usage continues to rise.”

Maximuscle manufactures proteins, powders and vitamin supplements taken by bodybuilders and slimmers. They include Cyclone, Britain’s top-selling muscle formula, Promax, Progain and Viper. They are sold in chains such as Argos and JJB Sports, as well as gyms and specialist stores.

Among its customers is Lewsey, the England and Wasps rugby player, who scored the only try in England’s semi-final victory over France in this month’s Rugby World Cup. He states on the Maximuscle website that the firm’s products have “significantly helped me in reaching my fitness goals”.

Trade buyers who might consider bidding for the business include Premier Foods, Nestlé and Kerry.

Maximuscle was founded by Zef Eisenberg, who sold a majority stake to Piper, the buyout group, for £10 million in 2004. Management, led by Paul Hick, also took part in the buyout.

The deal comes as private equity firms struggle to raise enough debt to get deals done. However, given the size of the Maximuscle deal, which is under the £100 million mark, it is unlikely that suitors will find it hard to finance the transaction because it will involve only one or two banks.

One bidding source said that, as a result of the credit crisis, it was becoming common for private equity firms at the lower end of the market to offer to provide all the financing upfront thermselves in cash, as an incentive to get the deal done quickly.

That reduces the risk for the seller and means that the private equity buyer has to take on the risk of getting in the lending banks after the deal is completed, not before, as was the case in the past during the M&A boom.

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