He has made a career out of playing a diamond-hard boxer, and Sylvester Stallone, at 60, is not about to let Rocky fade away gently.

For decades the Hollywood muscleman espoused the benefits of bodybuilding, punishing exercise and tight nutrition regimes as the path to the physique that became a Tinseltown institution.

Now, it seems, there may have been another ingredient: human growth hormone.

Stallone was charged yesterday with trying to bring 48 vials of the banned muscle-building hormone into Australia when he visited last month to promote his latest film, Rocky Balboa. He faces a A$22,000 (£8,900) fine if found guilty.

Stallone, whose latest film tells the story of an aged boxer struggling to stay in fighting shape, was detained initially at Sydney airport after X-rays of his luggage revealed the vials. He and his entourage, who arrived by private jet, were allowed to go to their hotel while the vials were removed for tests.

When they were found to contain Jintropin – a brand name for a drug whose active ingredient is a human growth hormone – authorities raided the star’s hotel room two days later. Members of his party were spotted throwing objects out of the windows.

Authorities served Stallone with a court-attendance notice for allegedly importing human growth hormones, which are banned in Australia. Court documents allege that the star circled the “no” box when asked on his incoming passenger card if he was bringing in restricted or prohibited goods.

A Sydney magistrate granted Stallone’s lawyer a six-week adjournment after being told that he needed more time to gather material for his defence. Stallone will be required to enter a plea on April 24.

Peter Larkin, a former head of Australia’s National Drugs in Sports Committee, said yesterday that one of the great advantages of drugs containing growth hormone was that they made users look very trim and youthful.

“As you get older, you don’t make growth hormone,” Dr Larkin said. “So if you’re an older person and wanting to keep your body in shape and wanting to keep muscle tone, and wanting to keep physique, then this is one of the true fountain of youth drugs.” Overuse could cause knuckles, jaws and feet to enlarge, he said.

Stallone has denied using drugs to build up his body.

“To beat this guy you need speed – you don’t have it. And you got arthritis in your neck, and you’ve got calcium deposits on most of your joints, so sparring is out. So what we’ll be calling on is good old-fashioned blunt force trauma”

— Tony ‘Duke’ Evers, Rocky’s trainer, in Rocky Balboa

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