Sir Richard Branson has stepped up his astronaut training in preparation for a space flight he believes is just months away.
His optimism looks set to intensify a three-way-race between rival billionaires to conquer the private space market.
He told the BBC: “I’m going for astronaut training, I’m going for fitness training, centrifuge and other training, so that my body will hopefully cope well when I go into space.
"Instead of doing one set of tennis every morning and every evening, I'm doing two sets.
"I'm going kiting and biking - doing whatever it takes to make me as fit as possible."
In centrifuge training, memorably depicted by Roger Moore in the James Bond film Moonraker, the subject is subjected to high G-forces to simulate and prepare for the physical stresses of take-off.
It comes four years after tragedy struck the Virgin space programme, when its SpaceShipOne passenger rocket ship exploded, killing one pilot and leaving the other seriously injured.
This year the ship’s successor, the Virgin Galactic SpaceShipTwo, completed its first supersonic test flight.
In an interview to be broadcast on Monday, the Virgin founder told the BBC’s You and Yours programme that commercial passenger space flights were tantalisingly close.
“We’re talking about months away, not years away. It’s so close. There are exciting times ahead,” he said.
Two more of the world’s richest men are also engaged in the new space race.
SpaceX, funded by Paypal founder and tech entrepreneur Elon Musk, is increasingly dominant in the cargo market.
Mr Musk has said he wants to die on Mars, "but not on impact”.
But the first passenger flight looks likely to happen courtesy of either Mr Branson or Amazon founder Jeff Bezos.
Mr Branson said of Bezos: “I think we’re both neck and neck as to who will put people into space first.
“Ultimately, we have to do it safely. It’s more a race with ourselves to make sure we have the craft that are safe to put people up there.”
Earlier this month the Amazon boss - whose $130 billion fortune dwarfs Mr Branson’s twenty times over - said he is liquidating more than a billion dollars a month to invest in his space company Blue Origin.
He told a finance magazine: “The only way that I can see to deploy this much financial resource is by converting my Amazon winnings into space travel.
He said his own timetable was to put humans in space “at the end of this year or at the beginning of next.”
Mr Branson’s ambitions to exit the world’s atmosphere follow decades of effort to enter the world record books.
In 1985 an attempt on the Atlantic Ocean crossing record saw his boat capsize, leaving him in need of rescue just of the Cornish coast.
A second attempt a year later in the powerboat Atlantic Virgin Challenger II made history by making the trip in three days, eight hours and 31 minutes.
In the 1990s he set speed records in hot air balloons, but the goal of becoming the first man to circumnavigate the world by balloon continued to elude him.
The Swiss-British team of balloonists Bertrand Piccard and Brian Jones achieved the first round-the-world trip in March of 1999.