(CNN)Lee Pearson has had 14 major operations, has a form of scar tissue in his limbs where muscle should exist, and lives with plastic splints encasing his legs from hip to heel.
Lee Pearson: Out of two closets, into Paralympic history
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No wonder he thinks his "greatest achievement is ever getting on a horse in the first place."
The 41-year-old, born with arthrogryposis multiplex congenita, is nevertheless one of the most successful -- and flamboyant -- athletes in British history.
That's despite starting life in a cupboard.
"I was put in a broom cupboard for three days. I presume they didn't think I would live," says Pearson of his birth.
"They had my mum sedated. On the third day, she came round and wanted to know if she had a baby that was alive or not.
"They pushed her in a wheelchair down to a broom cupboard with mattresses, and buckets, and mops -- and there was a cot at the back with a blanket over it. So mum took a deep breath, because she thought if she reacted badly, the professionals would take me away."
Lee's mother Lynda was a psychiatric nurse. His father, Dave, drove trucks.
"My husband turned up and I said: Where's my baby?" Lynda once recalled to the BBC.
"He said: 'He's downstairs, his legs are a bit blue.' That turned out to be the understatement of 1974.
"He didn't actually get onto his feet until he was six."
Pearson has since swapped the cupboard for a trophy cabinet boasting 10 Paralympic gold medals in dressage, alongside two dozen European and world titles.
He has also exited a second closet, coming out to his parents in his twenties and subsequently becoming one of the UK's highest-profile gay athletes.
In 2014, ahead of a planned trip to decry anti-gay propaganda at the Sochi Winter Olympics, Pearson almost dared Russian President Vladimir Putin to throw him in jail.
"Then the Prime Minister and my country would have to get involved and that would add to the embarrassment for Russia," he declared to reporters.
Tanni Grey-Thompson, a winner of 11 Paralympic gold medals in track and field, hailed Pearson as a Paralympian whose "personality blows everyone else out of the water" in the run-up to his home London Games.
Pearson has, only half-jokingly, described his athletic preparation as "curry, Malibu and Coke" and tells tales of escorts to parties from local police at the Beijing Paralympics.
Even as a child, Pearson made headlines. In 1980, while presenting the six-year-old with a Children of Courage award, Prime Minister Margaret Thatcher carried Pearson up the staircase at 10 Downing Street.
The same condition that left Pearson unable to climb the stairs made his talent for dressage riding all the harder to finesse.
"There are no muscles in my arms to actually bend my arms," Pearson, who is an ambassador for the Midlands Air Ambulance, explained to CNN. "I can pull with the shoulders and I got into riding because I couldn't pedal a bicycle."
The first animal he sat astride is a far cry from the high pedigree horses -- such as gelding Zion -- he has enjoyed so much success on.
"There was a donkey in the local farmer's field, so dad brought it home one day and plonked me on top," added Pearson.
Riding lessons followed, while his parents saved up for a pony that arrived two Christmases later.
"That Christmas was amazing," recalled Pearson. "From day one, though, the pony put his head down and went, 'You're not very balanced, you're not very strong. I'm just going to buck you off every day.'
"When people chat to me about my childhood and getting into horses, they're like, 'Was it like the birds sang and the sun came out? Was it an amazing experience?'
"I'm like, 'No, it was rubbish. I was frightened. I was pretty unbalanced and most ponies took advantage of me.'"
Pearson ended up with a desk job until he saw the 1996 Atlanta Paralympics on TV and decided to try riding as a sport, though being allergic to horses did not help -- he still takes antihistamines daily.
Nor, he admits, did he initially cope well with disability sport.
"I was actually quite phobic. I kind-of panicked if anybody in a wheelchair was rolling towards me," he said.
"I was like a straight man in a gay club. I was up against a wall thinking, 'Oh my god, these disabled people everywhere!'
"But the great thing is, if I'm discussing disability [now], I know what it's like to look at someone a bit different. I know about being ignorant about it, and I also know the next level of being frightened about disability.
"The Paralympic Games actually turned my whole mentality around about disability. When you're in the Paralympic athletes' village and there are 4,000 disabled people, you stop seeing disability. Totally."
Despite the allergies and his initial unease about disability sport, Pearson's rare talent helped ease the transition.
On his Paralympic debut, at the Sydney 2000 Games, he won all three gold medals available to him. He did the same in Athens four years later, having won able-bodied events in the interim, and won a treble again in Hong Kong -- site of the Beijing Games' equestrian events -- in 2008.
That gave him the chance of surpassing the likes of Grey-Thompson, Sarah Storey and David Roberts, each Britons with 11 Paralympic titles, at London 2012.
But, a year before the London Games, Pearson broke his back in a training accident.
"I was airlifted out of my dad's field -- to his excitement," said Pearson, who is also an ambassador for Caudwell Children. "He was there with a video camera because he couldn't believe he'd got a helicopter in the field.
"He wasn't worried about me whatsoever," Pearson jokingly added.
He recovered to compete at the Paralympics and won a team gold medal, but missed out on individual titles.
A year later, he was dropped from the British team for the European Championships. Pearson and the British team say that is testament to the exceptional strength of the sport in Britain, and the increasingly tough opposition on the international circuit.
But the unseating of Pearson from his dressage throne proved temporary. Last year, at the World Equestrian Games, he and his latest ride -- Zion -- once again won all three gold medals on offer.
Pearson now looks to next year's Rio Paralympics as a chance to "prove a point" and regain all three Paralympic titles, if he is selected.
Maybe then, a knighthood would come.
Pearson has been vocal in his criticism of the British honors system: though he has collected the MBE, OBE and CBE, he has more than once observed that 10 gold medals would guarantee a knighthood for any able-bodied Olympian.
However, he insists neither honorifics, nor medals, are his primary motivation for carrying on to a fifth Paralympics.
"My motivation is paying the mortgage," he deadpanned. "No joke. Honestly.
"I still suffer with nerves and think, 'Why am I putting myself through this torture?' It's not actually the love of winning -- it's that building of a partnership with a horse.
"Just riding horses every day keeps me going. And that threat of losing the mortgage."