Preparing for a six-minute boxing match saw 36-year-old David Lindsay push his body to the limit. He lost 3st in three months.
But it was nothing compared to the struggles of Charlie Cronin, the 15-year-old girl he has raised over £3,000 for.
On Thursday, analytics officer David, of St John Street in Finsbury, fought in a white collar boxing match at the 02 Arena’s Indigo venue.
White collar boxing, an unofficial subdivision of the sport, is often associated with 1999 film Fight Club: disgruntled city professionals looking for a kick in life.
But in Charlie, the daughter of Andy Cronin, David’s school friend from Berkshire, he had a much more pressing reason to don the gloves.
Aged one, Charlie was diagnosed with Congenital Lymphangiectasia, a rare condition where the lining of the small bowel becomes enlarged and blocked.
By the age of seven, the bowel had rotted away.
In the intervening years, she has had two bowel transplants and fought lymphoma cancer.
At the start of this year, Charlie was also diagnosed with pneumonia and sepsis.
Even then, her condition somehow got worse.
Hours after the diagnosis, she went into cardiac arrest and was put on a life support machine.
And although she survived, the soft tissue in her legs died - and both of her legs had to be amputated below the knee.
David, who trained for the fight at Times Amateur Club in Barnsbury, pledged to raise money for prosphetic legs and a family holiday.
At Thursday’s bout, David admitted he was disappointed with his performance after only managing a draw in front of Charlie and her family.
But he added: “It’s just great to raise their profile.
“It’s been a nightmare for them. They really are an amazing family. Ever since Charlie was little, she’s suffered one thing after the other. It’s been a horrible slog.
“But the thing I’m amazed about is her resilience. I chat to her and she’s always chirpy. She’s always so upbeat, even having lost her legs. She is still determined to swim, and drive.”
Of Thursday’s match, against an oil trader from BP, David said: “As soon as I got to the 02, I felt really, really nervous. It dawned on me as soon as I saw all the seats, and realised there would be 600 pairs of eyes on me.
“I just remember stepping in the ring and the lights being so bright. Everything I had practised in my head went out of the window!
“It was a hard fight, and I’ll admit the adrenaline and nerves got to me. I could have done better - but it was an amazing night.”
David, who pledged to continue boxing, added: “It’s had a huge impact on my lifestyle. My job has always been sat at a computer.
“Over the years, I’ve not been particularly active and put weight on. I was 19st 7lbs and now I’m 16st 7lbs.
“That’s from three months of training and I’ve not been this light since I started working full-time. It’s turned my life around.
“I always enjoyed kickboxing but full contact boxing is a completely different game. The aggression aspect comes natural to me, as working on a trading desk is a very aggressive environment!
“I wasn’t sure how it was going to go when I started: how I would take a punch, for example. But that’s actually the part I don’t mind at all.”
To donate to David’s campaign, visit crowdfunding.justgiving.com/friends-of-charlie-cronin
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