And as these astonishing pictures show â€“ heâ€™s kept his moving promise.
Mr Matthews, 25, was declared clinically dead after his heart stopped for five minutes on the operating table.
He pulled through to be given the life saving transplant and was warned by medics that heâ€™d have to â€˜take it easy,â€™ for the rest of his life.
But the adrenalin junkie vowed there was only one way to make the most of his second chance at life and that was to live it to the full.
Just one year after the operation he completed his first marathon.
And now, four years later, heâ€™s thought to be the current fastest man in Britain on his second heart after completing the 100metres in an astonishing 11.06 seconds.
He has also joined a rugby team, despite being warned he would never play again, and completed a parachute jump from 18,000-feet.
His other hobbies include surfing, snowboarding and mountain biking.
â€˜To take it easy just wouldnâ€™t be living for me,’ he said. ‘Whatâ€™s the point of being given a second chance if you donâ€™t make the most if it?
â€˜Iâ€™m an example of how good life can be after receiving the most amazing gift. If it wasnâ€™t for the hero who donated his organ none of this would be possible and I thank him for that every day.â€™
Now Mr Matthews hopes these images from his personal photo album will help inspire other transplant patients and encourage more people to register as a donor.
The fitness fanatic was studying in California when he complained of breathlessness and his doctor referred him for tests.
An X ray revealed he had a grossly enlarged heart â€“ know as dilated cardiomyopathy â€“ and fluid on his lungs.
He was admitted to hospital, but was failing to respond to treatment when doctors also spotted an arrhythmia, or irregular heartbeat.
His heart was slowing to nothing and starting again and doctors feared he was at an immediate risk of a fatal heart attack.
His family were contacted and told to get to his bedside as soon as possible.
Parents Tony Matthews, 50 and Alison, 47, raced from their homes in Lowestoft and arrived in time for surgery to fit a defibrillator to shock his heart back into action should it stop.
But after the operation in March, 2006, and with the device in place, his heart was slowed to test it but stopped all together.
Doctors battled for five minutes to re-start it and at one point he was declared clinically dead.
A consultant at Stamford Hospital warned that the then 18-year-old had suffered complete heart failure and they were doing all they could to keep him alive.
He eventually came round to be told he would die without a heart transplant.
Mr Matthews remained hooked up to machinery to keep him alive while the hunt for a donor heart began.
It was only when doctors told him he would never play rugby again that he broke down.
â€˜I admit I cried because I loved rugby. I lived for playing and couldnâ€™t imagine life without it. But at the same time I was too young to die.â€™
He celebrated his 19th birthday in hospital. Finally a month later a donor was found.
He said: â€˜My mum burst into tears but I was on such a high. It was the best feeling ever and I couldnâ€™t wait to get into theatre.â€™
The six-hour operation began at 11pm that night.
Mr Matthews and his family were warned the next few days were critical as his body might reject the heart.
But within days he was up and about and left hospital just two weeks later.
Every day he returned for tests and even got to hold his old heart.
He said: â€˜It was funny to say goodbye to it, very surreal. Not many people get the chance to hold their hearts.â€™
While recovering he wrote a letter to the donorâ€™s family.
â€˜I didnâ€™t know anything about the donor but I wanted to let the family know that their loved one would get a good life out of me. I owed it to both of us to make the most of the amazing second chance the donor had given me.â€™
When friends ran a half marathon to help raise funds to pay for his treatment, he joked about completing the race himself the following year.
â€˜Everyone laughed, but it got me thinking and a month after the operation I started jogging.
â€˜Of course my mum was really worried so I jumped up and down to show her the heart wasnâ€™t t going to fall out.â€™
Just 12 weeks later he completed a six-mile run.
â€˜I walked half of it but it just felt amazing to be living again after being so close to death. To me sitting on the sofa watching TV and taking it easy just wouldnâ€™t be living.â€™
A few months later in November 2006, he moved back home to the UK and applied for the London Marathon 2007.
Heâ€™s since gone on to run it again, as well as representing Britain on the track in the World Transplant Games.
Last year he was one of only two international competitors sprinting 100 metres and his time of 11.06 was the fastest recorded.
â€˜It meant I was the fastest heart recipient in Britain and quite possibly the world,â€™ he says.
But his proudest moment was playing his first game for Doncaster Phoenix RFU in 2010.
â€˜Rugby is what the doctors had been most concerned about because itâ€™s a contact sport but I wouldnâ€™t have played if I didnâ€™t feel ready.
â€˜I didnâ€™t tell any of the other guys Iâ€™d had a transplant because I didnâ€™t want special treatment. Of course there was a risk I could get hurt, but I knew that would only happen if I didnâ€™t give it 110 per cent.
â€˜I loved being back on the field. Iâ€™m only young and I have to do the things I love or Iâ€™d be wasting this opportunity.â€™
He recently headed to Switzerland as part of the British snowboarding team competing in the World Winter Transplant Games.
His transplant has even lead him to love and he now lives in Retford, Nottinghamshire with teacher girlfriend Hannah Lilley whoâ€™s dad David Lilley underwent a kidney transplant.
â€˜Now I finally feel the heart belongs to me because I have made it my own, but I believe living life to the max is the only fitting tribute I can pay my donor for making it possible.
‘Iâ€™m very competitive and took the transplant as a challenge. I wanted to recover quicker and better than anyone who has had a heart transplant before.‘