Super-fit pensioner Arthur Gilbert, 90, has taken part in 40 triathlons, which are made up of a 500 metre swim, a 12-mile bike ride and a three-mile run; he is now in training for his 41st - setting the world record for the Oldest triathlete.
The Guinness world record for the Oldest volunteer was set by Violet Robbins, who is a volunteer at the Prince of Wales Hospital, in Randwick, Sydney Australia, aged 107 years 11 months 25 days, as of 22 February 2010.
Guinness World Records also recognized the world record for the oldest competitive wakeboarder, set by Linda Brown, aged 63 yr 227 days when she competed in the Battle of Bull Run Wakeboard Tournament, Smith Mountain Lake, Virginia, United States.
Awarded an MBE for his charity work over 35 years, he was also sent a letter by Prince Charles congratulating him on his previous triathlons and wishing him luck in future races.
Mr Gilbert, currently in training for his next triathlon in April when he will be aged 91, started running in earnest during the 1980s but has entered races since the 70s.
The granddad, from Burnham-on-Sea, Somerset, attributes his extraordinary stamina to living a stress-free life, giving blood - and eating lots of bananas.
'The secret is staying stress-free, being happy, doing charity work and being positive.
'I don't drink or smoke and have regular check-ups. I also have a very balanced diet with lots of fruit for breakfast which helps tremendously - I love nuts and bananas.
'Some of it is down to giving blood. The old blood goes out, the new comes in to replace it and rejuvenates you.
'I've donated 45 pints of blood altogether since I was 51 and only stopped because I reached the age limit. People think it decreases your performance in life but it doesn't.
The 90-year-old does find some time to take it easy - despite going to the gym three times a week, cycling 25 miles on Sundays and swimming 50 lengths of his local pool every day.
'I have to work really hard at keeping fit. Being disciplined and going out and doing it even when you don't feel like it is the key to success. 'The training is the hardest part and it's almost a relief at the finishing line.'