Peter Grandiek is training to do a bike ride from Mossburn to the Ascot Park Hotel in Invercargill on October 23.
Mr Grandiek has been doing charity rides for his birthday for the past eight years — this time he is raising money for the Cancer Society.
"It started off as a bit of a joke. We were in Alexandra for the world champs and there was a guy who said he has done 80km for his 80th birthday.
"Me, being stupid, said I would do 85km when I turn 85, and my friend who was next to me held me accountable. Since then I never stopped."
While many people slow down when they get older, Mr Grandiek has been increasing his challenge each year.
Last year for example, he rode 400 laps (100km) at the ILT Velodrome for his 90th birthday.
"From now on, after that, I think I will go down [doing less kilometres] but this will be my biggest challenge yet."
Last weekend, he did a trial run where he rode 94km in about 3 hours and 50 minutes.
He believed he would be able to complete the planned course within 5 hours, he said.
"It depends on the weather conditions. If I get a tail wind, I will go even faster than the trial run."
He decided to fundraise for the Cancer Society this year as a way to acknowledge the important work they do and thank them for their support in a recent surgery.
"Five months ago, I had to do a bowel surgery and they had to remove a tumour from that. I am doing a fundraising for them because it is amazing the skills of surgeons, and the clinical staff there."
His recovery was so good that about six weeks later, he was already on his beloved bike cycling around the town.
The secret for such energy at 91 was self-motivation and being positive, he said.
"When people said to me that I can’t do something or that I shouldn’t be doing that, it tells me the opposite — that I can do and that I will do it.
"If you sit down and just do nothing, you lose your confidence in yourself — so you just got to keep moving."
