Super-active Bill Root reached the birthday milestone on Tuesday, May 21 and celebrated with a surprise party arranged by the judo club where he teaches 20 students once a week.
The grandfather-of-one first took up the martial art at 29 and has been teaching it for 59 years.
Now a 6th Dan judoka - an instructor who is six degrees above a standard black belt - he wears a red and white belt which highlights his superiority.
After having his own club for 30 years, Bill now teaches the seniors, aged 50 to 60, at the Leeds-based Ichiban Martial Arts Dojo, training them to coach.
In each hour-and-a-half long session every Wednesday he can be seen arm locking and choking opponents, throwing them to the floor and holding them into submission.
Widower Bill, from Keighley, said: "Judo is something you get into and you can't leave it alone. I will never stop practising and learning."
The father-of-two, originally from London, also has a rowing machine in his garden, where he works out daily.
He said: "I'm on my own. My wife, Betty - who suffered from Alzheimer's - died seven years ago - so I have to keep on top of the housework and cook from scratch every day, I have at least four or five servings of veg with every meal.
"Sprouts are definitely my favourite.
"I also look after my three-year-old granddaughter, Chloe, every Wednesday and have done since she was born.
"I am constantly busy, both mentally and physically."
Retired textile worker Bill has always been active, taking up boxing as a 15-year-old, competing in local galas and then in the army after he was called up for National Service at 18 in 1947.
He was a big squash and badminton fan and had been running football and rugby clubs in education until he was coaxed into joining a friend at judo at 29-years-old.
He opened his own school in Keighley at 31 and has been popular in judo circles ever since.
His popularity has even seen him have stints as a bodyguard and personal trainer over the years.
Bill, who moved to the north after the London Blitz in 1941, has been a 6th Dan for eight years, with ideas of progressing to 7th Dan in the future.
As well as coaching, Bill, who still drives and has 20/20 vision, also referees and present medals at tournaments.
He said: "Judo interprets as 'the gentle way', but it is not very gentle, although it is about discipline, strength and balance.
"It has definitely helped keep me fit and active. I never consider my age when I do anything. I just get stuck in and if I can do it, I will.
"Age is not a barrier, it's a person's own thought of the limits of age that is."
Owner of Ichiban Martial Arts Dojo, Bob Jones, said: "Bill loves judo, he is totally dedicated to the sport.
"He is an inspiration to us all and is a great role model at the club.
"If I am as fit as he is at his age, I will be a happy man."
Judo - meaning "gentle way" - was originally created in 1882 by Jigoro Kano as a physical, mental, and moral teaching in Japan.
It is generally categorised as a modern martial art, which later evolved into a combat and Olympic sport.
Its most prominent feature is its competitive element, where the objective is to either throw or takedown an opponent to the ground, immobilise or otherwise subdue an opponent with a pin, or force an opponent to submit with a joint lock or a choke.
Strikes and thrusts by hands and feet as well as weapons defences are a part of judo, but only in pre-arranged forms and are not allowed in judo competition or free practice.