But that's what the centenarian is as he attempts this afternoon to break three world records in the 100-104 age group at the Manitoba Masters Swimming Championships at the Pan Am Pool.
"I wasn't expecting to go into the provincials, I didn't plan on it, but they twisted my arm," says Timmerman, who turned 100 on Feb. 11. "I'm anticipating and hoping I will break some records. That'll be something. They've put me in three events and I'm hoping that I can break three world records.
"It would be some achievement, anyway."
Timmerman has won so many medals at World Masters Games and other events that he's lost count and given many of them away to family and friends. He has set world records many times over and had his own records broken.
The records come and they go, but Timmerman's nothing except steady.
"I broke one record and then a fellow from Japan came along and beat me in six months time, he broke that record," said the gentle, slight man who'll be feted on Sunday in what he calls a big affair. "But we'll try. We'll see what happens on the day."
Timmerman will be competing at the Canadian Masters Championship in Etobicoke, Ont., next month. He was hoping to compete at the World Masters Games in Sydney, Australia, in October. But his wife, Gladys, has suffered a stroke and he doesn't want to be away from her for three weeks.
His son and daughter have been good about taking him to visit her in hospital but her absence has been a drain on him and "being in this apartment all by myself is no fun. It's a difficult time."
Still, Timmerman swims laps almost every day in keeping with a regimen that he feels has been the key to his longevity: good genes, healthy eating, exercise and simply living smart. He says he doesn't plan to ever stop swimming.
"It's crossed my mind occasionally but then I say to myself, what sense is there to that, because if you continue, it'll be good for your health. I don't know, I guess I'll be continuing until I die."
Paul Boulding, meet manager for this weekend's event and the man who established masters swimming in Manitoba back in the 1970s, calls Timmerman his hero. The closest in age to Timmerman of the roughly 65 competitors at the event are in their early 80s.
There are about 12,000 masters swimmers in Canada. They can be as young as 18, but the age group system starts at 25 and goes all the way up to 105-109.
"Jaring's going to be racing first of all against every single Canadian in his age group, which in his case happens to be no one," Boulding said. "There's nobody now at this point over 100 in the country. In the world, there's a handful of them, but there are existing world records for the age group 100-104."
Timmerman will be swimming in the 50-metre backstroke, the 100 freestyle and the 50 freestyle relay. The current record for the 50 free in his age group is two minutes, 6.66 seconds; for the 100 free it's 4:32.29 and for the 50 back the mark is 2:02.52.
Timmerman's practice times are about 50 seconds faster in the 100 free and about 15 seconds faster in the 50 back.
"It is, for most people, a life-long passion," Boulding said. "Jaring has been touched, somebody up there is saying 'Hey, keep going.' At the meet, I'll be very surprised if he doesn't get a standing ovation because of his accomplishments."