A native Chicagoan, Charlotte Sanddal first learned to enjoy relaxing in the chilled waters of Lake Michigan.

But it wasn’t until the ripe age of 71 that she really took to the water — one determined, methodical lap after another.

Two decades into retirement, the 87-year-old Helenan now has a boxful of swimming medals, including a six-pack (four golds, a silver and a bronze) she won last month in Sydney, Australia, at the 2009 World Masters Games.

Swimming isn’t just a hobby for Sanddal — it’s her routine, her way of life. She builds her endurance on summer mornings in the old Memorial Park pool and continues swimming daily through the winters at Crossroads Fitness Club. She’s been to numerous state masters games in Montana, Idaho and Wyoming, and an earlier trip took her to Edmonton, Alberta, for the 2005 world contest.

Sure, the competition’s nice. But she competes for the love of it — for the feeling of slicing through the water and the joy of being with people who refuse to spend their retirement in the easy chair.

“It’s wonderful,” Sanddal said in a recent interview. “It’s camaraderie. Even though you may be competing in the same events with people, there’s a friendliness about it that probably would not be on the same level if you were younger.”

Swimming gives her energy, she added.

“As we age, we get aches and pains, and this helps alleviate it,” Sanddal said. “I don’t feel tired. I don’t feel run down. I try to eat healthy. I’ve never smoked, and I think that’s part of why I’m fortunate enough to do this.”

She does plenty to stay active. The retired social worker loves kayaking — she did an 18-mile trip on the Missouri River this fall — camping, snowshoeing and cross-country skiing. And she’d like to try her hand at sailing.

Placing first, second or third in a state seniors competition serves as a qualifier for the world masters games. Sanddal had planned to combine the Sydney trip with a large family reunion, but the sinking economy and other worries led her to cancel the trip.

Then she got a call from Down Under. A 92-year-old Aussie needed a fourth for a special relay team, and the woman had used the Internet to track down the Montanan who could fill the slot. Sanddal was old enough to help the four-person team “compete” (they were the only ones entered) in the 360-class relay, which referred to the combined ages of the participants, and she was qualified in the 50-meter butterfly.

Convinced, Sanddal traveled alone to Sydney — a daunting prospect, at first. But she found a clean city where teenagers always said “hello” and her suitcase, lost on a train, was returned complete with laptop, cell phone and digital camera.

She swam in as many as three races a day, made friends with seniors from around the world and took in some of the city’s sights. And competing alongside folks in their 90s convinced her she’ll have little excuse to skip the 2013 games in Torino, Italy. She’ll be 91.

But for now, Sanddal has a more domestic focus. She plans to attend more state seniors games, though her box of medals is getting quite hefty. She gave about 40 of them back to the Montana competition’s organizers this year.

From now on, she said, she’ll just take home the first gold she wins.

Reporter Larry Kline: 447-4075 or larry.kline@helenair.com