In 1980 Karen Voight was one of the most popular instructors in Los Angeles, if not the country.
After almost forty years, she is still at it.
"So I've been doing it every day - never taken a day off since," Voight said.
And it shows. Students like Hank Keilly have been with her along the journey.
"I love coming into a group class and being energized by the group. Try and do it as often as you can and diversify," Keilly said.
Most know staying active has a lot of benefits, but a recent study found that people in their 70s who have exercised consistently are biologically 30 years younger than their chronological age.
While the researchers were looking at muscle and cardiovascular health, it was important to note that these people had overall health benefits. And they were actually better than those in their 20s.
Researchers found aerobic capacities fared better in the older group than those in their 20s, but note that genes, lifestyle, diet and even income may contribute to health factors. The study did suggest the benefits to staying active.
"The main thing I tell people is just don't quit completely. If you have to ease off it, get back into it. Do what you can, work around your injuries," Voight said.
Cross training is certainly a plus.
"Those who stay with it are with it," said Bay Club trainer Marc Natividad.
Natividad is in his 50s and wants his clients to know it's not worth giving up on fitness.
"They start getting sore, there is atrophy, they're not sleeping and they are in pain," he said.
For those who need some inspiration to get to it?
"I think if they were to look at people who are in extraordinary shape that alone inspires me," Natividad said.