AURORA, Ill.>> Ernestine Shepherd, 81, believes that exercise should be a key part of everyone’s day, including senior citizens’.

It’s a principle that Shepherd embodies as an 81-year-old bodybuilder.

Shepherd said she did not embrace serious training until about a decade ago but that she had begun working out in her mid-50s after she and her sister were invited to a church picnic “and didn’t like the way we looked in our bathing suits.”

“This exercising and training started as a result of vanity,” Shepherd admitted. “My sister Velvet was 57 at the time, and I was 56. I lost her not long after to a brain aneurysm, and I vowed to keep the promise I made over 25 years ago to continue this journey as long as I have the strength.”

Shepherd unveiled a shirt before the crowd with a message that she said epitomizes everything she does.

“I have the words, ‘Determined, Dedicated, and Disciplined to be fit’ and that encompasses everything I do,” Shepherd said. “I feel if you use your mind and follow the three Ds, you can’t fail.”

Shepherd’s personal trainer and manager, Yohnnie Shambourger, said he met his prized pupil when she was 71 and attending a bodybuilding show he was promoting.

“I remember seeing Ernestine in the audience,” Shambourger recalled. Later, she asked me to train her to compete. “She wasn’t sure she could do it.”

When they began working together, Shambourger said, Shepherd was living an hour away in Baltimore and would commute to his fitness center twice a week along with doing online video sessions.

After seven months, Shepherd’s “transformation was remarkable,” he said.

“I sent out this media blast about her, and before you knew it, there were a ton of people that wanted to interview her, and it got to be so much, she asked me to manage her,” Shambourger said.

Shepherd told the crowd she has been married for 61 years to her husband who is now 87 and that she has a 60-year-old son and a 20-year-old grandson.

“He’s very proud of everything I do, and my doing this has motivated him to be active and not wait until the last minute,” she said. “There are days when I have aches and pains, but I still run 10 miles a day and was doing marathons five years ago.”

Regina Burns, 75, said she has been encouraged by Shepherd and exercises regularly herself.

“As far as the message that age is just a number — you’re as old as you think you are, and I think she’s a wonderful model in terms of being healthy and doing what you should,” Burns said.