(NewsNation) — Joan MacDonald went from struggling to do things in her daily life like walking up stairs to being a fitness influencer with more than 1 million Instagram followers while in her 70s.

MacDonald’s transformation began five years ago; her breaking point came when she needed to increase her medication again, Women’s Magazine reports. She was also struggling with high cholesterol and acid reflux.

“I was just tired of being that person who was always tired — huffing and puffing all the time,” MacDonald said. “I just didn’t like the life I was living.”

Her daughter, Michelle MacDonald, who is a fitness coach, challenged her to make changes to her diet and exercise to improve her quality of life.

“I actually put my health in my daughter’s hands,” she said. “It’s a whole thing about eating properly, sleeping, hydrating, meditating. All these things rolled together in a new lifestyle.”

MacDonald’s message to others who may be unhappy in their life is to simply “change it.”

“If you are that disappointed with your life, do like I did, just take a hold of it and change it. Get a coach if you have to. It doesn’t have to be for a long time; it’s just to get you started,” she said. “It wasn’t just being big, it was not being mobile. Not being able to do what I wanted to do.”

MacDonald authored the book “Flex Your Age: Defy Stereotypes and Reclaim Empowerment”, which inspires people to take control of their health.

“The book gives you a little bit of background about Michelle and I, plus it gives you a reason why you should even entertain this idea of getting stronger as you get older.”