SoulCycle Master Instructor Stacey Griffith Shares How Fitness Helped Her After Hitting Rock Bottom

Stacey Griffith has been teaching at SoulCycle for 11 years, becoming a senior master instructor and even going on a motivational tour with Oprah.

But Griffith didn’t always lead a health-conscious life. In her new book, Two Turns from Zero, she reveals that she struggled with self-confidence, which led to her to drink excessively, do drugs and party.

“It was self-doubt and fear,” Griffith, 49, tells PEOPLE of what led her to rock bottom. “I had a lot of fear of failure. I had that voice in my head. My whole life I thought, I didn’t finish college so I was never going to succeed.”

Even when she was battling her demons, Griffith says exercise was a constant force in her life.

“I always had fitness,” she says. “The stumbling block is usually, how do you get off the couch? How do you leave the house? I need to bring this back to fitness because fitness will heal you. I focused on my fitness. I got certified on every single aspect of the body, every class, I’m certified on six different bikes. I had that confidence and I had the knowledge. Knowledge really is power.”

Griffith decided to share her personal story in her book, which also includes fitness advice, nutrition counseling and meditations, because she wanted readers to be able to relate to her journey.

“I wanted people to get to know me,” she says. “I wanted to have that personal story because it took a lot for me to get here. This did not happen overnight. This is years of discovery, and going from A to Z and getting a little tripped up on the initial letters. I just pulled it together, and the book is all about how you can pull together.”

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Griffith truly believes that fitness can be healing for anyone that embraces it.

“My book teaches people how to manifest the things they want in their life through exercising,” she says. “If you don’t have a SoulCycle in your community, you have a YMCA, you have a community center, you have a hike, you have a lake. You have to go out and you have to move.”

She also emphasizes the importance of surrounding yourself with a supportive network, and not being afraid to ask for help.

“You have to have your squad,” says Griffith. “If you don’t have a group around you that’s giving you positive motivation and good advice, then you have to change your squad.”

Griffith also believes small steps can lead to major progress, and emphasizes the importance of focusing on the bigger picture.

“It starts with purpose,” she says. “Write down affirmations, make lists of what you have to do to get your head on straight, things as simple as ‘Walk’ and ‘Call your mom.’ “