Leanne Hainsby Says Her Mindset During Breast Cancer Treatment 'Is Totally Within My Control'

Leanne Hainsby at the World Premiere of "NO TIME TO DIE" at the Royal Albert Hall on September 28, 2021 in London, England. (Photo by John Phillips/Getty Images for EON Productions, Metro-Goldwyn-Mayer Studios, and Universal Pictures)
Leanne Hainsby at the World Premiere of "NO TIME TO DIE" at the Royal Albert Hall on September 28, 2021 in London, England. (Photo by John Phillips/Getty Images for EON Productions, Metro-Goldwyn-Mayer Studios, and Universal Pictures)

John Phillips/Getty

Leeane Hainsby is navigating life after sharing news of her breast cancer diagnosis.

On Instagram Sunday, the British Peloton instructor, 35, gave an update on her mental state since revealing her health news in January.

"One of my (incredible) cancer nurses told me just after I was diagnosed that 'cancer is as much of a mental game, as it is physical,'" Hainsby, who was diagnosed in August, wrote to her 381,000 followers.

"The conversation was had in such a blurry, terrifying time, and yet it has always remained a crystal clear moment to me," she continued. "It ignited a mindset in me that has felt like my superpower ever since."

"The apprehension I felt ahead of posting publicly about my diagnosis was pretty sky high," she said. "I knew I was ready to share, and I hoped by doing so I could raise awareness and make a difference somehow, but going from just my closest friends and family knowing, to a lot more people knowing, felt daunting."

RELATED: Peloton Instructor Leanne Hainsby, 35, Reveals Breast Cancer Diagnosis in Instagram Post

Leanne Hainsby
Leanne Hainsby

Leanne Hainsby/Instagram

Right after she shared the news, the fitness guru said that she and her fiancé Ben Alldis, a fellow Peloton instructor, sang "I'm Coming Out" and then went off to "Dopamine Land - An exhibition that boosts your happy emotions. Perfect!"

"The reason I say all this is: We chose happiness on an otherwise massively daunting day, and it felt freeing. There's been SO much that I have had little control over, but mindset is totally within my control," Hainsby said, adding:

"It's an inside job, it makes such a huge difference to how you approach anything in life, and it's well worth working on," she said, concluding her post alongside a carousel of photos and videos at the immersive multi-sensory experience, surrounded by neon lights and intricate visual designs.

Hainsby first revealed she was diagnosed with breast cancer in a lengthy Instagram post on Jan. 27.

"Two days before my best friend's funeral, I found a lump in my breast," the British spin instructor began, as she detailed her story alongside a collection of hospital room photos. "That really is a sentence I NEVER imagined writing."

After first being dismissed by a doctor who said she was fine, she went on to consult another physician and was diagnosed with breast cancer in August 2022.

"I trusted my gut and got a second opinion," she wrote. "That saved my life. Check, and check again."

Before she underwent chemotherapy, she and Alldis, to whom she has been engaged for two years, did a round of IVF.

RELATED: Peloton Instructors Ben Alldis and Leanne Hainsby Get Engaged During Romantic Trip to Ibiza

"We weren't mentally prepared, but we got it done and we're so grateful," she posted.

She was able to continue working throughout her breast cancer treatment.

"As a Peloton instructor, a huge part of my role is about the members, and despite my diagnosis, that has always mattered to me hugely. My classes have given me a focus, and some sparkle in an otherwise incredibly tough time, so thank you to the members who had no idea the amount of joy they were bringing to me every day."

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She detailed her schedule now that she has completed 12 weeks of chemotherapy.

"I would teach my Wednesday morning LIVE classes, and then meet my Mum and go to the treatment suite for my weekly dose ... Chemo is no joke. Cold caps are no joke," she wrote.

As for what her near future is looking like, "treatment will continue for a "long time for me, hospital visits are the norm."

Fortunately, she says her prognosis looks good.

"I'm in fantastic hands, and I've got this," she wrote. "Nobody wants to be sat in a room and told they have cancer, and yet I've always felt one of the lucky ones. I am one of the lucky ones. Lucky to be diagnosed early, lucky to be moving fast through treatment, lucky to know I WILL BE OK."