For months Leanne Hainsby continued to teach while undergoing chemo. Photo / Instagram@LeanneHainsby

With her beaming smile and unbeatable stamina, it’s easy to assume Leanne Hainsby hasn’t a care in the world.

The British Peloton instructor is one of the fitness platform’s most-loved teachers, with thousands tuning in daily to take her pop-filled spin classes.

One of her most recent sessions sees the 35-year-old take users through a gruelling 30 minute session to a Kylie Minogue playlist. Leanne barely breaks a sweat as she battles through steep inclines and high speeds to the beats of Spinning Around and I Should Be So Lucky.

But despite her infectious “sparkly” personality, Leanne has been enduring a devastating double blow after being diagnosed with triple positive breast cancer just days after her best friend’s Danielle Hampson shock death.

“I know, more than ever, how important movement is,” Leanne told news.com.au.

“I am using my experiences and knowledge that I have gained, and am continuing to gain, to be the best instructor I can be.

“I know there will be people who have been diagnosed that will feel they can keep working out in some capacity, because I am, and that means the world to me.”

Leanne, a former dancer who has performed on stage with some of the world’s biggest stars including Taylor Swift and Katy Perry, first opened up about her health battle in an emotional Instagram post at the start of the year.

“Two days before my best friend’s funeral, I found a lump in my breast,” she wrote in January.

“That really is a sentence I NEVER imagined writing.

“After multiple scans and appointments with both consultants and cancer nurses, and being completely terrified for a few weeks, in August 2022 I was diagnosed with breast cancer.”

Danielle, who was engaged to a former X-factor UK contestant Tom Mann, died unexpectedly on the morning of their wedding in June 2022.

She was just 34 and left behind the couple’s young son Bowie.

It was while still reeling from this shock loss Leanne found a “golf ball” sized lump in her breast.

Initially doctors shrugged it off because of her age, but she pushed for tests, resulting in her diagnosis.

After revealing the news, Leanne’s 387,000 followers rallied to show their support, with many commending her for continuing to teach each week while undergoing treatment for cancer and dealing with grief.

But it wasn’t easy to keep such an “awful secret”.

“There was definitely a point, after Danielle’s death, when I thought, ‘I’m never going to be happy enough to do this job again’,” she told The Telegraph.

“But then I started to think of the Peloton members. A lot have cancer, or have had cancer, and are going through treatment.

“I knew there was power in me carrying on. Also, I was in the very early stages of grief. I had to have a focus.”

For months, Leanne – who is engaged to fellow Peloton instructor Ben Alldis – would teach a live class every Wednesday morning before undergoing chemo.

“If I was waking up and just hanging about to go and have chemo, it would have felt like chemo was taking up my whole day. Cancer would be winning,” she told the British publication.

“My classes turned out to be a haven – one moment in my day when I wasn’t a breast-cancer patient, or the girl who’d just lost her best friend. It felt like I could be free for a little while.”

Despite her determined spirit, it was becoming harder and harder for Leanne to hide the ravaging effects of the chemo from the Peloton community, prompting her to go public.

“Some people noted I was wearing less make-up, which I was – because I didn’t have any eyelashes or brows to put make-up on,” she explained.

“And I didn’t want to use fake tan during my treatment. So I wasn’t looking like my usual self.

“But by January, my nails started to die off, I’d lost all my lashes, I was really really pale, and I thought, ‘Before people start telling me I look really different I want to own it’.”

Leanne chose to use a cold cap during chemo, an ice-cold device worn to reduce blood flow to the scalp. It’s effectiveness varies from person to person but for Leanne, it help retain her signature blonde hair.

The response from her Peloton community was beyond anything she could have expected with Leanne stating it helps to know she’s inspired others to get checked out.

“I never understood the power of community until I shared my recent diagnosis,” she told news.com.au.

“The love, well wishes and support has been more than I ever thought possible.

“When I shared my news, I knew my main goal was to raise awareness. To remind people to check, and check again, and I’ve had so many people tell me they’ve booked in for check ups, or insisted on second opinions because of my news.

“That is a positive, in what has been a not so positive time.”

Thankfully, after completing a course of radiotherapy last month doctors said Leanne is now cancer-free.

She’ll be on medication for the next two years and will need to maintain regular check-ups, but “the prognosis is good”.

As a result, she’s throwing herself into work, most recently leading Peloton’s first Australian-led artist series starring Kylie Minogue, who she once performed alongside as a professional dancer.

“Kylie’s music has always been such a constant in my life. I’ve always been excited to watch her music videos and shows over the years, she always brings something new that as a performer always felt so exciting,” Leanne said.

“I truly believe music is therapy. It has the ability to boost your mood, your confidence, it can transport you to a different feeling, emotion, memory, or decade in seconds, and it brings us all together in some way.

“That, to me, is MAGIC.”

Despite her positive outlook, Leanne said “it’s important” to point out it is impossible to maintain her signature “sparkle” at all times.

“Some days are really hard, and I’ve learnt that that’s ok, and it’s how my life looks at the moment.

“However, when I show up to the studio, I am choosing happiness. I am choosing joy, and I am deciding that no matter what else has been going on that day, those 30 minutes will be sparkly and fun, and I’m going to give it my all. The sparkle is a mindset.”

It’s a sentiment not lost on her fans who continue to thank Leanne for sharing her difficult story.

“YES, as a fellow young breast cancer survivor, I LOVE that you’re spreading awareness,” one wrote on social media.

“The strength you give others on a daily basis is just a fraction of the strength you possess inside. We are beyond grateful to you,” another said.

As another declared: “You will never not be the sparkliest most beautiful person in any room! Keep fighting. You’re not alone.”

Peloton’s Kylie Minogue artist series classes are now available to take on the platform and include a mixture of walking, running, yoga and cycling sessions.