At Sydney's iconic Bondi Icebergs pool, on a crisp spring morning, Siobhan O'Toole and Donna Moclair look like seasoned swimmers used to the waves crashing over them as they do laps.
Few would realise both women have been in the fight of their lives with a cancer diagnosis.
And that exercise has been their lifeline.
Siobhan had an aunt who died from breast cancer at 40, so she decided to get screened earlier than doctors recommend.
"I thought I might be high risk and unfortunately, when I was 40 they found triple negative breast cancer," she said.
Triple negative breast cancer is notoriously difficult to treat.
Always active, she got involved in a trial at Sydney's St Vincent's Hospital, which used exercise to better cope with cancer treatment.
"Exercise gave me something that I could control, it gave me something to do every day that meant I achieved something during cancer treatment."
Each week the IT consultant swam and took part in three sessions of resistance training, and every day she made sure she took at least 8,000 steps.
"I thought about [exercise] as pushing all of that chemo through my body to try and make the chemo more effective," she said.
Fellow swimmer Donna Moclair didn't know what to expect when she was diagnosed with advanced ovarian cancer.
"It came as such a shock really," she said.
Donna said she was fit before her diagnosis, but being able to keep swimming and even training for competitions during treatment was "her sanity".
"When I was swimming, I felt like the chemotherapy was being washed away. I found that really soothing, just to clean your mind and body," she said.
She even came third in a Winter Swimming Association event while having treatment.
"I just kept training and training and training. And then after it, I got fitter and I got my body back and my mind back. And I actually won the year after, which was great."
There is increasing evidence that exercise helps fight cancer
Orthopaedic surgeon Jonathan Herald says he sees how much quicker patients recover with structured exercise rehabilitation.
"Exercise is emerging as one of the most powerful weapons in the disease-fighting arsenal to combat diseases like cancer," Dr Herald said.
A recent paper found women who engaged in regular exercise before their cancer diagnosis, and after treatment, were more than 40 per cent less likely to have their cancer come back or to die from the disease, than breast cancer patients who were inactive.
And leading cancer groups want exercise embedded as part of recovery.
The Clinical Oncology Society of Australia recommends 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity exercise, such as walking, jogging, cycling or swimming, each week as part of standard cancer care treatment.
It also recommends two to three resistance exercise sessions each week.
Medical oncologist and cancer researcher Dr Sara Wahlroos is currently studying the benefits of preventing the loss of muscle mass for breast cancer patients.
For her research, she prescribed 18 women a 20-week weight-based exercise program that they took part in while undergoing chemotherapy.
She noted that most of the women were able to adhere to the program and maintain their strength, while some even became stronger.
She believes the gold standard of cancer care should involve an exercise physiologist.
"It really should be part of the system," she said.
"It should be subsidised."
Cancer patients have limited access to rehab
In Australia, people who have had a heart attack can join a six-week rehabilitation program, including exercise training, through the public hospital system.
But if you have a chronic health condition, including cancer, Medicare subsidises just five sessions with an exercise physiologist as part of a chronic health care plan from your GP.
Caroline Booth was referred to an exercise physiologist by her oncologist and did three sessions of strength training a week, as well as some lighter exercises every day.
"I feel like it has made a significant difference to my energy levels and it's become easier the more I do it," she said.
"I wish I had started it earlier, but it is very expensive."
She has had to pay the full $100 cost of each session with an exercise physiologist because she had already used up the available Medicare subsidy earlier in the year on physiotherapy for a chronic back issue.
Doctors such as Jonathan Herald believe cancer patients deserve the same access to supervised exercise rehabilitation as patients in the workers compensation system.
"To fight cancer, which impacts 1 in 2 Australians by the age of 75, we need to throw everything at it," he said.
Along with cancer researchers and clinicians, he is calling for cancer patients to be offered supervised exercise programs.
"It's not enough just to recommend to patients that they exercise. It needs to be structured and subsidised, ideally through the Federal Government."
Siobhan and Donna have joined forces with Dr Herald to produce a book called The Exercise Prescription, which draws on the latest research into the benefits of exercise.
All the proceeds from the book will go towards funding an exercise rehabilitation clinic for public cancer patients at Sydney's St Vincent's Hospital
"We don't wrap other patients in cotton wool. We know people get better and stronger if they are able to exercise," he said.
Two women sit on the edge of an ocean pool, laughing.
Donna and Siobhan want other cancer patients to get the physical and mental health benefits from exercise that they have.
"I don't really understand how if you have a heart attack or a motorbike accident or you have reconstructive surgery, you can get a freely accessible rehabilitation," Siobhan said
"For cancer patients, if they can exercise, it would really benefit them," Donna said.
"It helped me so much. I loved it."
Article from ABC News