When Lisa Bélanger was in Grade 11, her best friend was diagnosed with Hodgkin's lymphoma, a cancer of the lymph glands. Jane Knight was one year older, a rugby player, lifeguard and runner.
The pair spent a lot of time together, even as Jane grew sicker. "I always wondered what I could to make her life easier," Ms. Bélanger said. She bought a lot of penny candy, they had movie nights, and they often went for a swim, a run, or even just a stroll around the hospital hallways before or after chemotherapy.
"What I noticed is she always felt better when she did something active. Exercise always lifted her spirits," Ms. Bélanger said.
But Jane had an aggressive form of cancer and died at the age of 19.
Losing her friend devastated Ms. Bélanger and left her questioning her own mortality. She threw herself into cancer fundraising and into sport.
She shaved her head for cancer, ran for cancer, did penny drives for cancer. "It's the way I grieved," she said.
Ms. Bélanger also graduated from high school and went on to do a degree in human kinetics and psychology at St. Francis Xavier University. For her thesis, she wrote a paper on the body image of children with cancer.
As part of her research, she e-mailed Kerry Courneya, a professor at the University of Alberta in Edmonton and Canada Research Chair in Physical Activity and Cancer. He encouraged her to take the research further and she did, embarking on a master's degree in physical activity at the U of A, and now a doctorate, focusing on the impact of physical activity on cancer.
There is already some fascinating data in this field, most of it related to prevention.
A study published in June in the medical journal Cancer found that women who are active two hours daily, five days a week, see their risk of developing breast cancer fall by about 30 per cent. (Note that this is activity – walking, grocery shopping, yard work – not exercise in the gym.)
Earlier research, published in the Journal of the American Medical Association, found that women who increased their activity levels after being treated for breast cancer saw their risk of recurrence drop by half. That study focused on exercise, but showed that a mere 30 minutes daily of moderate activity (such as brisk walking or biking) provided dramatic benefits. It also showed that fewer than one-third of breast-cancer survivors were even minimally active.
There are a number of studies that examine the specific benefits of exercise to subgroups, such as women in their reproductive years and postmenopausal women – and there can be significant differences.
Canada has long been a leader in this field. Research done by Christine Friedenreich, an epidemiologist at the University of Calgary, way back in the 1990s showed clearly that women who exercise routinely during their lifetime cut their breast-cancer risk by at least one-third; those who did not smoke or drink alcohol in addition to being physically active saw their risk plummet by 70 per cent, showing the cumulative impact of reducing risk factors.
The take-home message here is the same one that Ms. Bélanger understood as a high-school student reaching out to a friend: Exercise is one of the cheapest, most effective methods we have for preventing and treating breast cancer (and cancer more generally). It is also grossly underprescribed. (Research has shown that actually having doctors write a prescription for exercise is one of the best ways to get people to break a sweat.)
While we know exercise helps, there is still much to learn. For example, it is not yet clear what the best dosage is to get the maximum benefit.
So, these days, Dr. Courneya and Dr. Friedenreich have teamed up to tease out that key information. They are following two groups of women, one who will be active 300 minutes a week and another 150 minutes a week of aerobic exercise, to see which has the greatest reduction in breast-cancer risk.
What research tells us so far is that, for survivors, vigorous exercise is better. It may be true for prevention too.
Ms. Bélanger, for her part, is working with young cancer patients, measuring the impact of exercise on their their treatment and recovery. "We make the mistake of thinking that people with cancer are sick so they can't do anything. It's not true," she said.
The gym provides social support and an outlet for stress. In early results, Ms. Bélanger is finding that patients who exercise actually have better outcomes from chemotherapy, mainly because they are more likely to stick to the treatment.
The other important aspect of her work is figuring out how to communicate with patients, the psychology and the nitty-gritty of how to encourage them. So far, the message is: Simpler is better.
Give the patients a written plan (or a prescription), give them evidence that exercise will help, provide them with a place to work out and give them encouragement.
Some of the patients in her study have become so keen on exercise that they have formed teams to participate in the Walk for the Cure (for breast-cancer research) or run with Team in Training (a fundraiser for the Leukemia & Lymphoma Society).
"These walks and races give me the chills because the participants are so alive," Ms. Bélanger said. "They really show me the power of exercise as medicine."
They also show the power of honouring a friend, of taking from tragic loss inspiration for a life's work.