Exercising better cancer control
July 06, 2016
A growing body of evidence tells us exercise can be as effective in treating cancer as chemotherapy but the physiological reason is still not fully understood. Rob Newton, co-director of the Exercise Medicine Research Institute at Edith Cowan University, says it is partly because exercise helps to prime the body’s immune system.
Exercise increases the number of natural killer cells but also the signalling between the cells and their ability to seek out cancer cells in the body. It also heightens the effectiveness of existing treatments such as chemotherapy by increasing blood flow and therefore sending drugs directly to the tumour site. “Most tumours have a dysregulated circulatory system and so their capillaries are quite random and disorganised, blood flow is low, the tumour can be quite hypoxic, low in oxygen and other nutrients — so it is difficult to target the tumour and get the poison into it,” Professor Newton says.
When we exercise, tissues that are not being used shut down and the arterioles that supply them constrict in order to deliver as much blood as possible to the working muscles. “Because of this poorly developed circulation in tumours they don’t shut down, so they don’t constrict and the result is when you exercise blood pressure goes up markedly, that’s quite healthy, and results in greatly increased perfusion and more blood flowing through the tumour,” Professor Newton says.
“But also the body’s own endogenous anti-tumour medicines, things like cytokines, will also be delivered and hit the tumour, and natural killer cells and other innate immune system cells are delivered at a much higher level to where the tumour cells are developing.”
He encourages anyone having cancer treatment to exercise immediately before or after chemotherapy to maximise its effect, if they can, with advice from an exercise physiologist.
With colleagues, he is now looking into setting up a trial where patients exercise while they were receiving a chemotherapy infusion.
“It is a good time. They can do a little bit of exercise and it will help the time to pass but there are a lot of physiological reasons why it would make the therapy go better.”
Free exercise classes for cancer patients and their carers are available for up to two years after diagnosis as part of the Cancer Council WA’s Life Now program. And don’t wait until treatment has finished. With medical clearance, people can start as soon as they begin chemotherapy. “There isn’t a bad time (to start exercising), the sooner we get people engaging in that physical activity we know they can have a better outcome,” Sandy McKiernan, Cancer Council WA cancer information and support services director, says.
In some of the research trials on exercise and its effect on cancer currently under way patients are hitting the gym immediately before or after their radiotherapy or chemotherapy.
“There is a lot of research going into ‘pre-habilitation’ — working people up to get them strong so they can endure what is to come through cancer treatment, in particular some surgeries,” Ms McKiernan says. “Our Life Now program not only gives cancer patients an opportunity to work with an exercise physiologist and have a tailored program but they meet other cancer patients and their carers and engage with our other programs and get a broader support than they might have on their own.”
Among the classes cancer patients can access through Life Now is a one-off, 12-week program run by an exercise physiologist. Each participant receives an individual program to complete within a group setting.“Before anyone commences they have an assessment by an exercise physiologist to make sure they understand any potential limitations, depending on the cancer and what treatment they have had there may be some things they shouldn’t be doing, just like if they have an injury,” Ms McKiernan says
About 500 people attend the exercise program each year, a further 500 attend other classes offered including meditation, mindfulness, yoga and tai chi. “If you can get someone through the whole course of Life Now, 12 weeks of exercise treatment, then you can see really positive outcomes and people can continue with what they have learnt and build their exercise regimen,” Ms McKiernan says.
For more information call 13 11 20 or go to cancerwa.asn.au. To find an exercise physiologist who specialises in cancer, go to essa.org.au/find-aep.
The West Australian