GUEST BLOG: Physical activity and cancer
Published 17 Feb 2017
Our guest blog is by Dr Stephen Gilbert of Northumbria University, who, along with Professor John Saxton, is investigating the advice people being treated for cancer are receiving about physical activity after their diagnosis. Dr Gilbert is inviting Breast Cancer UK supporters to take part in an on-line survey (see link below).
There is growing evidence to support the role for physical activity in the prevention and management of breast cancer. We have reviewed some of this evidence below to highlight some of the new research in this area.
Physical activity and the risk of developing breast cancer
It has been shown that by being more physically active we can reduce the chances of developing breast cancer. An international study of physical activity and breast cancer risk reported that regardless of race, body composition, menopausal status or family history, there is a protective effect of being physically active (1). Compared to women doing less than 30 minutes of activity per week, those meeting the physical activity guidelines (150 minutes per week of moderate intensity physical activity) had their risk reduced by around 35%.
These findings agree with those presented in a meta-analysis which pooled the results of 31 studies on exercise and breast cancer risk and again reported a protective effect of physical activity (2). It was found that there was a dose-response relationship between the volume of physical activity and the risk of breast cancer with women who were taking part in higher amounts of activity benefiting from greater reduction in risk.
This does not mean that everyone needs to be running marathons however, as Wu and colleagues reported that increasing activity of any kind was beneficial. They found that the risk reduced by 3% for every 4 hours per week spent walking at 2 miles per hour (a comfortable walking pace) and by 5% for every 2 hours per week spent engaging in moderate or vigorous physical activity (less than the amount of activity recommended in government guidelines).
Physical activity after diagnosis
For those that have had a breast cancer diagnosis, research shows on-going benefits of maintaining a physically active lifestyle. A recent review looking at the effects of exercise for women who have had a breast cancer diagnosis pulled together the findings of 33 studies and found that taking part in exercise led to greater muscular strength, better control of body weight and reductions in blood-borne markers associated with the development of diabetes and other cardiovascular diseases.
Furthermore, it was reported that women participating in exercise experienced reduced symptoms of depression, less anxiety and had improvements in their overall quality of life (3).
The benefits of activity don’t stop there however, as activity can also influence the chances of cancer reoccurring and overall survival. It has been shown that the chances of cancer recurrence, disease progression or new cancer development can be reduced by more than 20% through participating in physical activity (4).
Furthermore, by meeting the physical activity guidelines, breast cancer survival can improve by more than 30% in comparison with women who have the lowest levels of physical activity (5). If these findings weren’t already impressive enough, it has also been found that it is never too late to become more active. While all women engaging in activity have been shown to have improved survival in comparison to those doing nothing, the greatest benefits have been seen in those who increased the amount of activity they did after their diagnosis.
Investigating advice on physical activity given after a cancer diagnosis
Despite the growing evidence of benefits of physical activity, little is known about how any advice about physical activity gets to people who have previously had a cancer diagnosis. As part of a research study at Northumbria University we are therefore trying to find out what information about physical activity people are receiving, where information is coming from, and whether the advice being given is meeting the needs of those receiving it.
To do this we have designed a short survey to give people diagnosed with cancer the opportunity to provide information about their experiences. If you have previously had a cancer diagnosis we would be very grateful if you could complete the survey. The more people who take part, the better understanding we can get about how advice about physical activity is given out.
The survey can be reached here. The survey should take 5-10 minutes to complete. Taking part in this survey is completely voluntary and any information provided would be kept completely anonymous so it could not be traced back the person who has provided it.
While we unfortunately cannot make any guarantees of the effects of exercise on cancer risk, the research in this area shows that becoming a bit more active can be of benefit both before and after a breast cancer diagnosis. And, if the evidence above has not yet convinced you of the benefits of activity, just remember that not only can exercise be good for you, but it can also be fun.
Don’t forget however, if you are thinking about becoming more active but have any concerns about your current health, it’s always worth checking with your doctor before you start.
If you would like more detail about the survey or any of the information given above please feel free to contact me via firstname.lastname@example.org.
Dr Stephen Gilbert
Ratnasinghe, L.D., Modali, R.V., Seddon, M.B. and Lehman, T.A. (2010). Physical activity and reduced breast cancer risk: A multinational study. Nutrition and Cancer, 62, 425-435.
Wu, Y., Zhang, D. and Kang, S. (2013). Physical activity and risk of breast cancer: a meta-analysis of prospective studies. Breast Cancer Research and Treatment, 137, 869-882.
Zhu, G., Zhang, X., Wang, Y., Xiong, H., Zhao, Y. and Sun, F. (2016). Effects of exercise intervention in breast cancer survivors: a meta-analysis of 33 randomized controlled trials. OncoTargets and Therapy, 9, 2153-2168.
Lahart, I.M., Metsios, G.S., Nevill, A.M. and Carmichael, A.R. (2015). Physical activity, risk of death and recurrence in breast cancer survivors: A systematic review and meta-analysis of epidemiological studies. Acta Oncologica, 54, 635-654.
Ammitzbøll, G., Søgaard, K., Karlsen, R.V., Tjønneland, A., Johansen, C., Frederiksen, K. and Bidstrup, P. (2016). Physical activity and survival in breast cancer. European Journal of Cancer, 66, 67-74.