Lifetime physically active men have a lower risk of developing prostate cancer, according to a new study from Karolinska Institutet (KI). The effect was observable in those who had been sitting for less than half their working day or had been physically active for more than an hour a day.
In 1997, over 45,000 Swedish men between the ages of 45 and 79 responded to a survey on lifestyles and degree of lifetime physical activity. Ten years on, the researchers have now followed up the group with respect to the incidence of prostate cancer.
The results from this prospective cohort study, which are published in British Journal of Cancer, show that a high level of physical activity correlates with a lower risk of developing prostate cancer.
Men who reported that they had been spending less than half their working day sitting had a 20 per cent lower risk of prostate cancer than those who had been sitting for most of the time. Men who walked or cycled on average more than 60 minutes a day had a 14 per cent lower risk than those who walked or cycled 20 to 40 minutes a day.
According to the researchers, this is the first time that a link has been observed between long-term physical activity and the risk of prostate cancer. However, the biological mechanism through which physical activity can affect this risk remains unknown.
’A prospective study of lifetime physical activity and prostate cancer incidence and mortality’, Orsini N, Bellocco R, Bottai M, Pagano M, Andersson’S-O, Johansson J-E, Giovannucci E, Wolk A, British Journal of Cancer, Epub ahead of print, 28 October 2009.