Methods:  A prospective cohort of 45 887 men aged 45–79 years was followed up from January 1998 to December 2007 for prostate cancer incidence (n=2735) and to December 2006 for its subtypes and for fatal (n=190) prostate cancer.

Results:  We observed an inverse association between lifetime (average of age 30 and 50 years, and baseline age) total PA levels and prostate cancer risk. Multivariate-adjusted incidence in the top quartile of lifetime total PA decreased by 16% (95% confidence interval (CI)=2–27%) compared with that in the bottom quartile. We also observed an inverse association between average lifetime work or occupational activity and walking or bicycling duration and prostate cancer risk. Compared with men who mostly sit during their main work or occupation, men who sit half of the time experienced a 20% lower risk (95% CI=7–31%). The rate ratio linearly decreased by 7% (95% CI=1–12%) for total, 8% (95% CI=0–16%) for localised and 12% (95% CI=2–20%) for advanced prostate cancer for every 30 min per day increment of lifetime walking or bicycling in the range of 30 to 120 min per day.

Conclusions:  Our results suggest that not sitting for most of the time during work or occupational activity and walking or bicycling more than 30 min per day during adult life is associated with reduced incidence of prostate cancer.

British Journal of Cancer (2009) 101, 1932–1938. doi:10.1038/sj.bjc.6605404 www.bjcancer.com
Published online 27 October 2009

A prospective study of lifetime physical activity and prostate cancer incidence and mortality
N Orsini1, R Bellocco2, M Bottai3, M Pagano4, S-O Andersson5, J-E Johansson5, E Giovannucci6 and A Wolk1

1Division of Nutritional Epidemiology, The National Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
2Department of Statistics, University of Milano-Bicocca, Milan, Italy
3Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
4Department of Biostatistics, Harvard School of Public Health, Harvard University, Boston, MA, USA
5Department of Urology, University Hospital Örebro, Örebro, Sweden
6Department of Epidemiology, Harvard School of Public Health, Harvard University, Boston, MA, USA
Correspondence: Dr N Orsini, Division of Nutritional Epidemiology, The National Institute of Environmental Medicine, Karolinska Institutet, PO Box SE-171 77, Stockholm, Sweden; E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it.

Received 6 July 2009; Revised 2 October 2009; Accepted 5 October 2009; Published online 27 October 2009