The article by Giovannucci et al1 points out another benefit of vigorous activity; it is associated with a slower progression of prostate cancer in men older than 65 years. The authors attribute this to possible hormonal factors. An additional mechanism might also be worth considering.
Giovannucci et al1 controlled for diabetes. However, individuals without diabetes but with metabolic syndrome have higher than average levels of glycosylated hemoglobin A1c.2 This indicates that these patients have suboptimal glycemic control and an increased tendency to form advanced glycation end products (AGE).
Ross CM. Exercise and Prostate Cancer: Running From AGE?. Arch Intern Med. 2005;165(21):2538. doi:10.1001/archinte.165.21.2538-b