Regular exercise linked to bowel cancer prevention
Regular exercise can significantly reduce one of the early signs of bowel cancer in men, new research has claimed
The Fred Hutchinson Cancer Research Centre study looked at the rate of new tissue growth in the tiny pockets, or 'crypts', of cells in the gut.
"A certain amount of cellular proliferation at the bottom part of the crypt is normal. But when these cells start dividing too quickly, they can migrate up the sides of the crypt to the surface and eventually form a polyp," said lead researcher Dr Anne McTiernan.
While most polyps are benign, over time some types can become malignant.
The researchers found that rate of growth slowed in relation to the amount and intensity of exercise men performed.
"In men who met the study's exercise prescription of an hour of aerobic activity per day, six days a week for a year, we saw a substantial decrease in the amount of cellular proliferation in the areas of the colon that are most vulnerable to colon cancer," she added.
"However, we found that even four hours or more of exercise weekly was enough to produce a significant benefit.
"These effects were independent of weight. Vigorous exercise was helpful for men of any size, as long as they worked out nearly every day," she added.
The effect was more pronounced among men who completed the most cardiovascular exercise. No equivalent reduction in cellular growth was found among sedentary men.
The study also did not reveal any relationship between bowel cancer and exercise among women, although the researchers noted it can be effective against other cancers.
The research was conducted with the participation of 202 healthy, previously non-exercising men and women, all of whom had had a bowel examination before the trial.
Half of the participants were assigned to an exercise group and half remained sedentary. All were asked to continue with their normal diets.
The researchers noted that the participants reported a high level of adherence to their exercise programmes, with 80 per cent completing at least eighty per cent of their goals.
The study is published in the journal Cancer Epidemiology, Biomarkers and Prevention.
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