EARLY ADULTHOOD PHYSICAL-ACTIVITY AND COLON-CANCER RISK AMONG WISCONSIN WOMEN

Frequency of strenuous activity during ages 14-22 was ascertained retr ospectively from 536 Wisconsin women with newly reported diagnoses of colon cancer and 2315 controls randomly selected from Wisconsin driver 's license and Medicare beneficiary lists. Thirty-five % of cases and 34% of controls reported strenuous activity during this period of earl y adulthood. After adjusting for age, family history of large bower ca ncer, history of screening sigmoidoscopy, and body mass index in logis tic regression models, women who reported any strenuous activity were at a similar risk of colon cancer as women who did not report activity [odds ratio (OR), 1.02; 95% confidence interval (CI), 0.82-1.27); no significant decrease in risk was seen with increase in frequency of ac tivity (P for trend = 0.84). Results were similar for the right and le ft colon subsites. These data suggest that early adulthood physical ac tivity may not confer the same protective effect that has been observe d with recent physical activity.