Exercise's Effects on Other Conditions

Exercise's Effects on Other Conditions

Effect of Exercise on Cancer

A number of studies have indicated that regular exercise may reduce the risk of breast, prostate, and colon cancer. Exercise not only lowers a woman's chance of getting breast cancer, it can help those who have received chemotherapy for the disease fight off fatigue. 

A 2004 study showed that prostate cancer cells have a 27% reduction in growth when exposed to exercise serum (blood serum taken from patients who exercise) compared to control serum, suggesting that exercise changes blood chemicals to be less hospitable to cancer cells.

Physical activity has been said to lower a man's risk of colon cancer, but data linking exercise to a lower risk in woman has been inconsistent. A 2006 study published in the International Journal of Cancer concluded that exercise may not reduce a woman's risk of colon cancer. Previous studies, including the Nurses Health Study and the American Cancer Society's Cancer Prevention Study II, found that exercise reduced a woman's risk of colon cancer by 30-40%. The prospective cohort study involved nearly 32,000 mostly postmenopausal women who were participating in a breast cancer trial. The women were given questionnaires and asked to rank their exercise habits according to light, moderate, and heavy activity. The study author says the conflicting result may be due to a misclassification of certain activities.

Effects on the Gastrointestinal Tract

Endurance athletes often report stomach problems, such as bloating, diarrhea, and gas, even at rest. Experts suggest that moderate regular exercise, might reduce the risk for some intestinal disorders, including ulcers, irritable bowel syndrome, indigestion, and diverticulosis. Older people who exercise moderately may have a lower risk for severe gastrointestinal bleeding.

Effects on Kidney Disease

Patients with end-stage kidney disease who exercise four to five times per week have better survival rates than those who are less active, researchers involved in the Dialysis Morbidity and Mortality Wave 2 study report. However, the majority of study participants said that severe physical limitations that prevented them from exercising that often.

Effects on Neurologic Diseases and Mental Decline

Studies have shown that regular exercise, particularly walking, helps reduce one's risk for memory loss. A 2005 study found that older men who walked less than a mile daily had a 71% higher risk of dementia than those who walked more than two miles a day. An earlier study found that walking regularly protects women from mental decline. To date, there are no clear theories for the apparent benefit, although a preliminary study in mice suggests that physical activity changes the way brain-damaging proteins are metabolized in the brain, thus slowing the development of Alzheimer's disease. (Stretching and weight training appear to have no such effects.)

Aerobic exercise has been linked with improved reaction time, perception, and math skills in people of all ages.