You probably know that exercise is good
for you, but did you know that it can both improve the quality of your life and reduce the risks of developing diseases? Regularly
participating in moderate physical activity can reduce the risk of coronary
heart disease, hypertension, some cancers and type 2 diabetes.

Below, Len Kravitz, PhD, program coordinator of exercise science
and a researcher at the University of New Mexico, discusses some of the
diseases exercise can help prevent. For more information on developing a fun,
efficient exercise program, please contact a certified personal trainer or
exercise instructor.

Cardiovascular Disease

The leading health-related cause of death
for men and women in the U.S. is cardiovascular disease, according to the
American College of Sports Medicine. The good news is that higher levels of
cardiovascular fitness are associated with a 50% reduction in cardiovascular
disease (CVD) risk in men, says research by Myers and colleagues in the
December 2004 issue of The American Journal of Medicine. Plus, increasing physical activity to a total of at
least 1,000 kilocalories per week is associated with a 20% reduction of
mortality in men. What about women? Physically inactive middle-aged females who
did less than 1 hour of exercise per week
doubled their risk of mortality from CVD compared with their physically
active female counterparts, note Hu and colleagues in the December 23, 2004,
issue of
The New England Journal of Medicine.

Cancer

Exercise is connected with a lower
occurrence of colon cancer in men and women, and of breast cancer in women. In
the November 2003 issue of Medicine & Science in Sports & Exercise, Lee reports that moderate to vigorous physical
activity has a greater protective effect than lower intensities of physical
activity. Lee notes that physically active men and women have a 30%–40%
reduction in relative risk for colon cancer compared with their inactive
counterparts. It seems that about 30–60 minutes of moderate to vigorous
exercise per day is needed for this risk reduction, with higher levels of
exercise showing even lower risk. In addition, physically active women have a
20%–40% reduction in relative risk for breast cancer compared with their
inactive counterparts. It also appears that the 30–60 minutes of moderate to
vigorous exercise per day is needed to generate this level of risk reduction.

Diabetes

Elevated insulin and blood glucose levels
are involved in the development of non-insulin-dependent diabetes mellitus.
When insulin function starts breaking down, the body’s blood sugar levels rise,
leading eventually to the onset of “prediabetes” and then type 2 diabetes.
Regular aerobic exercise meaningfully increases insulin sensitivity and glucose
metabolism, which means the body’s cells can more efficiently transport glucose
into the cells of the liver, muscle and adipose tissue, according to Steyn and
colleagues in Public Health and Nutrition
(issue 1A, 2004). Improvements in glucose metabolism with strength training,
independent of alterations in aerobic capacity or percent body fat, have also
been shown, according to research by Pollock and colleagues in the February
2000 issue of
Circulation. It
appears that both resistance training and aerobic exercise offer a strong
protective role in the prevention of non-insulin-dependent diabetes mellitus.

SIDEBAR: Preventing Hypertension

Hypertension (abnormally high blood pressure) is a major health problem. Elevated systolic and diastolic blood pressure levels are associated with a higher risk of developing coronary heart disease, congestive heart failure, stroke and kidney failure. According to research by Bouchard & Despres in Research Quarterly for Exercise and Sport (volume 66, 1995), a person doubles his chance of developing these diseases when blood pressure is 140/90 millimeters of mercury (mm Hg). The good news is that in many cases, you can reduce elevated blood pressure by decreasing weight and lowering alcohol and salt intake in your diet. Moderate-intensity aerobic exercise performed 3–5 times per week for 30–60 minutes per session appears to be effective in reducing blood pressure (when it’s elevated).