Tuesday, August 2, 2011
EXERCISE PREVENTS DISEASE
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.
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.
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.
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.
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).
IDEA Fitness Journal, Volume 5, Number 3
Early Weight Gain Leads to Disability
by Ryan Halvorson
As people age, the potential for mobility limitation and the threat of disability increase. A recent study found that those who gain weight early in life may be at greater risk for problems with mobility in old age than those who maintain lower weights in their younger years. Published in the April 15 issue of the American Journal of Epidemiology (2009; 169 , 927–36), the study focused on the body mass index (BMI) of 2,845 adults aged 70–79 years.
The researchers determined each participant’s BMI at various stages in life and then applied mobility tests (ability to walk one-quarter mile or climb 10 steps) semiannually over 7 years of follow-up. According to the results, those who carried extra weight early in life were far more likely to have difficulty performing the mobility tests, even if the weight had been lost subsequently. Mobility limitations were even greater in those participants who were still overweight or obese. “Over the past couple of decades there has been a trend towards declining rates of physical disability in older adults,” stated lead study author Denise Houston, PhD, RD. “However, the dramatic increase in overweight and obesity in the United States may reverse these declines and may lead to an increase in physical disability among future generations of older adults.”
“From a purely morphological standpoint, the more the person’s mass, the more stress is put through the system,” states Michol Dalcourt, a fitness educator based in Del Mar, California. “The more stress on the system, the more fascia is laid down in an effort to make the structure more stable.” This extra fascia can impede joint mobility, he adds. If you experience weight-related mobility issues, Dalcourt suggests placing efforts on safely increasing range of motion through mobility exercises “that ‘set’ the fascia to a new position. An individual, as part of an active warm-up, must perform mobilization exercises for the foot, ankle, hips and thoracic spine. This will ultimately take pressure off of the knees, low back, neck and shoulders.” For those who currently carry extra weight, Dalcourt believes a two-pronged approach—range of motion improvements and fat loss—is the safest, most effective method for achieving success.
Fresh Berries Glazed With Balsamic Vinegar
by Diane Lufshult
Here’s a quick, healthy dessert to try while the berry harvest is still in full swing this summer. Once reduced, the balsamic vinegar glaze becomes sweet and syrupy, a perfect yet unexpected partner to the fresh raspberries and blackberries used in this recipe. You can also use strawberries, huckleberries or blueberries or whatever is in season locally.
4 tablespoons balsamic vinegar
2 teaspoons (tsp) agave nectar
1 cup fresh raspberries
1 cup fresh blackberries
1/2 tsp chopped fresh mint (optional)
Pour vinegar and agave nectar into small saucepan, and bring to boil. Cook mixture until reduced by half (about 3 minutes), stirring constantly. Remove from heat. Combine berries, and place half onto two salad or dessert plates. Drizzle half the vinegar/nectar mixture over each plate. Garnish with chopped mint, if desired. Makes two servings.
Per Serving: 100 calories; 0.8 gram (g) fat; 2 g protein; 22 g carbs; 9.5 g fiber; 0 milligrams (mg) cholesterol; 8 mg sodium. Source: Adapted from The Great American Eat-Right Cookbook by Jeanne Besser and Colleen Doyle (American Cancer Society 2007).