The United States population has a growing problem: its collective body mass index (BMI). In 2000, 56% of US adults were overweight with a rating of 25 and almost 20% were obese, with a BMI of 30 or more. Obesity has risen rapidly, increasing 61% since 1991. In the same interval, the rate of combined obesity and diabetes more than doubled, increasing to 2.9%. Besides reducing the risk for obesity, exercise is associated with a lower chance of developing type 2 diabetes. There are many other benefits, including some that are unique for women.
The American College of Sports Medicine (ACSM), the Centers for Disease Control and Prevention and the American Heart Association advocate exercise. The ACSM recommends moderate intensity aerobic exercise most days of the week, coupled with resistance training twice a week. The daily goal of burning calories in 30 to 40 minutes can be accomplished in several exercise sessions, including such activities as brisk walking.
The cardiovascular benefits of regular exercise include increased HDL levels (good cholesterol) and lower blood pressure. Regular exercise reduces the risk of colon cancer. In addition to reducing the risk for diabetes, regular exercise reduces the mortality rate more than four-fold, from 40 per 10,000 woman-years in relatively inactive women to 9 per 10,000 woman-years in the women who are most active. Exercise also is associated improved mental performance, concentration, self-esteem, self-confidence, sleep quality and mood.Here’s how regular exercise has found to benefit these groups of women:
High school and college age students who participate in sanctioned sports activities have lower rates of pregnancy, drug abuse, and depression; female student athletes also have higher self-esteem scores and are more likely to graduate from high school than non-athlete peers. Young women who exercise regularly may benefit from an amelioration of symptoms related to the menstrual cycle, including a decrease in pain, anxiety, fatigue, and depression.
Pregnant women who exercise regularly generally can continue their habits during an uncomplicated pregnancy, with the bonus of specific additional benefits, including improved exercise potential (measured as a 10% increase in maximal oxygen consumption during the third trimester). Subjectively, women who exercise during pregnancy report improved pain tolerance, a shorter post-partum recovery, and a better self-image. In a study of exercise during pregnancy, active women have shown 25% lower total weight gain and less than half the fat mass gain of sedentary control subjects. However, exercise during pregnancy has not proven to shorten labor or increase the likelihood of vaginal delivery.
These benefits of exercise during pregnancy accumulate without any clinically significant associated maternal or fetal risk. Moderate exercise may acutely increase the frequency of uterine contractions in women with term pregnancies, however exercise during pregnancy does not increase the risk for miscarriage, preterm labor, or premature rupture of membranes. Lack of exercise may increase the risk for pregnancy complications. Five-year follow-up after pregnancies including maternal exercise also shows no negative impact on neonatal mental or psychomotor development.
Menopausal and post-menopausal women who exercise tend to experience a reduction in the number of falls, improved mental health, reduced cardiovascular disease, improved glucose tolerance, and reduced painful symptoms of arthritis. Physical activity is necessary for maintaining normal skeletal development, muscle strength, and joint structure and function. However, it remains unclear whether physical activity can reduce the rate of bone loss in postmenopausal women in the absence of estrogen replacement therapy.
Excerpted from Steven R. Allen, MD, Department of Obstetrics and Gynecology, Scott &White Memorial Hospital and Clinic, 2401 S 31st St, Temple, TX 76508 South Med J 94(12):1143-1144, 2001. © 2001 Southern Medical Association
