By Stacy Kennedy, M.P.H., R.D., L.D.N., C.N.S.D.
Brigham and Women's Hospital
Exercise and a healthy diet are essential for losing weight and helping to reduce your risk of diabetes, heart disease and certain cancers. If you are overweight, losing just 10 percent of your body weight can lead to a reduction in health risk, according to the American Diabetes Association. Physical fitness and eating well also have many immediate benefits, including improved mood; reduced stress level; regular bowel function; more energy and less fatigue; less pain; and strong, toned muscles, translating to fewer inches around your waist and hips.
For women at risk of cardiovascular disease, being fit may be more important than being at a healthy weight. Physical fitness is independently associated with lower risk of heart attack, stroke and congestive heart failure. This does not diminish the importance of maintaining a healthy weight. Overweight or obese people are more likely to have coronary artery disease risk factors such as higher blood pressure, blood sugar and triglycerides, compared to women of healthy weight. The American Heart Association guidelines for women recommend accumulating at least 30 minutes of moderate-intensity physical activity on most days of the week. Ideally, you should participate in physical activity for an hour every day.
Many people are aware of these and other hazards of being a couch potato but find it difficult to fit fitness into their lifestyle in today’s society. For many, regular exercise is not a natural part of the day as it was for many of our ancestors. We drive almost everywhere, sit at a desk for at least eight hours a day and rely on modern technology for many tasks that once required manual labor.
The good news is that physical activity, which is different than exercise, is a great place to start. Physical activity is defined as any movement throughout the day, including tasks of daily living such as housework or taking a flight or two of stairs at the office. Exercise refers to a more structured bout of activity, such as an aerobics class, hiking, cycling or swimming.
While beginning an exercise routine may seem daunting, increasing physical activity can fit easily into your day. Walking is the most popular form of exercise for Americans. Remember that every step counts. If 30 minutes is too much to do all at once, you can begin by walking for three, 10-minute sessions over the course of the day, according to the U.S. Centers for Disease Control and Prevention. Wearing a pedometer is an easy and inexpensive way to monitor your progress. On average, Americans only walk about 2,000 to 3,000 steps per day. The ultimate goal is to accumulate 10,000 steps a day, which is equivalent to 30 minutes five or more days a week. Track your current steps for one week, then set a goal to increase each week by 10 percent until you reach 10,000.
Losing weight by eating less and exercising more is the most important thing you can do to lower your risk of type 2 diabetes, if you are currently overweight or obese. Obese women, (defined as those having a BMI higher than 30) have almost 12 times the risk of developing diabetes if they are inactive, compared with active women of normal weight, (a BMI lower than 25). A study in Boston of almost 38,000 women concluded that physical fitness alone was not enough to lower the risk for diabetes when weight was considered. Losing weight by eating right and exercising was the key element for prevention. New studies show that some drugs can decrease the risk of diabetes, but they will never be a substitute for weight loss through diet and exercise.
Maintaining or achieving a healthy weight can take keeping an eye on your portion sizes as well as increasing your physical activity. If you are trying to lose weight, you want to both burn calories by exercising and eat fewer calories by following serving size guidelines found on food labels. To get an idea of how many calories are in certain foods, and what kind of activities can burn these calories, check out the Portion Distortion Quiz from the National Institutes of Health. This site is full of helpful information showing how American portions have grown in the past few decades, contributing to expanded waistlines.
Once you’re ready for a 30- to 45-minute workout, you want to be sure to fuel your body wisely so that you have adequate energy to burn and enough nutrients for focus, concentration and good old hard work. Eat a pre-workout snack one to two hours before exercise that includes a protein source and moderate to low glycemic-index carbohydrate. As some examples, try a quarter cup of nuts and a medium apple; 4 to 6 ounces of yogurt and a banana; one small to medium energy bar (at about 160 to 250 calories); or one mozzarella string cheese and a quarter cup soy nuts. Note that these portions are not large, because you don’t want to sabotage your workouts by overeating.
Hydration is essential to effective exercise and maintaining a healthy weight. Drink 8 to16 ounces of water at least 30 minutes before exercising, then 2 to 4 ounces of water every 15 to 20 minutes during your workout, and then 16 to 32 ounces right afterward. Sports drinks are needed if you are doing more than 90 minutes of continuous exercise. Otherwise, water is your best bet and a smart way to avoid excess calories.
Always check with your doctor before beginning an exercise routine, especially if you take medications; have a heart condition, diabetes or cancer; are over the age of 50; or have been sedentary for years. Exercise and eating right are important for people of all ages and can be more successful when the entire family is involved and having fun together.
Stacy Kennedy, M.P.H., R.D., L.D.N., C.N.S.D., is senior clinical dietician at Dana-Farber Cancer Care/Brigham and Women's Hospital. She completed her dietetic internship at Massachusetts General Hospital and received her Master of Public Health in Nutrition from the University of North Carolina.