How often should I weigh myself when trying to lose weight?
Does waist size predict the risk of disease?
Can you be fit and fat?
What's the best way to improve the appearance of the abdomen?
Does weight training burn calories?
People sometimes say that when you lose weight and get in shape, your fat "turns into muscle." Is this true?
Do media images of fit people really have an effect on an individual's self-image?

How often should I weigh myself when trying to lose weight?

Are you one of those people who don't look at your bank balance at the end of the month because you fear you don't have any money? If so, you're living in denial. It is much better to know the truth and do something about it. The same is true about weight control. Avoiding the scale will not make excess fat go away. In fact, your weight will creep up ounce-by-ounce, pound by pound until you have a serious weight problem. Researchers from the University of Minnesota found that overweight people who weighed themselves daily lost twice as much weight as those who weighed themselves occasionally or not at all. People who never weighed themselves gained weight during the study. The study involved 1800 people on weight loss programs. People who weighed daily tended to be white, older, nonsmokers who ate less fat, had a greater history of dieting to lose weight, and had a lower current body mass index. Based on this study, it is a good strategy to weigh yourself at least once a day if you are trying to lose weight. (An exception to this advice would be if you have serious body image problems or have or have had an eating disorder; avoid any weight-related behavior that leads to an unhealthy focus on body weight or shape.)

Source: Ann Behav Med. 30:210-216, 2005.

Does waist size predict the risk of disease?

Yes. Men tend to deposit most of their excess fat in the abdomen (visceral fat) and on top of the muscles of the abdomen (subcutaneous fat), while women accumulate more fat on their hips and buttocks. Abdominal fat is deadly because it is easily mobilized and sent into the bloodstream, where it can cause arterial disease and disrupt metabolism. Waist size is one of the best and simplest measures of determining the risk of type 2 diabetes, and it is even better than body mass index and waist-to-hip ratio. In a study, men who had waist sizes greater than 37 inches increased their risk of type 2 diabetes two to fifteen times above men with smaller waists. The risk of diabetes increased with waist size. For example, a 45-inch waist was more dangerous than a 40-inch waist. Increased abdominal fat deposition also increases the risk of heart disease, stroke, some cancers, high blood pressure, high cholesterol, and blood clotting abnormalities.

Source: Am J Clin Nutr. 81: 555-563, 2005.

Can you be fit and fat?

Maybe. About 60 percent of Americans are overweight, and 25 percent are obese. Some of these people exercise regularly, some vigorously, but are still overweight. Dr. Steven Blair and colleagues from the Aerobics Center in Dallas showed that carrying a few extra pounds is okay if you are metabolically fit—as long as you exercise regularly. Overweight but metabolically fit people often have normal blood pressure, blood sugar, and cholesterol. The Nurses' Health Study from Harvard, involving more than 115,000 women, showed that regular exercise did not fully erase the consequences of excess weight. The healthiest people were thin and active. Inactivity and obesity independently increased the risk of premature death. Inactive obese women had a death rate 2.4 times greater than thin, active women, while the rate was 2.0 times higher in obese but active women. The statistics were better for women who were overweight but not obese. Inactive, overweight women had a 64 percent increased death risk, while overweight, active women had a 28 percent higher risk than thin, active women. Thin sedentary women had an increased death risk of 55 percent compared to thin, active women.

          Bottom line: It's best to be lean and active, but you get some health benefits from exercise no matter how much you weigh. And it's easier for an overweight person to increase physical activity than to lose weight through diet alone.

Source: N Engl J Med 351: 2694-2703, 2004.

What's the best way to improve the appearance of the abdomen?

As described in your text, spot reducing—performing crunches to lose fat around your middle—isn't effective. So, then, what's the best way to cut ab fat? Korean researchers showed that the best approach for losing abdominal fat is to combine a general 3-day-per-week weight training program with a 3-day per week, 60-minute per session, aerobics program. Fat loss was greater for a group that did aerobics plus weight training than for a group that did aerobics by itself 6 days per week for 60 minutes per session or a control group. The combined group (weight training and aerobics) gained more lean mass (12 pounds versus 1 pound for the aerobics-only group), and lost more subcutaneous fat (62 cc versus 21 cc) and visceral fat (93 cc vs. 86 cc).

          Having more muscle increases the calories you burn. Lean mass—or fat free weight—is the most important factor determining metabolic rate and the amount of calories you burn each day. Muscle is the main component of lean mass, so the more muscle you have, the more calories you burn each day. Weight training provides a triple-whammy for weight loss by burning more calories during the exercise than at rest; increasing calorie use by increasing metabolically active tissue; and stimulating the nervous system to release hormones called catecholamines (epinephrine and norepinephrine) that increase abdominal fat use.

Source: J Physiol Anthropol. 22: 129-135, 2003.

Does weight training burn calories?

A pound of fat contains 3500 calories. It takes 10 days to lose a pound of fat if you add a workout to your daily routine that burns 350 calories and you don't increase your food intake. University of Colorado at Denver scientists, led by Edward Melannson, found that women burned an extra 325 calories per day more when they weight trained compared to not exercising, which is equivalent to running for 20 to 30 minutes. This is another study showing the importance of weight training for fat loss. Weight training increases caloric consumption during and after exercise. It also increases muscle mass, which boosts metabolic rate further. Don't worry about gaining excessive bulk from weight training. Muscle is denser than fat, which means that it takes up less space per pound. Your waist, hips, and arms will get smaller as you gain muscle and lose fat.

Source: J Strength Cond Res. 19: 61-66, 2005.

People sometimes say that when you lose weight and get in shape, your fat "turns into muscle." Is this true?

No, although many marketers of weight loss supplements and exercise machines would like you to believe it. You cannot convert one type of tissue (such as fat, muscle, or bone tissue) into any other type of tissue.

          As you learned in Chapter 6 of your textbook, fat cells—also known as adipocytes or adipose tissue—act as tiny storage bins for nonessential fat in the body. If you consume more calories than you expend, the excess calories (no matter what their source) are stored as fat within your body's adipose cells. The cells simply become larger to hold more fat. Everyone is born with a specific number of fat cells, and the body will put more

Do media images of fit people really have an effect on an individual's self-image?

It's possible. According to a recent study conducted by the American College of Sports Medicine (ACSM), some women are sensitive to images of "ultra-fit" females that appear in many fitness magazines. This sensitivity may extend to images in other types of magazines and on television, as well.

          For this study, researchers observed two groups of college-age women as they worked out on stationary bikes. Both groups read magazines while they exercised. One group looked at magazines containing images of very fit women; the other group read magazines containing no such images. At the end of their workout, members of the first group reported greater feelings of anxiety or depression than the second group.

          Experts theorize that the idealized photos made the first group of women feel inadequate about their own bodies or their efforts to improve their fitness. Instead of motivating or inspiring the women, the images actually made them feel worse about themselves.

          The researchers also noted that the women might have not understood that advertisers and publishers often alter such images in order to attract more readers or sell more products.