This is an excerpt from Woman's Guide to Muscle and Strength, A by Irene Lewis-McCormick.
Women's Fitness Myths
Before you begin your strength training program, you need to understand the facts about many aspects of exercise, including cardio training, flexibility, and to some extent, the role diet plays in helping you reach your fitness goals. It takes more than just lifting weights to own the ideal female physique—one that is strong, low in body fat, and high in lean mass, that provides muscle definition, and that functions well in everyday life. Some of the most common misconceptions, or myths, that women believe about exercise are covered here. The following answers to common questions provide simple, unbiased advice about exercise fads, fitness hype, magic bullets, and false promises, as well as information that every female exerciser should know.
If I want to lose weight and tone up, should I be doing more weights or more cardio?
Cardiorespiratory exercise that promotes adequate caloric expenditure is necessary for fat loss, weight management, and overall fitness. But myths about aerobic exercise and energy expenditure abound, as do those about strength training. You probably already know that to lose weight you need to address both diet and exercise. Exercise must include both cardio and strength training. Many women believe that only cardio exercise is needed to lose weight, but nothing could be further from the truth.
We will go into detail about the value of strength training for weight loss throughout this book, but let me say here that cardio exercise is a vital component to any strength training program and weight loss effort. The reason is that it ups the ante on caloric expenditure and improves the health of your heart, blood vessels, brain tissues, and other vital organs. Significant amounts of scientific evidence clearly show that cardio exercise (as well as strength training) can help prevent and manage hypertension, coronary heart disease, stroke, type 2 diabetes, osteoporosis, arthritis, stress, colon cancer, abnormal cholesterol levels, and depression (Hillman et al. 2008).
How do I know when I am in the fat-burning zone?
Perhaps the most popular myth about aerobic exercise is that there is a specific heart rate range in which you must exercise to burn fat as the primary fuel source. Target heart rate has become a buzz phrase. Many cardio machines even display a fat-burning zone on their panels, encouraging people to exercise in a specific heart rate range to burn fat specifically. Because more fat is used at lower exercise intensities, many people assume that low-intensity exercise is best for burning fat.
The truth is that we use both fat and carbohydrate (as well as some protein) for energy during exercise. These fuels provide energy as the body needs it, sort of on a sliding scale. During exercise at very low intensities (e.g., walking at a moderate pace), fat accounts for most of the energy being used. As exercise intensity increases, the contribution from fat decreases, and the contribution from carbohydrate and protein increases. What matters here, however, is the rate of energy expenditure. Where the calories come from is really not the point. When exercising at higher intensities (i.e., closer to the lactate threshold), you are burning more total calories from all energy sources. For fat and weight loss, what matters most is the difference between the number of calories you expend and the number of calories you consume. For the purpose of losing weight, it matters little whether the calories burned during exercise come from fat or carbohydrate. Fat and weight loss is really all about burning lots of calories and cutting back on the number of calories consumed.
Can I strength train to get rid of my belly fat or tighten my upper arms?
Ask any woman what her “trouble” spots are, and she will probably give you a list of all the well-known areas women like to approach through exercise, including glutes, thighs, waist, belly, and upper arms. Spot reduction is the mythical belief that fat can be lost in specific areas or muscle groups. However, fat is lost throughout the body in a pattern dependent on genetics, gender, hormones, and age. Overall body fat must be reduced to lose fat in any particular area. Although fat is lost or gained throughout the body, it seems that the first areas to get fat or the last areas to become lean are the abdominals, hips, and thighs. But, although you cannot spot reduce, you can spot train, meaning that you can strengthen a specific muscle group through aerobic activity and resistance training.
If I lift too heavy of a weight, will I get bulky muscles?
Contrary to many women's concerns, strength training using heavy weights won't result in large, bodybuilder-type physiques. However, some women still fear that it will bulk them up in unfeminine ways. Women who strive to become competitive bodybuilders work out for several hours a day using a variety of exercise techniques, and a large percentage of their training combines very heavy weight loads. Some women also take hormones and steroids to increase their muscle mass.
Muscle strength is improved primarily by increasing muscle size (hypertrophy) and the number of muscle fibers recruited. Muscles experience hypertrophy when the muscle fibers increase in size. Increases in muscle size are highly dependent on diet, genetics, muscle fiber types, and the kind of training performed.
Circulating hormones such as testosterone play a large role in the development of large muscles. Men have between 20 and 30 times more circulating testosterone than women, and it is for this reason, as well as the fact that men have more numerous and larger muscle fibers, that men can develop much bigger muscles than women. Keep in mind that genetics and individual differences play a role in the rate and degree to which muscles mass increases in either gender. Men and women who train similarly can increase their muscle strength, but because women have lower levels of testosterone and fewer and smaller muscle fibers than men do, they cannot increase muscle size the way men can.
Can supplements help me get stronger or leaner, develop more tone, or lose weight?
Millions of people rely on dietary supplements for everything from enhancing their sex lives to improving their athletic performances. There is essentially no systematic regulation of the dietary supplement industry, so there is no guarantee that any supplement will live up to its claims. More important, there is no guarantee that any supplement is safe. Some dietary supplements are probably safe and effective if consumed according to the manufacturers' instructions. An example is the traditional use of vitamin and mineral supplements. Although the recommended doses can improve a deficiency resulting from a poor diet, megadoses can have toxic effects. Because dietary supplements are not regulated by the U.S. Food and Drug Administration (FDA), there is no guarantee that what is stated on the label is actually in the supplement.
Will certain types of cardio help me burn more calories?
The type of exercise you select will determine the amount of energy you expend and, thus, how many total calories you burn. Many exercise modalities are marketed to women with the claim that they burn more calories, and the fitness consumer is left to wonder just what determines the number of calories burned during exercise. Just because you may sweat more in a particular workout (e.g., a cycle class or a hot yoga class) doesn't necessarily mean that you are burning more calories. Additionally, acute bouts of exercise do not burn a huge number of calories. It is the consistency of the exercise that results in weight loss.
Understanding what determines how many calories your body burns during exercise and why your body obeys certain rules that dictate the magnitude of caloric expenditure is important when selecting exercises. With this knowledge you can create realistic goals for yourself with respect to fat loss and increased lean mass. In addition, you will be in a better position to discern the truth regarding many of the advertising claims that suggest that a particular exercise modality is best for caloric expenditure and weight loss. The fact is, the more you exercise, the more fit you will become. You will burn more total calories walking briskly or running 5 miles (8 km) than you will just 1 mile (1.6 km). So instead of burning 100 calories for 1 mile, you burn about 500, and that's a lot more calories burned than if you had stayed on the couch. Bottom line: the harder you work, the more calories you expend, and you have to do this on a regular (ideally, daily) basis.