In another study, close to 3,000 retired men were enrolled in the Honolulu Heart Program to study the effects of walking on heart disease. The conclusion: The more they walked, the lower their risk of heart disease. Men who walked more than 2 miles per day were half as likely to get heart disease as men who walked less than 1 mile per day.
In both of these studies, subjects walked at a moderate pace of 3.0–4.0 miles per hour.
Spot-reducing exercises can trim my trouble spots.
There’s no such thing as spot-reducing. It would be nice if you could walk on the treadmill and say, “OK, today I’ll burn fat from my thighs.” But that’s not the way it works. Whether it tends to collect on your thighs or your tummy, fat on your body belongs to your entire body, and the only way to reduce it is through regular exercise and reducing your caloric intake. Here’s some information about storing and burning fat that should help you understand how aerobic exercise, weight lifting or other resistance exercise, and attention to your diet can help you lose weight.
Fat is stored in cells called adipocytes, which are located all over the body. When you eat more fat or calories than your body needs, the fat cells gobble up much of the excess and expand in size. The larger the cells, the higher your percentage of body fat. Where on the body your fat cells are located, where you tend to store fat first, and how efficient your adipocytes are at storing fat is genetically determined; you have no control over it. As a rule, men store fat in their abdomens, and women tend to store it in their buttocks, hips, and thighs. Similarly, people generally gain and lose weight in a consistent pattern. If you’ve lost and regained weight multiple times, you probably know where you tend to lose it from first (perhaps the face), and where it tends to stick the longest (often in the hips, thighs, and buttocks).
How does exercise help you get rid of fat? During exercise, hormones like adrenaline are released that signal the adipocytes to release fat into the bloodstream. That fat is then transported to the muscles to be burned for energy. When an adipocyte releases its stored fat, it shrinks. The cells themselves never disappear, but as long as the fat is used by the muscle and does not return to fatten up the adipocyte, you will lose overall body fat. Because you have no control over which adipocytes are stimulated to release fat, however, you cannot “spot-reduce” fat from a particular body part.
Aerobic exercise (such as biking, walking, or swimming) stimulates the release of more fat than does resistance exercise like weight lifting, leg lifts, or pushups. However, resistance exercise builds muscle, and muscle is the engine that burns fat and helps maintain metabolic rate. So if you’re trying to lose weight, an exercise program that includes aerobic activity as well as some type of calisthenics or weight lifting will probably help you the most.
Incidentally, although they don’t change your weight-loss pattern, exercises that work your abdomen, thighs, hips, and buttocks will indeed strengthen and tone the underlying muscles, so even if there is still that pesky layer of fat on top, your physique will be tighter and your clothes may even feel looser.
Exercise will make me hungry.
There is no compelling evidence that moderate exercise affects a person’s overall appetite; it neither makes you hungry nor suppresses your appetite. Some people report that they make better food choices if they exercise regularly, but this has not been studied carefully. The only time exercise is likely to make you hungry is if it’s been 3–4 hours since your last meal or snack, and you exercise on an empty stomach.
If I don’t sweat during exercise I’m not getting any benefit.
Sweating is important because it’s a way of cooling off muscles that heat up during exercise, but it is not necessarily an indicator of how hard you are working. Temperature, humidity, wind conditions, and even how you are dressed all affect how much you sweat on a given day. Moreover, not everyone sweats at the same rate.