In order for your body to utilize stored fat, you must do aerobic exercise or aerobic activity. This simply means you must do some exercise or activity that burns a lot of oxygen, since a lot of oxygen is needed to metabolize/burn fat. Aerobic exercise is any exercise sustainable over a long period.
Walking is one of the best ways to exercise aerobically since you are using large muscle groups, causing blood to circulate throughout the whole body, and it’s an exercise that can be sustained for a long time.
Weight lifting with heavy weights, on the other hand, cannot be sustained for a long time and doesn’t require oxygen to get fuel to the muscles. The energy for weight lifting is provided by fuel stored in the muscle itself, which is easily accessed, but there is only a limited supply so you can’t sustain the activity for very long. Weight lifting is a matter of strengthening (adding more muscle fibers) and neuromuscular (nerve to muscle) conditioning rather than cardiovascular (heart and blood vessel) conditioning.
According to Prevention Magazine, if you walk a mile, you’ll burn 100 calories, no matter how fast you go. A pound of fat is 3500 calories, so if you walk two miles a day, it will take you about 18 days to lose one pound. However, in typical weight loss, for each pound lost, only 55% is fat loss and the other 45% is muscle loss. It could actually take 33 days to lose a pound of fat by walking.
It is very important to do strengthening exercise and aerobic exercise at the same time in order to minimize the muscle loss. Also, if you are eating a diet high in sugar, your body will be creating more fat, so you may be losing more muscle mass than fat when doing a moderate aerobic exercise program.
Another little tidbit of information for you – one pound of fat requires 5 miles of blood vessels to supply it. It’s no wonder blood pressure goes up with fat gain as the poor heart has to pump more and more with increased resistance.
Aerobic exercise also reduces the risk for insulin resistance (the condition where the cells become less sensitive to insulin) and makes it harder to transport blood sugar into the cells.
All weight loss is not the same. Some weight loss is from water loss, other weight loss is from losing muscle mass and then there is weight loss from losing fat. Losing only water may interfere with proper cell and organ function, so this is not a good long-term solution to healthy weight loss.
Losing muscle mass makes you weaker and less able to do activity. A study has shown that one popular protein shake designed for weight loss did in fact result in losing more weight overall than another protein shake.
However, when body composition analysis was done, the weight loss showed more muscle mass lost than fat. It was just the opposite with the other protein shake, even though the overall weight loss was less.