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Perhaps like most Americans you have some extra pounds to
{{U}} (47) {{/U}}. You may even have tried a fad diet or two, but found
yourself right back where you started. The key to weight loss is regular
{{U}} (48) {{/U}} activity. And surprisingly, you don’t have to give up
eating or make the gym your second home to see long-term, {{U}} (49)
{{/U}} effects.
Your body needs a certain amount of energy
to maintain basic {{U}} (50) {{/U}} such as breathing, blood circulation
and digestion. The energy required to keep your organs functioning is referred
to as the resting or basal metabolic rate.
Any time you are
active, {{U}} (51) {{/U}} energy is required. It is obtained from
glycogen and fat stored in the blood, liver, and muscles. The key to losing
weight is to draw on the fat rather than on the carbohydrate reserves.
Which of the two energy sources you use depends on the intensity and
{{U}} (52) {{/U}} of your activity. The