Moods, say the experts, are feelings that tend to become fixed, influencing one's outlook for hours, days or even weeks. That's great if your mood is a pleasant one, but a problem if you are sad, anxious, angry or simply lonely. Perhaps the best way to deal with such moods is to talk them out; sometimes, though, there is no one to listen. Modern pharmacology offers a lot of tranquilizers What many people don't realize, however, is that scientists have discovered the effectiveness of several non-drug methods to set you loose from an unwanted mood. These can be just as useful as drugs, and have the added benefit of being nonpoisonous. So next time you _ don't head for the drug-store but try the following methods. Of all the mood-altering self-help techniques, aerobic exercise seems to be the most efficient cure for a bad mood. "If you could keep up the exercise, you'd be in high spirits, " says Kathryn Lance, author of Running for Health and Beauty. Researchers have explained biochemical and various other changes that make exercise compare favourably to drugs as a mood raiser. Physical exertion such as housework, however, does little. The key is aerobic exercise--running, cycling, walking, swimming or other repetitive and sustained activities that increase the heart rate, increase blood circulation and improve the body's use of oxygen. Do some of the activities for at least 20 minutes a session three to five times a week. It can be inferred from the passage that  _
some drugs are more effective than physical exercises a person does not need aerobic exercise if he is in a good mood the best way to overcome a bad mood is to talk to oneself when in a bad mood, one may not work very efficiently