It’s something most of us feel guilty about not doing enough of. Yet working up a sweat is a guaranteed route to relaxation. Aerobic exercise – anything that speeds up your heartbeat, but not necessarily an aerobics class – increases the brain’s output of endorphins which gives a natural high.

Lively exercise improves whatever mood you’re in – if you’re depressed it will cheer you up, and if you’re fine it’ll leave you feeling dynamic. It also works off harmful stress hormones. And the fitter you get through regular exercise , the better your body can cope with stress. It may at first seem like hard work, but you’ll soon find that it can be food fun at the same time as being good for you!

Physically, exercise improves your cardiovascular functions by strengthening and enlarging the heart, causing greater elasticity of the blood vessels, increasing oxygen throughout your body, and lowering your blood levels of fats such as cholesterol and triglycerides. All of this, of course, means less chance of developing heart conditions, strokes, or high blood pressure.

Mentally, exercise provides an outlet for negative emotions such as frustration, anger, and irritability, thereby promoting a more positive mood and outlook. Exercise improves mood by producing positive biochemical changes in the body and brain. Regular exercise reduces the amount of adrenal hormones your body releases in response to stress. Also, with exercise, your body releases greater amounts of endorphins, the powerful, pain-relieving, mood-elevating chemicals in the brain. Depressed people often lack these neurochemicals. Endorphins are natural pain killers and also help lift your mood. The runner's high is a result of the increased endorphins in the body. Exercise, therefore, will keep your body functioning properly and will keep you feeling both relaxed, refreshed and promote deep, restful sleep

Exercise seems to be a popular 'fix' for stress, this is something that must be approached with caution. For people who have a sedentary job or lifestyle it could work wonders. For the person who is already overworked and physically drained it simply does not make any sense whatsoever to add any additional workload.

Begin an exercise that you enjoy, Preferably, do something that brings you into contact with other people. The value of such exercise, three times a week for 20 minutes to two hours, can not be over emphasised.

Problems always seem less important when you are walking, swimming, running, cycling, or are involved in any physical pursuit; apart from the mental benefits, physical exercise uses up excess adrenaline.

Exercise has another beneficial effect. Most people, when exercising, do not worry. They are actually resting the nerve cells in the brain that worry, giving those cells time to renew themselves, so they can function normally the next time they are needed. There are other ways of "resting your mind". Dancing, listening to music, reading, working on a craft, playing a musical instrument, meditation, reiki, self relaxation, and biofeedback also relieve stress. Any activity which concentrates your attention on a subject other than life's problems will help rest your mind. This allows the brain to renew itself.

Aerobic vs. Anaerobic Exercise
There are two types of exercise that perform different functions. Aerobic exercise is sustained activity involving the major muscle groups, such as swimming, running, or brisk walking. Your heart and respiratory rate increase, and more oxygen is circulated through the body. This kind of exercise strengthens your cardiovascular system and increases your overall strength and stamina. The goal of aerobic exercise is for your pulse to reach a training rate that is appropriate for your age. You must stay at the rate for twenty minutes, and exercise three times a week, in order to reap the benefits of aerobic exercise.

You've probably heard of "low-impact," or anaerobic, exercise. This means that you are not exercising vigorously or long enough to reach and maintain your training heart rate. It does not mean, however, that low-impact exercise is useless. It improves your muscle strength and flexibility and can still be a good outlet for negative feelings that you might have bottled up.

There are three kinds of anaerobic exercise. 

1. Isotonics require that your muscles contract against a resistant object with movement, such as in weight lifting. 

2. Isometrics requires that your muscles contract against resistance without movement. Isometric exercises increase strength without building bulk. 

3. Calisthenics are stretching exercises, such as sit-ups, toe-touches, and knee-bends, help increase flexibility and joint mobility. 

The kinds of exercises you choose to do depend on your physical ability as well as your preferences. The most important rule is to choose activities that you enjoy and that are accessible and feasible for you to do regularly. You also should consider whether you want to make your exercise routine personal time in which you can be alone with your thoughts or a more social activity. Some people find that exercising with others provides them with support and encouragement and it can even be fun!

Before you begin an exercise programme, you should have a physical examination. If you are over the age of forty, your doctor will probably want to do a stress electrocardiogram to determine how much activity your heart can handle. If you have not exercised regularly for some time, begin slowly with low-impact exercise and gradually increase your activity. If you experience any adverse side effects, such as dizziness, cramps, or chest pain, stop exercising and consult your doctor.

A Good Exercise Programme
There are a number of aspects to a good exercise programme.

Regular physical work. Regular physical work.

This should be endurance-type work – ie., effort that is sustainable for at least 20 to 60 minutes.

This work should be primarily aerobic with intermittent bouts of anaerobic work. 

Exercise should be done three times each week. 
The human body craves consistency and can make adjustments to long-term demands placed upon it. If you exercise three times per week, it will have a conditioning effect on your heart, but the heart is not the only thing that needs to perform efficiently during exercise. The other organs and muscle tissues will respond much differently to five days in a row. For five days in a row, the body continues to receive the message that it needs to perform efficiently in order to keep up. It adjusts to meet the demand and the result is efficient operation of the whole system, all the time, even on the two days you don't exercise.

Most people gain weight due to stress and not because of increased food intake or reduction in activity levels. Combining regular, vigorous exercise along with eliminating stress can bring about a reversal: significant weight reduction. 

Five days of regular, vigorous exercise does stimulate efficiency throughout the body. Too much vigorous exercise can cause the body to go into the survival mode and cause damage to the regular efficient system. This is why it is vital that exercise is begun gradually and increased gradually.