The only absolute truth in the area of exercise and weight loss is this: Becoming more physically active will burn calories, and as long as you don't absorb those calories back by eating more, you will lose weight. Getting active and getting your muscles to burn more calories is an essential part of a weight management program. It will improve your circulation and your nervous system more than any diet could. Regular exercise can fight all signs of aging, lower cholesterol ratings and reduce osteoporosis. But the question that fuels the multi-million dollar fitness industry is, "What exercise is best?"

This is a very contentious area. Mr. Weightless will only tell the simple truth, so below is the information that has been proven to be true, but the final judgment is yours.

Slow and Steady Wins the Race...

Slow and steady exercise that raises your heart rate a significant amount, but that still allows you to breathe without struggling for at least 20 minutes will encourage fat loss. This is called aerobic exercise. The term aerobic means "with air", meaning that your muscles are burning sugar and fat in the presence of oxygen. To be able to burn calories in the presence of oxygen, you have to be taking regular breaths, so the activity you're doing must be a moderate pace, at most. For many people who are overweight, this can mean simply a fast walk. For many athletes, this may be a quick jog. It doesn't matter where you are along the spectrum as long as your heart rate is raised and you can breathe normally or carry on a conversation.

Why 20 minutes? At first, your body will only burn blood-sugar because it is readily available. If you keep going long enough, your body realizes that blood- sugar won't be enough, so it starts burning fat as well. If you stop exercising before this happens, then your body will simply be tired and you will feel hungry because your blood-sugar will be low (see my article on Satiety, click here). Your body wants to retain the fat and avoid burning it. This is a survival mechanism... read my article on Adaptation that you can find on my website.

...Or Does Maximum Intensity?

There is another school of thought that has had similar success with just as much good theory behind it. Vigorous exercise for 10-15 minutes will burn just as many calories from your blood-sugar as a longer duration exercise, but it will also raise your metabolism for many hours afterwards. In other words, you won't burn fat during your workout, but you will slowly burn fat for a period of time after finishing. This method has been shown to have more dramatic effects on lowering body- fat than the low-intensity exercise described above. This is anaerobic exercise, meaning "without air". You'll be going fast enough that your breathing won't be enough to fuel the calorie burning. Carbohydrates (blood sugar) will burn without oxygen, which leads to the creation of lactic acid. This is what accumulates in your muscles, and makes them feel like they're burning.

However, there are serious drawbacks to this method, which make it difficult to recommend this strategy exclusively. Before embracing the high-intensity mindset, read below.

First, if a person is just starting a program, they risk serious injury if they try to exercise too vigorously. Knees, hips and ankle joints are very common injury sites, and muscle cramping can be very painful even if it is short-lived. Don't exercise at your peak intensity until you're used to exercising!

Secondly, high-energy activities tend to be high-impact on the body. Running fast, playing racketball, and jumping jacks wear down the connective tissues in the body, so even if a person is not directly injured, they are causing long-term damage. People who run road races often have chronic hip, knee and ankle pain. If you decide to pursue this type of high-energy program, I highly recommend a reclined stationary bike to reduce the strain on your joints.

The third problem is: How vigorous does a person need to exercise? If you go at your absolute peak, you may only last three minutes, maybe less, and that won't be effective. It is difficult to gauge how much you can push yourself to be exhausted exactly at 12 minutes.

Finally, though vigorous exercise technically takes less time, it requires changing into workout clothes, doing the exercise, then taking a shower and changing back again. That means scheduling more time for the preparation than for low-intensity activities, as well as having access to a place to change. On the other hand, going for a brisk walk you can do on a whim, maybe more than once a day, in your regular clothes.

The Best of Both Worlds: Two Alternatives

You can get good results using either method, but the best method is to combine the two. If you're in the gym using a stationary bike, your goal should be to do a warm-up of aerobic activity for about 20 minutes, followed by 10 minutes of anaerobic exercise. For many people, a 20 minute brisk walk followed by a 10 minute fast bicycling makes the most sense. For those who play high intensity sports like racketball, a light warm up on a stationary bike for 20 minutes before a match can kick-start the fat burning process. Everyone is different.

That may be too much for someone who is just starting out, though. The best recommendation is to start at a low intensity activity like walking, and gradually increasing the intensity week to week. A good way to do this is to walk down the street directly away from your home for 20 minutes, then turn around and walk back at a slightly quicker pace. This low-intensity 40 minute exercise every day should be fine for the first week. Don't aim to run right from the start, start slow, be patient, and improve consistently every day. After a week or two, turn the "walk away" portion into a quick power-walk and try to jog all the way back. Remember to use time, not distance, as your measuring-stick. Making your workouts shorter is NOT the goal, we always want our fat-burning exercise to last 30 minutes, and our warm-up aerobics to last 20 minutes, regardless of distance.

The best fat-burning work out is difficult to program into a stationary bike, and works best on the street. This is "interval training". This type of workout allows you to get the benefits of high-intensity exercise and make it last over 20 minutes to burn fat right away. The formula is simple: Walk for 2 minutes, then run for 1 minute. Then repeat. Use the walking portion to catch your breath and prepare for the next high-intensity interval. At first, your "high intensity" may simply be a jog, don't over do it. Over the weeks, increase the intensity of your high-intensity portion. When you get up to a run, do NOT try to increase the duration of the high- intensity portion. You'll benefit more by continuing to increase the pace to a sprint, if possible. Keep the duration of the entire work out to 30 minutes or more. As I mentioned above, with all street running, beware the impact on your joints.

Frequency

How regular should exercise be? Every day. Anyone can fit in one half hour into their schedule. You should look forward to the physical activity, so choose one that you like to do if walking isn't for you. Remember that you're training your body to lose weight. If you don't exercise every day, your body will think that when you do exercise, it's a minor exceptional change. Only by doing it every day will your body come to expect it, and will therefore prepare for it. Training your body to expect to burn calories is half the battle! If anything, take the stairs instead of the elevator.