Low intensity aerobic exercises burn more fat calories than carbohydrate calories; at moderate to high intensity levels, a greater percentage of carbohydrate calories are used up by the body. This is why moderate to high intensity aerobic is better than low intensity aerobic – more calories are burned and used by the body in performing the physical activity, especially if you can keep it up for long periods (30 minutes or more continuously).

The logic is fairly simple: the longer you perform medium to high intensity aerobic work outs, the more calories you burn; the more calories you burn, the more fat you lose. In performing longer workouts, the body favors the use of glycogen early in the workout, as your glycogen supply becomes depleted, the body turns to stored body fat as the primary fuel source.

Moderate to high intensity aerobics for more than 30 minutes result in health benefits such as decreased blood pressure, decreased blood cholesterol and lowered resting heart rate.

The minimum recommended duration of moderate to high intensity aerobic workout is 30 minutes and the maximum is 60 minutes. Most body types respond to a 30 minute continuous aerobic exercise to burn a significant amount of body fat; 30 to 45 minutes continuously per session is the recommended duration for optimum fat loss and 60 minutes should be the maximum. Going beyond 60 minutes per aerobic session increases the likelihood of injury, over-training and adaptation.

Frequency of Aerobic Exercises

At a minimum, you should do 3 days per week of 20 to 30 minutes aerobic workout as part of your routine, for health reasons and fat loss. The number of days per week you do aerobic workouts is largely dependent on your goals. If fat loss is your goal, then you can increase the frequency to 4 or 5 or even make it a daily regimen to maximize results.

If you are just starting out with the program, 3 days a week of aerobic training should be the baseline. Since your body is not used to strenuous physical activities, initial results are very impressive. However, the baseline 3 day weekly aerobics workout is used only as a starting point or as maintenance level workout. Results are immediate because any increase in physical activity from zero activity always produces results; however, these results will soon taper off (another progress gap) as the body adapts itself to the new nutrition and physical regimen. When this happens, it is necessary to gradually increase the frequency of physical activity.

For best results of the program, recommended frequencies of aerobic exercises are as follows:

-Maintenance, Health and Physical Conditioning: 3-4 Days/Weekly
-Maximum Fat Loss: 5-7 Days/Weekly