Benefits of Moderate Level of Intensity

When you exercise, if you are not challenging your body consistently you will not reap the large majority of health benefits related to exercise. Exercising only 10 to 20 heart beats per minute above your resting heart rate will provide little to no benefit, other than serving as a safe warm-up and cool-down period during your routine. Moderate-level intensity exercises improve cardiovascular health, increase respiratory output, strengthen muscle, build endurance and improve mood, among many other benefits. Use a target heart-rate calculator to help you reach your moderate target heart-rate zone, which will aid you in burning calories and fat during your workout.

Considerations of Extremely High Intensity

It may be tempting to try to exercise at the highest intensity to try to reap maximum benefits. However, you should take caution when reaching 80 percent or greater of your target heart rate. If you have any cardiovascular or respiratory issues, this can be a dangerous level for you to work out for an extended period. Also, your body will begin to shift its metabolic efforts and will actually begin to burn muscle as your body is entering a crisis mode. And because this level is often very uncomfortable, it is more likely that you will abandon your workout regimen over time.

Research

A study from the Norwegian University of Science and Technology published in "PLoS One" in May of 2013 shows that just four minutes of high-intensity exercise three times per week showed the same health benefits as 16 minutes of high-intensity exercise three times per week. This and many other studies support the benefits of interval training. By controlling the level of intensity throughout your workout, you can reduce the overall strain and risk of injury associated with extended high level intensity exercise.

Interval Training

When exercising, start and finish with a low-level intensity to give your heart a chance to warm up and gently lower to a safe, post-workout level. Initiate moderate-level intensity five to 10 minutes after starting your routine. At least once during your workout, jump to a high intensity level for four minutes to really challenge your body and reap significantly increased metabolism during your entire day. Return to a moderate level and then finish with a low-level cool-down.