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Coast Guard Athleticism Program

Cardiovascular Conditioning (Energy System Development)

When people usually think of cardiovascular fitness the first thing that comes to mind is long, slow runs, and the assumption is the longer you can go the better shape you are in. Although this is a valid measure of specific fitness, the approach isn't necessarily the most effective training approach to elicit great improvements in cardiovascular fitness. In fact, if this is all you do during training, you are more likely to hit a plateau and suffer from aches and pains associated with large volumes of repetitive stress under fatigue.

Interval training is an alternate approach to long, slow duration training. This involves training that alternates between short, intense bouts of exercise and periods of true recovery. This will take you from an effort level that is easy, up to a hard effort, and then back down to an easy effort. To do a "true interval," you must allow your heart rate to truly recover before picking the intensity back up. The following are some of the key benefits of interval training.

In order to bring about positive physical changes to your cardiovascular system, the body must be presented with a workload that challenges its current fitness state. By overloading the heart and lungs, you are increasing your endurance and cardiovascular fitness level, which is the same principle as weight training (overloading a muscle will result in increasing the muscle's strength). The heart is a muscle, so it must be overloaded to improve its strength. At the same time, the rest of the respiratory system is improving, including the lungs and blood circulation, for better endurance. This workload will cause fatigue, and with proper recovery, will eventually yield cardiovascular improvements. It is important to note that the overload happens during training, while adaptation occurs during recovery - thus, making recovery a vital part of your programming.

Increased Caloric Burn:
Another advantage of interval training is that you can actually burn more total calories in the same amount of training time.

By designing intervals into your conditioning session, you are provided with variety across each workout. The working intervals are kept to about 5-minute work sets, balanced with the appropriate amount of recovery to help facilitate this motivation. You will be much more inclined to push yourself during the training, if you know you will get a chance to recover shortly.

Another benefit of interval training is that it increases your metabolism, both during your training session and after. It is not just about what your body is doing during the workout; it is important to understand what your body is doing the rest of the day. Studies have shown that interval training raises your metabolism after a workout, and keeps it up longer than any "steady state" workout. Steady state exercise refers to any exercise that stays at the same workload for a long period of time.

Increase Anaerobic Threshold:
Interval training allows us to train at a higher intensity for a longer period of time throughout the duration of our training session, due to the intermittent recovery throughout. As our bodies become more efficient, we are able to train at a higher intensity without crossing over into our anaerobic energy system. This results in more calories being burned, an increased threshold to fatigue and quicker recovery between bursts of activity.

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Last Modified 1/12/2016