Body Science: The High Intensity Effect- Calories, Weakness, and Healthy Bodies Part 2

Part I we discussed Muscle Activation. In this post we will be discussing how speed affects Weight Movement. This is the area that contributes the most towards a possible injury.

Weight Movement – In the biomechanics of force, speed is squared in the equation. This is good for developing force and moving weight, bad for risk of injury if an individual does not have correct form. Speeding up a movement allows you to use more weight and work muscles harder, it can also greatly increase your risk of injury if not done correctly.

The trend of higher intensity exercise programs has highlighted the need to increase speed of movement and how it improves the body (burn more calories in the same time) when compared to slower workouts utilizing exercise machines. The ability to use your fast twitch muscle fibers can be retained with correct training and therefore, reduce your risk of falls, etc. The use of speed drills, agility drills, plyometrics (box jumps) can be a great addition to an exercise program, if you follow protocols. This is were we fall into the more is better principle of 40 box jumps (4 sets of 10 for a beginner) is protocol, so 100 will get us the results we want faster (if you don’t get hurt).

A good coach or trainer knows that correctly manipulating all of the variables (sets, repetitions, rest periods, box height, type of exercise, order of exercise, weight, etc) can keep you consistently progressing while reducing the risk of injury.

Lesson- Moving too light of a weight or too slow means you only use a limited amount of muscle (fiber). Muscle equals metabolism, the more muscle you have/more muscles you use, the more calories you burn!

High intensity exercise is a great part of a complete exercise program. Due to the nature of many exercises used, they do not work all major muscle groups equally. Over time this can cause significant muscle imbalances and lead to injuries. Augment your high intensity work with exercises to address any muscle or mobility imbalances, past injuries, and sport or goals specific training.

This post is to answer a physiology question that was submitted on our website. If you have a specific training or physiology question, please contact us on our website listed below.
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