INTENSITY VS WORK IN EXERCISE

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INTENSITY VS WORK IN EXERCISE
By Ken Hutchins

Often I must explain the answer to the following question:

“Isn’t it beneficial to expose the muscles to heavier weight by permitting ample rest between exercises? After all, I can perform each exercise with more weight if I rest several minutes between each exercise.”

As you continue this article, consider this to be the primary question.

For many years the “total tonnage” theory was popular. It epitomized the belief that the total work performed or weight (tonnage) lifted daily was a gauge for measuring exercise effectiveness and/or progression.

Both the primary questions and the total tonnage theory ignore the true cause and effect relationship between the exercise stimulus and the growth response mechanism.

Muscular growth occurs though a mechanism that we yet poorly understand. We do know, however, that the growth mechanism in healthy subjects is a response to working muscle in a high-intensity fashion.

High-intensity muscular work is therefore the stimulus, and muscular growth is the response. Realize that high-intensity work does not cause or produce growth. Your body produces the growth in response to the provided stimulus.

I believe that most of us—before t is pointed out for us-regard exercise and its beneficial effect—much like seeing artificial light for the first time. Pretend that we are in Edison’s lab back in 1990 and he demonstrates his invention to us. Processing a total ignorance of electricity and seeing no more on his work bench than a switch and some wires leading to a bulb, we easily assume that Edison’s manipulation of the switch causes the light. This being the only immediately available perspective on a supposition for the cause of light, we elect to make the light brighter—in Edison’s absence of course—by doing what we saw Edison do…manipulate the switch. We flip the switch repeatedly and progressively faster at first, then try pushing the switch harder, eventually striking it with our hand and then with a hammer. “What’s wrong?” we ask ourselves. “Why can’t we make more light?”

Our actions do have an effect on the bulb, however. Each time the switch is thrown on, a surge through the filaments of the bulb occurs which greatly shortens the life of the bulb. Also, each surge wastes electricity.

Our failure is due to the fact that we erroneously assume that the switch caused the light. We are ignorant of electricity’s role in the matter.

And similarly, if not perfectly the same, we do the same thing with exercise. We erroneously assume that the exercise causes the benefits, when it is merely the stimulus—albeit an essential stimulus.

No amount of easy activity affects the desired growth stimulus. For example, pretend that you wish to grow a callous on your hand. No amount of light stroking your palm with a feather will result in callous formation. But find something abrasive – a key perhaps – and scrape it across your finger pads so hard that it nearly breaks the skin. This stimulates callous formation that will occur if you wait several days and do not continue to abrade your palm to the point of blisters.

The mechanism of muscular growth works much the same way. You must work muscles hard to effect stimulation, then back off and permit the body to grow the muscles larger and stronger.

Intensity merely indicates how hard the muscular work or its degree of difficulty. The effectiveness of growth stimulation appears to be directly proportional to the intensity of muscular work during exercise. It is indirectly proportional to the amount of work.

Intensity may be denoted with the equation:

Intensity = inroad/time

This means that the shorter the time it takes to reach a given degree of inroad, the greater the intensity; or, the greater the inroad achieved in a given amount of time, the greater the intensity. Realize by reducing time, we’re reducing amount of work. The more work required to achieve a certain level of inroad, the less intense the exercise. These Jonesian definitions apply to the overall intensity of a workout as well as the intensity of a specific exercise.

Consider the primary question again and then study the following scenarios. The explanation is somewhat tedious. Carefully read it several time to insure accurate meaning.

Scenario #1
Suppose you perform five exercises to the point of muscular failure and rest 5 minutes between each exercise. Also assume that you inroad your strength 20% in each exercise.

Fresh strength is the maximum one-repetition force you can generate if the muscles involved are completely fresh – rested. Suppose that rather than perform a set of five repetitions, you perform only one repetition using as much weight as your strength will allow: Pretend that weight is 100 units (or 100%). Also suppose that you can perform exactly five repetitions with a 20% reduction (80 units or 80% of fresh strength). This is the weight we choose for the exercise set-denoted weight x repetitions.

Having performed 80 units for five repetitions, you cannot perform a sixth repetition, thus your strengt5h has fallen to 80-denoted ending strength. Your ending strength is actually somewhat less than 80, but for the sake of simplicity assume that inroad is 20%.

Further pretend that your fresh strength is 100 units is each of all five successive exercises. This, of course, assumes that you do each of these exercises as if dong them first-you are not fatigued the slightest by preceding exercises. Assume, however, that a rest of exactly five minutes is also adequate to completely replenish your strength. Thus, you are able to perform five-repetition sets with 80% of fresh strength in each successive exercise if provided a five-minute rest between the exercises.

Starting strength is the maximum one-repetition force you can generate in each exercise. In this scenario, by virtue of the five-minute rest between exercises, starting strength equals fresh strength and the 80% figure is the same in each exercise.

Depth of inroad/starting is the percentage of inroad from the starting strength in each exercise.

Depth of inroad/fresh is the percentage of inroad from the fresh strength in each exercise.

Scenario #2
This scenario is identical to Scenario #1 except that no rest is allowed between the exercises.

Fresh strength remains the same, of course. Starting strength after the first exercise, however, is somewhat less than fresh strength due to the inroading influence of the preceding exercise(s). This inroading influence becomes progressively greater as the workout proceeds to subsequent exercise.

And the weight X repetitions decreases as we take 80% of the ever-diminishing starting strength. Therefore, the resulting inroad from the original fresh strength level grows progressively greater.

Comparison
Comparing Scenario #1 and Scenario #2, note that the depths of inroad from the fresh strength levels are significantly greater when the rest interval is eliminated. This presumably indicates a more certain and thorough growth stimulation.

Also, note that the overall work performed is less when the muscles are worked harder-no rest between exercises. This is valuable since the amount of work is a major negative factor affecting our limited recovery system. If the recovery system is depleted too far by excessive work, growth is retarded, minimized, or prevented in spite of effective stimulation.

One more benefit: The high-intensity workout outlined in Scenario #2 exposes the body to less force—excepting the first exercise. Since excessive force is primarily the result of acceleration—sudden, jerky movement—this is a minor benefit, but a benefit nevertheless.

Summary
Deep muscular stimulation is enhanced when exercises are performed to failure with a minimum of rest between them. Also, less total work is performed from which the body must recover. Of course, these observations ideally ignore the limitations of the ventilation and vascular subsystems to permit such continual work. These subsystems are often the limiting factors in the pure application of these principles.