POWER TESTING CONCEPTS
Kraemer, W. J., & Newton, R. U. (1994). Training for improved vertical jump. Sports Science Exchange, 7(6), 1-12.
Explosive power is a requirement for success in many athletic skills. This is not to be confused with the common concept of strength. Strength may be talked of frequently and trained commonly but the way it is practiced is not good for many sports. A typical explosive strength action is the vertical jump.
"Dynamic strength is defined as the maximal ability of a muscle to exert force or torque at a specified velocity . . . and is often assessed by using a one-repetition-maximum (1 RM) test, in which strength is defined as the maximal weight an athlete can lift one time through the entire range of motion. However, tests of 1 RM strength are of limited practical value because this specific type of strength is employed in only a few athletic endeavors, such as power lifting. Most sports require the explosive application of force to accelerate the body or limb, whereas 1 RM strength tests do not require rapid acceleration to produce the necessary force. In fact, 1 RM type of strength is maximized during slow muscle actions and minimized as the velocity of movement increases [the faster a movement the less strength that can be used]. Conversely, vertical jump performance requires great power, that is, the ability to exert force rapidly through a vertical distance." (p. 2)
Actions such as throwing a discus, long, high, or triple jumping, starting in a sprint race, and pulling an oar all have speed of movement while overcoming considerable resistance as the primary performance criterion.
Kraemer and Newton list the following features as characteristics of explosive power which need to be measured to analyze strengths and weaknesses in movements and also to design appropriate training programs. The item and test possibilities are those suggested for vertical jump training.
This is the capacity that should be trained for maximizing performance where speed and power are demanded. The possibilities for improvement reside in the characteristics cited above however, actual tests have to be adapted to the activity in question.
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