Training effect

Training effect refers to specific changes in muscular, cardiovascular, and neurohumoral systems that lead to improvement in functional capacity and strength due to regular endurance or resistance training. It has also been defined as a reaction to the adaptive responses of the body created by a training program or as "an elevation of metabolism produced by exercise".

Kenneth H. Cooper for the United States Air Force discovered this effect in the late 1960s and coined the term.

The measured effects were that muscles of respiration were strengthened, the heart was strengthened, blood pressure was sometimes lowered and the total amount of blood and number of red blood cells increased, making the blood a more efficient carrier of oxygen. VO₂ Max was increased.

The exercise necessary can be accomplished by any aerobic exercise in a wide variety of schedules - Cooper found it best to award "points" for each amount of exercise and require 30 points a week to maintain the Training Effect.

Cooper instead recommended a "12-minute test" (the Cooper test) followed by adherence to the appropriate starting-up schedule in his book. As always, he recommends that a physical exam should precede any exercise program. (A newly recognized effect is that of Exercise hypertension, for which there is a medical test.)

The physiological effects of training have received much further study since Cooper's original work. It is now generally considered that effects of exercise on general metabolic rate (post-exercise) are comparatively small and the greatest effect occurs for only a few hours. Though endurance training does increase the VO₂ max of many people, there is considerable variation in the degree to which it increases VO₂ max between individuals.

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