"What is the principle that indicates the need for an individual to perform a specific type of exercise to improve fitness of a specific body part?" It is the principle of Specificity. If a person wants to improve a certain part of his body, he should therefore perform exercises that mainly targets that part.
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"What is the principle that indicates the need for an individual to perform a specific type of exercise to improve fitness of a specific body part?" It is the principle of Specificity. If a person wants to improve a certain part of his body, he should therefore perform exercises that mainly targets that part.