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Every movement your body makes involves muscle contraction and the list of exercises available is endless. If your goal is to improve performance, understanding the types of muscular contractions, and which exercises utilize those contractions, will improve your muscular strength and performance.
Isotonic contraction is the force generated by a muscle while contracting, when the muscle lengthens and shortens during movement, with the force remaining constant. Therefore, when picking up a glass to take a drink your muscles would use the same force throughout the movement up and down, which is nearly impossible. During normal muscle contraction the force varies throughout the movement. A more accurate term is dynamic contraction, meaning the muscle tension varies as it moves the glass. Common exercises demonstrating this type of contraction are dumbbell curls, squats, lunges and walking. These forms of exercises help to isolate certain muscle groups, as in the case of dumbbell curls during which the primary muscle worked is the bicep.
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