What training approach requires special machines equipped with mechanical devices that provide differing amounts of resistance, with the intent of overloading the muscle group maximally through the entire range of motion?

The variable resistance training is a training approach which requires special machines equipped with mechanical devices that provide differing amounts of resistance. These devices have the intent of overloading the muscle group maximally through the entire range of motion. An example of which is when a lifter adds elastic bands to a lift. 

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