Due to its mechanical properties, this form of training can be used for both healthy individuals and individuals who are in rehabilitation. Studies have shown that negative repetitions or "eccentric phase training" combines a high amount of force on the muscle with a lower energy cost than normal concentric training, which requires 4–5 times the amount of energy. This justifies why this type of training is more beneficial and less of a risk to subjects rehabilitating or with a limited exercise capacity.