Abstract
It is essential for physical therapists, whose main role is to help people to improve their activities of daily living, to have an ability to solve muscle weakness and muscle tonus abnormality. This article describes the mechanisms of muscle power increase from the perspective of absolute muscle power and cross-sectional area of a muscle. In addition, two examples of the most commonly used exercises in clinical practice are used to show how the authors developed a way to enhance the activities of weak muscles by showing EMG wave patterns. We hope this article will help physical therapists to review their basic knowledge of muscle strengthening exercises.
