Answer :
Final answer:
High frequency treatments like ultrasound diathermy help in relieving pain and improving muscle flexibility by providing deep heat to tissues, using frequencies between 0.8 to 1 MHz.
Explanation:
A beneficial effect of a direct high frequency treatment such as ultrasound diathermy is its ability to relieve pain and improve flexibility in injured or overworked muscles. This treatment uses high-intensity ultrasound, whereby most of the energy is converted into thermal energy, to provide deep-heating to tissues.
Applying frequencies between 0.8 to 1 MHz and intensities ranging from 10³ to 10⁴ W/m² aids in the healing process by reducing pain, and is commonly used in athletics and physical therapy. It is important for therapists to use skill in order to avoid potential tissue damage such as 'bone burns' caused by overheating and cavitation, which could be exacerbated by the ultrasound reflecting off joint and bone tissue.
