There are a few reasons why your massage therapist may choose to use deep tissue techniques that involve hitting or striking. First, it can help to release muscle tension. When muscles are tight, they can limit range of motion and cause pain. By breaking up the muscle tissue with hits or strikes, your therapist can more easily achieve the desired level of pressure without causing you discomfort. Additionally, this type of massage can also help improve circulation by increasing blood flow to the area being worked on.