These are also often referred to as Passive Care Techniques as you are passively having care applied to you.
Light therapy uses a specific wave length of light that activates the energy factory within the cell. By providing more energy in the form of light, the mitochondria of the cells can increase their rate of energy production. This increase in usable energy allows damaged tissue to heal itself more quickly.
Therapeutic Ultrasound, not to be confused with diagnostic ultrasound that allows us to see images, is a method of stimulating tissue beneath the skin's surface using sound waves. It is a very high frequency massage that can penetrate up to 5" below the surface of your skin. The sound waves are of a very high frequency, typically between 800,000Hz and 2,000,000Hz. The sound can not be heard by humans or animals. This very high frequency sound affects very small molecules in the cells in your body and actually causes them to move. It is this movement that creates the massage or heating of the injured tissues
The heating and massaging effects of Therapeutic Ultrasound increase blood flow in the treated area which speeds the healing process, reduce swelling and edema which are the main sources of pain and gently massages the muscles, tendons and/or ligaments in the treated area. This enhances the recovery rate of damaged tissue without adding strain, and softens any scar tissue that can develop in an injured area.
Electrical Muscle Stimulation
Electrical stimulation uses electrical impulses that are delivered through pads placed directly on the skin. This electricity serves to decrease pain, swelling and muscular tightness while increasing bloodflow and increasing the ability of the injured tissue to heal. If applied in a manner to activate muscle, electrical stimulation can strengthen the muscle. This may also be applied in combination with ultrasound.
TENS - Transcutaneous Electrical Nerve Stimulation
TENS units are often though of as a portable version of the electrical stimulation described above. While partially true, the main goal of TENS is to decrease pain through the use of nerve distracting electricity. The large advantage of TENS is that it is completely portable and may be used when you need it for pain reduction.