In hamstring strains that are less severe, tearing is microscopic. The muscle fibers are essentially stretched too far. While some bleeding occurs within the muscle.
In the case of very severe hamstring strains, the hamstring muscle can rupture completely requiring surgery to repair the torn muscle ends. What severity of stain do you have?
Grade I Strain: Mild discomfort, often no disability. Usually does not limit activity.
Grade II Strain: Moderate discomfort, can limit ability to perform activities such as running and jumping. May have moderate swelling and bruising associated.
Grade III Strain: Severe injury that can cause pain with walking. Often people complain of muscle spasm, swelling, and significant bruising.
KT taping is appropriate for both Grade I and II hamstring strains. However, you should seek professional medical attention for grade III strains and use KT Tape as part of a larger treatment plan.