Moist heat & stretching are beneficial for chronic hamstring strain to prevent muscular hypertonicity, myofascial trigger points, and myofascial adhesions.
The goal of manual therapy for a chronic hamstring strain is to decrease hamstring hypertonicity and help promote healthy scar formation.
The most common symptom of hamstring strain is pain at the site of the strain. When acute the pain is sharp; when chronic, the pain is usually dull.
A hamstring strain, also known in lay terms as a hamstring pull, is by definition a tearing of the hamstring musculature.