Strength Beginners Anatomy of the Hamstring Muscles By Paul Rogers Paul Rogers is a personal trainer with experience in a wide range of sports, including track, triathlon, marathon, hockey, tennis, and baseball. Learn about our editorial process Paul Rogers Reviewed by Reviewed by Michael Lau, PT, DPT on August 27, 2019 facebook twitter linkedin instagram Michael Lau, PT, DPT, CSCS, is a licensed physical therapist, strength and conditioning coach, and co-founder of The Prehab Guys. Learn about our Review Board Michael Lau, PT, DPT Updated on September 13, 2019 Print MedicalRF.com/MedicalRF.com/Getty Images Table of Contents View All Function Exercises Stretches Injuries The hamstrings are a group of muscles and their tendons at the rear of the upper leg. They include the biceps femoris, semitendinosus, and semimembranosus. The hamstrings flex the knee joint and extend the thigh to the back side of the body. They are used in walking, running, and many other physical activities. The hamstring muscles have their origin, where their tendons attach to bone, at the ischial tuberosity of the hip (often called the sitting bones) at one end and the linea aspera of the femur at the other. The hamstring tendons flank the space behind the knee. The most medial muscle, the semimembranosus, inserts on the medial condyle of the tibia bone. The semitendinosus inserts on the superior part of the medial tibia. The most lateral hamstring, the biceps femoris, inserts on the lateral side of the fibula and also attaches to the superior part of the lateral tibia. They are innervated by the sciatic nerve. What Do the Hamstrings Do? You use the hamstrings for walking, running, and jumping. They flex the knee and extend the hip at the beginning of each step. In walking and running, they are antagonists to the quadriceps muscles in the action of deceleration of knee extension. Because the hamstrings have their origin at the sitting bones, they are stretched while sitting, and long periods of sitting may affect their function. Hamstring Exercises Walking, running, and climbing and descending stairs builds the functional fitness of the hamstrings. This can be important cross-training for people whose primary exercise is bicycling, which targets the quadriceps. Overdevelopment of the quadriceps needs to be balanced with exercising the hamstrings. Isolation and compound exercises for the hamstrings may be used for rehabilitation or bodybuilding. Exercises that involve knee flexion and hip extension are used to build the hamstring muscles. Hamstring Stretches Hamstring flexibility is important for runners and may help prevent injury and delayed onset muscle soreness after exercise. Tight hamstrings may also be felt as limited motion when straightening the knee or a cramp at the back of the knee. Hamstring stretches are a common part of a stretching and flexibility routine. Sore After a Workout? What You Need to Know About DOMS Hamstring Injuries The hamstrings take a beating during sports such as soccer, football, basketball and tennis, where running is combined with rapid starts and stops. Hamstring sprains and tears are common. Worse hamstring injuries are evident when there is significant bruising behind the thigh. Repetitive stress injuries from running or walking might also be the cause of hamstring pain. Was this page helpful? Thanks for your feedback! Get exercise tips to make your workouts less work and more fun. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Ramos GA, Arliani GG, Astur DC, Pochini AC, Ejnisman B, Cohen M. Rehabilitation of hamstring muscle injuries: a literature review. Rev Bras Ortop. 2017;52(1):11-16. doi:10.1016/j.rboe.2016.12.002 Al-Johani AH, Kachanathu SJ, Hafez AR, et al. Comparative study of hamstring and quadriceps strengthening treatments in the management of knee osteoarthritis. J Phys Ther Sci. 2014;26(6):817-20. doi:10.1589/jpts.26.817 Tsaklis P, Malliaropoulos N, Mendiguchia J, et al. Muscle and intensity based hamstring exercise classification in elite female track and field athletes: Implications for exercise selection during rehabilitation. Open Access J Sports Med. 2015;6:209-17. doi:10.2147/OAJSM.S79189 Davis Hammonds AL, Laudner KG, McCaw S, McLoda TA. Acute lower extremity running kinematics after a hamstring stretch. J Athl Train. 2012;47(1):5-14. doi:10.4085/1062-6050-47.1.5 Ernlund L, Vieira LA. Hamstring injuries: update article. Rev Bras Ortop. 2017;52(4):373-382. doi:10.1016/j.rboe.2017.05.005