I believe it is the Biceps Femoris muscle.
There is no muscle named triceps femoris. The triceps brachii is a muscle in the arm with three heads, while the femoris muscles are in the thigh. The hamstring group includes the biceps femoris, semitendinosus, and semimembranosus.
The hamstring (back / dorsal side of the thigh)
The biceps femoris runs down the outside of the leg and inserts on the head of the fibula, the semitendinosus runs down the inside of the leg and inserts on the front of the tibia and the semimembranosus runs down the inside of the leg underneath the semitendinosus and inserts on the front of the tibia as well.
The muscle in the back of the thigh is the hamstring, or the biceps femoris to be technical.
The primary antagonist to the rectus femoris is the biceps femoris, a muscle of the hamstring group. When the rectus femoris contracts to flex the hip and extend the knee, the biceps femoris acts to flex the knee and extend the hip, helping to create balanced movement.
The hamstring muscle group (biceps femoris, semitendonosis, semimembranosis) are the antagonists to the quadricep group.
Hamstring to the rear thigh muscles (semitendonosis, semimembranosus, and biceps femoris). Therefore, it is a part of the muscle system.
hamstring group, made up of semitendinosus, semimembranosus, and the biceps femoris.
biceps femoris
biceps femoris, semitendinosus and semimembranosus
semimembranosus and semitendinosus musclesHamstring (ham = fat/muscle behind knee + string = tendons) is a medical term referring to a group of tendons behind the knee.The three muscles involved:SemitendinosusSemimembranosusBiceps femoris