Which of the following is part of the posterior chain?

• A. Hamstrings (biceps femoris, semitendinosus, semimembranosus)
• B. Biceps brachii
• C. Rectus abdominis
• D. Front deltoid

Answer: (A)

The posterior chain comprises the muscles on the back side of the body that drive hip extension and support the spine. The hamstrings, located at the back of the thigh, cross both the hip and knee joints and power hip extension and knee flexion, making them a primary posterior chain muscle. This is especially evident in movements like deadlifts, kettlebell swings, and hip hinges where the hips drive the movement and the hamstrings help stabilize the knee and hip.

The other options sit on the front or side of the body: the biceps brachii is on the front of the upper arm and helps elbow flexion; the rectus abdominis runs along the front of the abdomen and flexes the trunk; the front deltoid is the anterior portion of the shoulder. None of these are part of the posterior chain.