Which muscle group flexes and rotates the spine to bend forwards?

Which muscle group flexes and rotates the spine to bend forwards?

• A. Quadriceps
• B. Abdominals
• C. Hamstrings
• D. Gastrocnemius

Answer: (B)

Abdominal muscles are responsible for bending the trunk forward. The rectus abdominis pulls the ribs toward the pelvis to flex the spine, while the obliques help rotate the trunk, allowing twisting as you bend. The other muscles act on joints other than the spine: the quadriceps straighten the knee, the hamstrings bend the knee and assist hip movement, and the gastrocnemius points the toes and helps knee function. So the group that flexes the spine and can rotate the trunk to produce a forward bend is the abdominals.

Abdominal muscles are responsible for bending the trunk forward. The rectus abdominis pulls the ribs toward the pelvis to flex the spine, while the obliques help rotate the trunk, allowing twisting as you bend. The other muscles act on joints other than the spine: the quadriceps straighten the knee, the hamstrings bend the knee and assist hip movement, and the gastrocnemius points the toes and helps knee function. So the group that flexes the spine and can rotate the trunk to produce a forward bend is the abdominals.