Understanding how muscles work is important for performers in different sports. (a) Name the muscle that is used to flex the hip when a footballer kicks a b...

Muscles and their roles in sport

(a) The muscle used to flex the hip when a footballer kicks a ball is the hip flexor (iliopsoas or rectus femoris). This muscle contracts to swing the thigh forward, which is the driving action of the kicking leg. [1]

(b) The large muscle at the back of the thigh is the hamstrings. [1] During running, the hamstrings flex the knee, pulling the lower leg back during the recovery phase of the stride. This action brings the heel up toward the buttock after the foot has left the ground, preparing the leg for the next forward swing. [1]

(c) Roles of trapezius and latissimus dorsi during rowing

The trapezius is a large diamond-shaped muscle in the upper back. During the drive phase of a rowing stroke, the trapezius contracts to pull the shoulders back and retract the scapulae (shoulder blades). [1] This stabilises the shoulder girdle and creates a strong platform from which the arms can pull, allowing effective force transfer from the legs through the trunk to the oar. [1]

The latissimus dorsi is a broad muscle spanning the mid and lower back. During rowing, it contracts to extend and adduct the shoulder joint. [1] This pulls the upper arm backward and downward, which is the primary arm action that draws the oar through the water with force. [1]

(d) Gluteal muscles in gymnastics

The gluteal muscles (gluteals) are located in the buttock and their primary action is to extend the hip joint, straightening the leg backward. [1] A gymnast needs strong gluteals because many skills require powerful hip extension to generate height, rotation, and controlled body positions. [1] For example, performing a vault requires an explosive take-off from the springboard where the gluteals drive the hips upward and forward. Strong gluteals contribute to the height achieved and the ability to complete rotations in the air. [1]