" is achieved (Hay & Reid, 1988, p. 127). This type of control is especially important in punting where a relatively small angle of release of approximately 42 degrees is needed (Hay & Reid, 1988, p. 129). In movements of the lower extremities the range of motion of the leg is limited largely to the field of vision. Those motions that are outside that field are limited so that the trunk and the foot are never much beyond the range of vision (Weineck, 1990, p. 87). Control of most of the muscle movements discussed here involves a significant degree of visual coordination.
The anatomical and biomechanical analysis of the punting process is organized into three sections in which the movement of the joints and then the action of the muscles are discussed in relation to the principal movements: the flexion of the hip, the extension of the knee, and plantar flexion.
The hip joint is of the ball-and-socket type and is the articulation of the pelvis and the femur. The hip joint plays important roles in both stabilization and movement. The bony part of the joint includes the deep socket, or acetabulum, which is the articulation with the femur. Located on the pelvis, the joint faces in a slightly anterior direction and is held by a strip of ligament (labrum) which prevents anterior displacement, to which the joint is somewhat susceptible. The iliofemoral (Y) and pubofemoral ligaments add to stability and attach the femur to the pelvis . Posterior displacement is guarded against by the femoral ligament which attaches the joint to the top of the femur (Kreighbaum & Barthels, 1985, p. 218). The movement of the pelvis places the acetabulum in optimum positions for the femur's movements. The femur, which sits at a somewhat medialward angle to the pelvis, performs a large number of movements of which the two most important in the present context are flexion and extension. Flexion is one of the types of forward movement of the femur ...