Starting Strength

the torso parallel to the floor. It is important to lead up with the chest, making it draw the back into extension – a full arch at the top of the movement. It works the spinal erectors, the glutes, and the upper hamstring function.

    Figure 7-50. (A) Back extensions and (B) Roman chair sit-ups.

    The glute/ham bench is a modified Roman chair that allows the back extension to be carried on up into a bodyweight “leg curl” in an exercise called a glute/ham raise . Glute/ham benches are becoming more popular as more people figure out the utility of the glute/ham raise. In the finish position of the glute/ham raise, your torso is vertical. This exercise thus includes all the elements of the back extension but with lots and lots more hamstring involvement. The modification that allows this added movement is a plate welded onto the frame right behind the foot roller ( Figure 7-51 ). This plate gives the feet a place to push against, allowing a knee flexion to occur which carries the torso and thighs on up to the vertical position. The hamstrings can do this with the plate against the feet because they have the help of the gastrocnemius, which cannot contribute to knee flexion unless its proximal function is facilitated by having its distal function blocked against the plate.

    Figure 7-51. A glute/ham bench, a modified adjustable Roman chair with toe plates for the full-range-of-motion exercise.

    Muscles that cross two joints can affect movement around either joint. The proximal function is that which is performed by the joint closest to the center of the body, and the distal function is performed on the other end of the bone, the one farthest away. Most of the joints in the body are moved by muscles that also attach across another joint. The hamstrings are perhaps the most classic example because they both extend the hips and flex the knees – the glute/ham raise causes them to do both. The gastroc is another example of this type of muscle; it attaches to the calcaneus, or heel bone, by the Achilles tendon, and attaches to the lateral and medial epicondyles of the femur, behind the knee, as it splits into right and left heads. The gastroc both extends the ankle (an action referred to as “plantar flexion” in this particular instance) and flexes the knee. The other major calf muscle, the soleus, shares the Achilles tendon with the gastroc but attaches proximally to the tibia and therefore does not cross the knee.
    The glute/ham bench takes advantage of this anatomy and gives the feet a surface to push against. The weight of the body out in front of the forward pad traps the heels against the roller, allowing the body to be levered up, while the tension of the calves holds the feet against the plate. The plate blocks the ankle extension so that the contraction of the gastrocs is transmitted to the femoral insertions, causing the knees to flex. The glute/ham raise is essentially a back extension until the torso is parallel to the ground, where the hips have extended as well as the spine. Then the feet push the plate, and the knee flexion adds to the upward momentum generated by the back extension, carrying the torso on up to a vertical position, with the knees flexed at 90 degrees, the back and hips in extension, and the chest up.

    Figure 7-52. The glute/ham raise is essentially a back extension followed immediately by a bodyweight leg curl. The knee flexion can be completed because the feet are blocked by the plate, enabling the calf muscles to contribute their proximal function to knee flexion. Without the plate, you won’t be able to fully flex the knees and reach an upright position, as shown in Figure 7-53 .

    The glutes engage more strongly here than they do in a simple back extension. They help generate momentum through the transition between the back extension and the knee flexion. Depending on the individual, the glutes might not be particularly perceptible as they work in the exercise. The trainee might not feel the glutes much because of the huge contribution of the hamstrings working over a much longer range of motion, and because the glutes contract very efficiently over a shorter distance, since their origin and insertion points are not that far apart. The poorer the conditioning of the athlete, especially with regard to the squat, the more noticeable the glutes will be in this exercise. And the poorer the conditioning, the less likely the trainee will actually be able to do an entire set of 10, or