Starting Strength

between the bar and the mid-foot balance point. This completes the concept presented in Figure 2-7 – the extra effort is due to the existence of the moment arm between bar and midfoot. ( M.A. = moment arm )

    Figure 2-32. The concepts of moment force applied to the body during the squat. (A) The moment force A, along the segments, is inherent in performing the motion of squatting and is thus the force against which we exercise. (B) The moment force B, between the bar and the mid-foot balance point considered vertically, must be kept to ZERO for greatest efficiency. Moment force B adversely affects the work done against moment force A. ( M.A. = moment arm )

    Common Problems Everyone Should Know How to Solve
     
    A correct squat will always have certain identifiable characteristics controlled by skeletal anatomy and muscle function. For any squat, back or front, these conditions will be satisfied, making it relatively easy to determine whether form and position are correct. At the top, all the skeletal components that support the bar – the knees, hips, and spine – will be locked in extension so that the muscular components have to exert only enough force to maintain this position, in which compression is the primary force on the skeletal components. The job of the muscles here is to keep the bones lined up correctly so they can hold up the load. The bar will be over the middle of the foot. The heavier the weight, the more critical this position will be.
    When the squat begins its eccentric phase, all the muscles that will ultimately extend these joints – or in the case of the spinal erector muscles, isometrically maintain extension under increasing stress – come under mechanical load as they resist the leverage along the segments on the way to the bottom position. During this ride to the bottom, the bar must maintain its position over the mid-foot. The correct bottom position is identified by definite anatomical position markers:
     
The spine will be held rigid in lumbar and thoracic extension.
The bar will be directly over the middle of the foot.
The feet will be flat on the ground at the correct angle for the stance width.
The thighs will be parallel to the feet.
The hip joint will be in a position lower than the top of the patella.
    Any deviation from this position will constitute bad technique, as will any movement on the way down or back up that causes a deviation from this position. And actually, if you keep the bar in the correct vertical position over the mid-foot on the way down and back up – as if the bar were riding in a narrow slot directly plumb to the mid-foot – you will have done it right. Your skeleton will have solved the problem of how to most efficiently use your muscles to get the job of squatting done. It will have done so within the constraints imposed upon it by the mechanics of the barbell/body/gravity system.
    The position of the bar on the torso will control the angle of the back, and the angle of the back and the stance will control the forward or back position of the knees. When the bar is in the front squat position, the back will be quite vertical because this angle is necessary to keep the bar over the mid-foot and to prevent it from falling forward off the shoulders. When the back is this vertical, the hips are nearly directly under the bar, a position which forces the knees well forward in front of the toes and which the ankles must accommodate by allowing the tibias to incline ( Figure 2-33 ). This means that for the front squat, the back angle will be nearly vertical, the hip angle will be open, and the knee angle will be closed. For the back squat, when the bar is in the position advocated here, just below the spine of the scapula, the back will be at a much more horizontal angle, and the knees will be at a point just in front of the toes (depending on your anthropometry), so that the hip angle will be more closed and the knee angle more open. A high-bar squat would place the back and knees in the middle of these two more useful positions.

    Figure 2-33. Bar position ultimately determines back angle, as seen in this comparison of the front squat and the squat. Note that the bar remains balanced over the mid-foot in each case, and this requires that the back angle accommodate the bar position. This is the primary factor in the differences in technique between the two styles of squatting.

    Every barbell exercise that involves the feet on the floor and a barbell