Starting Strength

stable configuration is probably very close to 90 degrees. What is absolutely clear is that through the bottom of the pull, there exists a back angle in which the shoulders are in front of the bar, the arms do not hang straight down, the hips are closer to the bar than they would be if the arms did hang straight down, and pulling the bar off the floor in this position results in a vertical bar path. With this path, the lifter can most efficiently maintain the balance point over the mid-foot and use the lats and related muscles to maintain a vertical bar path.
    Stated more succinctly, the arms are not plumb in a deadlift because the lats do not attach to the arms at 90 degrees when the arms are plumb . The arms must slant back to achieve a position of stability as they hang from the shoulders. So the body must assume a position that allows the arms to be at 90 degrees to the lats and for the bar to be pulled in a straight vertical line off the floor. If the hips are too low, the lat attachment angle will be less than 90 degrees, and the hips will rise as the back angle adjusts to the stable position. If the hips are too high, the angle is greater than 90 degrees, and the lifter cannot as efficiently prevent the bar from continuing forward.

    Figure 4-25. A proof of the theory that the lat stabilizes the humerus most efficiently at 90 degrees, from our friend Matt Lorig, Ph.D. This is the kind of analysis you get when you ask a physicist to think about barbell training.

    Figure 4-26. The skeletal relationships in the pull off the floor with arm angles of 90 degrees (I), < 90 degrees (II), and > 90 degrees (III).

    The reference angles used in analyzing the deadlift are the same as those used in analyzing the squat. The hip angle is formed between the femur and the plane of the torso. The knee angle is formed between the femur and the tibia. The back angle is formed between the plane of the torso and the floor, which is assumed to be horizontal. In a correct deadlift, the knees extend as the bar comes off the floor, indicating that the quadriceps extend the knees under load. The back angle should be constant until the bar approaches the knees; the hamstrings “anchor” the pelvis so that this angle can be maintained (more on this later).

    Figure 4-27. The three reference angles: knee angle, hip angle, and back angle.

    The hip angle opens up only slightly as the tibias get more vertical. As the bar approaches the bottom of the knees, the back angle – and consequently the hip angle – begins to change significantly ( Figure 4-28 ). Some people start this transition at mid-shin, some higher, as there appears to be quite a bit of individual variability in the precise position of the beginning of this shift. Anthropometry is probably an important variable; arm length, for example, obviously influences this balance relationship. In most snatches and cleans, this back-angle shift appears to start a little higher up the tibias – very close to the knees for most good lifters – than it does in deadlifts, so it may be a function of the relative load. The “shorter” arms and wider grip in the snatch may mitigate the lighter weight used relative to the clean. The function of the lats changes here, as the back angle becomes more vertical and keeping the lifter/barbell system in balance over the mid-foot becomes a function of the increasing back angle, and less dependent on lat tension. In all pulls from the floor, this is seen in the bar path, which always tends to come back over the mid-foot even if the bottom of the pull has been inefficient.

    Figure 4-28. The correct sequence off the floor. (A) The starting position. (B) Knees extend, opening the knee angle. (C) The hip angle opens, bringing the bar up to the finish position (D).

    As the hips extend more, the hip extensors – the glutes, adductors, and hamstrings – become the predominant movers of the load, the quads having finished most of their initial job of extending the knees before the bar gets to them. The role of the back muscles during the pull is to hold the trunk rigid and keep the shoulder blades back in their normal anatomical position so that the force generated by knee and hip extension can be transferred up the back, across to the arms, and down to the bar. Lockout at the top occurs when the knees and the hips reach full extension simultaneously, with the chest up and the shoulders back. If this pulling sequence is followed, the bar will come up