Starting Strength

the legs in a vertical path.
    If the back rounds during the pull, some of the force that would have gone to the bar gets eaten up by the lengthening erectors. If the weight is sufficiently heavy, the rounded back cannot be re-straightened and the deadlift cannot be locked out; the spinal erectors are designed to hold an extended position isometrically, not to actively extend a flexed spine under a compressive load. The knees and hips are already extended – the knees in this position are straight and the pelvis is in line with the femurs – and their extensors cannot help since they are already fully contracted.

    Figure 4-29. A rounded lower back is difficult to straighten when the weight is heavy. The muscles that hold the lumbar spine in extension are postural and are not designed to change the relative positions of the vertebrae; their job is to maintain extension, not to concentrically extend under compressive loading. And if the spine is in flexion, the hips are, too. If the hip extensors have finished their job, the pull is essentially finished. The only way to continue the pull would be to “hitch” the bar with a knee re-bend that would allow the hip position to reset a little. Many heavy deadlifts have been missed this way.

    The question of exactly what these three angles should be is answered for each person individually since it depends on individual anthropometry. People with long femurs, long tibias, and relatively short torsos will have a more horizontal back angle and a more closed hip angle than people with long torsos and short legs, who will have a more vertical back angle and a more open hip angle. Each person will have a different set of knee, hip, and back angles, but the correct starting position for everyone will have the previously discussed things in common: the shoulders will be slightly in front of the bar; and the bar will be touching the shins directly over the mid-foot, resulting in the vertical alignment of the scapula, bar, and mid-foot. If this alignment is correct, and if the arms are straight, the feet are flat on the floor, and the back is in good thoracic and lumbar extension, the resulting reference angles are correct for that person’s anthropometry. Of the three angles, the back angle will exhibit the most obvious individual variability, easily seen by an informed observer.

    Figure 4-30. A comparison of different anthropometries in the deadlift start position.

    Arm length must also be considered when you are analyzing these angles. All other segment lengths being equal, short arms produce a more horizontal back angle and long arms produce a more vertical back angle. Long arms tend to mitigate the effects of a short torso, while short arms and a short torso make for a nearly perfectly horizontal back. To balance the effects of short arms and a short torso, people with this build might need to use a sumo stance, since a wide stance produces the more vertical back angle typically seen in people with more typical proportions.

    Figure 4-31. The effect of different variations of back and leg dimensions on the back angle in the starting position. From left to right, back length increases as leg length decreases.

    Most of the problems you will have with deadlift form can be analyzed with a good understanding of pulling mechanics. Consider, for example, the problem of lowering the bar with a round back, caused by unlocking the knees first: the down phase is the exact reverse of the pull. If the last thing that happens at the top of the deadlift is the simultaneous extension of knees and hips, with a locked back and the chest up, then the first part of lowering the bar has to be knee and hip “un-extension” with a locked back and the chest up ( Figure 4-32 ). The knees unlock just enough to take the tension off the hamstrings, at exactly the same time that the hips unlock. Then the butt travels back with the lower back locked, as the lifter closes the hip angle and uses the hamstrings and glutes eccentrically as they lengthen. As the bar slides down the thighs, further closing the hip angle, it reaches a point as it passes the knees where the knee angle can begin to close with the hips. As the bar is lowered past the knees, they bend and the quadriceps add to the hamstrings’ eccentric function, and the bar gets to the floor. This sequence of movements – the opposite of the pulling-up sequence – allows the bar to drop down in a vertical line ( Figure 4-32 ).

    Figure