Starting Strength, 3rd Edition - Mark Rippetoe [82]
Figure 4-36. The hip extensors – the glutes and hamstrings and, to a lesser extent, the adductors – initially work only to maintain the back angle as the bar rises from the floor. As the bar approaches the knees, the hip extensors continue to contract, but at this point they begin to actively open the hip angle.
If the hamstrings fail to maintain the back angle, then the butt comes up and the shoulders drift forward, allowing the quads to avoid their share of the work since the knees have extended but the bar has not moved. The bar, however, must still be pulled, so the hip extensors end up doing it all, and in a much more inefficient way. They should be working with the quadriceps through the initial phase of the pull, instead of having to open a much more horizontal back angle at the end of the pull. Either way, the hip extensors work, but their job is easier if the initial contraction controls the back angle and the last part is active concentric hip extension, instead of the whole movement being a long, mechanically hard hip extension. The problem is not that the hamstrings are not strong enough; it is one of motor learning, teaching the muscles to move the bones correctly, in the right order at the right time. The only way to correctly address this problem is to take weight off the bar and make sure you do the deadlift with proper form, with all the angles correct, so that all the muscular contributors to the pull learn to do their jobs in the right order. If you know the actual cause of the problem – and you do now – you can fix it by thinking about squeezing your hamstrings and glutes tight before you pull, thus making them better at doing their job of holding your ass down. If this doesn’t work, think about making your chest move up first, which causes you to fire the muscles that would make this happen; the hamstrings and glutes try to make the chest rise, and this action averages out to a constant back angle.
An interesting thing happens when all the pulling mechanics are correct: the deadlift feels “shorter,” as if the distance the bar has moved has been reduced, compared to an uncorrected, sloppy deadlift. It obviously hasn’t, since the bar moves the same distance either way, but the increased efficiency obtained from the improvement in pulling mechanics is significant enough that the perception is one of a shorter movement. This perception is largely due to the reduction in extraneous hip and knee movement and a consequent reduction in the time the lift actually takes. A correct pull that results from a correct setup will show no change in back angle as the pull starts and for at least the first couple of inches of bar path off the floor.
One of the most common technique errors in the deadlift is using a starting position that attempts to hold the back in a too-vertical position. The method detailed earlier for learning the deadlift eliminates this problem, but hard-headed folks may require further explanation. This misunderstanding of the correct starting position may have several possible causes. One cause might be confusion about the actual role of the back muscles in the deadlift. Some resources on deadlift instruction available in the mainstream certification agency material – intended for fitness/wellness audiences that are not interested in strength – advocate a more vertical back angle than is actually possible for a lifter to use in a deadlift of any significant weight. According to these sources, in an attempt to reduce shear, or sliding forces, between the vertebral segments, you should make the back as vertical as possible so that most of the force on the vertebrae becomes compressive rather than shear. However, shearing cannot occur because the vertebral segments overlap at the facet joints, and sliding between the segments is not anatomically possible. When the erectors