With feet flat beneath bar squat down and grasp bar with shoulder width or slightly wider overhand or mixed grip.
Lift bar by extending hips and knees to full extension. Pull shoulders back at top of lift if rounded. Return weights to floor by bending hips back while allowing knees to bend forward, keeping back straight and knees pointed same direction as feet. Repeat.
Throughout lift, keep hips low, shoulders high, arms and back straight. Knees should point same direction as feet throughout movement. Keep bar close to body to improve mechanical leverage. Grip strength and strength endurance often limit ability to perform multiple reps at heavy resistances. Gym chalk, wrist straps, grip work, and mixed grip can be used to enhance grip. Mixed grip indicates one hand holding with overhand grip and other hand holding with underhand grip. Lever barbell jack can be used to lift barbell from floor for easier loading and unload of weight plates.
In powerlifting, do not squat down too deep and keep shoulder joint slightly behind bar for optimal leverage and mechanics (think 'teeter totter'). Upper body will move back as weight is pulled upward. On rep training, do not merely tap weight to ground, but instead let barbell settle to ground each rep to sufficiently train range of motion through initial slack of heavy barbell. Heavy barbell deadlifts significantly engages Latissmus Dorsi.
Position feet under bar with very wide stance. Squat down and grasp bar between legs with shoulder width mixed grip. Face forward while positioning shoulders upward with arms straight, chest high, hips low, and back straight.
Pull bar up by driving feet outward, while pulling chest up. Extend knees when bar passes knees. At top of lift, when torso is upright, drive shoulders back and chest up. Return weight to floor by bending hips back and knees pointed outward, while keeping chest high and back straight. Repeat.
Use shoulder width grip since narrower than shoulder width grip will make it more difficult to lockout at top. Throughout lift, keep hips low, shoulders high, arms and back straight, and knees pointed out same direction as feet. Also, keep bar close to body to improve mechanical leverage. With wide stance, push feet out to sides and not down to prevent knees from buckling inward. Pushing knees out will allow hips to travel toward bar more quickly while improving leverage.
During rep training for powerlifting, do not merely tap weight to ground, but instead let barbell settle to ground each rep to sufficiently train range of motion through initial slack of heavy barbell. Heavy barbell deadlifts significantly engages Latissmus Dorsi.
See Sumo vs Conventional deadlift stance.
Deadlift uses similar musculature as the Squat in varying degrees, in addition to muscles of the shoulder girdle and forearms to support the load.
The Hips are extended by the Gluteus Maximus and Adductor Magnus. In the lower half the lift, the Hamstrings act as a Dynamic Stabilizers moving through the hips and knee with little change in length. The Hamstrings act more as a Synergist through the upper half of the movement.
The knee is extended by the Quadriceps. The Soleus Planter Flexes the ankle allowing the shin to become upright from the forward angled position at the bottom of the deadlift. The Gastrocnemius acts as a Dynamic Stabilizer, traveling through the ankle and knee with little change in length.
The Spine is held rigid by the Erector Spinae acting as a Stabilizer with the Rectus Abdominis and Obliques acting as Antagonist Stabilizers countering the pull of the Erector Spinae. Under very heavy loads, the spine may tend to flex forward under the weight of a load. The flexion of the spine temporarily decreases the moment arm consisting of the hip and the barbell increasing leverage at this more challenging portion of the lift. If the spine buckles under the weight of the barbell it typically occurs in the thoracic spine. It does not represent a loss of position if this braced flexed position is held until the hips extend near the top of the motion. At this point, the flexed spinal position creates a secondary moment from the shoulders to the hips. This final moment arm gap is resolved by straightening the spine in an upright posture which is facilitated by pulling back the shoulders. This final extension of the flexed spine position requires the Erector Spinae to act as synergists near the top of the motion.
Although many may have issue with such extraneous movement, the spine structures and the accommodating musculature can adapt to these forces with adequate training. To condition the spine in these positions both Dave Tate, world famous champion powerlifter, and Louie Simmons of Westside Barbell recommends both arched back and rounded-back Good-morning in addition to Reverse Hyper-extensions. Also see Adaptation Criteria.
With the torso angled forward in the lower portion of the lift, the shoulder girdle is primarily stabilized by the Middle Trapezius and the Rhomboids, to some degree. When the torso is more upright the shoulder girdle is stabilized by the Middle and Trapezius, Upper as well as the Levator Scapulae.
The Latissmus Dorsi is the primary muscle that pulls the bar closer to the body in effort to decrease the moment arm consisting largely of distance between the barbell and hip.
At first glance of the Deadlift, the Hamstrings appear to work as a Dynamic Stabilizers essentially like they do in the Squat. The beginning and ending positions of the hip and knee are somewhat similar to the squat although the angle of the knee is less in the lower position of the deadlift. However there are subtle differences between the squat and conventional-style Deadlift which make the hamstrings acts as both a synergist and a dynamic stabilizer.
The Hamstrings appear to contract through the hip in the Deadlift, but obviously not to the same extent as they would if the knees where kept totally straight through out the movement (ie: Straight-leg deadlift) since the quadriceps are obviously extending the knee during the deadlift.
The hips begin in a nearly full flexion where as the knees may start in a 75% flexed position (90 degree flexion / 120 degree full-range). Observing beginning and ending joint positions only, that hamstrings appear to act as both a synergist (25%) and a dynamic stabilizer 75% since the net contraction is 100% hip extension (hamstring shortens) minus 75% knee extension (hamstrings lengthens). With this information, it could be argued that the hamstrings could be classified more as a Dynamic Stabilizer than a Synergist since the actual contractions through the hamstrings is relatively small.
|Straight-leg Deadlifts||Full Movement|
|Stiff-leg Deadlift, Romanian Deadlift*||Top 2/3||Bottom 1/3|
|Deadlift||Top Half||Bottom Half|
|Squat, Trap Bar Squat||Full Movement|
*Romanian Deadlift 35-70 degree knee bend (30-60% ROM) , 115-130 degree hip bend (100% ROM)
However, when observing the actual movement of the deadlift (between beginning and ending positions), the majority of knee extension actually occurs early in the lift (allowing the bar to clear the knees), leaving a significant portion of the remaining hip extension to occur nearer the end of the lift with less concomitant knee extension. When the bar clears the knees, the knees and hip flexion are approximately 30-40 degrees (25-33% flexed) and 70 degrees (60%) respectively. These means at this position (bar just above knees), the knees travel from 75% to about 30% flexion (40% full ROM). In this same position, the hips travel from near 100% flexion to 70% flexion (<30% Full ROM). As the lift continues, the knees become nearly straight (increasing hamstring efficiency in effort to partially resolving a active insufficiency of the Hamstrings while the hips continue to straighten.
However since the Hamstrings have entered partial active insufficiency as the hips approach full extension with knees bent, the glutes are still the primary hip extensor although they too are contracting beyond their optimal tension potential.
This means in the early phase of the Deadlift (bar below knees), the Hamstrings act as a 'Dynamic Stabilizer'. However, as the movement progresses (bar above knees), the Hamstrings act increasing like a Synergist (greater net contraction) although a small countering movement through the knees still occurs.
In the lowering phase, the hip and knee movements become more distinct, with significantly less knee bend, particularly until the bar was lowered below the knees. With less knee bend in the initial portion of the in the lowering phase, the hamstrings act more like a synergist during the eccentric phase of the movement.
In the case a competitive powerlifter, the knees never regain their original bend during the actual descent, only bending a maximum of 35 degrees during the lowering phase, as opposed to a 90 degree bend in the initiation of the lift. Since powerlifters don't need to train the lowering phase of the deadlift they commonly either drop the weight part way down or rapidly lower the weight in what could be described as a controlled drop. The 90 degree initial knee bend is only reset after the weight is at rest on the floor. Without the hip and knee bending simultaneously, the hamstrings can act as a synergist in the eccentric phase, however the eccentric portion of a competitive powerlifter's deadlift can be nearly non-existent due to their style of unloading.
The distinction between Dynamic Stabilizer and Synergist is not cut and dry (as with many other classification systems). Other muscles besides the Hamstrings exhibit qualities of both a synergist and dynamic stabilizer.