Dead lift

The deadlift is a weight training exercise in which a loaded barbell or bar is lifted off the ground to the level of the hips, then thrown to the ground. It is one of the three powerlifting exercises, along with the squat and bench press.

Deadlift refers to the lifting of dead (without momentum) weight, such as weights lying on the ground. It is one of the few standard weight training exercises in which all repetitions begin with dead weight. There are several positions one can approach when performing the deadlift, which include the conventional deadlift, squat and sumo-deadlift. In most other lifts there is an eccentric (lowering of the weight) phase followed by the concentric (lifting of the weight) phase. During these exercises, a small amount of energy is stored in the stretched muscles and tendons in the eccentric phase, if the lifter is not flexible beyond the range of motion.

Conventional deadlift: The deadlift can be broken down into three parts: The setup, the initial pull or drive, and the lockout.

Setup: When performing a deadlift, a lifter will set up in a position that eccentrically loads the gluteus maximus, minimus, biceps femoris, semitendinosus, and semimembranosus while the muscles of the lumbar contract isometrically in an effort to stabilize the spine.

Drive: The next section of the deadlift produces the highest amount of force. By pushing down through their heels while simultaneously pushing up and forward with their hips and maintaining depressed scapula and a long tense spine an individual can remain safe during this motion. This is considered the most difficult part of the entire movement due to the amount of work required to drive the bar off the ground initially.

Lockout: The finish is the most critical aspect of the motion. This requires being totally erect with the spine and forceful hip extension to engage the muscles of the lumbar spine and abdomen in unison with the glutes.

Lowering the weight: Finishing a deadlift is simply performing these same steps in reverse order. As the muscles of the back and core must remain tight throughout the motion, one should simply hinge at the hips and knees to bring the weight down. Lowering their chest towards their knees while keeping the bar close is the safest way to ultimately complete the motion.

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Wikipedia