I think it is safe to say most would agree that deadlifts are great for building maximal lower body strength. Elite Olympic weightlifters are generally able to lift more loads in this lift compared to other free weight exercises.  I know personally that I like to use it to develop lumbar extensor strength, as well as in place of the squat if I want to avoid spinal compression from the weight of the bar.

In the past I have heard some strength coaches say they don’t use a hex bar for deadlifts because it is not the same as lifting a straight bar.  While not always sure exactly what they mean by that, I found a recent article in the July 2011 Journal of Strength & Conditioning Research very insightful.  The researchers looked at the difference between straight and hexagonal bar deadlifts in submax loading situations.

The concern with deadlifting has always been stress on the spine.  The study notes:

“For world class athletes lifting extremely heavy loads, lumbar disk compression forces as large as 36,400 N have been reported.”

Lifters have long been encouraged to keep the barbell as close to them as possible to reduce the moment arm. The issue with the straight bar is that it can impinge on the body.  Thus, the trap bar or hex bar apparatus was developed.  The researchers hypothesized that the hex bar would reduce the joint movements and resistance moment arms.  In addition, they hypothesized that larger forces would be produced with the submax loads.

The study use 19 male powerlifters and was conducted 3 months after their most recent competition where most were at the end of a training cycle aimed at matching or exceeding their previous competition performance.  The subjects (following their own warm-up) performed HBD and SBD at 10, 20, 30, 40, 50, 60, 70 and 80% of his SBD 1RM.  Twelve markers were placed on the body for biomechanical analysis.


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