Romanian Deadlift (RDL) vs. Stiff Legged Deadlift or Straight Leg Deadlift (SLDL)

In the past month it seems like I have run into at least a half dozen people performing what they thought was a Romanian Deadlift (RDL), at least that has always been what they say they are doing. I am not sure if it has become more popular as of recent or I have noticed it more but unfortunately most of the athletes were not performing the movement they thought they were. In most cases they were doing something closer to a Stiff Legged or Straight Leg Deadlift (SLDL) rather than a Romanian Deadlift (RDL). This is a problem I have encountered many times over the years but with more frequency recently so I thought it was time to address it. 

Somewhere along the way, clients and trainers began thinking that a Romanian Deadlift is a straight weight to floor movement but it really should not be, that is more appropriately termed a "Stiff Legged" or "Straight Leg Deadlift".  Even a  a Straight Leg Deadlift usually doesn't get lowered all the way to the floor.  As all these are movements designed to work the hamstrings, each athlete needs to gauge their own flexibility and range of motion. 

Many people think the moves are similar but when performed correctly they are very different...

Origins

First of all let’s get some history straight as to where the RDL came from. There was a very famous weightlifter from Romania that was visiting the Olympic Training Center named Nicu Vlad. He had a tremendous amount of strength in the powerlifting movements and he was seen performing a new exercise that accentuated the eccentric portion of a deadlift movement (lowering portion in this case), while maintaining a neutral lower back thus less strain. Not knowing what to call this exercise the weightlifters that saw this named it a “Romanian” Deadlift since Vlad was from Romania. So if you aren’t doing it the way Vlad did it, are you actually doing a Romanian Deadlift (RDL)?  Maybe, it depends on who is coaching.  That being said, more important is the intention of the movement and the risk reward profile.

Over the years many variations have popped up and what you name a movement is not as important as the intention of the movement.  As such I am going to explain both the intention as most experts agree today and the variations that are acceptable and how to distinguish them.  Lastly I will tell you which one I think is best and why.

The Movement

First of all let's distinguish the key elements of a deadlift.  The deadlift is a movement whereby the athlete pulls the weight off the floor by squatting down and standing up.  I am going to trust that anyone reading this has seen or performed a deadlift.  The key is that a deadlift is almost completely a concentric muscle movement.  What that means is that most of the work is performed by the muscle while fighting gravity as the posterior muscles contract during the lifting phase.  The eccentric or lowering part of the movement in this case, is often performed very rapidly or in some cases the barbell is dropped to the mat.  If the athlete lowered the barbell back down with the same or slower speed in which they lifted it, the hamstrings would get more work during the eccentric phase, but doing this would put the athlete's lower back at risk for injury.  Thus a faster release or dropping of the weights is often see at heavier loads.  The RDL is the solution to the problem of training the eccentric phase of the deadlift while minimizing risk of injury to the lower back.

Muscles Groups

The RDL and SLDL target the same primary muscles, the glute (butt), hamstrings (back of thigh) and the lower back (additional work is done by the upper back and gripping muscles). The biggest difference is in how the lower back muscles are stressed which is dictated by the correct form and technique of each movement. The three types of back muscles that support and move the spine are the extensors, flexors and obliques.

• The extensor muscles are attached to the posterior (back) of the spine and enable standing and lifting objects. These muscles include the large paired muscles in the lower back (erector spinae), which help hold up the spine, and gluteal muscles.
• The flexor muscles are attached to the anterior (front) of the spine (which includes the abdominal muscles) and enable flexing, bending forward, lifting, and arching the lower back.
• The oblique muscles are attached to the sides of the spine and help rotate the spine and maintain proper posture.

The biggest difference between the RDL and the SLDL is how those lower back muscles are stressed especially the small spinal erector muscles or erector spinae. These smaller muscles fan out and up the spine and are more tendinous in structure along the sacral region (lower back). In other words, along the lower back they look less like the belly of a large muscle and look more like a fibrous tendon. This means they are more prone to tearing as they don’t stretch as well and are less pro-fused with blood meaning they heal slower if injured. In the RDL, the spine stays in a neutral or static position thus the lower back muscles are not in acute stress when performed correctly. In the SLDL the spine is in some level of flexion (bending or rounding) depending on knee flexion (bending) and thus the spine is more stressed increasing the potential for injury of tendons, ligaments and disks.

Form and Technique

The biggest notable difference in this movement is the rounding of the back that inevitably happens with a SLDL. In its most simple state, the Straight Leg Deadlift is similar to a movement where you attempt to bend over and touch your toes without bending the knees but with weight in your hands. In a slightly modified version, the Stiff Legged Deadlift, the knees have slightly more bend but the movement still stems from the bending of the torso. So the stiffer the legs and the less bending of the knees, the more bending forward at the torso/lower back (flexion) or lifting back up (extension) the same way. In addition the range of motion in both movements takes the weight from the ground into a standing position and back down again. In a RDL the range of motion should be limited to a comfort level usually just below the knees and then back to standing. You should not take a RDL to the ground!

Loading  a rounded back means you are pulling weight while in a contracted state which is a recipe for an injury.  Although you could reduce the range of motion the likelihood of rounding the back at the bottom is almost inevitable with a SLDL.  Put enough weight on this movement and the risk for a muscle or disk injury is significant and the risk return for this exercise is minimal and not one I would use with most athletes. There are better ways to exercise the posterior chain with an eccentric movement while stretching the hamstrings.  Enter the RDL...

You will often hear that the RDL sets up the same as the SLDL but that is because everybody starts both exercises with the barbell on the ground. But if you want to perform the RDL properly you should start with the barbell in the rack just above your knees.   If you don't have a rack you should properly deadlift the weight up before beginning a RDL.  Thus the movement begins with the lowering or eccentric stretching phase of the posterior chain (hamstring and glutes).  Performing the RDL properly means you start from the standing position, you lower the weight to a comfortable position just below the knee that fully engages the eccentric movement of the deadlift stretching the hamstring.  Keep the knees loose and slightly bent at about 20+ degrees and move the hips back while maintaining the spine in a static or neutral position and then thrusting the hips forward and standing back up with the weight.  Additionally the barbell stays in contact with the thighs whereas in the SLDL the barbell hangs out a little further thus also compromising the lower back.  Eyes are straight ahead with a slight downward gaze and chest remains high.

In general the RDL is very different than the two versions of the SLDL and when performed correctly should never risk injury to the lower back. The lower back should remain in a healthy lumbar curve (half moon) or neutral position vs a rounded or humped shape. In short the RDL when performed properly is both safer and healthier for the back giving the athlete a better risk return performance profile.

Below are some more finer details on the various forms of the RDL from some of the highest recognized weightlifting experts in the health and fitness field; Bret Contreras and Mark Rippetoe.  When in doubt make sure you get your information from a reputable source!