Having previously examined proper technique for the Clean Style Deadlift, I want to look at two related (and often confused) movement that are somewhat related to the deadlift.Those two movements are the Romanian Deadlift (RDL) and the Stiff-legged deadlift (SLDL). Many in the field tend to use these two terms interchangeably but they actually describe two very different exercises.
What’s in a Name?
Before looking at them in any detail, however, I should make one rather pedantic note. The RDL is often referred to more generally as a flat-backed, semi-stiff legged deadlift, a description that will make more sense after I demonstrate how it should be done. So you might be wondering where the name RDL came from.
As the story goes, the Romanian Olympic Lifter Nicu Vlad (who is credited with doing ~300kg, yes that’s 660 lbs., in the exercise) was seen doing them in the Olympic training hall at some point prior to either winning a medal, setting a world record, or possibly both.
Since he was Romanian, the movement got dubbed the Romanian deadlift. Whether that name is ‘right’ or not is ultimately not of much importance in my opinion, RDL is the name most people know the movement by and that’s what I’ll call it.
Both the RDL and SLDL target the same primary muscles which are the glutes, hamstrings and low back (additional work is done by the upper back and gripping muscles). In this context, one of the primary difference between the RDL and SLDL is that the RDL only works the spinal erector muscles statically, as there is no movement in the spine itself.
In contrast, due to the rounding and un-rounding (flexion and extension) that occurs in the SDL, the spinal erectors are trained more dynamically in the SLDL. However, the consequence of this is also a great deal more stress on the low back and spine (including the spinal ligaments and disks); I’ll address this below.
Both the RDL and SLDL start in basically identical positions: both movements start from the top with the bar held with straight arms and the torso upright. A double overhand, mixed, or hook grip can be used, straps can and should be used if grip becomes limiting. I’d note that body movements can be done with dumbbells as well although I’ll only demonstrate the barbell version here.
From that point on, the similarities basically end. In the SLDL, the bar moves out in front of the body (the legs generally stay locked and the hips don’t move) and the bar is generally brought quite low, usually to the instep of the shoes; this usually necessitates standing on a high platform so that the plates don’t hit the ground (in the picture below, the lifter isn’t on a block since there were no weights on the bar). The back will be very rounded at the bottom of the movement due to the protracted range of motion. Lifting the bar is simply a reversal of the lowering, the low back unrounds as the lifter’s torso comes back to the upright position.
I’d note that another variant of the SLDL (not shown in this article) does not take the bar as low, and the back stays flat. In my experience, most take an SLDL to the instep which requires rounding the low back which is why I’ve focused on that variation in this article.
In contrast, with the RDL the back remains flat or slightly arched, the knees are typically bent slightly (about 10-20 degrees) and the hips move backwards with the shins staying more or less vertical, the weight should be back on the heels. As you can see below, the bar doesn’t go nearly as low in the RDL as in the SDL as a consequence of the low back not rounding.
A side by side comparison of the bottom position of a typical SLDL (left) and RDL (right) appears below. Note that, if there were plates on the bar, the SLDL would require standing on some type of high platform (a flat bench is typically used) so that the plates don’t hit the floor. Again, there is a variation of the SLDL where the back remains flat, but the bar is still swung out front without the hips moving.
In the RDL bar is only lowered as low as the lifter can go without rounding the low-back, for most people this usually puts the bar just below the kneecap. However, I have seen the very occasional person with freak hamstring flexibility or exceedingly long arms go lower than this and keep their back flat but for most just below the kneecap is about the limits.
In my experience, even with 45 pound plates or bumpers on the bar, the plates will rarely touch the floor in a properly done RDL unless the lifter is unusually flexible or has very long arms. In that case, the lift will have to be done standing on some sort of raised surface (e.g. an aerobics step) so that a full range of motion can be achieved.
Extremely inflexible lifters will stop higher and the RDL can actually be used as an excellent hamstring stretch (with just the bar or a small amount of weight). The bar should simply be lowered to the limits of the lifter’s hamstring flexibility (with the back kept flat/slightly ached) and that position held. The weight of the bar will gradually pull the lifter into a deeper position, stretching the hamstrings in a very functional pattern. Over time, the range of motion of the RDL should increase until the proper bottom position (again, bar slightly below the kneecap) is reached.
The upper back should be set and locked during the entire movement with the lats flexed (this will improve low back stability) and the shoulder blades pulled back, the bar should basically slide down the legs and over the knee. As the bar is lifted, it slides back up over the knee and then back up the thighs. That bar is essentially dragged up and down the thighs and should never ‘swing out’ from the body.
The below two pictures show a proper depth RDL (left) with the lifter having gone a little bit too low (right). Note how there is flexion in the lower back area in the right picture with no change in hip position. That is to say, the extra depth is accomplished by rounding the back, there is no additional movement at the hip.
One easy way to avoid rounding the low back is to keep the head up (and neutral to your torso, don’t hyper-extend your neck) with the movement done in front of a mirror. If you can still see yourself in the mirror, your head is up and your back won’t be rounded.
In contrast, if you can’t see yourself anymore, you’ve dropped your head and have rounded either your upper back, lower back or both. If you feel the tension come off of your hamstrings and into your low back, you’ve probably rounded your back as well. It’s also possible that you’ve bent your knees which will also take tension off of the hamstrings.
For the most part, I’m not a big fan of the SLDL except as a light stretching or warm-up exercise. The problem is this: as the low back rounds beyond a certain point, the low back muscles (spinal extensors) become inactive due to an inhibitory reflex; this throws all of the stress onto the ligaments of the spine. As well, spinal flexion under load can be damaging to spinal disks in the long-run, increasing the risk of disk herniation.
While I know many have done heavy SLDL’s over the years, I can’t recommend this based on what we know about spinal health. In a future article, I’ll detail what I think is a better way to train the spinal muscles dynamically, which is various types of back extensions.
Basically, I think that the RDL is the superior movement here. Olympic lifters use it as an assistance exercise (to mimic the second pull) and it can be done with either a clean or snatch grip, athletes and powerlifters use it to strengthen the posterior chain to improve squats and their deadlift lockout, and bodybuilders can use it to hammer their hamstrings and glutes. Basically, I think it’s safer (from the standpoint of spinal health) and a more effective movement in the long-term.
As far as programming, both the RDL and SLDL are generally better used for moderate reps, unless a lifter is very technically skilled. Reps lower than three tend to be problematic, invariably lifters get a little bit freaked by the heavy weights and do funky things technique wise, I don’t think I’ve ever had a lifter test a maximum single in the RDL, nor would I.
Sets of 5-8 are generally the best way to go for most lifters and the RDL/SLDL is usually used as a secondary leg exercise following squats or deadlifts. Higher reps can be done but lifters have to be aware of signs of upper back fatigue and form breakdown. With the RDL this causes rounding and a loss of proper technique.
I’d note that RDL’s do involve a lot of low back even though the spinal erectors aren’t being used dynamically. If a lifter has exhausted their low back with heavy deadlifts or power style squats, RDL’s may be a real problem technically as the low back will give out. Keeping the weights lighter or picking a me that doesn’t involve so much low back may be a better option here.
Finally, it’s worth mentioning that RDL’s are notorious for causing some pretty crippling hamstring soreness. The hamstrings are often prone to soreness in the first place and the high stretch component of the RDL tends to exacerbate this. Just something to keep in mind when you introduce the movement (or re-introduce it after a long-lay off); start light or you may not be able to walk for 5 days.
- Back Extension Technique
- Round Backed Deadlifts Another Look
- Clean Style Deadlift Technique
- Leg Curl with Hip Extension
- Split Squat Technique