What is the difference between RDL and Stiff Legged Deadlift?

When it comes to strength training and building a well-rounded physique, deadlift variations are often regarded as the kings of compound exercises.

Among these variations, the Romanian Deadlift (RDL) and the Stiff-Legged Deadlift (SLDL) are frequently discussed and sometimes confused due to their similarities.

However, each exercise offers distinct benefits and targets different aspects of muscle development.

In this article, we will delve into the nuances of these two powerful lower body exercises, highlighting their differences, benefits, and how to properly perform them.

The Romanian Deadlift (RDL)

The Romanian Deadlift, often referred to as the RDL, is a compound exercise that primarily targets the glutes, followed by the hamstrings and lower back muscles.

It’s known for its effectiveness in building strength, improving posterior chain development, and enhancing hip hinge mechanics.

The key differentiator of the RDL is that it emphasizes more of a knee bend to the point where the shin remains relatively vertical. As I’ve learnt from Paul Carter, due to the knee bend, this disadvantages the hamstrings making the glutes the prime mover. But this does not mean it’s zero hamstrings.

How Do You Perform an RDL:

Begin with your feet hip-width apart, hold a barbell or dumbbells in front of your thighs with an overhand grip.

Hinge at your hips while maintaining a neutral spine. Lower the weight towards the ground, ensuring that you push your hips back and maintain a slight bend in your knees so that the shin can remain vertical.

Lower the weight, the bar will match up with the shins once the bar has cleared your knees.

When you can no longer push your hips back, cut the range of motion.

Reverse the movement by driving your hips forward and straightening your body back to the starting position.

Here’s a great example of an RDL where the shin remains vertical:

The Stiff-Legged Deadlift (SLDL)

The Stiff-Legged Deadlift, or SLDL, is another deadlift variation that targets the hamstrings followed by the lower back and glute muscles.

However, its execution and focus differ from the RDL. The SLDL places a greater emphasis on hamstrings as the legs remain stiff, hence the name.

Because the legs are stiff, the shin won’t remain vertical but slightly drift back into a negative shin angle.

How Do You Perform The Stiff-Legged Deadlift (SLDL)

Stand with your feet hip-width apart, hold a barbell or dumbbells with an overhand grip.

Keeping your legs relatively straight by holding more of locked knee (not to be confused with hyperextended knee), hinge at your hips and lower the weight towards the ground. Focus on maintaining a neutral spine throughout the movement.

Lower the weight towards the ground letting the bar travel over the middle of the foot – note: the shins will NOT match up with the bar like they do in the RDL, there will be a noticeable distance between the shin and the bar.

Push your hips back. You will feel a big stretch in the hamstrings.

Reverse the movement by driving your hips forward and returning to the upright position.

Here’s a great example of the negative shin angle that occurs during the SLDL:

RDL vs SLDL Range Of Motion

Many will argue that the only difference between the two is the range of motion.

That being, the RDL is a smaller range of motion with constant tension and the SLDL starts from the floor with dead weight.

Again, the difference between the two is the degree of knee bend.

If the legs remain straight, but the plates don’t touch the ground – it’s still a SLDL because the legs are STIFF. Some may call a shorter range of motion SLDL a ‘hamstring biased RDL’, and that’s completely fine, don’t get too caught up in the names.

Likewise, is someone has the ability to perform the RDL all the way down to the floor and hold a vertical shin, it’s still an RDL because the knees are unlocked.

More knee bend = RDL = more glutes

Less knee bend = SLDL or ‘hamstring biased RDL’ = more hamstrings

What’s the difference between an RDL and Deadlift then? In the deadlift the knee’s will continue to bend and the shin will push into a positive shin angle.

How to Spot The Difference Between The RDL vs SLDL

From the side you’ll notice two things:

RDL – the shins will remain vertical (note the red line) and there will be very little distance between the shins and the bar.

SLDL – the shins will drift back into a negative shin angle (note the red line) and there will be a noticeable distance between the shins and the bar (note the yellow line).

In the realm of strength training and muscle development, understanding the nuances of different exercises is crucial for making informed decisions about your workout routine.

The Romanian Deadlift (RDL) and the Stiff-Legged Deadlift (SLDL) are two variations of the deadlift that, while similar, differ significantly in execution, emphasis, and benefits.

Incorporating both exercises into your training routine can provide a well-rounded approach to building strength, and enhancing muscle development.

Whether you prioritize RDL for more glutes or the SLDL for more hamstrings, both exercises offer unique advantages that can contribute to your fitness journey.

Remember to always prioritize proper form and gradually increase weights to ensure safe and effective progress.

Oh by the way, whenever you’re ready, here are 3 more ways I can help you:

1. Grab a free copy of my new workout program, Athletic Curves

If you’ve been exercising more and eating less and still stuck in a plateau then you need the simple 4 week workout that builds a strong, fit and athletic hourglass figure. Download your copy here.

2. Join GWL with Grant connect with girls who lift from around the world

It’s our new free Facebook group where girls who lift from all around the world can chat, learn and inspire each other. Click here to join.

3. Get technique feedback from me
If you would like me to take a look at your lift and offer some tips, just send your video to one of my social media accounts linked down below:


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About The Author

Grant Lofthouse

Grant Lofthouse is personal trainer with over 10 years experience who helps his clients break fat loss, muscle building and strength plateaus by using simple strength and nutrition systems.