Short answer: Together squats and deadlifts offer a very powerful formula that can result in decent development of the upper leg as they allow the lifter to overload the quads, glutes and hamstrings with progressively heavier loads.

Nonetheless, naturals promised miracles will have to readjust their expectations as the promoters of 5×5 routines and the likes tend to overhype the power of squat & deads.

Depending on one’s structure and lifting capacity, different versions of the exercises could be deployed to accomplish this goal.

Some leg curling in necessary for complete hamstring development.

The Job of The Squat is To Build the Quads and the Adductors

The main role of the squat in this symbiosis is to build up the leg extenders a.k.a. the quadriceps and the inner thighs (adductors).

Some deadlift variations focus on the legs (e.g., duck stance deadlifts, close-stance snatch grip deadlifts), but even they don’t work nearly as well as the squat for building the quads because the range of motion at the knee joint during a deadlift is relatively short.

One of the ways to tackle this problem is to perform snatch grip deadlifts on a platform, but this hack comes with another downside – the back gets “smoked” long before the quads.

The squat, on the other hand, makes it possible to amass a lot of volume and blast your legs over a great amplitude, provided that you squat deep enough.

The squat also develops the adductors as they act as knee stabilizers and participate in hip extension.

The Main Job of The Deadlift is To Build the Hamstrings

The back squat activates the hamstrings, especially if you go deep, as they are necessary for hip extension, but the quads and the glutes are still the muscles doing the heavy lifting. One is more likely to miss a squat because of weak quadriceps than hamstrings.

Conversely, the deadlift is a heavy hamstring hitter because the lift is super hip dominant and the torso is more horizontal to the ground.

Both Squats and Deadlifts Build the Glutes

The glutes are primary movers in both exercises. However, the deep squat is a better glute builder thanks to the extra range of motion. If your goal is to increase the size of your glutes, and you can do just one exercise, squats are a better choice than deadlifts.

If You’re Squatting for Bigger Legs, Do High Bar Squats

The high-bar squat a.k.a. the classic back squat where you put the bar on top of the traps is more leg dominant than the low-bar version heavily used by powerlifters. The high-bar makes it possible to keep your torso more upright whereas the low-bar position forces you to lean forward significantly and subsequently augments the involvement of the hips at the expense of the quadriceps. Moreover, high-bar squats facilitate deeper squatting.

The only benefit of the low-bar squat beside the higher poundage is the reduced stressed on the knees. Hence why this squat variation may be a good choice for people with knee issues. However, this shift comes at a price – the hips have to work overtime to compensate for the reduced upper leg participation.

The defenders of the low-bar squat will often say that this is a good thing since the hamstrings can do more work, and while that’s correct, the low-bar squat is still an inferior hamstring exercise in comparison to the deadlift.

Another negative side effect of low-bar squatting is the shoulder strain caused by the position of the bar. People who don’t have the necessary mobility could experience shoulder, elbow and even wrist pain.

Combining Different Squat and Deadlift Variations

Option 1: High-bar back squats + Conventional/Sumo/Romanian Deadlifts

High-bar back squats and conventional deadlifts are a classic combo complementing each other. The high-bar squat helps with the initial phase of the deadlift when the quads work the hardest whereas the deadlift builds the hamstrings and ensures balanced leg development.

Option 2: Front squats + Conventional/Sumo/Romanian Deadlifts

The front squat and the deadlift are also a solid team. The front squat is as quad-dominant as a squat can be and has a strong carryover to the start of the deadlift. As a bonus, it also strengthens the upper back which works extra hard to support the weight in front of the lifter. The gained upper back strength has a positive effect on the deadlift lockout.

The benefit that comes from the deadlift is once again the increased hamstring activation which is more than welcomed in this case because front squats do even less for your hamstrings than back squats due to the upright back angle.

Option 3: Zercher Squats + Conventional/Sumo/Romanian Deadlifts

The Zercher squat is very similar to the front in terms of leg involvement. It allows the lifter to squat deep easily and has the greatest carryover to the deadlift out of all squat variations. The Zercher can be done without special equipment, although having a rack is still recommended. The downside of the Zercher squat is that it’s hard on the insides of the forearms and makes the accumulation of volume a highly unpleasant experience.

Which is the Best Deadlift Variation for Hamstring Development?

When doing deadlifts primarily for hamstring growth, it makes sense to push away all quad-dominant kinds and focus on the big three variations – conventional, sumo and the Romanian deadlift.

Conventional Deadlift

Pros

Simplicity. The conventional deadlift is the classic form of the exercise. You’ll find an endless supply of information on it produced by amateur and top-level professionals.

Heavy hamstring involvement. When done properly, the conventional deadlift “destroys” the hamstrings.

Cons

Stressful on the CNS. A heavy deadlift requires serious CNS overclocking and drains the adrenal glands.

Ego-driven. People say that the bench press is the ego lift, but for many skinny brahs that would be the deadlift. It certainly was for me. I have long arms allowing me to deadlift more than usual. I loved the grimaces that people twice my size were making when I was loading the bar with plate after plate. But the glory wasn’t free – eventually, my technique deteriorated. To be more precise, my back began rounding.

When deadlifting for hamstrings, this is bad news. When you lose the arch of the spine, the hamstrings relax and do less work. Hence why many people associate rounding of the back with weak hamstrings rather than back muscles. I’m on the fence about this one. I think rounding is the result of both – weak back muscles and hamstrings.

Sumo Deadlift

Pros

Leg Focus.  The Sumo deadlift places more stress on the leg musculature than the conventional and reduces some of the strain on the back.

Cons

As far as leg development is concerned, the sumo doesn’t come with any major downsides. Some say that it works the hamstrings less than the conventional due to the upright angle of the torso, but a study from 2002 showed the following data in regards to hamstring activation during both lifts:

	Sumo	Conventional
Lateral hamstring	29 +/- 19	28 +/- 19
Medial hamstring	31 +/- 19	27 +/- 19

Judging by the results, the medial hamstring is more active during the sumo pull. This isn’t surprising due to the position of legs.

A while back, the powerlifter Andrey Malanichev switched from the sumo deadlift to the conventional due to hamstring problems.

In other words, the sumo deadlift definitely works the hamstrings hard.

Romanian Deadlift (RDL)

Pros

Heavy hamstring activation. A properly performed RDL places significant stress on the hamstrings.

Smooth control. Out of all deadlift variations, only the RDL creates the opportunity for slow and controlled eccentrics (the negative part of the lift) and smooth reversal into the concentric portion (the positive part of the lift). This makes the exercise great for hypertrophy purposes.

Less ego. The RDL isn’t a competition lift and doesn’t encourage lifters to go crazy with the weight.

Less stress on the CNS. The stretch reflex at the bottom of the RDL and the reduced load make the exercise less taxing on the CNS – a characteristic facilitating the accumulation of volume necessary for growth.

Cons

Tricky to learn. For some people, the RDL isn’t the most natural lift and takes a while to master.

FAQ: What about the Stiff-Leg Deadlift?

It’s a great exercise for hamstring development, but in most cases, it doesn’t offer more than the regular deadlift. After all, the stiff-leg deadlift is just a deadlift done with the hips a little higher than normal in order to reduce the leg (quad) drive and focus on the hamstrings. Truth be told, many people are stiff-legging their regular deadlifts without even knowing it.

The RDL is the Winner

From a hypertrophy standpoint, the Romanian deadlift offers the most benefits. It’s a great movement to pair with the front or back squat.

What About Leg Curls? Are Hip Extension Movements Sufficient for Hamstring Growth?

No.

Exercises revolving around hip extension do not target the short head of the biceps femoris because it does not cross the hip joint. Consequently, a movement such as a leg curl would be necessary to maximize your gains. For the same reason, many people recommend leg curls for knee health.

My experience confirms that the deadlift doesn’t do much to increase your leg curling strength. After my permabulking and powerlifting days, I switched to a bodybuilding routine inspired by Dorian Yates. I was surprised to find out how weak I was on the hamstring curl machine even though my deadlift was pretty decent for my bodyweight and general abilities. If my memory is correct, I had to use the second or third setting from the top to complete the prescribed 8 reps.

References:

ESCAMILLA, R., FRANCISCO, A., KAYES, A., SPEER, K. and MOORMAN, C., 2002. An electromyographic analysis of sumo and conventional style deadlifts. Medicine & Science in Sports & Exercise, 34(4), pp.682-688.