Single-leg work has become much more popular in recent years. Rightly so.
It's invaluable to athletes because it improves unilateral strength, stability and mobility. It also reduces direct spinal loading when performed with dumbbells instead of a barbell on your back.
Still, most lifters use single-leg exercises as supplemental movements in the 8- to 12-rep range (or higher). Split Squats and Lunges are relegated to accessory status far behind any Barbell Squat variation. You will rarely see significant loads moved on one leg for low reps.
The main reason is this: People simply don't know what constitutes decent, good or great unilateral strength. If you believe split squatting a pair of 60-pound dumbbells is something to be admired and represents the pinnacle of your abilities, you will never surpass the 60-pounders. You're banging the top of your head against an imaginary glass ceiling of your own making.
Expectations dictate results. Low expectations generate inferior results. And when it comes to single-leg exercises, the expectations are usually low.
Let's set some unilateral strength expectations worthy of pursuing. This will remove the invisible ceiling impeding your performance. Soon, you'll be lifting weights well beyond what you thought you were capable of.
Strength Standards for Unilateral Squats
It's hard to determine impressive relative strength ratios for Single-Leg Squats because there are no established strength standards in the scientific literature.
Whereas a Barbell Squat double an athlete's body weight represents an established norm for adequate lower-body strength in non-strength athletes, things get muddy when we move to unilateral Squats. If you squat 400 pounds, should you go with 200 on Split Squats because you're using one leg instead of two?
That would seem like a logical approach. But thanks to a phenomenon known as the bilateral deficit, that would likely lead you to drastically underestimate how much weight you're capable of using.
Another factor that makes us think we're weaker than we truly are for single-leg work?
Whether we're aware of it or not, we tend to look at what other people do in the weight room and act accordingly. Aside from my athletes, the biggest weights I've seen people use on single-leg movements at public gyms are the 55-pound dumbbells. It can feel weird split squatting or lunging with a pair of 120-pound dumbbells when the guy next to you uses less than half of that.
So, unless you have instilled the belief on a subconscious level that it's OK to lift far bigger weights than other people do (and it's also safe), you won't maximize your single-leg strength development.
As far as I'm aware, no universally accepted strength norms exist for Split Squats, Bulgarian Split Squats or Lunges. Thus, the responsibility falls on strength coaches to see what their athletes are capable of, then report back on what to shoot for. I believe single-leg squatting is still very much an untapped area when it comes to reaching remarkable levels of strength.
My wake-up moment in this regard came when I interned with NHL strength coach Ben Prentiss back in 2014. I watched Max Pacioretty (then of the Montreal Canadiens) split squat 440 pounds (200 kg) for two reps—using a 7-second eccentric!
Sure, Pacioretty was split squatting with a safety bar which allowed him to grab a pair of handles attached to the power rack, and those handles helped him assist the movement. But there's no denying that's a huge number.
Torey Krug of the Boston Bruins used 400 pounds (around 180 kg) on the same exercise. He's listed at 5-9 and 185 pounds, so he was split squatting well over double body weight on the Hand-Supported Split Squat. Very impressive.
Which leads us back to the question, "How strong is strong enough on unilateral Squats?"
I have noticed that my best hockey players can split squat and lunge over 1.5 times their body weight for five repetitions, unassisted.
For a 200-pound athlete, this translates to 300 pounds. To make the plate math work, we round it up to three plates, which is 140 kilos or 315 pounds. Interestingly, most of my strongest and fastest athletes weigh around 200 pounds and are right around the 300-pound threshold.
Here's Aarne Talvitie, New Jersey Devils prospect and captain of the gold medal-winning Finnish 2019 World Junior Championship team, performing five reps with 140 kg in the Front-Foot Elevated Split Squat at age 17.
Note that the 1.5xBW for 5 benchmark applies to all our main single-leg Squat variations, including Split Squats (both feet on the ground, rear-foot elevated, front-foot elevated), as well as Forward and Reverse Lunges.
As far as difficulty is concerned, Split Squats and Reverse Lunges will be fairly close to each other in terms of how much weight you can lift, followed by Front-Foot Elevated Split Squats. Rear-Foot Elevated Split Squats and Walking Lunges are the most difficult unilateral Squat variations we use, so it will take you longer to hit a 1.5xBW set for five.
As for loading, you can use any piece of equipment that feels comfortable. Your setup could include dumbbells/weight vests/chains, a straight bar, trap bar or U-bar—you name it. What matters is total external resistance and full range of motion, not the implement used.
What about the Hand-Supported Split Squat which seems to have become the go-to single-leg movement in many collegiate strength and conditioning programs? I don't have enough experience with this lift to accurately establish solid strength standards. The fact you can use your hands for extra stability and assistance on the way up makes direct comparisons with unassisted movements difficult.
It's not unlike taking advantage of a bench shirt in powerlifting—you'll lift bigger weights with one than without it. Everyone knows this. But how much more exactly? Nobody can give you an exact number because it varies from one individual to the next.
Benefits of Heavy Single-Leg Work
Gaining general lower-body strength is the main benefit of heavy unilateral squatting. I have seen these gains translate into greater speed and power output time and time again.
Below, pro hockey player Nikolas Matinpalo split squats 341 pounds with the bar in the front rack position. This video was taken at age 19 in his last season of junior hockey before signing with Ilves Tampere in the Finnish Elite League:
And here's Detroit Red Wings prospect Kasper Kotkansalo barbell reverse lunging 319 pounds for a smooth double:
It should not come as a surprise that both of these athletes are fast and powerful. Kasper posted the highest Vertical Jump and fastest 30-meter skating time at the 2019 Detroit Red Wings prospect development camp.
Nikolas owns the highest Vertical Jump and 30-Meter Sprint at his pro club. Both are only 21 years old with plenty of room for further improvement.
While I can't attribute these athletes' superior physical qualities to single-leg exercises alone—we squat, deadlift and power clean heavy on two legs as well, so this isn't another one of those superfluous unilateral versus bilateral Squat debates—being strong all-round certainly doesn't hurt.
The second big benefit I will give heavy unilateral Squats credit for? Reduction in injury occurrence and severity, both in and out of the weight room.
Over the past five years, the number of groin and lower abdominal strains I have witnessed in my athletes is negligible. But if you look at the available research, such injuries are very pervasive in today's professional hockey. It's estimated that each NHL team has 25 man-games lost to groin/abdominal injury per season.
We haven't had a single serious groin injury in five years. And I can remember only four incidences during those five years where a player complained about mild groin pain. All four occurred during hockey season, none in the offseason. In each case, players were back on the ice after taking a few days off from practice while they rehabbed the affected area with targeted strength and mobility exercises.
Maybe we have just been fortunate in this regard. But I believe heavy single-leg Squats have been a major contributing factor to our low number of groin injuries.
Is There a Point of Diminishing Returns?
Although I regard 315 pounds for five reps as the benchmark for sufficient single-leg strength, I'm hesitant to call this "elite"—because, let's be honest, there will always be strength athletes and buff fitness dudes on YouTube posting higher numbers. But for a team sport athlete, repping out unilateral Squats with 1.5 times your body weight is definitely an impressive display of single-leg strength.
I have been hesitant to load guys up much beyond three plates on Barbell Split Squats and Lunges. Assuming an 80/20 weight distribution between the working and supporting leg, 300 pounds on the bar means 240 pounds of resistance on the plant leg. It's a ton of weight to stabilize on one leg. A momentary loss of balance or shift in body position could lead to disastrous consequences.
We must also take into account the additional stress placed on the working leg in a split stance. Forces exceeding what your lower-body muscles can handle puts you at an increased risk of a hip flexor, adductor or hamstring strain—something you rarely see in a bilateral Squat because the weight is distributed evenly on both legs.
This is another reason why so many individuals stick to light weights on unilateral Squats. If you botch a rep holding on a pair of 55s, what's the worst that can happen? It could still be a challenging weight if you have poor relative strength, but the absolute resistance is so light you'll walk away unscathed.
Taking over 300 pounds to town is a whole another animal. A slight blunder at the bottom while holding that much weight on your back will be enough to mess you up. That's not a risk I'm willing to take.
I'm certain some of the athletes I work with would reach 400 pounds quite fast if we made unilateral squatting our top priority and started really pushing numbers up. However, once a 200-pound athlete is capable of split-squatting and lunging in the ballpark of 300 pounds, we have to ask:
"Will adding more external resistance help you become a better athlete on game day?"
I know my hockey players are already plenty strong for the demands of their sport at that point, so the answer is "probably not." They have reached the point of diminishing returns where piling on more strength won't translate into equal gains in speed and power.
Photo Credit: CasarsaGuru/iStock
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