The Power of Unilateral Training for a Bigger, Stronger Physique

“What’s the point of doing an exercise one side at a time?”

If you’ve ever wondered about this, or heard your clients ask, you’re not alone.  At first glance, unilateral training can seem inefficient. It takes twice as long to complete a set, and the exercises are often more challenging to master.

So why bother?

The reason you should not overlook unilateral exercises is because they have unique advantages that bilateral lifts can’t match. And understanding these advantages is a must if you want to level up your program design skills.

And yet, most programs sprinkle in a few token split squats or one-arm rows without really understanding how powerful unilateral work can be when applied intentionally.

By the end of this article, you’ll have a sharper understanding of unilateral training’s role in strength and hypertrophy, and know exactly how to use it to deliver next-level results for your clients.

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Point 1) Unilateral exercises can be more specially tailored to fit your clients anatomy

One overlooked advantage of unilateral work is the ability to move naturally,  without being forced into fixed positions that stress the joints.

When using a barbell for exercises like curls or presses, the hands are locked into a rigid path. This might seem harmless at first, but over time, even slight joint misalignments at the wrist, elbow, or shoulder can lead to irritation, inflammation, and eventually injury.

In contrast, using dumbbells or other independent loading lets each arm find its own optimal path based on individual structure, reducing unnecessary joint stress and promoting healthier long-term movement.

Quick test:
Stand up and rotate your palms to face forward (supination).
Notice the natural angle of your forearms relative to your torso. Are they perfectly straight? Slightly angled outward? Everyone’s bone structure is a little different, and your exercise setup should respect that.

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Another niche example of where unilateral exercises are often favored is for those training around pain and injury. 

For example, if you have ever trained a client who is in the process of recovering and rehabbing from a lower back injury such as a disc herniation, one thing you will often encounter is pain during bilateral lower body lifts such as squats and deadlifts.

Does that mean they have to avoid lower body training? Absolutely not! More often than not, they can still tolerate unilateral exercises like step-ups and split squats.

This happens because the nerve roots are pulled differently during bilateral and unilateral movements. With bilateral lifts, the nerve roots are pulled from both ends, increasing neural tension and often aggravating pain.

In contrast, with unilateral movements, only one end of the nerve is being tugged, making it far more tolerable and often pain-free.
Think of someone playing tug-of-war with a rope, and think about how much tension that would build when both sides are pulling, versus just pulling from one end.

To play devil’s advocate, I’m not saying every client needs to be handled with extreme delicacy. The human body is incredibly resilient.

However, you will or likely already work with clients who are more sensitive to subtle joint positions, and it’s your job as a coach to mold the program to fit them, not force them to fit the program.

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Point 2) Unilateral training improves neural drive to the working muscles

Your muscles contract because of an electrical signal called an action potential. This signal travels from the brain, through the brainstem and spinal cord, down the specific nerve, toward the muscle, where it activates motor units that trigger contraction.

If we think of this travel as a highway, then you can imagine that this highway would be split down the middle if we were to, for example, contract both of our hamstrings at the same time.

This split is responsible for what’s known as the “bilateral deficit”.

The bilateral deficit simply states that both sides of the body working together are often weaker than the summation of the work done by each side individually.

Understanding this phenomenon helps explain why unilateral training can often work better to develop strength and size over time.

In our article on building strength and size simultaneously, we explained that intramuscular tension is the primary driver of hypertrophy. If unilateral training allows us to challenge muscles with heavier loads through improved neural drive, it stands to reason that unilateral work can be a potent tool for muscle-building.

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Here’s the caveat: This doesn’t apply to every exercise.

You have to use your noggin’ for this one. In some cases, unilateral exercises create too much instability, limiting the potential for loading heavy enough to drive real progress.

A good example is a unilateral dumbbell press. Simply maintaining position with one dumbbell demands so much from the core and glutes that it limits how much weight you can use , making it a poor choice if the goal is building strength or hypertrophy.

Using both dumbbells simultaneously creates more stability, allowing for significantly heavier loading and better muscle recruitment.

Unilateral training as it relates to the bilateral deficit is only possible when the unilateral exercise in question can maintain high, or nearly as high stability. Because if stability is severely punished, then the load will be low, and the contraction quality will be diminished compared to simply doing the exercise bilaterally.

This article isn’t a case for overhauling every program to be unilateral-only. It’s a reminder that strategic use of unilateral training can strengthen the program as a whole.

Below is an example of a cable lateral raise performed unilaterally, with a high level of stability due to holding onto a solid frame. The benefit to the cable variation to this lift is that tension remains high in the shortened AND lengthened position. 

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Point 3) Unilateral exercises help fix imbalances and build symmetrical strength

Another key advantage of unilateral training is its ability to detect and correct strength imbalances between limbs.

If applied properly, it can not only reveal differences that bilateral exercises often hide, but also directly help reduce or eliminate them over time. If the majority of the programs you build are bilateral in nature, how will you know whether both sides are working equally?

For the most part, you won’t. And over time, that hidden asymmetry can become worse.

With exercises like the bench press or squat, you might notice postural shifts that favor the stronger side, a clear sign of left-to-right weakness. But if you continue to push these movements without addressing the imbalance, the issue will only be exacerbated.

With other lifts, like machine-based exercises and many barbell-based movements, asymmetries may be more difficult to spot, meaning they can grow silently without obvious warning signs.

Coaching Tip:
When you see performance differences between sides, don’t just blast the weaker side with extra volume. Start by matching the stronger side’s reps, then gradually build the weaker side’s capacity with smart loading and rep schemes.

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If we think critically about which unilateral exercises benefit most from improved neural drive, we often find it’s the ones that maintain high levels of stability.

For rowing movements, having some form of external support, like a chest pad, a bench, or holding onto a sturdy machine, can help add that stability.

For example, a seated chest-supported row performed unilaterally would likely allow your client to express greater strength potential than a unilateral cable row.

The reason is simple: In a cable row, the lifter must stabilize their own body position or risk rotating toward the weight stack, which limits how much force they can focus into the row itself. 

Then again, if you’re training an athlete, building anti-rotation strength into your exercises might be a feature, not a bug.

If you want to learn more about machine-based exercises, take a look at this article!

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In training, there are rarely hard rules.
There are only mental frameworks you can use to make informed decisions.

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Point 4) Unilateral work builds real-world strength through better control and transfer

Listen, I know we often tout building muscle and building strength, and those are definitely two important goals that your clients are likely asking for.

But let’s take a moment to recognize that we don’t live our lives inside a gym performing perfect exercises.
At a certain point, we leave that controlled environment (shocking, I know) and move through the real world.

And when we do, the movements our bodies are exposed to are wildly unpredictable and seldom performed in an organized, thoughtful manner.

And that’s completely fine – in fact, normal.
If you train too stiffly, you’ll carry that stiffness into real life.

The smarter approach, even if your primary goal is muscle-building, is to create a body that can rotate, stabilize, and move fluidly, not just brace and lift heavy in a straight line.

When selecting unilateral exercises for your clients, it’s wise to choose variations that place the body in those exact real-world situations.
Think of a farmer’s carry with one arm overhead and a heavier load in the opposite hand.
Think of cable woodchops, single-leg RDLs, bounds, hops, side-to-sides, even sprints.

A sad state of affairs is a body that’s muscular but lacks any real athletic ability.

As a coach, it’s your job to build your clients from the ground up, from zero to hero.

They might come to you asking to build muscle.
Your job is to surprise them by delivering so much more.

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Conclusion

At first glance, unilateral training might seem like an optional add-on,  something you sprinkle into a program here and there for variation’s sake.
But as you’ve seen, when applied with intent, unilateral work can tap into new levels of strength, hypertrophy, control, and real-world resilience.

Remember, this article isn’t about demonstrating that unilateral exercises are superior, that would be missing the point.

It’s about recognizing when to use unilateral exercises to cover the gaps that bilateral exercises miss, and building stronger, more capable bodies that aren’t just strong in the gym, but built to move well in real life.