One of the best things about fitness is that your options for training are nearly limitless. If you want to gain strength, put on some muscle, or just feel better overall, there are plenty of options on the plate. However, you might end up falling prey to paralysis by analysis if you don’t know which methods are effective for pursuing your goals.
Most good workout routines include a slew of bilateral movements such as barbell squats, deadlifts, presses, rows, or even snatches and cleans. That said, research suggests most athletes can benefit immensely from adding unilateral training — training with one side of the body at a time — into their current training routine. (1)
By not training unilaterally, the literature also indicates that you might be leaving gains in core stability, joint integrity, and strength on the table. (2) To make sure you’re getting the most out of your time in the gym, we’re going to lay out the benefits of unilateral training and discuss how to do it properly.
Benefits of Unilateral Training
Note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. When starting a new training regimen and/or diet, it is always a good idea to consult with a trusted medical professional. We are not a medical resource. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. They are not substitutes for consulting a qualified medical professional.
Muscular and movement imbalances can be systemically detrimental if not addressed. By solely performing bilateral lifts like squats and deadlifts, many imbalances may go unnoticed, often hidden by the body’s natural tendency to compensate.
Those compensation behaviors often lead to movement faults, muscle weaknesses, and potentially injuries or discomfort. Simply adding unilateral training into your assistance program can improve potentially harmful muscular and movement-based imbalances by showing you where you’re weak and where you’re strong.
For example, research suggests that single-arm shoulder pressing can lead to greater muscle activity and core stabilization in the trunk, meaning that you don’t need to wait until ab day to get your six-pack training in. (3)
Boost Sport Performance
Nearly all athletic movements are done unilaterally. Whether you’re on the track, court, or field, chances are you’re sliding, running, or catching with a staggered stance or one foot. To that end, both traditional sport and strength and power athletes can use unilateral training as part of their assistance work to bulletproof their bodies and practice how they play.
Decrease Injury Risk
Injuries often result from overuse, muscular imbalances, or poor movement. Unilateral training offers coaches and athletes the ability to isolate specific movements, muscles, and joints to increase symmetry of muscular development and movement.
By training unilaterally, athletes can better diversify their fitness, attack muscular weaknesses and imbalances, and close the asymmetry gaps that may go unnoticed if you’re only ever working with both limbs.
[Related: The Four Things You Can’t Learn From Your Coaching Certification]
Improve Muscular Stimulation
Unilateral training can promote greater muscular stimulation. Referred to as the “bilateral deficit,” research indicates that EMG activity and strength recordings were higher in unilateral limbs when relatively compared to bilateral movements.
The ability to isolate and train individual movements and muscles on an unilateral basis could help promote muscular development and growth. (4)
Speed Injury Recovery
Muscular injuries happen and, unfortunately, they might deter you from exercising regularly. After an injury, it’s important to rest but that doesn’t mean you should forego the gym altogether. Research suggests that it can take just two weeks to up to a third of your muscle strength. (5) Provided you have clearance from a doctor, unilateral exercises are a good way to retain as much of your gains as possible.
In fact, the science implies that unilateral training will not only strengthen the muscle being worked but also has positive effects of strength and muscle on the contralateral side. (6)
Develop Motor Skills
There are plenty of muscular and strength benefits of unilateral training, but not often talked about is the effect it has on the brain and motor skills. Studies suggest that motor engrams — memorized movement patterns stored in the motor area of the brain — may develop after performing unilateral movements. (7)
Your motor skill level affects nearly everything you do outside of the gym. Developing motor skills can improve reaction time, which is important when driving, and come into play when lifting a heavy object, such as a loaded barbell.
What is Unilateral Training?
Simply put, unilateral training is any form of movement that trains one limb at a time, rather than both arm or leg simultaneously. Common examples are split squats, single-arm pressing and rowing, single-leg Romanian deadlifts, and pistol squats.
Any exercise you perform with both arms or legs probably has a viable unilateral version. The versatility and ability to find a single-limb movement, whether you’re working with free weights or just your own body weight, make unilateral training easily applicable to your fitness routine.
Unilateral vs. Bilateral Training
Most athletes train strength, power, or their competition lifts using bilateral exercises. Unlike barbell squats or pulls, unilateral training offers a unique training stimulus to maximize performance, increase injury resilience, and even enhance your power output.
Over time, poor movement mechanics and compensation can lead to inefficient bar paths, overuse injury, and stalled progress. By addressing your weaknesses early — both technical and muscular — with unilateral training, you can better develop or maintain your muscle mass and strength.
Best Unilateral Exercises
There are plenty of unilateral exercises out there, so it might be hard to decide which ones to do. The truth is, whichever unilateral exercise you choose, as long as it’s done with proper form, will allow you to reap the benefits.
Single-Leg Romanian Deadlift
The deadlift is one of the best moves you can do in the gym, so it comes as no surprise that a single-leg Romanian deadlift is one of the best unilateral exercises you can do. Your balance will be challenged and improved, and you can also strengthen the muscles in the posterior chain.
Whether you want to deadlift more weight or just get a good hamstring pump, the single-leg Romanian deadlift should be a part of your program.
Single-Arm Bench Press
One of the purposes of the single-arm bench press is to improve stability in the shoulder and in the core. Challenging shoulder stability can help improve the standard bench press and may help reduce the risk of injuries. Your core also has to show up to keep you locked in place for the entire set.
You may not be able to push as heavy of a weight as you do in a bench press, but that’s okay since the purpose of the movement is more technical. Training both sides equally can prevent your stronger side from compensating for your weaker side, ultimately improving your barbell bench press.
Single-Arm Dumbbell Row
Pulling exercises are important for strength, posture, and injury prevention, and the bent-over row is notorious for building the back. The lats are responsible for supporting the spine and providing structural strength across the back and shoulders. Performing your rows unilaterally allows you to focus on strengthening each side of your back equally.
Bulgarian Split Squat
Single-legged squatting separates people in the gym. While the back or front squat is quite challenging on its own, sinking into a deep squat on one leg takes things up a notch.
Fortunately, the benefits are just as extreme. When split-squatting with one foot elevated behind you, you have to maintain stability from head to toe while challenging your leg strength and hip flexibility simultaneously.
While you may not think of the side plank as a unilateral movement at first, rest assured that it comes with all the benefits. Working your core isometrically is great for keeping your spine strong and abs hard as a rock, but turning things sideways provides even more bang for your buck.
The side plank forces the core musculature to stabilize the spine in the frontal plane. This mimics real-world movement, but is not often addressed by standard abdominal or barbell exercises. The side plank is a quick, easy, and effective way to get some unilateral work in — and you don’t need any equipment to do it.
Unilateral training deserves more praise. Although the barbell deserves the limelight when it comes to getting freakishly strong, single-arm or leg movements are unparalleled in their versatility.
By taking the time to address unilateral concerns, you can do more than just ensure you aren’t shifting sideways in your back squats. If you want to gain some new muscle and are bored of the barbell, get to work on one foot. If you consider yourself an athlete, unilateral training deserves a seat at the table.
- Carroll, T. J., Herbert, R. D., Munn, J., Lee, M., & Gandevia, S. C. (2006). Contralateral effects of unilateral strength training: evidence and possible mechanisms. Journal of applied physiology (Bethesda, Md. : 1985), 101(5), 1514–1522. https://doi.org/10.1152/japplphysiol.00531.2006
- Kuruganti, U., Murphy, T., & Pardy, T. (2011). Bilateral deficit phenomenon and the role of antagonist muscle activity during maximal isometric knee extensions in young, athletic men. European journal of applied physiology, 111(7), 1533–1539. https://doi.org/10.1007/s00421-010-1752-8
- Behm, D. G., Leonard, A. M., Young, W. B., Bonsey, W. A., & MacKinnon, S. N. (2005). Trunk muscle electromyographic activity with unstable and unilateral exercises. Journal of strength and conditioning research, 19(1), 193–201. https://doi.org/10.1519/1533-4287(2005)19<193:TMEAWU>2.0.CO;2
- Pinto, et al. (2012) Evaluation of bilateral deficit in isometric contractions of the knee extensors. Brazilian Journal of Kinanthropometry and Human Performance. 14(2). https://doi.org/10.1590/1980-0037.2012v14n2p202
- Andreas Vigelsoe, PhD et al. Six weeks’ aerobic retraining after two weeks’ immobilization restores leg lean mass and aerobic capacity but does not fully rehabilitate leg strenght in young and older men. Journal of Rehabilitation Medicine, June 2015 DOI: 10.2340/16501977-1961
- Cirer-Sastre, R., Beltrán-Garrido, J. V., & Corbi, F. (2017). Contralateral Effects After Unilateral Strength Training: A Meta-Analysis Comparing Training Loads. Journal of sports science & medicine, 16(2), 180–186.
- Hendy, A. M., & Lamon, S. (2017). The Cross-Education Phenomenon: Brain and Beyond. Frontiers in physiology, 8, 297. https://doi.org/10.3389/fphys.2017.00297
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