Why Single-Arm and Single-Leg Training is Better for Athletes

Unilateral training will improve your athletic performance far more efficiently than traditional bilateral compound movements.

Unilateral Exercises Are More Realistic For Athletes

To boost your athletic or sporting performance, you need to work with the right tools. When it comes to athletic movement, a couple of key patterns stand out:

  • Athletic movements are made up of reciprocal motion to provide power and speed—the limbs work in opposite action to each other.
  • Sports are played on one leg—you are in motion most of the time.

These observations make it clear that the importance of single-leg strength, in particular, cannot be overstated. Despite this, many sports training programs are built around heavy compound multi-lateral exercises, like Back Squats, Deadlifts, Cleans and Snatches. The problem with these movements as they relate to sports performance is that the body isn't used to pushing off the ground with two legs at the same time. For athletic performance, training on one leg at a time far more closely mimics the things you do on the field.

Unilateral Training Works More Muscles

Though it may seem logical that an athlete who is stronger in bilateral movements like the Bench Press will also be stronger on unilateral moves, a 2007 study showed that this is not the case. Stuart McGill and his colleagues took a group of athletes with high Bench Press numbers and compared their performance in the standing unilateral Cable Press with a second group who had average Bench Press numbers. They found no correlation between Bench Press strength and unilateral strength.

The reason there is no direct correlation between bilateral compound movement strength and unilateral strength is that several more muscles are involved in a unilateral move than the sheer power of the prime movers in a matching compound movement. For example, when you do a standard bilateral Squat, you work your quads, hamstrings, glutes and hip flexors. But when you go to a single-leg stance, you also get the adductors involved, along with the gluteus medius, quadratus lumborum and a number of smaller muscles that must engage to keep your body from rotating and twisting sideways—as well as to keep you performing the exercise. All of the additional muscles that come into play are called the lateral subsystem.

It's interesting to note that you can perform the Squat on one leg with more weight than you can when combining the weight on a bilateral Squat. In other words, if you can squat 100 pounds on two legs, you should be able to squat more than more than 50 pounds on each leg doing unilateral Squats. That's because of what is called the bilateral deficit.

Our bodies are not wired for both limbs to push together. As a result, you won't be able to put up the same kind of weight as you can on a single leg. Also, as we've seen, more muscles are doing the work on a single-limb move.

Unilateral Training Trains the Core

A great benefit of unilateral exercises is that they also train the core. When you do a Single-Leg Squat, you give your core a great workout, because it must work to support your body in an athletic position. When one foot is unsupported, the muscles in your core engage to balance and stabilize that limb.

Single-leg training also improves control of your hips and lower back, which greatly assists in maintaining neutral posture, enhancing your ability to cut in sports like football and basketball without losing control of your core and upper body.

Single-arm training forces you to link your hips to your ribs, allowing you to be strong from top to bottom.

Unilateral Training is Safer

Unilateral training is great for injury prevention. Single-leg training allows for better control of knee collapse, which is a common problem during the conventional Barbell Squat and is associated with ACL injury. When training on one leg, the lower back and the hips must be held in a better position, so you're less likely to suffer a spinal disc injury.

Single-leg training allows you to work your dominant and non-dominant sides equally. This can prevent injuries that result from favoring one side during the bilateral version of the move. With the bilateral version, a takeover by the dominant side tends to increase the strength differential between the two sides, opening the gap and putting you at greater risk of an injury on the field. When training on one leg, however, you work your dominant and non-dominant sides equally.


If you are training for sports performance, unilateral training will improve your on-field or on-court performance far more efficiently than traditional bilateral compound movements. It works more muscles, balances your strength, hits your core and spine, improves your balance and enhances your speed and agility.

Isn't it time you reap the benefits of unilateral training for yourself?

Key Unilateral Moves


Unilateral Squat

  • Stand with your legs shoulder-width apart. With two hands, hold a dumbbell against your upper chest, just under your chin. Bend your dominant knee about 90 degrees so your foot is halfway between the floor and your butt.
  • Bend your other knee and squat down until that thigh is parallel to the floor. Pause, then return to the starting position.
  • Keep your torso as upright as possible throughout. Finish the set, then repeat with your other leg.

Unilateral Bench Press

  • Lie on a flat bench holding one dumbbell over your mid-chest with an overhand grip and straight arm.
  • Pinch your shoulder blades back, bend your elbows and slowly lower the dumbbell until it is right next to your armpit.
  • While you press the dumbbell with one arm, hold on to the side of the bench with your opposite hand.
  • Switch sides and do the same number of reps, or address a strength imbalance by doing an extra set or two on your weaker side.

Bulgarian Split-Squat

  • Rest a barbell on your traps and stand with the instep of one foot on a bench or sturdy stool positioned behind you.
  • Do a Split Squat, descending until the top of your front thigh is parallel to the floor. Pause, then push back up to the starting position.


Santana, J.C., Vera-Garcia F.F., McGill, S.M."A Kinetic and Electromyographic Comparison of the Standing Cable Press and Bench Press," J Strength Cond Res. 2007 Nov;21:4 1271-7

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