Bilateral vs. Unilateral Training
In the words of powerlifter and chiropractor Dr. Shallow, "Why squat on two legs when you can't stand on one?” On the importance of unilateral training, Dr. Shallow notes that, “Humans are bipedal creatures whose gait cycle is unilateral; training bilaterally isn't necessarily functional as it pertains to the joints. However, the overall nervous stimulus of training with heavy loads bilaterally can be beneficial for performance. In order to maximize the safety of the joints, one needs to have stability. If an athlete does not have unilateral stability, we shouldn't expect them to display it bilaterally under heavy loads. Thus, the chance of crummy form and risk of injury increases.”
Bilateral and unilateral training are exactly what they sound like. Bilateral means training both sides of the body, while unilateral means training one side of the body. The two complement each other, but the proper ratio for your goals and sport has to be found.
Both bilateral and unilateral training should be utilized in balanced doses. Most athletes get a fair amount of bilateral training in. Think the big compound lifts squats, deadlifts, bench press, snatches, and cleans. These are incredibly useful for maintaining fitness and building strength, but unilateral training has greater functional carry over to sports and daily life, as most activities we perform are unilateral in nature.
Benefits of Unilateral Training
Makes you stronger in bilateral movements
Unilateral and bilateral exercises work in tandem. Doing rear foot elevated split squats will make you stronger in your squat and deadlift and vice versa. Plus, intermixing unilateral and bilateral work automatically creates “constantly varied” workouts, a training component we always strive for.
Decreases injury risk and optimizes sports performance
Most sports are performed on one leg. From a sprinter on the track to a soccer player making a cut to defend their opponent, “one leg will have to support and produce strength up to twice the athlete's body weight. If the leg, from the ankle to the hip, cannot absorb and produce this kind of force, an injury is inevitable” (Technogym).
Stability and balance
Not only are the joint stabilizer muscles required to fire more in a unilateral movement, but greater core stability is also required as your body tries to maintain balance on one leg or using one arm.
A concept known as cross education says that training one limb can cause strength gains in the other, unused limb. This is beneficial for those who have an injury on one side of the body, like a left knee or right shoulder. Studies have found an 11.9% increase in contralateral (opposite side) strength after performing unilateral exercises.
Unilateral Exercises to Try Today
Single Leg RDL
Rear Foot Elevated Split Squats (aka Bulgarian Split Squat)
Single leg step ups (forward or lateral)
Single arm row
Single arm bench press
Single arm shoulder press
This is not to say that bilateral movements should be thrown out the window and replaced with all unilateral movements. Bilateral exercises 100% have a place in development of strength and power, but including unilateral exercises can make the difference in terms of injury, imbalances, and overall strength and stability for an athlete. The trick is to figure out the proper ratio of the unilateral vs. bilateral exercises in your training. Looking to optimize your training by incorporating some unilateral work? Looking to rehab from an injury? Here at Prime, we incorporate unilateral movements in our prehab, rehab, and general fitness programs. Reach out to firstname.lastname@example.org today to set up an initial consultation!