Four Reasons You Can’t Lunge as Much as You Can Squat and How to Incorporate Unilateral Exercises to Hurdle the Gap.

Written By Michael Campanella

The “unilateral deficit” describes the scenario where an individual’s strength in exercises that engage both limbs (bilateral exercises) doesn’t proportionately translate to exercises that work each limb independently (unilateral exercises).

The Gap Between Bilateral and Unilateral Exercise Strength

First, we all know those athletes who can squat and deadlift heavy weights but struggle with lighter weights in lunges, single-leg deadlifts, or split squats. Shouldn’t the strength from heavy squats and deadlifts carry over to unilateral exercises? The reality, however, is complex.

How Unilateral Neglect Drives the Strength Deficit Gap 

1. Neuromuscular Coordination: Unilateral exercises require coordination from a greater proportion of stabilizer and synergist muscles due to the independent movement of each limb. In contrast, bilateral exercises require less coordination, as the load is shared across both limbs, slightly minimizing the requirement of stabilizer muscles.
2. Muscle Weakness: Unilateral exercises recruit the stabilizer muscles to a greater degree when compared to bilateral exercises. Underdeveloped stabilizer muscles, neglected through a lack of unilateral exercises and/or a disproportionate emphasis on bilateral training, will not be able to perform as effectively when called to act in an isolated fashion.
3. Muscle Imbalance: Often, individuals unknowingly favor one side during bilateral exercises, or engage one side more than the other, leading to uneven development.
4. Core Engagement: Bilateral exercises require relatively less core engagement to maintain balance and posture. Weaker core muscles can therefore affect performance in unilateral movements.

Negative Outcomes of Unilateral Exercise Neglect

1. Increased Injury Risk: Muscle imbalances and poor stabilization can increase the risk of injuries, particularly under heavy loads or during dynamic movements.
2. Compromised Functional Strength: Real-world activities and sports often involve unilateral-based movement patterns. A unilateral deficit can therefore translate to poorer performance outside the gym.
3. Missing Hypertrophy Potential: There’s an argument to be made that skipping unilateral movements can lead to asymmetrical or incomplete hypertrophy development.
4. Slower Progress in Bilateral Movements: The neuromuscular challenge posed by unilateral exercises can enhance overall efficiency and power, thus bolstering bilateral movements. Focusing solely on bilateral training risks missing out on these neuromuscular benefits, potentially slowing progress.

How to Hurdle the Unilateral Deficit Gap

1. Incorporate Unilateral Exercises: Thank you, Captain Obvious!  But seriously, start by adding lunges, split squats, and single-leg deadlifts, into your routine. Begin with body weight or light loads until you can do 10-15 reps per side, and then begin to increase loads.
2. Focus on Form and Symmetry: Lift with more intent and think about form and symmetry in both unilateral and bilateral exercises. Use mirrors, video feedback, or a trainer’s guidance to identify and correct imbalances.
3. Strengthen Your Core: Adequate core strength and stability in unilateral exercises lies in being able to resist flexion, extension, and rotation. Exercises that bolster core and hip stability are pivotal. Incorporating movements like planks, loaded carries, and half-kneeling or tall-kneeling anti-rotation presses can enhance core and hip stability. 
4. Progress and Adapt: Gradually increase the intensity and complexity of your workouts, giving your body time to adapt. Concurrently, regularly evaluate your strength and performance across both unilateral and bilateral exercises, using these insights to fine-tune your training regimen and correct any imbalances.

In Conclusion, Hurdle the Gap For Balanced Strength!

The unilateral deficit is an often overlooked but important aspect of strength training that can slow progress and increase injury risk. Unlock new levels of strength and performance and pave the way for a more balanced physique by actively working to hurdle this gap.