1/4 Hour Neuro #59: "Using and Interpreting Strength Deficits"

Introduction

Hello everyone and welcome to the neuro quarter-hour! This week, we are tackling a common question: the use and interpretation of strength deficits. A listener, after completing a full cycle to address their strength deficits in flexion and extension, still faced imperfect results. This podcast explores avenues to understand and correct these imbalances, highlighting the importance of a neurocentric approach.

The fundamental idea is that the chain is only as strong as its weakest link. In physical preparation, particularly for structural balance, basic tests can identify weaker muscle groups, allowing for the establishment of a remediation program. However, the classical approach does not always take into account all facets of these deficits.

Understanding Strength Deficits and Structural Balance

Strength deficits in weight training are often evaluated through tests after at least two years of experience. The goal is to detect imbalances between different muscle groups, particularly extensors and flexors. In neuroscience, extensors are associated with abductors and external rotators, while flexors are linked to adductors and internal rotation. These tests help identify weaker movements or patterns, which can then be targeted by remediation cycles, often lasting twelve weeks, to restore ratios and structural balance.

The Neurocentric Approach: Beyond Muscle

The neurocentric approach goes far beyond mere muscle strength. It focuses on the root causes of deficits, which may be related to issues at the brainstem level rather than solely at the corticospinal tract. A lack of reflex stability, for example, can impact the activation of flexors or extensors. This is why observing functional movements such as walking or squatting can reveal valuable insights into these imbalances.

Reflex Stability and Motor Patterns

It is crucial to understand that deficits may manifest differently between the left and right sides of the body, or between the upper and lower body. A neuro-oriented training program must target these failing motor patterns to rebalance brain function. The goal is not just to train the muscle, but to optimize reflex stability, which represents a significant portion of cortical weight, much more than voluntary movements.

Flexion, Extension, and Rotation: A Holistic View

Interpreting strength deficits must incorporate a holistic view of flexion and extension chains, as well as internal and external rotations. The movements we perform always involve a combination of flexion and extension, and it is fundamental to consider information from the brainstem and the entire nervous system. Before solely focusing on muscle structural balance, it is wise to rebalance the neuronal foundations.

Complementarity of Training Methods

Approaches like "structural balance" are very relevant for assessing the effector muscles and voluntary movement. However, it is important to complement them with a neurocentric approach focused on reflex stabilization. Specific areas of the brainstem can be targeted through small exercises during warm-ups or between sets. These "addons" optimize what you are already doing, giving you better access to your potential.

Integrating Neuroplasticity into Your Program

Methodologies like Rehab-U or StrongFirst are excellent, but it is essential to contextualize them. Rehab-U, focused on mobilization, activation, and integration, is very effective, but one must know when and why to use it. StrongFirst, on the other hand, is an output-based approach (the result of the movement). We place more emphasis on input (sensory inputs) and utilize output as a means of before/after comparison. The aim is to recreate muscle tension and brain-muscle connections by promoting tension in the chains, but especially after addressing the root issues causing these imbalances, often found at the brainstem level. First, we must rebuild the "information highway" for movement to flow smoothly.

All these approaches are interesting and complementary. Remember that before being an athlete, you are a human being, and our functioning is intrinsically linked to our nervous system. It is therefore essential to return to these fundamental steps.