1/4 Hour Neuro #34: "How to Address Muscle Imbalances?"

Welcome to the Neuro Quarter Hour

Welcome to the Neuro Quarter Hour, the meeting dedicated to bringing a neuroscientific perspective to training issues on the field. Today's topic, "How to Address a Muscle Imbalance?", stemmed from an Instagram post that sparked numerous reactions. Did you know that doing two extra repetitions won't necessarily solve a muscle imbalance?

This question leads us to explore the origins of these imbalances and, most importantly, how to correct them. It is interesting to note that bodily balance is closely linked to the balance of the central nervous system, including the vestibular system and the cerebellum. Therefore, before attempting to address a deficit, it is crucial to ensure that these systems are functioning properly. As is often said, everything is about balance, and even a slight imbalance can have repercussions far beyond mere muscle strength, potentially causing anxiety.

The Impact of Neurological Imbalances on Muscle Symmetry

A muscle imbalance is not always the result of a lack of localized training. It can originate from dysfunctions within the nervous system. For instance, a person performing "double unders" with one arm extended more than the other may have a potential imbalance that is not only muscular but also static and dynamic, leading to compensation on one side more than the other and an increased risk of imbalance.

It is therefore essential to check "sensory inputs". The foot, for instance, plays a fundamental role. A foot that turns inward already creates an imbalance, as one side will be less engaged than the other. Similarly, a convergence deficiency can lead to an imbalance in muscle recruitment from one side of the body compared to the other, as the brain does not react symmetrically. These neurological deficits directly impact the muscles' ability to contract evenly.

Beyond Reps: When Sensory Inputs Dictate Strength

How many people say, "I push harder on the right than the left" during a bench press? Many believe that it's normal, as the body is not perfectly symmetrical. However, this is not a foregone conclusion. When sensory inputs are not properly calibrated, a muscular asymmetry emerges. This is often observed during the bench press, where the bar may shift to one side. These compensations, whether conscious or unconscious, are signs that something is wrong.

What causes these asymmetries? It could be related to the eye, the jaw, or a sensory issue at the hand level. It is essential to identify the underlying cause through an assessment and targeted tests. For example, working on eye function or the vestibular system can immediately improve symmetry. If an asymmetrical tonic reflex is involved, specific exercises can also provide quick correction. Any compensation reveals an underlying imbalance that must be addressed.

Neuromuscular Reintegration for Sustainable Progress

Movement occurs in three stages: information gathering, interpretation, and decision-making, followed by movement execution. Muscle imbalances manifest during the third stage. Therefore, it is crucial to examine the preceding stages, particularly the quality of the information and its interpretation.

The Importance of the Brainstem and Decussation

A key area within the brainstem, where decussation (crossing of nerve pathways) occurs, plays a fundamental role. The left brain controls the right side of the body and vice versa. If this part of the brainstem is immature, prioritizing work on a weaker side can be counterproductive. Sometimes, to enhance the right side, it may be necessary to work on the left side with isometric exercises or other neurocognitive approaches. The goal is for the brain to command the muscles to recreate harmony and balance, not by structurally working a muscle, but by optimizing nerve command.

Immediate Reintegration: Neuro Exercise + Movement

Once the imbalance is identified and the neurological correction is made, immediate reintegration is essential. This involves performing a neurological exercise followed by a related movement, but with neuro stimulation. For example, after a correction, one might perform isometric work on the bench press to "match" the information at the brain level. Then, movement execution should be controlled with precise tempos and careful monitoring to ensure maximum information integration.

Our body is not naturally bilateral; it requires an optimized system for bilateral movements such as squats or bench presses. Training should not only focus on metabolic or structural impact. Different contraction regimes (isometric, concentric, eccentric) activate the brain differently and can be used to create new neural connections, especially when safety is paramount.

Isometric exercises, for example, are a safe form that shows the brain that movement is possible and safe. When the brain perceives a movement as "safe," it opens the door to new capabilities and ranges. To delve deeper into max intensity in training and its link to balance, we invite you to listen to the podcast with Julien Pinot, who explores this fascinating subject further.