How to maximize muscle recruitment?

By Pierre-Luc Dubé

Have you ever asked a customer where they felt a movement and for them to reply “I don’t know”?

It is important to understand that performing an exercise is not necessarily sufficient in order to stimulate a muscle group and cause an adaptation. As Christian Thibaudeau has already mentioned: “A muscle that is not felt is not stimulated. “Indeed, the human body will always adapt to demand in order to perform an exercise even if recruitment is not optimal. It therefore transfers the task to other muscle groups which are normally secondary to the task requested. That being said, it is important to identify what really prevents our clients from having optimal muscle recruitment.

Muscle recruitment is the brain’s ability to produce a nerve impulse to allow a muscle to contract. This ability can be altered by various factors such as an incorrect motor pattern. Perfect practice makes perfect. Thus, an individual who originally did not have the correct activation sequence may have integrated a faulty motor pattern by the repeated practice of a movement. Unfortunately, an altered motor pattern can be difficult to correct if it has been repeated many times.

There may be an asymmetry in the strength and / or endurance of certain muscle groups. The body, being a loose machine, will favor certain groups with which it is easier and economical to carry out a movement. It may also simply be that the nervous activation of one or more muscle groups is not strong enough to be able to cause them to contribute to the contraction. Take the bench press example. An individual may have a stronger triceps or better activation of it. Thus, during a pushing movement, it will contribute more and will be felt hastily. This asymmetry can be caused by several factors such as the nature of the sports practiced, an unbalanced training distribution, an injury, etc. There may be other reasons behind the difficulty in recruiting muscle, but these seem to be the ones that come up most often among my clientele.

Now that a few causes have been listed, here are some ways to address them. It is important to activate the main muscles, but also those working in synergy with them in order to more easily transmit the load to the desired muscle group. It must be understood that to activate the targeted muscles, it is not only a question of performing a few submaximal repetitions of the exercise per se.

I regularly use pre-fatigue on isolation exercises for muscle groups that are difficult to recruit in order to pre-activate them and promote better muscle sensation. However, it is important that this activation is not too long in order to avoid creating too much fatigue which would minimize the work of the muscles afterwards.

In addition, the fact of tiring and / or stretching the opposing muscle groups allows a better transfer of the load on the desired muscles by reducing the reflex effect of the opposing groups. For example, fatiguing the muscles of the posterior chain will allow the recruitment of a wider range of muscle fibers from the anterior chain.

On the other hand, the frequency at which a muscle is trained also facilitates its recruitment. The more often a muscle or motor pattern is exercised, the more easily the body will process the request. It is still important to remember that this principle only works if the practice is perfect, in order to avoid reinforcing an existing altered pattern. In addition, beyond facilitating muscle recruitment, regular work on a muscle group reduces the contraction of the antagonist muscle, which increases its effect.

In summary, regardless of the technique used, performing a movement is not enough to benefit from its full potential; feeling the targeted muscle groups contract is essential.

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