“Use exercise X to improve glute activation.” This phrase, or some variation of it, is something I hear often. It’s normally in the context of changing a motor pattern. But if that’s the case, the claim contains some implicit assumptions.
In almost every instance, those assumptions will be wrong and the “solution” perpetuates the problem it intends to solve. We’ll get to those assumptions and why they’re probably wrong. But to understand them, we need to take a step back and look at muscle activation and the stages of motor learning.
When someone talks about changing or improving muscle activation, what could they mean? Despite the terminology used, muscle activation is not about muscle. It’s about the nervous system. It’s the nervous system that controls if, when and how muscles contract. The muscle simply responds to signals from the nervous system. Those signals control several, usually subconscious (autonomous), effects.
The first effect is the most obvious one, muscle contraction and relaxation. The second effect is the strength of muscle contraction, which can be modified to determine the effect of contraction (isometric, eccentric, concentric). The third effect is the ratio of one muscle’s contraction relative to another, eg. increasing hamstring contraction relative to quadriceps contraction. The fourth effect is the order of contraction, eg. contracting the glutes before the hamstrings.
Stages of Motor Learning
The process of motor learning is defined by three stages: the cognitive phase, the semi-autonomous stage (aka the associative stage) and the autonomous stage.
The cognitive stage requires deliberate effort (mental or otherwise) to coordinate a movement. Think about learning to tie your shoes for the first time. You need to be shown what to do, how to hold the lace, how to move your fingers and hands to manipulate the shoelace and tie a bow.
To facilitate this stage of learning, cognitive load must be minimised so that focus can be maintained. You don’t demonstrate the entire task, sit back and say “now you try.” Instead, you break the task into manageable chunks and have them follow you through the process. As competency increases, smaller chunks are combined into slightly larger, more complex chunks.
After a while you’ll progress to the semi-autonomous stage. Cognitive effort is still required, but you’re getting the hang of it. Aspects of the task are becoming automatic. You don’t need to think about how to hold the shoelace, you just focus on tying the bow. Expect to spend some time in this stage and to make mistakes. But as time goes on, you’ll need to think less and less about the process itself.
Eventually, you don’t need to think about how to hold the shoelace or how the bow is tied. You just think “tie your shoelaces” and the process works on autopilot. Now you’re in the autonomous stage.
Methods for Change
The above example outlines the three stages of motor-learning, but it’s a simpler example than the claim we’re dealing with. When we’re tying our shoes, we don’t think “contract flexor digitorum profundus” to hold the shoelace, we just manipulate our fingers to mirror the person teaching us. But the claim “use exercise X to improve glute activation,” or some variation of it, is talking about that deeper level of coordination. It aims to change how the nervous system controls muscles to create movement.
There’s three methods (that I’m aware of) to pursue such change:
- electrical stimulation,
- an exercise that forces the desired motor skill, and
- learning to contract the target muscle with little or no participation from others.
The first method uses electrical stimulation to forcibly contract muscle via a Compex unit or something similar. They’re outstanding bits of kit, but they’re not an entry-level solution. The main obstacle is price. They’re very expensive. If you want a wireless model, they’re even more expensive. A lesser obstacle is electrode placement. You need knowledge of anatomy and the capacity to find it. Otherwise the electrodes will do nothing or you’ll target the wrong muscle.
The second method is far more accessible, but there are likely few exercises it applies to. Tasks that force a specific pattern of muscle activation are likely rare. The reason for this is redundancy. More often than not, movement is achieved by several muscles working together. If one muscle goes down due to injury or fatigue, others are available to pick up the slack. But that’s not to say such exercises don’t exist. The curl up can’t be completed without rectus abdominis and the side bridge can’t be completed without the obliques. However, forcing inclusion of a muscle is a far cry from forcing a specific order or ratio of contraction. Exercises that do the latter are likely rarer still, if any exist at all.
The third method is more accessible and less expensive, but it’s not quick or easy and cognitive load must be carefully managed. It begins with the tedious process of learning to deliberately contract a muscle with little or no participation from others (targeted contraction). It’s not unrealistic for this to consist of lying on the ground, palpating the target muscle and practicing its contraction. Once you can achieve targeted contraction, that skill is used to force an order of contraction and/or change the ratio of contraction. But initial progress is slow and incremental. Exercise complexity is restricted to your ability to maintain targeted contraction.
When someone states that “doing exercise X will improve activation of Y,” they’re making one of the following assumptions:
- the user is in the cognitive or semi-autonomous stage of motor learning and the prescribed exercise can only be performed with the desired motor skill, or
- the user is in the autonomous stage of motor learning.
If the user is in the cognitive or semi-autonomous stage of motor learning, the prescribed exercise must force the desired motor skill to be effective. But as mentioned earlier, such exercises are likely rare. This doesn’t mean the claimant is wrong, but it does mean you wouldn’t expect to see such claims often. However, anyone who watches or follows fitness personalities on YouTube/social media can attest to the contrary. Such claims are myriad.
If the prescribed exercise can be performed without the desired motor skill, there’s only one instance where it can be effective. When the user is already in the autonomous stage of motor learning. But at that point, they’ve already got the skill and the prescription is pointless.
Perpetuating the Problem
Motor skills are ingrained via repetition. The central nervous system doesn’t care what skill you intend to develop, it simply reinforces what you expose it to.
Let’s say a coach wants to improve ‘activation’ of their client’s glute medius. Specifically, they want to increase participation from that muscle (change the ratio of contraction) during hip abduction. They prescribe the banded side-walk to achieve that goal. Electrical stimulation is not being used and the client is not capable of targeted contraction.
For the coach’s solution to be effective, the banded side-walk must force the ratio of contraction they’re after. But this is not the case. Hip abduction can be achieved with multiple motor patterns due to redundancy. Glute maximus, glute medius, glute minimus, piriformis and the tensor fascia latae can all contribute to hip abduction. And there is more than one ratio of contraction for this group of muscles.
Since the banded side-walk can be performed with multiple motor patterns, it’s likely that the client’s nervous system will use the one it knows already. As a consequence of repetition, the existing motor pattern (the one they’re trying to change) will become more ingrained. The coach’s poor decision perpetuates the problem it meant to solve and the client has been moved further away from their goal.
A better course of action would be to use one of the other methods for changing motor patterns: electrical stimulation or targeted contraction.
Albeit expensive, electrical stimulation would have been quick and effective. Targeted contraction would have been slow and tedious, necessitating regression to far simpler exercises. But it would have provided the client with a useful skill to carry with them.
The idea that “doing exercise X will improve activation of Y,” is undeniably appealing. It seems a quick and simple fix. But although it might work some of the time, it’s unlikely to work most of the time.
When we look a little deeper and examine the assumptions behind the claim, its appeal is often a facade. And the facade of a solution is no solution at all. Worse still, it reinforces the problem it’s meant to solve.
~ The Critical Coach
P.S. If you enjoyed this, please share it with someone else.