Most people have more muscle capacity available than they’re actually using in any given movement.
That surprises people. If you can squat 200 pounds, you’re using everything you’ve got, right?
Not necessarily. During maximal effort, trained individuals can voluntarily activate 80-95% of their motor units (Herbert & Gandevia, 1999). But in everyday movements, most people recruit well below their maximum capacity. The gap between what you use habitually and what you could use with better coordination is where the real opportunity lives. And understanding why changes everything about how you think about strength.
What Recruitment Actually Means
Every muscle in your body is made up of motor units. A motor unit is a nerve cell plus all the muscle fibers it controls. When your brain sends a signal to move, it doesn’t activate the entire muscle at once. It recruits motor units selectively, calling in just enough to get the job done.
This is elegant engineering. You don’t need all your bicep to lift a coffee cup. Your nervous system recruits a small percentage of the available motor units, and that’s sufficient. Pick up a heavy suitcase, and more motor units get called to work. The system scales.
The problem is that most people’s scaling is inefficient. Their nervous system has learned to rely on certain motor units heavily while leaving others essentially dormant. Not because those dormant units are damaged or weak. They just haven’t been asked to participate in a long time.
This is like running a company where a small fraction of the employees do the vast majority of the work while the rest sit at their desks doing nothing. The company functions. But the overworked crew is exhausted, burnt out, and making mistakes. Meanwhile, perfectly capable workers sit idle.
Your body does the same thing. Certain muscles, certain portions of muscles, carry a disproportionate load. They fatigue faster. They get tight. They develop trigger points. They complain. And the solution the fitness industry typically offers is to make those overworked muscles stronger.
That’s like giving the overworked employees a raise and telling them to work harder.
Why Your Muscles Don’t Recruit Fully
There are several reasons why recruitment can be poor, and understanding them matters.
Inhibition from pain or injury. After an injury, your nervous system inhibits certain muscles around the injured area to protect it. This is smart in the short term. But the inhibition often persists long after the tissue has healed. Your brain got the memo to shut that muscle down and never got the memo that it’s safe to turn it back on.
I see this constantly. A client had knee surgery five years ago. The quad on that side still doesn’t fire as well as the other side. Not because the muscle is weak. Because the nervous system is still being cautious.
Habitual disuse. If you sit at a desk eight hours a day, your glutes are in a lengthened, passive position for most of your waking life. The nervous system adapts. It stops asking the glutes to do much because they haven’t been needed. Then you go to the gym and try to squat, and those glutes are slow to respond. Your back and quads pick up the slack.
Postural compensation. When your body is organized around a compensation pattern, certain muscles are held in positions where they can’t recruit effectively. A muscle that’s chronically shortened or lengthened beyond its optimal range has a harder time generating force. The nervous system routes around it.
Poor proprioception. Proprioception is your body’s sense of where it is in space. If you can’t feel a muscle, you can’t recruit it well. Many people have large blind spots in their body map. They literally can’t sense their mid-back, or their deep hip rotators, or their serratus anterior. These muscles exist and are perfectly healthy, but the neural connection is dim.
The Deadlift Test
Let me make this concrete.
Take a conventional deadlift. It’s one of the most effective full-body exercises there is. When performed well, it loads the posterior chain beautifully: hamstrings, glutes, spinal erectors, lats, grip.
Now watch ten different people deadlift. You’ll see ten different recruitment strategies.
Person one: the glutes fire hard at lockout, the hamstrings handle the bottom portion, the spine stays neutral. This person is using the right muscles for the right portions of the lift. Their recruitment is good.
Person two: the glutes barely participate. The hamstrings and low back do everything. The lift looks fine. The weight goes up. But the lumbar spine is handling load that the glutes should be managing. This person has a recruitment problem.
Person three: one glute fires and the other doesn’t. The lift looks slightly rotated. One side of the low back is working harder than the other. This person has an asymmetrical recruitment problem.
All three people might deadlift the same weight. Their “strength” looks identical on paper. But person two is heading for low back problems, and person three is heading for SI joint issues. Not because the exercise is dangerous. Because their recruitment strategy is loading certain tissues beyond what they should be handling.
This is why more reps won’t fix you. If you deadlift with poor recruitment, more deadlifts just reinforce the poor recruitment. You get stronger at the dysfunctional pattern.
How Recruitment Improves
This is where it gets interesting. Improving recruitment doesn’t require heavier weights, more reps, or longer sessions. It requires better neural signaling, and that’s a completely different kind of training.
Here’s what improving recruitment looks like in practice.
Step one: awareness. You have to feel the muscle before you can recruit it. If someone can’t sense their left glute, no amount of “squeeze your glutes” cueing is going to help. We need to wake up the proprioceptive connection first.
This might involve hands-on work. Tactile input is one of the fastest ways to bring a muscle back into awareness. I might place my hand on a client’s glute and ask them to gently press into my hand. The touch gives the nervous system something to aim for.
It might involve structural integration work, releasing fascial restrictions that are physically preventing the muscle from moving through its full range. If the tissue is adhered or restricted, the brain won’t try to recruit it. Free the tissue, and the brain suddenly has access to something it had written off.
Step two: isolation in a low-demand context. Before we ask a muscle to participate in a complex movement, we ask it to do something simple. A glute bridge with specific attention to feeling the glute work. Not a hard bridge. Not a heavy bridge. A slow, deliberate bridge where the only goal is to feel the glute turn on.
This is profoundly different from the gym version of a glute bridge, where the goal is usually to fatigue the glute with high reps or heavy load. We’re not after fatigue. We’re after connection.
Step three: integration into patterns. Once the muscle can fire in isolation, we teach it to participate in a more complex movement. The glute that just woke up in a bridge now needs to learn how to work during a squat, a lunge, a walk. This is where movement education really shines. We’re not just strengthening a muscle. We’re teaching it to play nicely with all the other muscles in a coordinated pattern.
Step four: loading. Only now, after the muscle can recruit well in the context of a full-body pattern, do we add load. And when we do, something remarkable happens. The client is instantly stronger. Not because they built new muscle. Because they’re using more of what they already have.
The Math of Recruitment
Let’s think about this practically.
Say you can squat 150 pounds. If significant portions of your available musculature are essentially offline, that means your tissues, at better recruitment, could handle substantially more.
You’re not going to achieve maximal recruitment of every motor unit. That’s not realistic outside of a life-or-death adrenaline surge. But meaningfully improving your recruitment efficiency? That’s achievable with good movement education. And the practical result is significant.
You don’t just get stronger. You get more evenly loaded. The tissues that were doing 90% of the work now share that load with tissues that have come online. Your overworked low back suddenly has glutes helping. Your cranky shoulder has a serratus anterior and lower trap sharing the burden.
This is why clients often tell me their pain decreased and their strength increased at the same time. Those aren’t separate outcomes. They’re the same outcome. Better recruitment means better load distribution, which means less overuse on any single structure, which means less pain, AND more total force production.
Why the Gym Doesn’t Automatically Fix This
I want to be fair here. Good trainers absolutely think about recruitment. Cueing is a real skill, and the best personal trainers are constantly working on helping clients activate the right muscles.
But there are limits to what cueing can accomplish when the underlying conditions don’t support good recruitment.
If a muscle is fascially restricted, cueing won’t override that restriction. The tissue needs to be freed first.
If a nervous system has been inhibiting a muscle for years, verbal cues may not be enough to override the inhibition. You might need hands-on input, specific positioning, and patient repetition to re-establish the neural pathway.
If the body is organized around a compensation pattern that puts a muscle in a mechanically disadvantageous position, that muscle won’t recruit well no matter how loudly the trainer cues it. The pattern needs to change first, then the recruitment follows.
This is the space movement education occupies. It addresses the conditions that make recruitment possible. It clears the restrictions, wakes up the proprioception, changes the patterns, and then lets the nervous system do what it’s actually very good at: organizing efficient, well-distributed effort.
Recruitment and Aging
This topic becomes especially important as we age. One of the key changes that happens with aging is a decline in motor unit recruitment efficiency. The nervous system gets slower at calling motor units to action, and slower at ramping up force production.
This is partly why older adults lose strength faster than they lose muscle mass. The tissue is still there, but the neural drive to use it diminishes. It’s also why training for adults over 50 should emphasize quality of recruitment, not just quantity of load.
Heavy lifting is still important. The research is clear. But if you’re loading a body with poor recruitment, you’re getting diminished returns and increased risk. Fix the recruitment first, and the loading becomes both safer and more effective.
What You Can Do Right Now
You probably can’t assess your own recruitment patterns in detail. That requires an outside eye and some hands-on assessment. But you can start paying attention to a few things.
When you squat, can you feel your glutes working? Not just at lockout, but through the whole movement. If you can’t feel them, they’re probably under-recruited.
When you push something overhead, do you feel your lats and lower traps engaging? Or is all the effort in your upper traps and shoulders?
When you walk, can you feel your feet pushing off the ground, or are you just picking your legs up and putting them down?
These questions aren’t exercises. They’re awareness practices. And awareness is the first step toward better recruitment.
In the next post, I’m going to talk about a principle that ties directly into this: the idea that pattern must come before load. It’s a concept from the rehabilitation world that the fitness world hasn’t fully absorbed yet, and it changes how you should think about programming.
If you want to find out what your body’s recruitment picture looks like, come in for a session. I can show you what’s working, what’s checked out, and what it takes to get more of your body in the game. It’s one of the most useful hours you can spend on your physical health.