Motor Learning- Cementing Habits

Motor Learning- Cementing Habits 

Olympic swimmers have some good looking strokes and you might think it has to do with their muscles, heart and lungs. But what you are actually seeing is the finely tuned and well written brain programs they use to control their body during a race. Usually, we say great swimmers have great technique, but we are going to dive a little deeper into what scientists call Motor Patterns.

So what exactly is a Motor Pattern? It’s easier to explain with an example. Let’s say you want to take a step up one stair. You don’t actually think about it, it just happens. That is the Motor Pattern for “stepping up” taking control. The Motor Pattern in this case is controlling the muscles of your legs and torso to move in the proper sequence and use the proper force in order to make that step up.

Now this is a really simple Motor Pattern, but they can be as complex as playing Beethoven’s Moonlight Sonata 3rd Movement… or swimming butterfly. With practice and repetition of certain motions, the brain automatically starts writing out a program for a new Motor Pattern. This mechanism of creating new Motor Patterns is called Motor Learning.

We are going to go through both of these concepts, which can unbelievably complicated! But don’t worry, we will keep things simple-ish. After all, you want to have an awesome looking stroke, right? That means training your brain because there is no such thing as “muscle memory.”


Motor Patterns: Technique

These Motor Patterns are stored in the brain (and sometimes spinal cord) and the instructions are transmitted to the muscles by nerves. Just like we talked about in the Motor Unit chapter.

So if these Motor Patterns are embedded into our brain somewhere and send real electric signals through nerves to the muscles, then we should be able to see it right? Well, here it is…

Why in the world is this so complicated? Let’s take a look at our step up analogy again. What if the step was bigger than you expected? What if you were stepping on a ladder with sagging struts? What if you had high heels on? What if your eyes were closed? The problem with a Motor Pattern that is based on rigid rules and direct unchangeable commands is that you would need a program for every conceivable circumstance, which will slow your brain down and take too much space to store (like a computer with a full hard drive). Instead, the brain uses constant sensory feedback from your skin, joints, muscles and eyes to continuously adjust the Motor Pattern being executed to fit the needs of the motion.

Tangent: Back in olden times, computers ran on programs that were stored on something called a “drum.” Motor Patters were thought to be similar to how computers operated, and so describing this biological computer was known as Henry’s Memory Drum Theory.

That means information must go from the top down, the down up, and sideways. In a simplified diagram, it would look like this:

I know… it’s not that simple. Let’s take a look at these neural highways piece by piece. Motor commands involve sending a signal that starts at the motor cortex. The motor cortex is where the control of muscles happens. It is a conscious part of your brain, so whether you are trying to activate one single muscle (biceps for curls) or if you are activating a complex Motor Pattern (swimming butterfly), the message starts from the motor cortex which is located on the outer surface and middle of your brain, literally at the top.  The cortex is the wrinkly outer surface of the brain, named after “tree bark” in Latin.

Tangent: Powerful magnetic pulses can activate the motor cortex and cause involuntary muscle contractions. This is called Transcranial (across skull) Magnetic Stimulation. It is being researched as a way to help the brain heal itself.

If no Motor Pattern exists for the motion you are trying to do, the signal travels directly down the spinal cord and activates the Motor Unit neuron located in the spinal cord (review in our Motor Unit chapter). This neuron then activates all the muscle fibers it is connected to, anywhere from 10 to 1000 muscle cells, and produces motion.

This is a very conscious control of muscles. Think about when you tried to learn how to play a musical instrument for the first time. Every movement of your fingers had to be consciously controlled and told what to do.

Now let’s say you have been practicing this musical instrument for a while and have built up some Motor Patterns. The signal still starts in the motor cortex again, but this time the signal is going to take a detour into the basal ganglia. The basal ganglia are a group of neurons that act like processing centers (Basal = base, ganglia = group of neurons, so basal ganglia are groups of neurons in the base of the brain). They decide what and how to activate the Motor Pattern selected. Once the processing is complete, they signal the motor cortex again to activate the right motor unit nerves in the correct sequence and with the correct strength required to produce the motion that the Motor Pattern is trying to achieve.

Tangent: Destruction of different parts of the basal ganglia causes diseases like Parkinson’s and Huntington’s. These are movement disorders where motor patters are either unable to be started (Parkinson’s), or are abnormally being activated (Huntington’s).

Here is where things start to get messy. Just because the brain said “do butterfly Motor Pattern” doesn’t mean that’s what actually happened in real life. The Motor Pattern can only create the correct movement if it knows where your body’s pieces (arm, legs…) are located in space at all times. That includes where they are positioned prior to starting the motion and how they are moving during the Motor Pattern execution. That means sensory signals need to be coming up the spinal cord and telling the brain all this information. So let’s start from the sensory nerve and work our way up.

There are many types of sensation that feed into the brain including touch, muscle stretch, vision and joint angle. Together, they constantly tell the brain where the muscles and limbs are located in space. The fancy word for this is proprioception (proprio = Latin for “one’s own,” –ception = knowing). Even if one of these senses is blocked (like closing your eyes), the system can still work well enough for people to function. All these sensations come into the brain separate from each other, and they need to be integrated and processed into one cohesive signal. This happens in a group of neurons that make up the thalamus (Latin for “inner chamber” because it is located deep in the brain).

Tangent: If multiple sensory inputs report conflicting sensations it can have a nasty effect. This is why you get nauseas when reading a book in a car. The sensations from your eyes and inner ear are conflicting with each other.

Now that we have a Motor Pattern signal going down to the muscles and a sensory signal coming up to the brain, we need a way to compare what was instructed to happen (the Motor Pattern) and what actually happened (the sensory signal). This is a job for the little brain, or cerebellum in the original Latin.

The cerebellum gets as copy of the Motor Pattern being activated from the motor cortex as the signal is being sent downwards. The cerebellum also receives sensory signals from the spinal cord, specifically the ones about joint angle and muscle stretch (proprioception). Now that the cerebellum knows what should have happened (Motor Pattern) and what did happen (sensory input), it can compare the success of the Motor Pattern in real life.

The cerebellum doesn’t just compare these signals, it constantly adjusts the ongoing Motor Pattern to adapt and fit the circumstance at hand. That means the cerebellum sends its own signals to the thalamus and basal ganglia to instruct them on how to adjust their signal to better accomplish the desired motion. Even this complicated picture is a VERY simplified version of what we know happens, but I wanted to spare you the headache.

Now that we are all thoroughly confused and lost let’s ask ourselves an important question: What does this mean for swimmers?! Well, let’s use a real life example, like swimming the 200 fly, and see if we can follow all these nerve signals and see if they explain what we feel during a race or training.

At the start of the race, your brain chooses to activate the “Butterfly Motor Pattern.” These signals start in the motor cortex and travel down to the basal ganglia. No motion has occurred yet, this is what happens milliseconds before breaking the surface of the water.

The basal ganglia do two things at this point. They suppress all the other strokes’ Motor Patterns so you don’t start accidentally swimming freestyle or breastroke. They also start implementing the Fly Motor Pattern by sending the precise program sequence back to the motor cortex. The motor cortex then activates the proper motor units in the spinal cord in the proper sequence and with the proper power in order to create the motion of butterfly. This is all happening unconsciously because you have obviously practiced this Motor Pattern many times before.  

During all of this, your sensory nerves are telling the brain what all your limbs are doing and where they are in space and time. The signals from skin and eyes go directly to the thalamus, while sensation of muscle stretch and joint angle are processed through the cerebellum before they all coalesce in the thalamus. At first, the Motor Pattern butterfly you are supposed to be doing closely matches what you are actually doing. That’s because you are fresh and still on your first 50 of this 200 fly. So at this point, the cerebellum doesn’t have much to do but sit and watch.

It’s the third 50 now and something is going wrong. For some reason, the Motor Pattern you are supposed to be doing is not matching up with what is actually going on. Your arms are hitting the water too wide, your head is staying up too long, and your legs are sinking to the bottom. As your muscles fatigue and fill up with acid, those fibers stop working altogether. The cerebellum detects these changes and instantly starts signaling the basal ganglia to modify your stroke. It says things like “pull shallower” or “press deeper” and “keep hips up!” The cerebellum might go too far and start pushing the basal ganglia to switch to your “dolphin dive Motor Pattern.” But you’re a professional, so that doesn’t happen.

For every stroke, turn and dive there is a Motor Pattern written to streamline your movements and free up your mind to wander off. But what if you don’t like the Motor Pattern you have? What if your freestyle technique needs some work? The good news is that these Motor Patters can be re-programmed through Motor Learning.


Motor Learning: Writing Motor Pattern Programs

Do you remember learning to walk? No… I’m guessing you were too young. But even if you had memory from when you were 12 months old, you still wouldn’t remember learning to walk. That’s because some Motor Patterns are so important you are actually born with them. Walking, running and even swimming (although not our version of swimming) Motor Patterns are genetically imprinted in your spinal cord. We know this because even if you your spine is completely cut and separated from the brain, electrodes implanted in the spine can activate that “walk Motor Pattern” and the legs will start walking on their own.

Tangent: During the French Revolution, guillotined people would sometimes run away from the block…after their head was chopped off! Those motor patterns just don’t quit.

For most other complicated motions, a Motor Pattern has to be created from scratch. This Motor Learning process is done through performing the motion you want to Pattern. At first, you have to consciously control every muscle to create the motion that you want. All the while, the basal ganglia will be watching, and with repetition they will start to copy that conscious motion into an unconscious Motor Pattern. This fancy brain work is accomplished through neurons attaching and talking with other neurons. These new connections are real physical changes that you can see and they are what programming a Motor Pattern looks like under the microscope.

Of course, there is a catch. These new connections are built off the exact motion you are performing repeatedly in the water. If your motion is off or incorrect (bad streamlining for example), then your Motor Pattern is going to get stuck that way! Those neurons don’t know the difference between bad and good technique, they just copy what is being performed. Their job is only to automate motions you do on a regular basis. So, you better be engaged and thoughtful when you learn or teach swimming technique and demand perfection from the get go.

Tangent: This whole process of neurons creating new connections to other neurons is called Neuroplasticity.

Wait a second… if doing the correct technique and motion is all we need to do to create a Motor Pattern in our brains, then why do we do so many drills? Why take detours from normal swimming? There are two reasons for why drills are important. Firstly, drills are ways of breaking down a complicated motion into simpler and smaller pieces so you can give more focus to that one part of your technique. For example, doing 1-arm freestyle helps you focus more on developing the pull and recovery portion of your freestyle Motor Pattern. By eliminating the rest of the stroke, you can really control that one arm and make sure it is doing everything technically perfectly. The hope is that this mental training will transfer over to the full stroke later.

The second reason drills are used is because there is debate as to how the best Motor Learning is accomplished. Some people think Motor Learning occurs just as we described earlier. Performing the exact motion is what creates that exact Motor Pattern. Any errors in the performed motion will create errors in the Motor Pattern. This is called Closed Loop Motor Learning.

The other, and slightly newer theory, is that optimal Motor Learning occurs when motions and Motor Patterns are trained under multiple conditions. An example would be drills, swimming with fins, paddles and different speeds and stroke counts. Since the brain is constantly comparing what should happen to what did happen (remember cerebellum), these varying conditions create errors in motion. Swimming with paddles is not the same as swimming without them. This is an error and a deviation from the Motor Pattern that the brain must now adjust for. The creation and learning from these errors creates better body awareness and allows the Motor Pattern to adjust and adapt better under different situations. That means the body learns how to maintain the integrity of your stroke even if the circumstances are changing. This is called Open Loop Motor Learning.

Here is another example of how these two Motor Learning techniques work. Let’s say we want to develop the best possible free-throw shooter (this is for a sport called basketball in case you were wondering). If we used Closed Loop learning, the player would practice shooting the ball from the free-throw line with a regulation ball into a 10 foot high hoop over and over and over… If we used Open Loop learning, we would make the player shoot from different positions on the court, with balls of different sizes and weights into hoops at varying heights.

So, who would improve faster and become a better overall free-throw shooter in a real game of basketball? Counter to intuition, the Open Loop player actually does better! During Closed Loop learning (just doing the same free-throw over and over), the player developed a single, very rigid Motor Pattern based on only one possible circumstance. The Open Loop player taught himself body awareness and control under multiple circumstances. This way, his Motor Pattern could more easily adapt to changing circumstances like fatigue at the end of a game, growth of his body, sweaty hands…whatever you can think of.

In swimming, I think there is use for both types of learning. Younger kids just learning to swim would benefit more from Close Loop Motor Learning and using drills to focus their attention on developing a great baseline technique for all their strokes. As they grow older and have a well-developed stroke, using Open Loop training through equipment, stroke count and pacing can help them maintain their technique during changes throughout the season (taper for instance), growth spurts and muscle development.

Tangent: These theories were put forth by two scientist and were named Adam’s Closed Loop and Schmitdt’s Schema (Open Loop) Motor Learning theory.

No matter what kind of Motor Learning you are training with, there are always three major stages in that process. If you pay attention closely to your own stroke (or the swimmer’s you are teaching), you will notice these stages.

The first is the Cognitive stage when you are first learning how to swim a new stroke (dolphin kicking for example). Movements are slow, inconsistent and inefficient. On top of that, it takes a lot of mental effort because you have to control every movement directly. There is no Motor Pattern yet, so your motor cortex has to do all the work itself. Practice here should be technique focused with clear objectives and movement patterns. No variability should exists. That means no fins, paddles, pull-buoys, stroke counts, pace... etc.  

The second stage is the Associative stage. This is the “in-between” phase where some Motor Pattern exists and motions become more fluid. Conscious control is becoming easier and you only really need to focus when your body gets tired or is facing a new circumstance. Speaking of new circumstance, this is a good place to start adding in variable conditions like paddles and fins.

The final stage is the Autonomous stage. As the name implies, the entire stroke is now Motor Pattern dependent and the Motor Learning is complete. No conscious effort is required unless you are trying to modify the Pattern you have built (like getting a better early vertical forearm and such). Practice is now completely “results oriented.” That means we are looking or a time, tempo or stroke count, not necessarily a specific movement pattern. This can be expected under many different circumstances too.

Motor Patterns and Motor Learning are some of the most complicated topics in the field of science and there is still a lot to learn. But now you have a basic idea of what goes on in your head and hopefully you can use some of the points made to structure workouts, or at least convince your swimmers (or yourself) that you know what you’re talking about when it comes to practicing technique.


Karl Hamouche- Swim Smart founder
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