By Scott Palmer.
Proprioception
(/ˌproʊprioʊˈsɛpʃən, -priə-/ PRO-pree-o-SEP-shən)
The sense of the relative position of neighbouring parts of the body and strength of effort being employed in movement.
I first started taking an interest in proprioception a few years ago while training for my level 3. I have always loved maps. The idea that our brain has its own form of mapping and we can influence this interested me.
This system is proprioception.
All maps have a margin of error. They are only as good as the information that is supplied, Like topographical maps our body map also has errors. These are areas where not enough information has been supplied to create a certain movement.
Throughout our body we have proprioceptors that tell our brains about the positions of the joints of our body and where they are in space. We have these receptors in our skin, joints, muscles and tendons.
Regions of our bodies such as hands, face, and lips are a lot more important to us in everyday activities so the amount of information stored in our brain about these parts is a lot more accurate. This allows us to make more precise movements with them. The more we move these parts of our body the more information is gathered.
Below is an image of Homunculus showing a physical representation of what our body map looks like. In this image the larger the representation of the body part the more space that our brain dedicates to this area.
Homunculu
Hold you hands away from the computer and shut your eyes, hold your hands out in front of you about a foot apart, now try and make your pointer fingers touch in the middle, most likely you will have missed or the fingers won’t have meet directly into each other. Play with your fingers for a while rub your hands together, repeat the same task and notice how they will meet easier this time.Try this.
You have just gathered more information and now the map has greater accuracy for this task.
The problem is that this solution is only temporary. If we keep doing this on a regular basis and over time it will become more permanent. If we stop doing this we will lose the accuracy. Movement creates more accurate maps.
Our brains can also map things that are attached to our body, A tennis player’s racket will be mapped as if it is part of their body therefore, after practice, a skier will be able to map their skis and poles.
Think of a dog trying to run through a door with a stick in its mouth or when a beginner skier’s tips get tangled in a sign or lift line barrier. This is because the skier’s brain hasn’t mapped how long their skis are. It shows what can happen if the information in our maps hasn’t been updated and we haven’t taken the time to subconsciously update our maps.
So how does this relate to skiing?
“Good Movement requires good body maps”- Todd Hargrove
Skiing is a sport of movement and balance, Proprioception is the building block of both of these things. You have to know where you are to know how to move.
The ski equipment that we use changes the amount that our bodies can move while maintaining balance. We need to update our maps through practise to allow for this.
Our ski boots limit our ankle movement and our skis give us a larger base of support in the sagittal plane. This allows us to move with a greater range of movement than we have ever experienced.
Have you ever told a beginner to move forward on the ski and they only move a fraction?
Their brain is telling them that they are at the end of their range of movement before they face plant. Their brains have learnt this after many failed attempts at walking as a baby.
Our brains have not learnt that because of their new equipment the range of movement movement has greatly increased.
If we take skiers and before telling them to change something, show them the range of movement at which they can move, the receptors will add this into our proprioceptive “map” and allow them to make more accurate movements.
Just like with our fingers in the above example.
Remember, this will only be temporary. The more we do this the more permanent the map will become.
How can we teach this?
Before every lesson at any level get your students to do some simple movements exploring the 4 movements of NZSIA just like you would before the first straight run. This will update their maps.
Rock all the way forward on their skis and all the way back, “feel the support that the boots can supply, feel the way that the pressure changes along the length of the ski”. Encourage students to explore the full range of movement.
Place two poles in the ground between their skis, one in front of the skier and one behind and see if they can get out from them without touching them.
Games such as head, shoulders, knees and toes are also refreshing our maps we can modify this game to add ski tips instead of toes.
These will give more input to there proprioceptive maps allowing our students to learn faster and make fewer mistakes on the hill.
In the higher end skiing we can focus more on our ankle joints. By being in a ski boot with thick socks and foot beds we are preventing the proprioceptors from detecting movement. As a result we may not have the greatest maps of this area.
We can improve this by skiing with our buckles looser and moving your ankle around in the boot, The more movement we do the better our brains understanding will be.
We can also do some balance training off snow with barefeet, practice balancing on one foot and move your centre of mass around while focussing on the feelings under your foot. Try the same thing on different surfaces – rough solid surfaces such as concrete will give more feedback to your proprioceptors.
So, next time you are teaching someone to ski or training yourself, instead of teaching them a new skill or working on a particular movement first try and explore what you/they already have, what is already there. Once you have mapped these movements you will have a higher success at improving them in the future.
References
NZSIA Manual
http://www.medicalook.com/human_anatomy/organs/Proprioceptors.html
Todd Hargrove https://www.bettermovement.org/blog/2008/proprioception-the-3-d-map-of-the-body
https://skimoves.me/2016/11/21/the-sr-stance-surface-effects/