The nervous system, so we just briefly
touched on the nervous system yesterday. Now we're going to get a little deeper.
So my movement,
my movement, how I move, how I take the jump shot I take today
is going to be based on my intent,
how do I want to take that jump shot?
Do I want to take a set, standing jump shot, do I want to jump while I take that jump shot?
Do I want to jump
and jump high enough to get over a defender's hand?
Do I want to do a fadeaway jump shot?
All that's my intent.
My past experience, have I done this before?
If I have done this before, what was successful, what was unsuccessful?
My internal feedback -
Golgi tendon, muscle spindles,
where my body is in space,
based on my internal receptors.
My external feedback -
if we're talking about that same shot, the floor, can I see the floor? If I jumped off the floor,
was there a wet spot on the floor? Did I slip?
My defender, is he terrible?
Is he good? Is he big?
Does he look mean? Does he look like when I jump up, he's just going to hit me?
All of this stuff has an affect
on motor planning. And motor planning is just writing that program,
it's going to recruit the right muscle fibers
in the right muscles to create the motion I want,
that will also affect something called the gamma
motor system, which you can think of as controlling
- I'm going to say it, I'm going to say it, we've been beating ip up for 10 hours, but now I'm going to say it the way it's supposed to be used -
controls tone, the amount of activity in a muscle.
You have all these proprioceptors,
you guys learned a little bit of this right?
Golgi tendon organ and muscle spindles. So I'll give you my take on it.
Review is good, then we'll talk about some other receptors.
Muscle spindles, what do muscle spindles,
what do they rate, what are they trying to give you information on?
Write this down for me. Your muscles spindles are your
"stretchometer." I want you to think about one of those little, the old-school
valve and there's a little needle.
And it gets pinned this way, if I had a red marker.
Over here would be warning level.
And then this is okay.
And this is calm you with me on this one?
That's a "stretchometer," this is your muscle spindle.
Muscle spindle = stretchometer.
The thing I want guys to keep in mind is it's not just
how for you stretch,
it's also how fast
you stretch. It's rating stretch
on an intensity basis. How far and how fast
and how long you hold that stretch.
Now, muscle spindles set up a reflex, do you know what that
reflex is? You're going to laugh when I write this down.
You've never heard of stretch reflex?
So if you pull on a muscle spindle really, really hard it sends a signal back to my
the tells that muscle to do what? Contract.
So it increases muscle activity.
Increases muscle activity. Where's someplace that we see this happen?
Quads and hamstring. How?
We'll take that into consideration in a second, you're actually
combining a few different receptors with something like PNF stretching.
Where's something where we see just stretch receptors be inactivated
and this response? So you're stretching your calf
and it goes, "Mmm, I don't think so," and just cramps up and you fall over.
Sure, I've never actually seen that happen, but we'll say that's good,
that would be a good example. Have you guys ever seen um
you guys ever done a high kick? You like that for my high kick, was that good?
If I just do this,
did my leg just fall to the ground at the speed of gravity? No, it was quicker, right?
I didn't force it down. Did I squeeze my glue to get that down?
No. What hit the end of its length?
So the muscle spindles in my hamstrings went (grunt)
"That's far and fast for you, Mr. Tightness."
Could be, there could be something in there about charley horses.
But let's keep it simple for now. I just stretched my hamstring really, really hard
which sent muscle spindle sent a bunch of signals back to my
spinal cord and my spinal cord told my hamstrings to do what?
Which pulls my leg back down real quick.
Does that all make sense?
The elastic limit would be adding how far your connective tissue is willing to stretch
to this okay. So let's look at
Golgi tendon organ. Did this help? You understand muscle spindles a little bit.
Golgi tendon organ equals,
what do they rate? "Tensionometers."
Remember this is not just how much tension
but how fast that tension starts building up.
Reflexively, what does that make your
body want to do? If you build up too much tension in a muscle what eventually
It fails. Not due to fatigue
but just literally you'll go to
and it shuts you down.
That's a very extreme version of this.
Does anyone know what that reflex is called that Golgi tendon organs are probably responsible for?
Autogenic inhibition, ever heard of this? What does autogenic probably mean?
Automatic, -genic referring to within the same muscle.
Inhibit means to stop it.
So this decreases muscle activity, reflexively.
Want to see how this works. I'll give you couple quick examples.
Everybody back your chairs up away from your desks. Now I just told you that you probably
don't need to stretch your hamstrings as much as you thought you did
but we're going to hamstring stretch because it's just an easy example.
I want you to sit at the end of your chairs.
I want you to straighten out one leg. On that leg, go ahead let your foot plantar
flex, I don't want to
stretch your sciatic nerve, I just want to stretch your hamstring.
Make sure your knee is locked. I want your to keep your spine nice and straight for me
so that you tilt at the pelvis, we get as much hip flexion as we need to
to stretch straight leg hamstring.
I want you to just go to a point of mild stretch.
Once you're there you have to pretend like
you're not easily distractible and
you have to stay in one place. As soon as you went into a stretch, what did you feel
an increase in?
Stay with me on this one. That increase in tension
Muscle spindles were triggered by the stretch.
They sent that signal to my spinal cord
which then sent a signal back to my muscle to contract. That's not we wanted with
the stretch now is it?
But if we hold it long enough what you'll feel is a buildup in
tension will eventually start signaling who?
The GTOs. The GTOs go, "Wait, wait, wait, wait.
That's stretch but that's not that bad.
Now you're building up tension, I don't need it." So what is the GTO start doing if you hold
this long enough?
Causes you to relax. Has anybody got that relax yet?
There you go, so there's a little example of how those
two things are related.
It can, the problem with this is,
which ones more reactive, which ones easier to turn on?
Muscle spindles. A lot of the research you have seen where it says
or you have to hold a stretch for certain amount of time,
it's probably thirty-plus seconds, that has to do with the fact that
muscle spindles react faster than the GTO
and for most people it takes a little longer
to settle in, stop moving around and let autogenic inhibition do its job.
Make sense? Cool.
Want one more thing about the muscle spindle and GTO?
Everybody stand up.
Put one arm out in front of you.
Close your eyes.
You have to keep your eyes closed...don't you open your eyes.
Now, you have to take your other hand
and make it level with that hand. Open your eyes.
You cats are amazing. How's you do that with your eyes closed?
There's a little example of how
the GTO and muscle spindle are related proprioception.
You did this. What did you increase here?
Tension. What did you increase here? Stretch.
You stretched out your lat a little bit, your teres major a little bit
maybe your sub scap a little bit.
Maybe there's a little tension in your anterior delt, so what did your body have
to do on the side?
You have more receptors than just GTOs
and muscle spindles. You have things called Ruffini endings
that deal with things like lateral
stretch, which is like pulling that we see on fascia,
as well sustained pressure and they'll decrease sympathetic activity,
which has to do with your autonomic nervous system. Pacini corpuscles,
rapid pressure change in vibration.
You have a vibration receptors, did you know that? They're in a lot of different places,
you have vibration receptors.
Crazy right? Vibration receptors.
Type 3 & 4 interstitial receptors,
these are some of your pain receptors.
Have you heard the term nociceptors? They give you a noxious stimulus
and tell your body that, "Hey,
whatever's going on right now right here probably not a good thing."
All these different receptors give you
awareness of your environment, where your body is in space,
how you're moving which your central nervous system then organizes
and creates a motor program,
just like a computer program, to react to,
with the intended movement that you'd like to do.
Talk about a rabbit hole. You remember that little
thing we did yesterday where I was like, "Just imagine if you thought about every muscle
that affected flexion and all the ligaments around that joint,"