WEBVTT

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In this Golf Smart Insight, we're going to talk about going normal.

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So first, let's define what normal is, and that's actually fairly tricky,

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because there

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are a couple different ways that you can define going normal, depending on your

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reference

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point.

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A normal force is essentially a force that's perpendicular.

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So in physics class, we always had, you would start with the equation with

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gravity is going

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straight down, and normal force is going straight back up at gravity, because

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they're perpendicular

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to each other.

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So the normal force when I'm swinging something, we can go back to head cover

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swing.

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So if I was to swing this object like so, essentially what will happen is I'm

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going

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to give it a little bit of a linear force to kind of get it going, and then

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boom, I'm

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going to get into a normal force like so, which basically I'm going to be

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pulling away from

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the direction that it's rotating, and that's going to cause, so it's going this

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way, because

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I'm pulling this way.

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It's essentially a normal force, because I'm pulling away from where the mass

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is kind of

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going out away from me.

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Okay, so how does that apply to the golf swing?

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Well, there's a couple different ways that you could define your normal force.

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You could define the normal force just based on the instantaneous axis that the

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club is

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swinging around, or you could define the normal force dependent on your body.

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Now because of how I look at 3D and tend to talk about the golf swing, I tend

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to defer

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more towards defining it based on a global scale or looking at your body.

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So in the global scale, a normal force is going to be dead up this longitudinal

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axis.

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So when the force is coming straight back towards me from this shaft, the force

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is normal.

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Anytime that there is a difference between where the force is and where the

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shaft is,

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it would not technically be normal.

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It could be going normal, it could be going away from normal, but it would not

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technically

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be normal, where in the instantaneous axis method, basically if the force is

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not going

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in the direction of the target, it could be considered normal, which there was

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a famous

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paper by Nesbitt and I believe he used that method for calculating normal force

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.

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So when I'm talking about normal force, what I'm typically referring to is the

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point where

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everything is kind of being pulled out and the force is going straight up and

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down that

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shaft.

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So at that point, you're basically going to have, you've maxed out your ulnar

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deviation,

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you've maxed out your elbow extension.

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In our particular case, you've had some form rotation to help get that even

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further away

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from you, but basically the grip is as far away from your body as you can get

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it.

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And it's not possible to have that point be at impact and further out at the

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same time.

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So at impact, if you were to look at it, and if you look at what Sasha Mack

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enzie presented,

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there's definitely kind of these competing forces that are hopefully trying to

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somewhat

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balance out so that the force is coming somewhere back up towards me, but it's

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not completely

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normal if you're using the body as the reference point until it gets out in

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this position and

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you feel kind of that little bit of a tug.

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Now the normal force is frequently described as a pulling motion and as you saw

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with the

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head cover swings, that makes a lot of sense.

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But for some golfers, feeling like it's pulling motion may not make the most

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sense.

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So here would be the analogy.

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If you were doing a pull up, so imagine you got a bar above you and you grab it

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, you're

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going to pull yourself up and then you're going to pull yourself down.

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If that makes sense to you, then yes, this is going to be a pulling motion

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because essentially

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what's going to happen is in this pull up, I'm going to use the muscles in my

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back and

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my shoulders to pull myself up.

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And then those same muscles are going to be acting while they're lengthening or

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doing

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what's called an eccentric contraction to lower myself down.

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But the forces going through my body are the same muscles that pull.

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And so if you were to measure them, they would still be working away from me in

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a pull

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direction.

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It's kind of what's happening here is when I go through and as I'm working

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towards normal,

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the club is moving away from me and my elbows are straightening.

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So all these things are lengthening out as my body works slightly backward.

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So I'm pulling even though it's going away from me.

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So that's where I think some of the confusion as far as the application of how

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to go normal

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can happen, the majority of the normal force should happen from the legs

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pushing the upper

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body back and away as your arms release.

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And that creates this tug on the club.

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What a lot of amateur to do is they get to kind of this point of no return

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where you've

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got no access till becoming very, very steep.

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And so they will pull their arms in and create the normal force this way.

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Every golfer, virtually every golfer I've ever looked at creates a normal force

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down

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near impact.

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It's just a matter of how they do it, which is going to dictate how much

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success they're

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going to have with their swing.

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I think that should help clarify what I mean when I'm discussing going normal.

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I know that everybody else can have different definitions depending on their

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perspective.

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I just want to clarify mine.