Ground Reactive Forces and "Jumping" for Power

Many of you will remember the many times I've said I almost couldn't care less about Tiger's head "dipping" during his swing. Many of you might not have known why I thought this wasn't a problem, and some of you knew... What's some schmuck on the Internet know when Peter Kostis, Nick Faldo, Johnny Miller, Brandel Chamblee, and goodness knows who else were all talking about what a bad, terrible thing it was?

Tiger's dipped his whole career. He dips when he wins and he dips when he's not winning. The dip is not a swing flaw, and here's a post and thread I've been planning for awhile...

I'm going to start off with two videos:

Next, here's a link to an abstract for a 2001 paper on parametric acceleration (Miura, K. (2001) Parametric acceleration--the effect of inward pull of the golf club at impact stage. Sports Engineering 4, 75-86.)

Now, consider these things:

• Jamie Sadlowski bends his left arm coming into impact.
• Tiger Woods dips his head quite a bit and then raises it and straightens his legs coming into impact.
• One of the pieces of nearly every good swing pattern (particularly with longer clubs) is to "jump" coming into impact.
• Ben Hogan had an extra cleat installed on his right foot so that he could drive forward and jump on the downswing.

There are two points here. The first is "jumping," and I'll talk about that briefly. First, "jumping" is not limited to "new" swings (like S&T;). Every swing uses jumping and extension or else you'll be bent forward, your head would be moving all over the place, and you'd have a heck of a time hitting the ground consistently. You'd swing the slowest, your divots would tend to be heavy, thick clumps of sod, and you'd quit the game.

Around P6 (club horizontal to the ground on the downswing), the clubhead starts to get heavy. It's being thrown, pulled, or generally moved towards the ground at a really high speed. Jumping and extending - by pushing the hips forward, straightening the legs, and feeling the left side of your body expanding as you push forward and rotate - helps to shallow the club's angle of attack and exit.

Between roughly P5 and P6 most golfers have (or should) regain roughly their address flexion in their knees and hips, so this sudden jumping move helps to "throw" or "kick" the clubhead at the ground, similar to how one continually yanks on a string attached to a rock to keep the rock twirling in the air.

The very act of "jumping" creates some of the parametric acceleration I've talked about. It's what "kicks" the club. Everyone should do this in their golf swing, and we teach it to the majority of people in our schools and individual lessons.

But if you want to super-charge your parametric acceleration, and REALLY add some extra kick to the clubhead, then you need to do more. You need to make the distance from your left shoulder to the ball smaller, THEN yank upward (which is "inward" relative to the circle at impact). (If you did nothing but yank without first shortening the distance, you might just swing right over the top of the ball.) Sadlowski "yanks" on the handle of the club by bending his left arm. Tiger shortens the arc by squatting down quite a bit and dropping his head so he can JUMP more.

How much power can you add? Standard jumping with no change in levels? 5% or so is a reasonable estimate. 10% is possible if you compress into the ground like Tiger.

The downside? There's little in the simple jumping I teach, because your upper swing center around which your shoulders are rotating stays fairly constant, but if you want the added boost of compressing and THEN exploding, ball contact may suffer. We've all seen Tiger Woods pop up the occasional ball, particularly with the smaller-headed 3W. Changing your levels down and then trying to time the explosion upward is difficult, and most of the time Tiger gets it but sometimes he doesn't. For Tiger, the tradeoff is worth it. Most of the time.

Here's a video of J.B. Holmes dropping his head significantly, and you might say he doesn't do any of the "jumping" or "yanking up" part, but remember the golf ball is on the side so "inward" pulling is also, in a down-the-lineview, to the left, and J.B. Holmes pulls hard to the left with his hips (this is part of the "clear your hips to get power" train of thought - downside is too many people get their hips open too early and end up coming well over the top with not enough forward drive... and their sequencing results in a LOSS of speed). Pause the video at the appropriate spots and you'll see it:

Here's Tiger again and you can see the compression and then the extension and jumping:

Now, do I ever use the second level of PA, the actual downward compressing and then exploding? Yes. If there's a long par five or a long par four that's relatively open, I'll tee the ball up a bit higher (a bit more margin for error) and try to compress and then jump like crazy. When the ball's on the ground? I rarely opt to for the added boost, no.

So, in summary, EVERYONE should "jump" or "extend" or they're giving up power. Not everyone is capable of the second level of parametric acceleration, but it's important to know that it exists and can lead to some faster clubhead speeds and bigger drives, and it's important to use as much as you can up to the point where your ballstriking suffers too much.

Footwork is overlooked a lot of times in the golf swing, but since that's the only way we're connected to the ground and the ground is pretty solid, it only makes sense that we use it for power. How far do you think you could hit a golf ball in flat-soled shoes on a pond? The ground is your friend, folks.

This guy really kills it. I was almost pulled into the vortex as I was recording it.

I literally made someone take a golf posture, move his arms back like he was swinging a club (no club, hands not even really touching), then swing forward, slide forward, and literally JUMP what felt like four feet in the air and four feet forward. He did this a few times, then tried to have the same feeling when he swung. Pictures after were incredible and his ball flight was twice as high.

Michael, I'm happy to expand upon this if you'd like, but I have a hunch you'll get this:

Secondary axis tilt at P7 when rotated through to the finish accounts for keeping the head and butt on the wall while still allowing you to extend (push your belt forward). In other words, it's the "forward" motion of the hips that keeps the butt on the wall in the follow-through.

At setup? I suppose it could, but you'd have a heck of a time getting set up comfortably because your distance to the ball would change, necessitating a wildly different arm angle at impact versus setup, and so on.

So I'd say that within a small range, sure, but once you get out of that it's not worth it.

Could be that you've overdone it and you're having trouble timing things.