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iacas

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iacas last won the day on January 19

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6,339 Legend of the Game

About iacas

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    LSW® Co-Author • 5SK® Director of Instructor Development
  • Birthday 03/23/1978

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    Erie, PA

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    Pro
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    Righty
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  1. iacas

    Will the New Flagstick Rule Become a Fiasco?

    And in a mixed group when there's a hiccup in communication, it will slow things down (or people will be putting without their preferred situation). Of course. This isn't going to average out to happening multiple times per round. Highly, highly, highly unlikely. Like thousands to one odds. It was far, far more likely to hit the back of the hole and pop up and out. Player perception is powerful, even though it's often wrong. 🙂 Yeah… https://lowestscorewins.com/tips/putting-with-the-flagstick-in
  2. Just wear rain gloves - they're designed to work when wet. Unlike those NFL gloves.
  3. iacas

    Speed from the Arms in the Golf Swing

    So slow swingers are just standing in the wrong place on Earth? 🙂 I'm teasing… I imagine what you're talking about is two-fold, because there are basically two ways in which the ground "aids" us in making a golf swing: The feet are sitting on the ground and are thus able to use some friction throughout the swing. There are what we call "Ground Reaction Forces," but of course the key word there for you is "reaction." The ground reacts to the forces we generate with our muscles, and really, except for the shear forces in the bullet point above, the vertical GRF are really rather small in terms of their ability to generate speed. The ground is an inert platform. The first bullet point matters quite a bit more than the second bullet point. Chris Como was still able to swing a club pretty fast while falling through the air, but because he couldn't push off in the horizontal plane (shear forces, frictional forces) his lower body actually twisted the other direction because he was nearly in a "conservation of angular momentum" type of system. His upper body only had his lower body against which to act, so the force of swinging his arms down twisted his lower body the opposite direction. We know the former matters significantly more than the latter because we've measured the golf swings of thousands of golfers now on multi-million dollar systems. The conclusion: the vertical GRF, though a greater force, contributes very little to the rotation of the golf swing. The moment arm isn't very large and though the GRF can be quite large in summation, if your wrench is only two inches long it's gonna take a helluva lot of force to unscrew the stuck bolt. The moment arm is "d" on the right image below. And again, while "F" can be pretty big, because we're standing on the ground, the vast majority of our force is upward, creating a short moment arm. And… we know this is true because of the thousands of golfers tested on these multi-million dollar machines, some of them don't even generate a moment arm. Their forces are upward, but not forward of the COM, resulting in no moment arm. Some golfers generate a moment arm, but it's in the WRONG direction. And guess what? They're still capable of swinging fast. The smaller the moment arm, the worse the golfer tends to be (their swings usually bottom out too early), but the actual difference in swing speed is very small. They can still swing quickly. (Why? Spoiler: because the arms are responsible for the majority of the speed in a golf swing!) Optimization of any individual's COM within the confines of a golf swing would contribute small single digit percentage increases in swing speed, and that's in the most extreme cases where players had no moment arm or had one slightly behind their COM. Now, as to the first bit, the shear forces or "frictional" forces… you've previously cited swinging on ice. In many ways, arguing that because we can't swing on ice because we don't have friction is pointless. It underscores the purpose and role of friction, absolutely, but it doesn't say anything about whether our arms or legs are responsible for actually making the clubhead move quickly. And, it's also silly because we pretty much always have friction. These frictional forces, compared to the vertical GRF, are relatively small, particularly under the trail foot. The trail foot is progressively unweighted during the golf swing, so for it to slip out requires less and less force, and yet we rarely see a golfer's trail foot flying out. And when we do see a golfer's trail foot slipping out, we see two things: a) the golfer's trail foot doesn't exactly go flying out like it's under some tremendous force, and b) the golfer continues to swing pretty quickly. In case you're arguing that because the forces are measured at the ground, the things touching it (the feet, which connect to the legs) are responsible for that force… imagine standing straight up and down and punching or swinging upward. The force and speed generated in that situation is entirely coming from "the arm" and yet we'd measure forces in the ground. That doesn't mean that, aside from holding up the person's body, the speed of their punch or swing still comes from the arms. Just as in the golf swing. Now, among missing the points presented against you, you missed the point that Dave and I have visited these multi-million dollar labs that are conducting high end research on this thing, and we've tested out various theories and things. We've had Dave jump in the air, while swinging a club, freeing him from the ground. It's similar to the Chris Como video jumping from a diving board. And guess what? Dave was still able to swing really fast. Well over 50% of his normal swing speed, despite the fact that while in the air his lower body (like Chris's in the video), his lower body would swing in the opposite direction. (It didn't rotate very quickly, partly because of the basic physics [Dave's waist downward weighs more than Dave's arms and a golf club - which again demonstrates that the frictional forces are pretty small.) So, the ground reacts (reacts - it doesn't "do" anything itself) in two ways: vertically and horizontally. The vertical forces are often large, but don't result in much swing speed. The horizontal (shear) forces are relatively small, but "result" in more swing speed. So, just because the legs are touching the ground, doesn't mean that they're responsible for the bulk of the speed in the golf swing, just the same way as punching or swinging up will show forces against the ground without the legs doing anything. Look, a number of years ago Dave, I, and some others went to see Dr. Kwon in Texas. We've visited with Dr. Duffy at Penn State. We spent days not only talking with them, but goofing around in their multi-million dollar rooms with their very expensive and accurate systems. And we'd ask them questions, many of which we already knew the answer to. One of those questions, on a trip that was almost entirely to talk about vertical GRF (it was the hot thing at the time, and in our opinion, very over-rated, but the golf world was suddenly keen to explore it because we had all these new multi-million dollar toys), we asked Dr. Kwon "so what would a golfer have to do to swing faster? What's the first thing you'd tell him?" His answer: "Swing the arms faster. The vast majority of a golfer's swing speed comes from swinging the arms." And he'd know. But we already knew the answer, because we're not dumb. In fact, I'm pretty damn smart, plus we'd had years where simpler machines (only many thousands of dollars, not millions) captured graphs like this: I'll be honest: I'd typed out a whole long paragraph explaining how this graph demonstrates that the arms are doing a LOT of work against the platform the chest (not only to maintain the chest's acceleration but to further accelerate the arms beyond that, and ultimately the bottom of the double pendulum - the shaft of the club), but I'm not sure you'd get it, and I've already spent way too much time on this. I'll finish this little section with this: Ph.D.s will tell you that the majority of a golfer's swing speed comes from the arms. The chest and hips turning through help, the "jumping" helps a tiny bit, but the majority easily comes from swinging the arms through space against the platform of the chest. Why put out a hokey video instead of just saying "this is a known fact, confirmed by multi-million dollar machines and plenty of guys and gals with Ph.D.s in biomechanics"? Because, generally speaking, people are more likely to believe things when you show them little examples that they can understand. They don't like to just be "told" "this is a fact," they like to see it in a way that makes sense to them. You cannot do either of these things, because you have neither the facts on your side, nor do you have any cutesy examples where you can show how swinging without the arms generates a majority of the swing speed. You cannot conjure even a thought experiment, like I could wherein I suggest that you swing on a bed of pillows and springs, thus providing only shear force friction and not much in the way of vertical GRF, and it's easy to imagine how you can swing almost as fast doing that as swinging from a solid block of concrete. You cannot do these things because you are wrong about where speed comes from in the golf swing. The majority comes from swinging your arms. I don't like anecdotal stuff, and I hate feels, but occasionally anecdotes are explanatory. A good player on a local high school team tore his ACL and MCL just prior to the state championships last fall. He played, in a full brace, and couldn't really turn. Heck, walking was tough for him. He mostly had to make an arm swing with a little bit of what people classically call "shoulder turn." He lost about one club's distance… because he could still swing his arms. They are more important in this context, because the context here in this topic "speed from the arms in the golf swing," and the fact of the matter is that they contribute the majority. The discussion is not about whether "any weakness in the chain will lead to a leak of power and inefficiency." Of course that's true. But that's not relevant at all, and is basically the same thing as me saying "This is not important because the arms are connected to the torso at the shoulder." So what? That's not what we're talking about here. No shit. And the arms are responsible for the majority of the clubhead speed. That's not an argument. This isn't a lesson, and nobody here is telling anyone to "focus solely on one aspect." Thanks for helping with my procrastination. Correct. TL;DR: @Righty to Lefty doesn't know what he's talking about, so he hopes that by talking often enough about loosely related things, he can score some points. Ph.D.s and their multi-million dollar machines will all tell you the same thing: the majority of the speed in the golf swing comes from the arms.
  4. iacas

    "The Comics" Thread

    Ball Speed: The Mysteries of Breaking Putts on Fast and Slow Greens Ball Speed plays an important part in shaping the roll of your ball on the putting surface. You can't control the slope or speed of the green, but you can control how hard or soft you hit your ball. I'll bet you guys didn't know this! Your ball accelerates as it moves away from your putter, then goes a constant speed for awhile, and then finally begins slowing down. There are three phases to all putts: the acceleration phase, the constant phase, and the deceleration phase. You know it's true because people with "Dr." in the title of their name apparently say so! Wow!
  5. iacas

    Golf Ball in the Ocean

    I don't doubt that it's a bit of a problem. That's a lot of golf balls in a place they don't really belong.
  6. Day 340 - January 19, 2019 - SuperSpeed work plus a little work with the backswing.
  7. The chart, in larger form: I think two things: Though there's a definite trend, those are some pretty small numbers. What Dave said is important, I think: A 40+ year old on the PGA Tour has made his money, has a family, is content, etc. They're less motivated, they don't practice as often, and so on. P.S. I putt better now than ever.
  8. I saw your launch angles in the other topic and they seemed a bit too low. What do you think?
  9. iacas

    Let's Talk about Grips

    Unless you go PURE, you can never be SURE. 😄
  10. Let's stick to the topic here please. It's not the club fitting or the facility. Just use "iacas" or the link at the bottom of the page: Purchase SuperSpeed Golf Training Bundles | SuperSpeed Golf Store Contact SuperSpeed Golf if you have questions regarding your order or products. I do ask that you also put the "iacas" coupon code in when you get to the order page, like this: Thank you. If you buy this way let me know and I'll make you a Supporter here at TST for awhile. https://superspeedgolf.com/our-bundled-products/ref/iacas/
  11. iacas

    Playing Golf Without a Thought

    Two quick comments: Stopping mid-swing is not a swing thought. It's not what we're talking about here. Don't poke at people. That's not what the OP is about, nor is it the point of the discussion.
  12. Day 339 - January 18, 2019 - Putted against @NatalieB for 15 minutes or so.
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