A company called Bentley Kinetics is changing the way golf is taught and learned. Michael Bentley, the company's driving force, has had an interest in biomechanics for decades. Since 1991, he's been working with physicists, NASA engineers, sport physiologists, bio-mechanists, athletic trainers and strength coaches. In doing so, he has created the sport industry's most innovative wireless motion analysis system, the K-Vest.

By using wireless sensors, Bentley Kinetics has eliminated the need for expensive high-speed cameras ($20,000+) and software that would take days or weeks to analyze one golf swing. Instead, the K-Vest can produce a person's swing data in a couple of seconds. Now that's fast!

Not only that, the K-Vest can capture a golfer's motion in real time and identify the errors immediately via live animation so that the golfer can make necessary changes to his/her motion.

Here is a golfer doing an exclusive exercise only possible with the K-Vest. He can see that his hips are out of position (indicated by the red color of the hip segment). When all segments are in their correction position (indicated by the color green), the golfer will be alerted by musical tones. So one can learn by watching and listening, which allows the golfer to learn at a much faster rate.

Also, there is no guessing as to whether or not improvements are occurring. No more looking at the video to see if a small change in movement is perceivable. Numbers don't lie. And the K-Vest will produce numerical data that will positively confirm whether or not change is occurring, good or bad.

Understanding the data

More importantly, Bentley Kinetics has made it easy for laypersons to understand the data that is gathered. By having targets, students can understand where their swing is correct or maybe where it's going a little astray.

The data has been categorized according to the different areas of the swing. It can easily check simple elements such as posture angles, alignment, and backswing rotation in degrees.

Better yet, complex movements are monitored just as easily and are plotted on a graph. Measurements of core stability, the loading and unloading of the K-factor (similar to X-factor) and the kinetic chain, which compares the peak speeds of body segments, are transposed to a graph. This allows the golfer to see whether or not his/her body segments are firing in the proper order. One can also see whether or not there is the proper amount of body segment speed, which allows the synchronization of the swing.

Make sense? Let's take a closer look at some data.

Kinetic Link: Firing in the proper order

Most people understand that any athletic movement starts from the ground up. For example, when a baseball pitcher finishes his windup, he will push off the mound with his right leg (if he's a lefty it's the left leg), then fire his hips, then shoulders and eventually his arm and hand. Bentley and other bio-mechanists call this the "kinetic link."

According to Bentley, the kinetic link can be summarized as the body's ability to create maximum speed and power by properly sequencing body movement. In the case of golf, baseball, tennis and other athletic events, the main objective is to efficiently transfer energy from the ground, through the body, out to the arms and ultimately into the club, bat or racquet to achieve maximum velocity at the point of impact.

Key to reading the graphs

• Red line = Hip segment rotation speed (degrees per second)
• Blue line = Shoulder segment rotation speed (degrees per second)
• Green line = Arm segment rotation speed (degrees per second)

This graph depicts a scratch (zero handicap) golfer's kinetic chain. The x-axis is a timeline while the y-axis shows the rotational speed in degrees per second. The left half of the graph shows the backswing with negative values and the downswing is on the right hand side of the graph showing the positive values.

For the purpose of analyzing the kinetic linkage, take a look at the peak values. The correct kinetic chain shows that the hips fired first, then the shoulders and then the arms. The peaks are displayed with the red triangle for the hips, the blue dot for the shoulders, and the green square for the arms. According to the K-Vest, this is almost ideal.

Firing out of order - Hands first

Contrast that with an average golfer with a 20 handicap. This golfer fired his arm segment first, then hips and shoulders. As you might imagine, this means he was casting the club on the downswing.

Shoulders firing first

Here's a 16-handicap golfer with a lot of power but who is not very efficient at developing that power. His shoulders are firing before his hips and it is no wonder why he comes over the top. He's been working on flattening his downswing plane for years but could not ever get it right. Maybe because you can't fix an effect when the cause is not being properly addressed?

These are just a couple of ways that golfers can have difficulty getting the order correct for their kinetic chain. And there's more...

Synchronization: New way to quantify

As I had emphasized in last month's column, hand speed is critical in obtaining a level of synchronicity. The K-Vest enables the teacher and student to calculate another important dimension of synchronicity. To understand this new method, let's take another look at the data from our scratch golfer.

The Double, Double

According to Bentley Kinetics, an efficient and effective kinetic link will show that the shoulders should have approximately doubled the rotational speed of the hips and the arms will have doubled the rotational speed of the shoulders.

This is a good numerical definition of synchronicity that takes the mysteriousness out of the word. We know a synchronous swing when we see it. When Ernie Els or Stuart Appleby hit the ball over 300 yards with little apparent effort, that's very synchronicity! But how does the average Joe golfer develop a swing like that? Not by swinging slow and smooth! The only way to do that is to develop high amounts of segment speeds that are firing in the proper order AND having the double, double energy transfer rate to the subsequent segments.

Let's look at the numbers to make this clearer.

• Max hip speed = 426.94
• Max shoulder speed = 697.56
• Max arm speed = 1653.26

If you look at the Transfer Ratios, his hip to shoulder ratio (dividing the max shoulder speed by the max hip speed) is 1.63 and his shoulder to arm ratio (dividing the max arm speed by the max shoulder speed) is a large 2.37. A double, double would elucidate the ideal 2.00 transfer ratio in each linkage. So while he is not perfect in obtaining the double, double, he does have a pretty good level of synchronicity.

Average Joe's dilemma

Let's take a look at a 15-handicap golfer's data.

Here are the numbers.

• Max hip speed = 496.43
• Max shoulder speed = 743.27
• Max arm speed = 936.03

While the segments are firing in the correct order, a look at the transfer ratios shows a lot less efficiency. From hip to shoulder it is only 1.50 and the shoulder to arm ratio is 1.26.

The scratch player had less hip speed than the Average Joe yet was able to transfer more of that energy into creating 76% more arm speed! The bottom line is that the scratch player generates 115 mph of clubhead speed while the Average Joe only swings at 85 mph. That translates into the scratch player hitting drives more than 60-70 yards past the Average Joe.

The good news is that Average Joe now knows what to work on. And getting better may take time, but as long as he's working on the right things, progress will be made.

Limitation of video analysis

As you can see, the kinetic link is the most effective and efficient way of using your body to perform athletic events. But seeing and measuring a golfer's kinetic link using traditional video is impossible. That's right, IMPOSSIBLE.

As a golf teacher using the latest high-tech digital video systems from Astar, V1 and JC video systems since the early 90's, I can honestly say that video cannot possibly determine with 100% certainty, the correct firing order nor the segment speeds.

It's much like the difference between having an X-ray or a MRI done for a torn ligament. One is a 2D image that might be good for seeing large bone structures, while the other is a 3D view of even the smallest of tears in soft tissue.

So if you want to improve at golf but can't seem to get things right no matter how hard you work, maybe you need an MRI to verify what's the real problem? Otherwise you might be putting a band-aid on when you really need surgery.

Not that the kinetic link is the only thing golfers do wrong, but the main point is that the video analysis cannot accurately track nor determine the "grey areas." How would one know whether or not a minute error has been corrected sufficiently? How would a golfer determine whether or not his/her hip is firing fast enough but not too fast? How would a golfer know when his/her shoulders are firing at the right time? Because beginners' errors are obvious, they are easy to see using video. But advanced golfers need an MRI to see their flaws.

The Future

The K-Vest is a fantastic tool for analyzing any athletic movement, not just golf swings. Wireless motion sensors have been around for nearly a decade already but it took Michael Bentley, his team of software designers, bio-mechanists, and other scientists to make this simple and easy to understand. In ensuing articles, I will conduct tests with the K-Vest to analyze different types of traditional training methodologies for different sports to determine their effectiveness at improving an athlete's kinetic chain.

If you are interested in a K-Vest lesson and are on the mainland, contact Brian Vermilyea at mailto:bvermilyea@bentleykinetics.com?subject=Feedback from AroundHawaii.com to find out where a K-Vest instructor might be located in your state.

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