Pelvis Power in the Rotary Athlete

13 Dec Pelvis Power in the Rotary Athlete

Understanding the kinematics of the rotary athlete assists in determining efficiencies, inefficiencies, and power sources with the throwing and striking motion. The hitting, throwing, and swinging motion all have a very common signature as it pertains to the pelvis action relative to efficient energy translation and power development. Regardless if you are position player in baseball, tennis athlete, pitcher, or golfer, research indicates all of these athletes have similar kinematic sequences and invariably show a very similar anterior to posterior pelvis motion.

Prior to providing some examples and specifics on this pelvic motion first recognize the data based which this signature is drawn from is a combination of data provided by the Titleist Performance Institute, K-Vest Motion Learning, and AMM 3D Motion Analysis. Research provided from theses aforementioned companies consists of a data based of well over 1,000 PGA, LPGA, MLB, and NCAA level athletes athletic actions. The 3 dimensional motion analysis of these individuals athletic actions have provided a model of efficiency. This model of efficiency termed the Kinematic Sequence provides viewers the ability to identify efficient kinetic chain sequencing, speed translation through the body, inefficient movement patterns, rotational velocities, anatomical positioning, and the processes by which power is developed within these rotary based athletic actions.

In this day and age we now know without a doubt the process by which these athletes develop bat speed, swing speeds, and throwing velocities. We can also identify inefficiencies within these athletic actions deterring from speed translation and development. No longer is the process of power development subjective as it pertains to the rotary based athlete. The only component to now decipher once data is captured on an athlete in 3D is: “if inefficiencies or power leaks are present is to determine the reason behind these inefficiencies”.

Typically, the inefficiencies will fall into the “physical bucket” or “mechanical bucket”. Physical referring to dysfunctions within the kinetic chain limiting the athlete from performing the athletic actions of throwing or striking. The physical dysfunctions can for example be rooted in mobility limitations, stabilization issues, or other kinetic chain based issues. The mechanical side of this equation pertains to limitations by the athlete in the actual execution of the throwing or striking motion. The athlete is not executing, sequencing, or timing the throwing or striking motions correctly.

The Kinematic Sequence is the model and shows the process by which a rotary athlete translates energy in a definitive sequence to bat, ball, or club. This sequence within the kinetic chain involves the acceleration and deceleration of segments. Recognize these segments are accelerating and decelerating in multiple vectors of force. The body operates in 3 dimensions and as a result speed translation is not just linear. Looking at the example below we can see an efficient Kinematic Sequence of a PGA Tour level golfer.

Efficient Kinematic Sequence

The Kinematic Sequence shows the acceleration and deceleration of body segments into the impact position. On the graph above the Transition Line indicates where rotational velocities go positive and begin the translation of energy into the golf ball. To simplify this graph Line A is the Pelvis, Line B is the Thorax, Line C is the Lead Arm, and the Blue Line is the Club. Review of this Kinematic Sequence shows an acceleration and deceleration of each segment within the kinetic chain. I like to refer to efficient acceleration/deceleration of body segments looking like “ski slopes”. You go up one side of the hill and then down the other side. There are no bumps or flat areas going up or down the slope. This is an indicator of a very efficient transfer of energy from each body segment to the next in the chain into the club. Initial review of 3D Motion Analysis will review the Kinematic Sequence to determine the efficiencies in which the athlete transfers speed. Secondly, the acceleration/deceleration components will be reviewed.

Now that we have viewed an efficient Kinematic Sequence and know what to initially look for in the data capture. Let us take a look at an inefficient Kinematic Sequence in order for you to understand visually the differences. An efficient Kinematic Sequence will most likely show the sequence being out of order, poor acceleration or deceleration of segments, or issues with anatomical positioning.

Inefficient Kinematic Sequence

Looking at the above Kinematic Sequence we see a very different graph than the one discussed previously. If we take the same analysis steps and review the sequence. We can see the segments peaking in the incorrect order. The inefficient Kinematic Sequence shows the lead arm peaking first, followed by the pelvis, the club, and thorax then peaks after this golfer has hit the ball. Secondly, looking at the acceleration/deceleration components of each segment, I am not seeing to many nice “ski slopes”. I see the Pelvis – A not really accelerate or decelerate, the thorax (B Line) has almost a plateau in the middle of the hill, the lead arm accelerates nicely, though the deceleration of this segment is not very good. The club (Line D) looks pretty good in terms of acceleration and deceleration though inconsequential due to sequencing. If I were to take a guess at the “swing fault” of this golfer I would say an over the top move as the lead arm and club accelerate at a very high rate right from the transition with very little lower body action, and the thorax not decelerating until after contact.

At this point we have provided a review of the kinematic sequence with a golf swing. The golfer is only one type of rotary athlete with a Kinematic Sequence. Below are examples of a professional position player in baseball hitting and a pitcher. You will see a very similar Kinematic Sequence signature on these athletes relative to the golfer. Please note the sequence for the pitcher (overhead throwing athlete) is slightly different with the following sequence occurring: 1 – Pelvis, 2 – Thorax, 3 – Lead Arm Extension (throwing arm), and 4 – Internal Rotation of Lead Arm (throwing arm).

Baseball Hitting Kinematic Sequence

Baseball Pitcher Kinematic Sequence

In both of the rotary baseball athletes above we can see a sequence, acceleration, and deceleration of kinetic chain segments into release point or contact. The data also indicates a signature kinematic sequence similar for all rotary athletes. Regardless, if you are a hitter, pitcher, or golfer, the process by which the kinetic chain transfer speed is similar. Now one component of the kinematic sequence which has been determined to be a “power source” or “signature” of efficiency is the anterior/posterior tilt of the pelvis. Remember the body operates in 3 dimensions and power development for the rotary athlete does not only occur in a linear motion. If we look at additional graphs from 3 Dimensional Motion Analysis and review of what segments are doing, and what movements are occurring within an efficient pattern, we see some very interesting data points.

One of these data points is what the pelvis does during the downswing in golf, delivery in pitching, and from foot contact into impact with a hitter. The pelvis is obviously moving in multiple vectors and one of these vectors or patterns is a anterior to posterior pelvic tilt. Basically, these rotary athletes will move from an anterior to posterior pelvic position at impact or release. In other words the hips “tuck under” with these athletes. Let’s take a look at a graph example to allow a visual of this signature.

Pelvis Bend

In the world of motion analysis the anterior and posterior movement of the pelvis is termed “Pelvis Bend”. The pelvis bend graph above shows a slight anterior movement of the pelvis and then a very aggressive posterior tilt into impact, contact, or release. The data indicates this to be a “signature move” of power production and speed translation in these athletes. Basically if review of a 3 D Motion Analysis does not show this signature move in pelvis bend then we know the speed translation and power production is limited. Why is it being limited?

That is an entirely a different question, requiring a secondary set of assessments to determine and quantify. Though I can tell you this and we discussed it earlier in the article. Inefficiencies in the Kinematic Sequence and Pelvis Bend will fall into one of two buckets. Bucket one being physical dysfunctions and bucket two mechanical inefficiencies.

To summarize we now have the ability to quantify speed and power production within the rotary athlete. In this day and age we are no longer guessing about efficiency, speed translation, and power production. We now know how to quantify and determine the efficiencies, inefficiencies, where improvements may be made, what injuries may potentially exist within an athlete, and how to address athlete improvements from a scientific based platform.

About Performance Coach Sean Cochran: Sean Cochran, one of the most recognized performance coaches in sports today. A career spanning positions with 2 major league baseball organizations, over 12 years on the PGA Tour and work with top professionals including three-time Masters, PGA, and British Open Champion Phil Mickelson, future hall of fame Trevor Hoffman, and Cy Young award winner Jake Peavy provides Sean a proven track record of success.  He has been involved in the production of numerous performance videos and authored books including; Performance Golf Fitness, Complete Conditioning for Martial Arts, and Fit to Hit. He has been a presenter of educational seminars for numerous organizations including the world renown Titleist Performance Institute.

References

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