Kinematic Sequence
- Eclipse Wellness
- Mar 5, 2022
- 7 min read
Updated: Jul 8, 2023
The kinematic sequence refers to the order in which various body parts accelerate and decelerate through a motion. It originally gained popularity in golf, particularly with the Titleist Performance Institute. Golf is a sport that has fully embraced technology and innovation, long before baseball and other sports. Golf is also an easier sport to analyze because there are less moving parts. The ball sits on a tee and therefore all the processes are repeatable and the athlete does not have to react to a moving ball like in baseball.
We have always thought that power is created by your entire body, and researchers set out to prove it for golf. Even if you do not know anything about golf, you can tell when someone strikes the ball easily, or when they look like they have never hit a golf ball in their life. True professionals know how to maximize every aspect of their body to create torque and power for ball strike. Amateur players will attempt to “muscle up” or use their upper body without tapping into the potential of their entire kinetic chain, which refers to the connection of your body.
The image above shows the 4 main parts of the kinematic sequence in golfers. Power starts from your hips, goes to your torso, then your arms, until finally the club impacts the power onto the ball. This seems intuitive, but it is important to understand to allow for further concepts.
Acceleration is calculated based on how fast something changes velocity. If your car accelerates from 0 to 60 mph in 10 seconds, that is much faster acceleration than if it goes from 0 to 60 mph in 10 minutes. We want rapid acceleration in a golf swing because force is based on mass times acceleration. Higher acceleration leads to a higher force which means a further driving distance!
This image shows a good kinematic sequence for a golfer, courtesy of K-Vest. The colors match the image above and you can see the order of acceleration is ideal: hips, torso, arms, and then club. You can also see that there is a wave effect where each segment is higher than the last. This is showing the growth in power and force with each subsequent segment.
Another important concept demonstrated in the above graph is deceleration. Declaration refers to the stopping of an object or segment, and it helps explain the wave phenomenon that is seen above. Imagine you are shooting a rubber band. You hold it in one hand and draw it back with the other. You let go with the back hand before you do the front hand. Imagine if you let go with both hands at the same time. The rubber band would snap together but it would not go anywhere. The bracing of the front hand allows the power transfer to continue. Now imagine that you are throwing a punch. If you want to punch as hard as you can, you want to actually stop your hips as you are swinging. This will create more momentum to transfer into your fist.
The boxer in red has planted his left foot and it serves as an anchor while punching. He is not going to continue to spin after punching, he will almost rebound backwards from the deceleration force traveling up from his hips. If he continued to rotate his hips with the punch, there would be no separation and he would actually lose force.
The kinematic sequence can be somewhat confusing, but it is an important concept to understand. Unfortunately, I am by no means a golf expert, however, I am a baseball expert. Let’s take a look at how kinematic sequence applies to baseball.
Baseball Kinematic Sequence
Baseball is actually very similar to golf in regards to the motions required in the sport. Rotation is the primary driver of force, with some linear momentum added. Obviously, a moving ball complicates some parts of the kinematic sequence, but the ideas are the same. Pitching is also slightly different based on the mechanics, but at its root, you can apply a lot of what we described above to pitching and hitting.
Baseball Kinematic Sequence Pitching
The image above illustrates the kinematic sequence for pitching. The four parts are slightly different since there is no club, but the concepts are similar. Energy should pass from the pelvis to the torso to the shoulder, and finally to the hand. Foot plant is an important part of timing because it helps cue deceleration. Imagine trying to throw a pitch with your lead foot in the air. You would lose most of your power because you lack a base from which to decelerate. The planting of the foot and subsequent lead leg block uses the ground to anchor your pelvis and transfer energy. Often, pitchers make the mistake of trying to throw too soon and they lose the valuable support that the ground provides. This is a massive energy leak.
Utilizing technology such as the K-Vest can make the kinematic sequence readily apparent and provide immediate feedback to the athlete and coach. Pitching mechanics are obviously important, but everyone is unique in how they move. If you watch a Major League Baseball game, you will see drastically different pitching motions. However, the core kinematic sequence of successful pitchers is the same. There may be a lot of moving parts, but the timing should include energy flowing from the pelvis to the torso to the shoulder to the hand.
Baseball Kinematic Sequence Hitting
The image above shows the kinematic sequence for hitting. Once again it is slightly different from pitching, with the upper arm replacing the shoulder. You can still notice the accelerations and decelerations follow a predictable pattern resulting in a rising wave of power. Hitting is more analogous to golf, as the swing characteristics are similar. It is important to note that very few hitters or pitchers have “perfect” kinematic sequences and that is to be expected. Most players have something to improve on and this gives you a roadmap of what that thing is.
Baseball Kinematic Sequence Physical Therapy
The question I often receive about the kinematic sequence is simple: why do you care? I am, afterall, a doctor of physical therapy and certified strength and conditioning specialist. I am not the one taking the athlete on the mound or into the batting cage and breaking down his mechanics. However, it is important to understand the goals of an athlete in order to adequately rehab and train them. If I have an idea of what the athlete and coach want to achieve from a physical perspective, it gives me a map of where to go. Too often, physical therapists operate blindly and look to improve shoulder strength or hip mobility simply based on what they see on the table. Truly precise performance physical therapy should consider the athlete as a whole and what improvements can be made in their performance.
A study by Scaborough, et al. showed that kinematic sequence played a role in shoulder and elbow torque in baseball pitchers. This has important implications for physical therapy, particularly if you are working with the shoulder or elbow of a pitcher. Rehab involves a time of relative rest, meaning you want to create less stress on the injured area to allow healing to occur. However, it is important to maintain as much activity as possible to prevent atrophy and deconditioning. Too often, medical providers will prescribe 4-6 weeks of no throwing to heal tissue. This can provide healing, but then it requires a couple of months to build back up workload that was lost during the time without throwing. If we can shift the stresses of pitching instead of abandoning them entirely, we can allow for relative rest while still providing some work for the arm.
Understanding the kinematic sequence allows for the shifting of stress. If I examine a pitcher with shoulder or elbow pain, I will do a full body assessment. If I find that his hip mobility in the front leg is limited in internal rotation, then I can ask further questions. Limited internal rotation prevents efficient deceleration of the pelvis, which limits power up the chain. This can decrease output and it can force stress in other areas to compensate. If we are able to improve hip mobility of the athlete, this can take stress off of the shoulder. Throwing volume should still be monitored, but it could lead to a quicker recovery and return to play which may be safer in the long term.
The above scenario is close to the ideal, but true understanding of the athlete typically involves the coach or athlete discussing his movement patterns. Athletes eventually reach the point where they understand their bodies best, but coaches may also provide a valuable voice. Even if they have not evaluated the kinematic sequence with equipment such as K-Vest, they may have valuable insights. If a pitcher struggles with throwing a breaking ball down in the zone, he may be experiencing limited hip internal rotation that prevents him from getting through the pitch. This can also be linked to decreased velocity on a fastball and greater stress on the arm. A discussion with a coach or athlete can often reveal these details, even if they were unaware of them. Sometimes the issue is not mechanics, but rather physical capabilities. The best pitching coach in the world can only have so much success if the pitcher has a tight hip or a weak shoulder.
In summary, it is important to have a team-based approach for an athlete dealing with an injury or looking to improve performance. Healthcare visits are unfortunately becoming shorter and shorter with less dialogue to analyze patterns and get to the root cause of issues. We created Eclipse because we wanted to spend more time with clients to allow for thorough assessments and receiving input from coaches. Taking the time to discuss performance with clients is important along with having the understanding of their goals and needs on the field during competition.
As always, if you are suffering from pain, nerve symptoms (numbness, tingling, or weakness), or anything else significant, please see a healthcare provider. This blog is meant to be educational and is not a substitute for medical advice.
Hopefully you learned something about the kinematic sequence and how it relates to rehabilitation, training, and performance. If you found this blog helpful, please share it with someone. We hope to continue to grow and help people better understand how our bodies move and work. If you are in the Sterling, Virginia area and would like to work with me or you have any questions, please email me at danny@eclipsewellnessnova.com or follow me on Instagram or Twitter @drdannydpt.
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