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Training The Overhead Athlete
THE LATEST SPORT SCIENCE & MEDICINE UPDATES
MARK KOVACS, PHD, FACSM, CSCS*D@MKOVACSPHD
WWW.MARK-KOVACS.COM
DIRECTOR, LIFE SPORT SCIENCE INSTITUTE
ASSOCIATE PROFESSOR, SPORT HEALTH SCIENCE DEPARTMENT, LIFE UNIVERSITY
KOVACSINSTITUTE.COM
Baseball
Dines et al. The Kinetic Chain of Overhead
Athletics: A Systematic Reviw of Biomechanics
and Associated Pathoanatomy. Hospital
for Special Surgery
The Shoulder & Elbow Are Many Times Not The Cause of The Problem… Many Times Shoulder & Elbow Pain Are The Result
Elbow Position From Start Till Contact
Typical Muscle Sequencing Pattern for a Simple Right Arm Elevation Movement
Deactivation of the left soleus
Activation of left semitendinosisand glute max
Activation of the right TFL and rectus femoris
Activation of right erector spinae
Initial deltoid activity
Baseball Pitch Pelvis vs Thorax
Nissen et al. MSSE 2007
This image represents a right handed picture, where the top image is the hips, and the bottom image is the torso (right and left shoulder joint centers of rotation).
Understanding the Overhead Athlete Pitcher rotates his pelvis - then upper trunk to face the
target - while abducted arm externally rotates at the shoulder.
Peak values of shoulder internal rotation torque & elbow varus torque are produced at/near maximum external rotation to decelerate shoulder external rotation, prevent elbow valgus opening, and initiate shoulder internal rotation.
Tension in the ulnar collateral ligament (UCL) absorbs about half the maximum varus torque in this position
Fleisig, G.S. and Andrews, J.R. (2015) Prevention of elbow injuries in youth baseball pitchers. Sports Health. 4 (5), 419-424
Understanding the Overhead Athlete
Research has shown similar motions and timing between youth and adult pitchers but with increased elbow and shoulder velocities, forces, and torques at higher levels.
Pitchers at the youth level also have greater inconsistency in their biomechanics from pitch to pitch. Like an adult pitcher, the young pitcher swings his arms apart and up during the leg stride
Fleisig, G.S. and Andrews, J.R. (2015) Prevention of elbow injuries in youth baseball pitchers. Sports Health. 4 (5), 419-424
Understanding the Overhead Athlete
At the time of front foot contact, the throwing shoulder is abducted about 90°, and the elbow is flexed about 80°.
Elbow flexion at the time of maximum shoulder external rotation varies greatly among studies, reportedly from 57° to 100°.
From this cocked position, elbow flexion and shoulder internal rotation are initiated. Peak elbow extension velocity of approximately 2000 degrees per second is achieved shortly before ball release.
Fleisig, G.S. and Andrews, J.R. (2015) Prevention of elbow injuries in youth baseball pitchers. Sports Health. 4 (5), 419-424
Understanding the Overhead Athlete
Improper pitching mechanics can lead to increased varus, late arm rotation (measured as insufficient shoulder external rotation at the instant of front foot contact), excessive shoulder external rotation, excessive elbow flexion, and improper shoulder abduction and trunk tilt.
Correcting flaws in pitching mechanics can reduce the stress on the elbow, reduce the stress on the shoulder, and/or increase ball velocity. Improving biomechanics can increase a pitcher’s chance of staying healthy and succeeding.
Fleisig, G.S. and Andrews, J.R. (2015) Prevention of elbow injuries in youth baseball pitchers. Sports Health. 4 (5), 419-424
The misunderstood CURVEBALLDun S, Loftice J, Fleisig GS, Kingsley D, Andrews JR. A biomechanical comparison of youth baseball pitches: is the curveball potentially harmful? Am J Sports Med. 2008;36:686-692.
29 youth pitchers (11 to 14 years old) who threw fastball, changeup, and curveball pitches. There was no screening of curveball “good” or “bad” mechanics.
All who threw fastballs, changeups, and curveballs were included. As expected, the curveball had greater forearm supination than the fastball. However, elbow varus torque was significantly less in the curveball (31.6 ± 15.2 Nm) than in the fastball (34.8 ± 15.4 Nm).
Nissen CW, Westwell M, Ounpuu S, et al. Adolescent baseball pitching technique: a detailed three-dimensional biomechanical analysis. Med Sci Sports Exerc. 2007;39:1347-1357.
High school pitchers (14 to 18 years) found significantly less varus torque in the curveball (54.1 ± 16.1 Nm) than fastball (59.6 ± 16.3 Nm).
Fleisig GS, Kingsley DS, Loftice JW, et al. Kinetic comparison among the fastball, curveball, change-up, and slider in collegiate baseball pitchers. Am J Sports Med. 2006;34:423-430.
Evaluated collegiate pitchers and found no significant difference in varus torque between fastballs and curveballs. Previous cadaveric research has shown that supination does not affect tension in the UCL during elbow varus torque.
No consistent data to show curveballs before the age of 13 lead to greater surgery rates. Multiple studies have shown no difference -
Fleisig, G.S. and Andrews, J.R. (2015) Prevention of elbow injuries in youth baseball pitchers. Sports Health. 4 (5), 419-424
Curveballs
Curveballs at a young age DO NOT/MAY NOT pose a greater threat to young pitchers.
Differences among fastball, curveball, and change-up pitching biomechanics across various levels of baseball. Fleisig, G.S., Laughlin, W.A., Aune, K.T., Cain, E.L., Dugas, J.R. and Andrews, J.R. Sports Biomechanics 15 (2). 2,2016
Ball Velocity Alone Likely Not The Only Reason For Pain/Injury
Although a weak positive correlation was present between ball velocity & shoulder-distraction force, no significant association was seen between ball velocity and elbow-valgus torque or shoulder external-rotation torque. Therefore, other factors, such as improper pitching mechanics, may contribute more to increases in joint kinetics than peak ball velocity.
Post et al (2015). Correlation of shoulder and elbow kinetics with ball velocity in collegiate baseball pitchers. Journal of Athletic Training, 50(6), 629-633
However, most other studies have shown a rather strong link with pitching velocities and UCL issues .
10 Evidence Based Recommendations for Youth PitcherWatch and respond to signs of fatigue (eg, decreased ball velocity, decreased accuracy, upright trunk during pitching, dropped elbow during pitching, or increased time between pitches). If a youth pitcher complains of fatigue or looks fatigued, rest is recommended.
No overhead throwing of any kind for at least 2 to 3 months per year (4 months is preferred). No competitive baseball pitching for at least 4 months per year.
Do not pitch more than 100 innings (in games) in any calendar year.
Follow limits for pitch counts and days rest.
Avoid pitching on multiple teams with overlapping seasons.
Fleisig, G.S. and Andrews, J.R. (2015) Prevention of elbow injuries in youth baseball pitchers. Sports Health. 4 (5), 419-424
10 Evidence Based Recommendations for Youth Pitcher
Learn good throwing mechanics as soon as possible. The first steps should be (1) basic throwing, (2) fastball pitching, (3) changeup pitching.
Avoid using radar guns.
A pitcher should not also be a catcher for his team. The pitcher-catcher combination results in many throws and may increase the risk of injury.
If a pitcher complains of pain in his elbow or shoulder, discontinue pitching until evaluated by a sports medicine professional.
Inspire youth pitchers to have fun playing baseball and other sports. Participation and enjoyment of various physical activities will increase the youth’s athleticism and interest in sports.
Fleisig, G.S. and Andrews, J.R. (2015) Prevention of elbow injuries in youth baseball pitchers. Sports Health. 4 (5), 419-424
Significant predictors of UCL reconstruction in MLB pitchers1) Fewer days between consecutive
games, 2) A smaller repertoire of pitch
variations, 3) A less pronounced horizontal
release location,4) A higher mean pitch count per
game,5) A smaller stature, 6) A higher mean pitch speed
significantly increased the likelihood of UCL reconstruction at the MLB level.
These data imply that recovery after pitching bouts may be just as, if not more, critical to injury prevention as pitch counts.
Whiteside et al (2016). Predictors of Ulnar Collateral Ligament Reconstruction in Major League Baseball Pitchers. Am J Sports Med
According to this data, arm slots closer tothe midline of the body (ie, closer to ‘‘overhead’’) were more injurious.
Nearly one extra day of recovery between starts shows less surgeries
Predictors of UCL Injuries in MLB
1) A higher mean pitch count per game,2) A smaller stature, 3) A higher mean pitch speed significantly increased the likelihood of UCL reconstruction at th
MLB level. These data imply that recovery after pitching bouts may be just as, if not more, critical to injury prevention as pitch counts.
Whiteside et al (2016). Predictors of Ulnar Collateral Ligament Reconstruction in Major League Baseball Pitchers. Am J Sports Med
What Baseball Can Learn From Tennis
Preparation Phase
From the first sign of movement until maximal external rotation of the shoulder. Which coincides at the point when the tip of the racket head points toward the ground.
1. Start
2. Release From the start stage (ball and racket at rest) until the ball is released from the non-serving hand
3. Loading From the release stage until a fully loaded lower body position. This position coincides with the elbows lowest vertical position and also maximum knee flexion
4. Cocking From the end of the loading stage until maximal shoulder external rotation coinciding with the tip of the racket head pointing toward the ground
Acceleration Phase
Begins from maximal external rotation of the shoulder until the end of ball contact.
5. AccelerationFrom end of the cocking stage until contact
6. ContactThe very short period where ball and racket impact
Follow-Through
Phase
Begins immediately post ball contact and continues through the end of the service motion.
7. Deceleration Following contact until the end of upper and lower body deceleration of the serve
8. Finish
The short period at the end of deceleration and before the initial movement to prepare for the next stroke
THREE PHASES EIGHT STAGES
Preparation PhaseFrom the first sign of movement until maximal external rotation of the shoulder. Which coincides at the point when the tip of the racket head points toward the ground.
STAGE 1. Start
Preparation PhaseFrom the first sign of movement until maximal external rotation of the shoulder. Which coincides at the point when the tip of the racket head points toward the ground.
STAGE 2. ReleaseFrom the start stage (ball and racket at rest) until the ball is released from the non-serving hand
Preparation PhaseFrom the first sign of movement until maximal external rotation of the shoulder. Which coincides at the point when the tip of the racket head points toward the ground.
Stage 3. LoadingFrom the release stage until a fully loaded lower body position. This position coincides with the elbows lowest vertical position and also maximum knee flexion
HYPERANGULATION
Preparation PhaseFrom the first sign of movement until maximal external rotation of the shoulder. Which coincides at the point when the tip of the racket head points toward the ground.
Stage 4. CockingFrom the end of the loading stage until maximal shoulder external rotation coinciding with the tip of the racket head pointing toward the ground
Stage 5. Acceleration
From end of the cocking stage until contact
Acceleration Phase
Begins from maximal external rotation of the shoulder until the end of ball contact.
Acceleration Phase
Begins from maximal external rotation of the shoulder until the end of ball contact.
Stage 6. Contact
The very short period where ball and racket impact
Follow-Through Phase
Begins immediately post ball contact and continues through the end of the service motion.
Stage 7. DecelerationFollowing contact until the end of upper and lower body deceleration of the serve
Long Axis Rotation
Follow-Through Phase
Begins immediately post ball contact and continues through the end of the service motion.
Stage 8. Finish
The short period at the end of deceleration and before the initial movement to prepare for the next stroke
Typical Issues
Internal ShoulderRotation Tightness
Tight Internal Right Shoulder Rotators
Sleeper Stretch Assessment (i.e. GIRD Self-Assessment)
Dominant ArmNon-Dominant Arm
Hip Range of Motion
Ankle Dorsiflexion Assessment< 10cm INCREASED RISK OF HAMSTRING INJURY in Australian Rules Football Athletes (Gabbe et al SJMSS, 2006)
> 14cm REDUCED RISK OF SHOULDER INJURY in Cricket Fast Bowlers (Dennis et al, BJSM 2008)
Take Care of The Details
Use Evidence TO Guide Your Training and Treatment Plans
Focus on The Kinetic Chain Lower Body FirstStability Before Strength Test, Train, Treat, Measure - REPEAT
Questions
Mark Kovacs, PhD, FACSM, CSCS*D@mkovacsphd
www.mark-Kovacs.comDirector, Life Sport Science institute
Associate professor,Sport health science department, life university