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Manipulation of Postactivation Potentiation vs. the Use of a Weighted Bat
Matt SalacienskiAusten HuttonDavid Kimmich
Purpose
The purpose of this study is to whether or not the idea of postactivation potentiation can be utilized by collegiate baseball players prior to batting to
increase their swing velocity.
Background
It takes less than half a second for a 90 mph fastball to reach the home plate.
A faster swing = Competitive advantage for the hitter
Traditionally, hitters tend to use weighted “donuts”, or multiple bats to achieve this
Background
Montoya et al. conducted a study in which warming up with a weighted bat was shown to actually decrease swing velocity
“Kinetic Link Theory”
This refers to the transfer of momentum beginning in the lower body, up through hips and torso, and ending with the upper body.
http://www.youtube.com/watch?v=DtniXJk-mhE&feature=related
Postactivation Potentiation (PAP)
This suggests that maximal contraction of certain muscles prior to performing an explosive action can enhance overall power output during that action
Two theories exist as to why this occurs:
Increased phosphorylation of myosin light chains
Excitation of the Hoffman Reflex (H-Reflex)
Complex Training
Training protocol most commonly used in manipulating PAP
Combines heavy resistance exercises with plyometric exercises
Targets same muscle group to help transfer strength gains into power
Enhances nervous system involvement
Complex Training
Farup and Sorenson (2010)
1-RM bench press followed by a bench throw
Hrysmallis and Kidgell (2001)
5-RM bench press followed by explosive push-ups
Effect of Training Status
Chiu et al. (2003)
Heavy load squats followed by jump squats
Found that athletically-trained individuals are more apt to elicit PAP than are recreationally-active individuals
More resistant to fatigue
Methods
Interest: Effect of heavy resistance training prior to swing
10 DIII Collegiate Baseball Players Similar weight and stature (levers)
Only those who make plate appearances
This study will have been approved by the Institutional Review Board
All subjects have read and signed an informed consent
Methods Cont.
Acute Study
No training program implemented
Focus on muscle activation
Pre-Test
1RM for bench and squat
Needed for 1RM % during exercises
Methods Cont.
3 days of testing
Begin with dynamic warm-up (10 mins)
First 2 Days: Complex Training
Day 1: Bench paired with medicine ball power drops
3 sets of 3 reps at 80-90% 1RM (2 min rest)
After 3rd set, 1 min rest before power drops
3 min rest before taking 5 swings with normal weighted bat
Methods Cont.
Complex Training Cont.
Day 2: Squat paired with depth jumps
Load, volume, # of sets same as day 1
Depth Jumps: 36 inch box
Same rest periods
Day 3: Weighted Bat
5-8 swings with weighted bat/donut
Followed by velocity test
Technology
Detects X and Y velocity to give slope
Pick point on bat
Lower mph: v = rω
Higher radius = higher speed
Lower radius = lower speed
Statistics
Independent Variable
Mode of exercise/warm-up
○ Upper Body
○ Lower Body
○ Weighted Bat
Dependent Variable
Bat Swing Velocity
○ Comparing speed of swing after implementing 3 modes of warm-up
Statistical Analyses
Test
One-way ANOVA
○ 1 group
○ 3 means being compared
○ Shows difference between velocity means
Tukey Post-Hoc
○ Shows where difference is located
P-Value ≤ 0.05
Expected Results
May see a loss in velocity after weighted bat warm-up
Any increase in velocity: lower body exercises
Baseball focuses on lower body strength (anaerobic)
Data Collection
Subject 1 Subject2
Subject 3
Subject 4
Subject 5
Base 24.5 47.9 31.0 24.3 24.5
Weighted Bat
25.2 36.7 33.6 32.9 24.9
Lower-Body
35.2 67.7 31.5 58.5 36.4
Upper-Body
30.8 40.7 34.3 55.1 31.7
Data Collection
Significant at the 0.05 alpha level
Unfortunately, data collection produced error
Hand motion
Height
Level swing
Point analysis
N value was very low
Data Collection
Thank you Dr. Mendel and Dr. Ekey