# Bat Flexibility- HHP 364

2 Oct 2015
1 sur 17

### Bat Flexibility- HHP 364

• 1. Dan McKinney HHP 364
• 2.  “Some marketing materials say that handle flex improves performance because the "whip action" allows the bat to uncoil and release energy stored during the swing and increases the bat speed at the moment of impact” (Russell, 2007).  “Marketing materials for stiff handled bats claim that stiffer handles allow the trampoline effect in the barrel to be more effective thus improving batted-ball speed” (Russell,2007). Easton Claims: “It’s trying to improve the way the handles of its bats flex to increase the size of the sweet spot—the area on the barrel that delivers the most power—so hitters can rap singles and doubles even if they don’t make solid contact” (Greene, 2004).  Louisville Slugger Claims: “Louisville Slugger’s 2009 line is built with stiffer handles and larger sweet spots in mind. The TPX material says that a stiff handle creates more barrel flex, thus increasing the “trampoline effect” and creating more energy transfer” (Conrad, 2008).
• 3. VIDEO! http://www.bing.com/videos/watch/video/flexible- handled-baseball- bats/a451f321d19ee1ce2e7ba451f321d19ee1ce2e7b- 320627409871?q=flexible%20baseball%20bats&FROM= LKVR5&GT1=LKVR5&FORM=LKVR
• 4.  Velocity: The rate of speed calculated in Miles Per Hour.  Coefficient of Restitution/Trampoline Effect: The coefficient of restitution is a measure of the elasticity of the collision between ball and bat. Elasticity is a measure of how much bounce there is, or in other words, how much of the kinetic energy of the colliding objects before the collision remains as kinetic energy of the objects after the collision. Louisville Slugger Strategy  Whipping Action: Handle flex allows energy stored in the whip action during the swing to be released at impact in order to provide a greater batted-ball speed. Easton Strategy  Hitting: The sequential unlocking of body parts to maximize bat speed at the point of contact.
• 5.  Ha: The most flexible handled bat (65), will create the highest exit velocity of a batted ball off of a stationary hitting tee!  Ho: There is no significant difference of the exit velocity from different flexible handled bats.
• 6.  Flexible rating of 3 different Easton Aluminum Collegiate Baseball Bats  The flexibility of bat handles range from 65-100.  100= Stiffest handle  65= Maximum flexibility  Test was administered using a 65, 90, and 100 flexible handled rating Dependent Variable  Exit velocity speed of a baseball off of a stationary hitting tee  5 swings per participant with each bat (65, 90, 100)  8 total participants  120 total swings
• 7.  Participants  8 MSU-Billings University Baseball Players  College aged Freshman-Seniors  18-24 years old  Randomly Assigned  Trained Collegiate Baseball Athletes
• 8. Apparatus/Materials  Stalker Radar Gun- Used to see velocity/speed of the baseball  5 Wilson A1001-Red Cushioned Cork Center: Premium Leather (Brand New Pearls)  ATEC Tee- Standardized and Stationary  Batting Cage/Net- Located in Lower Gym: MSU- Billings Campus  8 Participants
• 9. Instruments Continued…… Easton Aluminum Bats  Model-Length-Ounces-Barrel Diameter-Flex Yellow BSV2 33 in 30 oz. 2 5/8 in Red BZN1 33 in 30 oz. 2 5/8 in Green BV2 33 in 30 oz. 2 5/8 in Yellow: Flex- 65 Flexible Handle Rating Red :Flex- 90 Flexible Handle Rating Green: Flex- 100 Flexible Handle Rating
• 11. Procedures Participant- Parallel to the tee and perpendicular to the net. http://www.bing.com/videos/watch/video/baseball-hitting-instructional-videos-tee- drill/6d2a55979e1869998a216d2a55979e1869998a21- 309014495480?q=baseball%20tee&FROM=LKVR5&GT1=LKVR5&FORM=LKVR34
• 12. Procedures Continued….  Participants randomly selected. 8 total participants  Tee placed in front of net  Each participant hit 5 Pearls with each bat  KEY/Instruction: Hit the ball as hard as possible directly into the net and directly at the radar gun  The exit velocity of the baseball was recorded after each swing in miles per hour.
• 13.  True Experimental Design-Groups were randomly formed, and all subjects were equivalent at the beginning of the research.  Randomized Groups R T O  ANOVA- Analysis of Variance: Test that allows the evaluation of the null hypothesis between two or more group means.
• 14. 0 10 20 30 40 50 60 70 80 90 100 1 2 3 4 5 6 7 8 yellow green red Subjects E x i t V e l o c i t y 0 10 20 30 40 50 60 70 80 90 100 1 2 3 4 5 6 7 8 yellow green red Subjects E x i t V e l o c i t y Yellow Bat (65 Flex) Mean: 84.1 MPH Red Bat (90 Flex) Mean: 84.4 MPH Green Bat (100 Flex) Mean: 85.4 MPH
• 15.  F Value= 0.15  P Value=0.86  DF (Degree of Freedom) between groups=2  Error= 14  Critical Value=3.74  No Significant Difference!  86% Chance  Ultimately have to Accept Null Hypothesis ◦ .15<3.74 Critical F Value ◦ Pg-405: Statistical Tables
• 16.  History-Fatigue of Participants  Health of each bat- Dents and overuse  Health of Athletes- Rehab?  Expectations of Athlete/Researcher
• 17.  Money Talks- Maybe it is the operator and not the tool!  Thesis Ideas