PowerPoint Presentation

Sangwoo Lee, Ron Davis, PhD, Cathy Sellers, and Larry Judge, PhD Research and Coaching Application for USA Seated Shot Put Paralympians

1Shot Put Project

With high Performance Director for U.S. Paralympic Track and Field 2Purpose of ProjectThe projection conditions (release height, speed, and angle) determine the throw distance.

Purpose Analyze the projection conditions of the athletes competed in the 2012 US Paralympic Trials (track and field)

Determine how each projection condition affects the distance thrown

Compare the projection conditions between male and female athletes

3Shot Put Motion

4MethodsParticipantsSixteen shot-put athletes 11 males and 5 females; disability categories F53-F58

Equipment 4 digital video cameras (60Hz)Calibration frame (221m)16 body pointsHand, wrist, elbow, shoulder for both sides of the body and right, left, anterior heads, sternum, and shotKwon3D & Matlab

5Methods (cont.)

Experimental setting

6Methods (cont.)Data reduction and processing

First synchronized to the instant of shot release

Digitized to obtain the stick figures and analyze the motions

Reconstructed from the image coordinates of the digitized points and camera calibration information using the DLT method (Abdel-Aziz & Karara, 1971)

Filtered using a zero phase-lag fourth-order Butterworth low-pass filter

A cutoff frequency: 6Hz

7Methods (cont.)

8Methods (cont.)Data analysis

: Release angleH: Release heightV: Release speedYZX9Methods (cont.)Data analysisRelease angle:

10Methods (cont.)Data analysis

Release speed: The resultant linear velocity of a shot at shot release

Release height: The difference in height from the land to the vertical position of hand at shot release.

Distance thrown from the official recordsThe best 3 attempts of 6 attempts

11Methods (cont.)Statistical analysis

Multiple regression (enter method)IVs: Release angle, release speed, and release height DV: Distance thrown

Two-Way Factorial MANOVA between subjectsIVs: Gender and classDVs: Release angle, release speed, release height, and throwing distance

12ResultsCorrelations of distance thrown and IVs using Pearsons correlation

VariableCorrelation with the distance thrownp valueRelease angle.415.002Release speed.897p< .001Release height.271.031ModerateStrongWeak13ResultsMultiple regression model coefficients

Dependent variables: Distance thrownModelCoefficient (B)SEStandardized Coefficient ()tp(Constant)-8.1643.219-2.536.015Release angle.174.050.2103.467.001Release speed1.626.119.87913.694P < .001Release height-2.1961.476-.094-1.488.144Note: R = .922, R2 = .850, Adjusted R2 = .840Distance thrown = -8.164 + (.174*release angle) + (1.626*release speed)14Disability CategoryF53: Have normal shoulders, elbows, and wrists, with mild limitation of hand function. No trunk or leg function.

F54: Have normal arm and hand function. Have no trunk or leg function.

F55: Have normal arm and hand function. In relation to the trunk, can extend the spine in an upward direction and can rotate the spine. No leg function.

F56: Have normal arm and hand function. Can extend the trunk upward, can rotate, and can move backward and forward in a sitting position. Have some leg function.

F57: Have normal arm and hand function. Can move the trunk in an upward direction, can rotate, can move backward and forward, and can move side to side. Have an increase in leg function in comparison with F56.

F58: Have normal arm and hand function. Have normal trunk function. Have more leg function than F57. 15ResultsTwo-way Factorial MANOVA results

F53F54F55F56F57F58Sig. effectsRelease angle ()M29.22 2.1932.36 6.5737.79 3.3837.04 2.11 34.9 3.637.02 1.28GENDERCLASSF-26.8 3.31-29.33 0.6832.13 4.81-Release speed (m/s)M7.14 .0.56.78 0.468.25 0.185.48 0.178.03 0.259.86 0.29GENDER CLASSF-5.89 0.54-8.32 0.158.47 0.2-Release height (m)M1.95 0.011.81 0.071.83 0.111.72 0.021.95 0.071.81 0.13GENDER CLASSF-1.78 0.03-1.96 0.011.98 0.03-Distance thrown (m)M7.67 0.066.48 0.410.16 0.416.31 0.099.26 0.8612.82 1.33GENDER CLASSF-5.36 0.66-9.22 0.118.75 0.09-16Overall ResultsRelease speed > release angle > and release height

Differences in projection conditions Among classes Between male and females

17Discussion

The effect of release speed and release angle on the throwing distance of a shot with a constant release height(Linthorne, 2001)Optimum angle: 37 Male Female Change in release speed > Change in release angle 18ConclusionRelease speed is the most important projection condition

Differences in projection conditions Among classes Between male and females

So what??

ApplicationAthletes should increase release speed as high as possible and release angle as close to 37 as possible AT THE SAME TIME

The projection conditions are NOT INDEPENDENT (Hay, 1993; Dyson, 1986; Hubbard, 1988; de Mestre, 1990; de Mestre et al., 1998; Maheras, 1998)Release speed decreases linearly with increasing release angle

The release angles could be their optimum angles Due to the nature of their physical structure and muscular strength

The change in release speed > the change in release angle

Throwing with a high release speed is more important to performance than throwing at the optimum release angle21TWU Research Team from Biomechanics and Adapted Physical Activity

Questions?22