Kansas State University Biomechanics Lab Research in Biomechanics at KSU by Larry Noble, Specializing in Biomechanics of Exercise and Sport Courses I teach

Kansas State University Biomechanics Lab

Research in Biomechanics at KSUby Larry Noble, Specializing in Biomechanics of Exercise and Sport

•Courses I teach•Laboratory capabilities•Examples of master’s theses done in our biomechanics lab•Brief review of recent study on bat design•Ongoing research in our biomechanics lab


Courses I Teach

PKIN 330 BiomechanicsPKIN 630 Design and Analysis of Exercise and Sport EquipmentPKIN 718 Videographic and Cinematographic Analysis of Human MotionPKIN 825 Mechanical Analysis of Human Movement


Kin 825 Course Topics• Definition and scope of biomechanics • Kinetics review• Anthropometry, Total Body COM• Observing and Analyzing Human movement• Gait Analysis• Methods and tools for biomechanical analysis• Force Platform Demo• Biomechanics of sport• Biomechanics of exercise • Injury Prevention• Electromyography• EMG demonstration lab• Biomechanics of bone• Ergonomics• Aging• Journal article presentations• Journal article & term paper presentations• Term paper presentations


Biomechanics Laboratory CapabilitiesPCinematographic equipment (up to 500 fps)

Cameras, tripods, lights, marking suppliesAnalysis equipment and softwarePVideographic equipment

Digital video cameras (up to 240 fps)SVHS cameras, VCRs, lights, marking suppliesEquipment and software for 3D analysisPElectromyography equipmentAPAS 4-channel unit with preamplifiesPLoad measurement equipmentAMTI force platform, load cells, load beams, accelerometers


Examples of Theses From Our LabPSpragg, Carolyn A. (1986) A comparison of selected mechanical factors in male baseball and female fast pitch softball batting.PHarris, Chad. (1987) Kinematic analysis of the tying phase of calf roping.PYu, Bing. (1988) Determination of the appropriate cutoff frequency in the digital filter data smoothing procedure.PRinger, Geoffrey W. (1992) The effects of exterior loading on selected mechanical and vibrational characteristics of tennis rackets.PPonte, J.M. (1993) A comparison of load characteristics associated with pogo stick bounding and jumping rope.PAllen, G. Christy L. (1994) The effect of preventative drills on stability of the knee in female basketball players.PRoberts, Richard. (1996) The Effects of Hip Flexion on Lumbar Hyperextension and Iemg of Hip Flexors During the Bench Press.PHarper, Denise. (1997) Ground Reaction Force Patterns at Different Velocities using Running Shoes and Combat Boots


Theses (cont=d)

•Dudley, Chris. A mechanical analysis of the running step technique in volleyball. (1998)•Mendoza, Jennifer. The back handspring on the balance beam: a kinematic comparison of two techniques.(1998)•Benson, Tim. The effect of mound height on pitching kinematics.(1999)•Stroede, Claire. The effect of tennis racket string vibration dampers on racket handle vibrations and discomfort following impacts. (1999)•Hildenbrand, Kasee. Abdominal muscle activity while performing trunk flexion exercises using the Abroller, Abslide, Fit-ball, and conventionally performed trunk curls. (2001)•Harms, Nolan. The Relative Effects of Warmup using Bats of Varying Weights on Bat Velocity and Segmental Movements. (2003)


Focus of recent bat research – to evaluate efficacy of new bat design features

• Aluminum bats first appeared around 1970

• Since 1980 materials with higher strength/mass ratios have emerged• The plethora of recent

innovations are causing concern by softball & baseball governing bodies & are confusing consumers

• How do we evaluate these innovations (or gimmicks)?


Bat Flexibility Field Test• First, a controlled blind field test involving 6 different bat flexibilities

with 32 elite softball players was funded by a bat manufacturer• Results indicated that these hyper-flexible bats resulted in greater post-

impact velocity and were preferred by elite slow-pitch hitters over stiffer bats (Noble, Tech Rep to Easton Aluminum 1998)• An examination of bat bending characteristics during the swing followed this study (Noble, Proc ISBS 2001)


Does the “springboard”effect, or diving board mode, exist?

Is it possible for hitters to take advantage of it?


Procedures


Procedures


Results - Waveform Characteristics in Horizontal Direction


Bat Vibrations During Swing & Impact

-4

-3

-2

-1

0

1

2

3

4

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Time (s)

Str

ain

(v

)

Horiz DirVert DirMagnitudeHoriz DirVert DirMagnitude

Begin Swing 233ms PC

Peak 41 ms PC

Horiz Pk 38 ms PC



Begin swing 183 ms PC

Peak bending and peak torque ~ 50 ms PC

Impact – bat still bentback approx 20% of max


Bat Vibrations During Swing and Impact: Conclusions

• During the swing, the bat bends back and stores elastic energy that is released during impact

• Thus, a more flexible bat would appear to be more effective if the ball impacts at the sweet spot

• During impact, the bat behaves as a free-free body• A stiffer bat would appear to be more effective if the ball

does not impact at the sweet spot.• Perhaps a stiff bat is better for baseball and fast-pitch

softball and a flexible bat is better for slow-pitch softball


Ongoing Research

• Brett Linbgo – working on prooposal to examine resistive exercise methods using videography and electromyography

• Brian Gehlen – working on proposal to examine squat technique

• Lab – proposal to evaluate the performance properties and perceptions of use of laminated wood flooring.


Questions?

Documents

Kansas State University Biomechanics Lab Research in Biomechanics at KSU by Larry Noble, Specializing in Biomechanics of Exercise and Sport Courses I teach