Kansas State University Biomechanics Lab Research in Biomechanics at KSU by Larry Noble, Specializing in Biomechanics of Exercise and Sport P Courses I teach P Laboratory capabilities P Examples of master’s theses done in our biomechanics lab P Ongoing research in our biomechanics lab P Review of recent study on bat design

Kansas State University Biomechanics Lab Courses I Teach P KIN 330 Biomechanics P KIN 630 Design and Analysis of Exercise and Sport Equipment P KIN 718 Videographic and Cinematographic Analysis of Human Motion P KIN 825 Mechanical Analysis of Human Movement

Kansas State University Biomechanics Lab Biomechanics Laboratory Capabilities P Cinematographic equipment (up to 500 fps) Cameras, tripods, lights, marking supplies Analysis equipment and software P Videographic equipment Digital video cameras (up to 240 fps) SVHS cameras, VCRs, lights, marking supplies Equipment and software for 3D analysis P Electromyography equipment APAS 4-channel unit with preamplifies P Load measurement equipment AMTI force platform, load cells, load beams, accelerometers

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

Kansas State University Biomechanics Lab 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) 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)

Kansas State University Biomechanics Lab 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

Kansas State University Biomechanics Lab 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 1994) An examination of bat bending characteristics during the swing followed this study (Noble, Proc ISBS 2001)

Kansas State University Biomechanics Lab Does the “springboard”effect, or diving board mode, exist? Is it possible for hitters to take advantage of it?

Kansas State University Biomechanics Lab Procedures

Kansas State University Biomechanics Lab Procedures

Kansas State University Biomechanics Lab Results - Waveform Characteristics in Horizontal Direction

Kansas State University Biomechanics Lab Begin Swing 233ms PC Peak 41 ms PC Horiz Pk 38 ms PC

Kansas State University Biomechanics Lab

Begin swing 183 ms PC Peak bending and peak torque ~ 50 ms PC Impact – bat still bent back approx 20% of max

Kansas State University Biomechanics Lab 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

Kansas State University Biomechanics Lab Questions?