This research examined the influence on performance of no-pause and mean delays of 0.97 s and 1.5 s between the eccentric and concentric phases of the stretch-shorten cycle movement of internal rotation (IR) of me upper arm. Videography and surface electromyography were used in the assessment of 19 athletes throwing a baseball in a manner that constrained all degrees of freedom other than upper-arm IR. Results demonstrated that the pectoralis major, latissimus dorsi, and anterior deltoid muscles were all active at above 100% maximum voluntary contraction (MVC) during IR. The maximum velocity of the wrist decreased with increasing pause time between me eccentric and concentric phases of the IR movement. A mean 21.9% augmentation to the maximum wrist velocity was recorded when the no-pause delay and a mean delay of 1.5 s were compared. There were no electromyographically discernible differences recorded either prior to or after release for any of the monitored muscles during IR across the pause conditions. It is evident therefore that the benefits of a prestretch during external rotation (ER) have a significant influence on the subsequent velocity of IR.
Bruce C. Elliott, Kevin G. Baxter and Thor F. Besier
Neil E. Fowler and Adrian Lees
The aim of this study was to compare the kinetic and kinematic characteristics of plyometric drop-jump and pendulum exercises. Exercises were filmed (100 Hz) from the sagittal view and manually digitized; the data were smoothed and differentiated using cross-validated quintic splines. Ground reaction force data were sampled using a Kistler force platform sampling at 500 Hz. Differences between movement amplitudes and coordination strategies were assessed using t tests and conjugate cross-correlations. Pendulum exercises involved a greater range of motion at the ankle and knee but less motion at the hip joint than drop-jumps. Although different in absolute terms, the exercises used a similar coordination strategy. Drop-jumps resulted in greater peak vertical ground reaction forces than the pendulum exercises although the latter involved a greater net impulse. The similarity between the movement patterns for the two modes of exercise led to the conclusion that pendulum exercises offer a training stimulus similar to that of drop-jumps.
* Philip Roosen * Rudi Tielemans * 11 1999 15 4 361 372 10.1123/jab.15.4.361 The Effect of Patellar Taping on Quadriceps Activity Onset in the Absence of Pain David Parsons * Wendy Gilleard * 11 1999 15 4 373 380 10.1123/jab.15.4.373 Internal Rotation of the Upper-Arm Segment during a Stretch-Shorten Cycle
, Minimal Stretch-Shorten Cycles in Rehabilitation Robert Moss PhD, ATC 11 1997 2 2 6 6 49 49 54 54 10.1123/att.2.6.49 Contemporary Conditioning The DAPRE Technique Terrance L. Foust PTA Martin A. Fees MS, PT, ATC 11 1997 2 2 6 6 13 13 14 14 10.1123/att.2.6.13 Prevention and Rehabilitation
Paul Comfort, Christopher Thomas, Thomas Dos’Santos, Paul A. Jones, Timothy J. Suchomel and John J. McMahon
status on power absorption & production during lower body stretch-shorten cycle movements . J Strength Cond Res . 2010 ; 24 ( S ): 1 . doi:10.1097/01.JSC.0000367087.27639.48 25. Bosco C , Komi PV , Ito A . Prestretch potentiation of human skeletal muscle during ballistic movement . Acta
John R. Harry, Max R. Paquette, Brian K. Schilling, Leland A. Barker, C. Roger James and Janet S. Dufek
.1016/j.jbiomech.2014.06.013 10.1016/j.jbiomech.2014.06.013 25001205 13. Cormie P , McGuigan MR , Newton RU . Changes in the eccentric phase contribute to improved stretch-shorten cycle performance after training . Med Sci Sports Exerc . 2010 ; 42 ( 9 ): 1731 – 1744 . PubMed ID: 20142784 doi:10
Nicola Giovanelli, Filippo Vaccari, Mirco Floreani, Enrico Rejc, Jasmine Copetti, Marco Garra, Lea Biasutti and Stefano Lazzer
twitch contractile properties . J Electromyogr Kinesiol . 2013 ; 23 : 1215 – 1221 . PubMed ID: 23770003 doi:10.1016/j.jelekin.2013.05.002 23770003 10.1016/j.jelekin.2013.05.002 26. Wilson GJ , Elliott BC , Wood GA . Stretch shorten cycle performance enhancement through flexibility training
Deepika Singla and M. Ejaz Hussain
economy . Sports Med . 2009 ; 39 ( 11 ): 903 – 921 . doi:10.2165/11317850-000000000-00000 10.2165/11317850-000000000-00000 19827859 4. Cormie P , McGuigan MR , Newton RU . Changes in the eccentric phase contribute to improved stretch-shorten cycle performance after training . Med Sci Sports
Mehrez Hammami, Rodrigo Ramirez-Campillo, Nawel Gaamouri, Gaith Aloui, Roy J. Shephard and Mohamed Souhaiel Chelly
Analysis for the Behavioural Sciences . 2nd ed. Hillsdale, MI : Erlbaum Associates ; 1988 . 10. Cormie P , McGuigan MR , Newton RU . Changes in the eccentric phase contribute to improved stretch-shorten cycle performance after training . Med Sci Sports Exerc . 2010 ; 42 ( 9 ): 1731 – 44