TY  - COLL
AU  - Jöllenbeck, Thomas
A2  - Jöllenbeck, Thomas
DB  - BISp
DP  - BISp
KW  - Biomechanik
KW  - Elektromyographie
KW  - Kinetik
KW  - Kniegelenk
KW  - Leichtathletik
KW  - Muskelkontraktion
KW  - Muskulatur, ischiocrurale
KW  - Sprint
LA  - eng
PB  - Czwalina
CY  - Hamburg
TI  - Electromechanical delay of the harmstrings and its significance for the analyse and optimisation of sprint running
TT  - Elektromechanische Verzögerung in der hinteren Oberschenkelmuskulatur und ihre Signifikanz für die Analyse und Optimierung des Sprintlaufs
PY  - 1998
N2  - Only the exact knowledge of the electromechanical delay (EMD) of a muscle, the phase-shift between the onset of EMG and the onset of force provides important conclusions about the mechanical effectiveness of a muscle becoming evident via the corresponding EMG. By means of an underlying, hypothetical EMD of 40 ms for all investigated muscles TIDOW/WIEMANN (1994) could demonstrate that the horizontal acceleration in sprint running was not mainly generated by the knee extensors but to a predominant proportion by the hip extensors. However, in the past publications reported EMD values of the knee extensor and hip flexor muscles ranging between 32 ms and 118 ms. Under consideration of such EMD values the results of TIDOW/WIEMANN (1994) could be brought into question again. In order to shed light upon this question 68 subjects performed three explosive maximal iso-metric voluntary contractions (MIVC) with their hamstrings. The established EMD values for the before not examined hamstrings were only 24 ms +/- 7 ms. Hence the results of TIDOW/WIEMANN (1994) become even more significant concerning the importance of the hamstrings for sprint running. Underlying EMD values of 24 ms for the examined muscles the mechanical effectiveness of the knee extensors seems to be restricted to the front support, whereas the hip extensors generate mechanical energy throughout the complete support phase. The submitted results underline the importance of further investigation of the EMD in order to promote the analysis and optimisation of sprint running and suggest to redefine the EMD for all muscles involved in sprint running. Verf.-Referat
SP  - S. 90-94
BT  - Sport Kinetics '97 : theories of human motor performance and their reflections in practice. Vol. 1: Lectures. Fifth International Scientific Conference of the International Association of Sport Kinetics common with the Section "Sportmotorik" of the German Association for Sport Science (dvs) and the Institute of Sport Science of Otto-von-Guericke-University of Magdeburg. Magdeburg, 3-6 September, 1997
M3  - Gedruckte Ressource
ID  - PU200302000371
ER  -