Biomechanics 4
Kinematics 1
Projekt: Cizí jazyky v kinantropologii - CZ.1.07/2.2.00/15.0199
Daniel Jandačka, PhD.

Kinematics describes the motion of bodies
•In sport and physical exercise we need to describe motor skills for the purposes of teaching,
training and skills evaluation.
•Moreover, the results in many sport disciplnes actually have the form of kinematic measures.

Motion is the process of changing position.
C:\Documents and Settings\jandacka\Plocha\Biomechanics Presentation\Obrázky\Aerobic 2.JPG
Motion of a body can be described only if we know its position with respect to time.
In order to study motion more easily, we classify motion as
1.linear
2.rotary
3.general.

Linear Motion
In linear motion all particles of human body travel the same distance during the same time.
http://screenshots.en.sftcdn.net/en/scrn/57000/57481/alpine-ski-racing-2007-2.jpg

Rotary Motion
C:\Jandys\KTV\Biomechanika\Prezentace_Brno\Biomechanics Presentation\Obrázky\Foto_swing.jpg
In rotary motion all particles of human body travel along a circle or its part, unless they are in
the axis of rotation.

General Motion
General motion is a combination of linear and rotary motions.
C:\Jandys\KTV\Biomechanika\Prezentace_Brno\Biomechanics Presentation\Obrázky\128_2891.JPG
If we resolve general motion into linear and rotary motions, it is easier to analyze.

Position
•In mechanics the position of a body defines its exact location in space.
C:\Jandys\KTV\Biomechanika\Prezentace_Brno\Biomechanics
Presentation\book-1\book-1\images\15\obr07.png
Figure Football pitch as the system of Cartesian coordinates (metrs).
In three-dimensional space we need three coordinates to describe the position of a body.
One coordinate of the Cartesian system of coordinates is vertical (z) and two coordinates are
horizontal (x, y).

Trajectory
•Trajectory is the path that a moving object follows through space.
http://l.yimg.com/g/images/spaceout.gif http://l.yimg.com/g/images/spaceout.gif
http://direct.coresites.mporatrons.com/whitelines/wp-content/uploads/2010/12/David-Benedek-Zugspitz
e-Double-Cork-Snowboarding.jpg
http://direct.coresites.mporatrons.com/whitelines/wp-content/uploads/2010/12/Perfect-Jump-Forum-Sno
wboards.jpg

Distance travelled
C:\Jandys\KTV\Biomechanika\Prezentace_Brno\Biomechanics
Presentation\book-1\book-1\images\16\obr08.png
Figure Distance travelled (blue) and displacement (black) of a footballer.
Distance travelled is length of trajectory.

Displacement
•Displacement is the shortest distance in the specific direction from the initial to the final
position of a body’s motion.
Displacement is a vector with both the length and direction.
The unit of measure is metre (m) and the symbol used is d.
C:\Jandys\KTV\Biomechanika\Prezentace_Brno\Biomechanics
Presentation\book-1\book-1\images\16\obr08.png

Thank you for your attention
Projekt: Cizí jazyky v kinantropologii - CZ.1.07/2.2.00/15.0199