Humans in Work System Environment - Fundamentals and Assessment Tools for Occupational Ergonomics - page 94

min VP: test person

ED: recovery time

E D

100

experiment

model

50

75 W

50 W

25 W

Vp: Kl

Vp: Gu

t arb = 0,5 h

Vp: So

W dyn = 50 W

20 25 30 3

T eff °C

FIGURE 5.16 Comparison between experimental results and model test results concerning the recovery time.

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5.5.4.1 Biomechanical Analysis and Functional Anatomy
The presentation of the human body in mechanical systems of equations (deductive model systems) is a
characteristic for the biomechanical analysis. It allows to type exactly the quality and quantity of a move-
ment and, thus, to estimate the mechanical load of the human body in a certain circumstance of load.
The biomechanical analysis does not deal with those corporal structures in which these powers are pro-
duced and absorbed. These are the topics of the functional anatomy. In this context, the coordination of
movements is an organized interaction between different skeletal elements and muscles.
Isolated individual movements are rather uncommon. The consideration of normal movements
reveals that entire units of muscles are involved in the carrying out of even simple movements. More
or less all muscles of the full arm collaborate in the rather simple process of outstretching the arm. Fur-
thermore, the mustered power spreads out through the entire brace of the torso. So this movement,
which seems to be so easy demands a reasonable interaction of a great amount of muscles of the
entire body. The analysis of such muscle units as a complementary view of the biomechanical analysis
is quite useful for the practical work system design, in order to identify the bottlenecks in building up
power and moving. This applies especially for all forms of posture work, whereby the powers released
to the outside are negligible compared to the inner powers.
Realizations from physiology, which are useful for the coordination of movements mainly refer to the
minimization of the energetic and physiological effort in consideration of the complex functional system.
Movements do not only consist of a summation of tetanic twitches of several muscles, but are determined
by the inertia powers, the attenuation powers, and the elastic powers of the sinews, muscles, and liga-
ments of the extremities.

5.5.4.2 Movement Informational Processes
An idea of the complexity of movement informational processes can only be achieved once an attempt
is made to accomplish a movement that is familiar to others but unfamiliar to you. The informational