Humans in Work System Environment - Fundamentals and Assessment Tools for Occupational Ergonomics - page 95

difficulty of a movement becomes clear in the observation of the first clumsy trial of playing tennis, ice-
skating, or chipping. This difficulty cannot be handled until the brain is able to store the movement
programs in a way as subprograms. This means that only the order to retrieve the subprogram has
to become conscious and, thus, engage the upper nerve center, after a movement is once available
as a subprogram.
One of this automated work takes place with very little mental load. One possibility to judge the degree
of automation of an activity is to examine the performance proportion, which is possible to carry out
besides the automated activity. This idea is based on the model of a single-channeled information pro-
cessing with defined maximal channel capacity. According to this, information processing degrees orig-
inating from different activities can be summarized additively to the maximal channel capacity.
The absence of the consciousness in automated work makes a wide division of labor with its continu-
ous repetitions bearable, since the “disencumbered” consciousness is able to deal with other things
but work.
Methods originating from information theory and control theory are the appropriate measures, if
one tries to quantify the entirety of information processing with the movement coordination instead
of trying to fractionate only the conscious part. In the majority of cases it is only possible to describe
manual aim movements with the help of information-theoretical and control-theoretical models.
These manual aim movements are interspersed to a certain extent between the individual “stationary”
movement elements, for example, grabbing, assembling, or joining. Regarding the entirety of the
motor activity, the signaling can be analyzed with the help of control technical systems by the use of
actuators handling elements, that is, the motor information transfer in general, which is also called
signal-motor work. Thereby, predications concerning work design can result.
5.5.4.3 Operations of Exercise
Each exercise starts with the comprehension of the rules, which determine the movements. These rules
are also called work methods (see also the remarks concerning work tasks in Section 5.3.2.2). A
condition for the perfection of the movement course by conscious and continuous repetition is this
view of the informational and motor operations in which a movement is integrated. Repetitions
lead to the fact that a consecution of operations eventually transfers to an automated component of
a conscious activity.
The quantitative and qualitative increase of performance, the decrease of mistakes, the decrease of the
required time, the decrease of energy effort and, furthermore, the decrease of different central-physiologi-
cal parameters of load, for example, the heart rate and electrical activity of working muscles are all criteria
of the exercise success.
Examinations concerning the contribution of individual movement elements to the exercise course
showed that an increase of performance could only be achieved by the use of temporal shortening of
the difficult movement elements (e.g., grabbing, assembling). Thus, it seems reasonable only to intensely
exercise the complex movements of a work course. This method is suggested for complicated and long-
term cyclic activities.
The exercise, according to the entirety method, is the most popular. Thereby, the whole task is carried
out from the beginning to the end before it is repeated. This method is used especially in situations where
the workers have already started producing for the manufacturing while still exercising (training on the
job). Financial incentives turned out to be effective for increasing the speed of practice.
The entirety method is a kind of active exercise. Thereby, the movement, which is to be accomplished is
orderly and actually repeated. Besides, these possibilities of coordination exercise, training forms are
possible, which are based on the fact that working persons store the movement as an “internal
model,” that is, that the working persons import, consolidate, or correct the informational program
of this movement. Thereby, it is possible to distinguish between observative, mental, and verbal training.
With the observative training the practicing person watches a very proficient person while carrying out
the movement. With mental training the trainees imagine the movement course. With verbal training the
affected people talk about the movement course.