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ELITE SII
They assume in other words the same role of a natural impulse transmitted by the
motor nervous system. Normally the muscle relaxes and returns to its original state
them at the end of the contraction.
Isotonic and isometric contractions
The isotonic contraction reveals when, in a movement of our body, the interested
muscles produce a state of constant tension. The isotonic contraction reveals
when, in a movement of our body, the interested muscles produce a state of
constant tension. Instead, when the joint heads of a physical segment are blocked
and the musculature produces a tension, we talk about an isometric contraction.
In the event of the electro stimulation an isometric contraction is preferred because
it fosters to obtain a more effective control.
The distribution of the different types of fibers in the muscle
The relationship between the two main categories (type I and the type II) can vary
in sensitive way. There are muscular groups that are typically constituted by fibers
of type I, like the soleus, and there are muscles that have only fibers of type II like
the orbicular muscle. But in the most part of the cases we have a simultaneous
presence of various types of fibers.
The studies lead on the distribution of fibers in the muscle have put in evidence the
strait relationship that exists between the motoneuron (tonic or phasic) and the
functional features of fibers from it innervate and have demonstrated as to a
specific motor activity (and sports in particular) can determine a functional
adaptation of the fibers and a modification of the metabolic features of the same
ones.
Motor unit type
Tonic ST
Phasic FT
Phasic FTb
In order to make a tissue pass from the phase of rest to the one of excitation, by
means of an induced electrical stimulus (impulse of the electrostimulation), some
conditions are necessary:
- the current amount
- the duration of the stimulus that must be adapted to the corporeal
district that is wanted to be stimulated.
From this consideration, for the excitation of a tissue, the relationship between the
duration and the intensity of the stimulus is particularly important and not only the
value of the peak of the intensity. This relationship varies according to the muscular
district.
REV 5 DEL 16.10.2023
GENESY SII
Contraction type
slow contraction I
fast contraction II
fast contraction II b
DUO TENS
Contraction frequency
0 - 50 Hz
50 - 70 Hz
80 - 120 Hz
75
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