MyoBravo Bedienungsanleitung / Operators Manual
56
Muscular Stimulation
It is a known fact that nerves control muscles by transmission of neurological
codes. This code or message, depending on the required type of muscular fibre,
will be transmitted in varying frequency bands. The muscle begins to contract
when it receives electrical stimulus, whether the impulse is generated by the
brain or by electrical stimulation. The physiological method of neuromuscular
stimulation require impulses, that are similar in condition to the naturally
occurring nerve signals. Provided that the imitation of nature is as exact as
possible, electrical stimulation may, if necessary, be applied over a long periods
of time, without causing side effects. Muscular system of the sceleton
(horizontal striped musculus) consist of numerous long and thin fibres,
muscular firbers that span between tendons, by which they are linked to the
bones. The respective suitable stimulus is dependant on the type of muscular
fibre, that is to be reached. The main distinctions between the different fibre
type is as follows:
Type I (red muscular system)
This type of fibre is also known as ST-fibre (slow twitch fibres – slowly
contracting fibres). The necessary gain of energy for the functioning of the
muscles happens aerobically, that is through oxidative metabolism. The
mononeuron that stimulates this fibre, has a slow transmitting speed. These
type of fibres are thin and of red colour (which refers back to the existence of
myoglobin molecular). Internally these fibres contain a high number of
mitochondria and oxidative enzymes. Type 1 muscular system is extremely
resistant to tiredness, as it is responsible for all types of activities of tonic
nature, slow and are connected with the support of bodily posture. These
slow fibres are surrounded by a dense capillary network, which allows optimal
functioning of the aerobic metabolism by prolonged activity in connection with
a negligible expenditure of energy. The red muscle fibres bestow stability on the
bodily posture muscles and support the joint. This muscle system is very
important for all endurance sports like cycling, long distance running,
swimming etc.
Type IIa (white muscle system)
This type is also known as FOG-fibres (fast twitch oxidative glycolytic fibres
– fast contracting fibres with oxidative glycolytic metabolism). These are
stimulated by a motoneuron of the phased type that has a higher transmitting
speed than tonic motoneuron
.
The fibres are white because of the lack of
myoglobin and have a mixed metabolic activity. They are rich in glycogen and
glycolytic enzymes and also contain mitochondria enzymes, the whole
metabolism is more anaerobic than the aerobe-oxidative one. These fibres are
also equipped with a capillary network, that transports the necessary oxygen
for the aerobic process.
