Physiology, notes-2

Theory of muscle: muscular neuro-Physiology


The property of deforming and returning to the original situation.
Muscles are viscoelastic


If the muscles are trained, it increases the ROM (RANGE OF MOVEMENT) capacity.
Flexibility depends on the muscles that perform this function and on the muscles that stop it (antagonist muscles).


It is the capacity that our body has to contract the muscles in their articular ranges (for that the muscle must have contractile capacity) and that is one of the points that is going to be worked with BMT, because the contractile capacity is going to be governed by the motor cortex.

Therefore flexibility also depends on stability.
Intrinsic stability and are the passive tissues and structures not modifiable in an active way, (capsules, ligaments…) dependent or not on an active structure.

Intrinsic instability

This generates pain, when there is no pain there is stability. But in BMT, stability refers to extrinsic stability, the stability that will add to a joint is its muscles.

Can poor extrinsic stability lead to intrinsic stability?
If the function of the active tissue is missing it can affect the passive tissue.

Characteristics of passive stretching:

-Increase range of motion by improved vsicoelasticity of the muscle.
Improvements occur but are lost after about 60 minutes. Used in rehabilitation, to improve scarring and reduce adhesions.

Nervous system alterations, passive pre-competition stretching worsens motor movement.

Objectives of active therapies (BMT and Kinetics)

Improve performance for optimal contraction at different joint ranges, gain flexibility while maintaining stability and contraction capacity. Stability is to have  motor control,

Active tension:

Gamma neurons innervation
Alpha innervation –Motor control -Ability to regulate movement mechanisms -Disorders

One step in treatment is to treat muscle instability.

This is the stage where muscle function does not perform its normal physiology.
A symptom is muscle tension which we will treat with active techniques by stimulating alpha and gamma neurons and activating the motor cortex.
Muscle tension is a disorder where the muscle tone is elevated, muscle aches and pains.
We change the concept of gaining passive joint range to joint stability.

With your work using active techniques we will make the musculature contract well in all joint ranges so that tensions are balanced.

2 Neuromuscular physiology
Nervous system

-Brain and spinal cord relationships -Central Nervous System -Peripheral Nervous System
Motor cortex -Motor cortex -Supervises movement

-Brain -Higher centres -Basal ganglia
-Encephalic trunk
-Subcortical regions

Peripheral SN

How our spinal cord relates to target organs related to the musculoskeletal system.
The musculoskeletal system is related to the afferent and efferent systems through the neuromuscular spindle and Golgi organs.
An important role is played by the proprioceptive system, which informs us how our body adapts to movement and gives us information about our surroundings so that the nervous system can make the necessary adaptations and how the body perceives movement and adapt to the environment around us.

Neuromuscular spindles

This is in the parts most proximal to the tendon wrapped in intrafusal fibers. The central part is sensitive and the ends are related to contraction.
Central part – is a calibrated part that sends afferent signal through the motor neurons.

Extrafusal (Alpha) Intrafusal Gamma motor neurons

These are the ones that give quality to the movement and here is a part that in BMT and Kinetics we give priority.
When the muscle is in mid or long range, the gamma afferent gives a good signal. When there is a maximum concentration of informative signal it becomes unbalanced, without tension it does not send a sensitive afferent signal and loses its function.

The Gamma motor neuron innervates both ends (intrafusal fiber) to maintain tension and the central part is tensed, because it receives the stimulus and is therefore calibrated to have a good motor afferent response.
The Gamma motor neuron has the function of being able to contract the muscle to its maximum shortening.


When thinking of a stretch the body sends a reciprocal inhibitory signal to the antagonists.
If the antagonists send an inhibitory signal to Gamma it loses its function and will not contract due to the inhibition of these antagonists, the central part becomes unbalanced, loses the afferent sensitive signal, therefore the muscle generates an efferent motor response and Alpha will not be able to contract the muscle.
This inhibition changes the polarity of the membrane, which is why it is difficult to contract.
To contract it has to lower the polarity to 50 000 volts, if it is polarized it is inhibited because it is difficult to reach that level of contraction.

So we try to avoid inhibition.

Reciprocal inhibitions


Reciprocal inhibitions

When the agonist muscle contracts, it sends information via interneurons to the muscle to perform the opposite function to its own (antagonist muscle) so that in its inhibition it allows the movement.

Motor unit

Each motor neuron innervates over 150 muscle fibres, these are cells of the nervous system that produce the stimuli for the contraction of different muscle groups of the organism.


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