Edited by: Fabrizio Butti
In physiology with the term Forza, we mean the ability of muscles to develop muscular tensions to overcome or oppose external resistances.
It is linked to the biological, biochemical and structural characteristics of the musculature, in part genetically predetermined and partly variable with training.
By mass we mean the space occupied by a body or the measure of its inertia, by acceleration we mean the variation in speed in the unit of time.
The studies carried out by different authors on the evolution of this ability, are all agreed in indicating a constant development of force during growth.
In males this development stops, reaching the maximum peak, at the age of 20/25 years, while in females this occurs around 15/16 years.
For many scholars the Strength is the " pure " physical quality because it is preparatory for any other physical capacity.
Any movement has a muscle contraction at its base; and depending on how it is executed, we can define it as fast, resistant or forceful.
Strength training, being a specific factor of each performance, is fundamental and is applied with very specific methodologies.
In training, the development of this ability occurs following two different paths: one linked to the general strength and the other to the specific one.
The first allows the integral construction of an individual, through exercises aimed at developing the entire musculature in a global and harmonious way; the second aims at developing the strength linked to the specific technical gesture of the competition.
The best period for the development of general strength is between 12 - 16 years of age (Filin, Joblonowski, Ciciskin) while, the increase in special strength, represents the most important goal in high level and age sportsmen greater (without neglecting the tonicity of those muscles that do not participate in the athletic gesture proper to the discipline).
In any case, the best approach is to work on the two aspects simultaneously and represents the ideal dosage to achieve perfect strength development.
FACTORS DETERMINING THIS CAPACITY:
- the transverse section of the muscles, therefore their dimensions;
- the frequency of impulses that the motor neurons transmit to the muscles;
- the ability to recruit motor units;
- the synchronization, in the act of contraction, of the various motor units.
The Force can progress through two factors:
- increasing muscle mass, thanks to work that leads to hypertrophy;
- adapting and modifying internal coordination.
In Body Building, for the development of muscular hypertrophy, it is preferable to use "fundamental" exercises, also called " multi-articular", which involve many muscle areas, working on 6/8 repetitions with a certain slowness in the eccentric phase.
The exercises must be carried out with a load of 75-80% of the ceiling, no more than 3/4 training sets, reaching the muscle failure between 6-8 repetitions, the technique of execution must be perfectly respected to avoid trauma.
The physiological principle on which the increase in muscle volumes is based is that of maximum destruction of the energy and protein compounds of the myofibre, to then reconstruct a higher heritage through the mechanism of supercompensation.
Supercompensation is a process by which the stimulus causes an uncomfortable condition, followed by a reconstructive reaction that exceeds the level prior to stimulation.
The training stimulus must be inserted in the right dynamic, at a time when the body has achieved supercompensation, in general, the sessions must have a gap of 36/48 hours.
The muscle
The muscle is made up of muscle fibers (cells) joined by connective tissue. Each fiber consists of a membrane with several nuclei and thousands of internal filaments, the myofibrils (the cytoplasm of the cell) that contain sarcomeres (contractile units).
Sarcomeres in turn consist of two filamentous proteins, actin (fine) and myosin (thick).
The length of the muscle fibers can vary from 0.05 mm to 30 cm.
The muscle fiber is therefore the morphological unit of the muscle ; the fibers are not all the same and have different characteristics.
Muscle fibers
Muscle fibers in humans can be of two types:
- white fibers (type II, fast, FTF);
- red fibers (type I, lens, STF).
In addition to color, these two fibers differ in their ability to produce muscular work differently; the whites are characterized by the speed and the intensity of the contraction, the red ones for the duration.
White fibers:
- high speed of contraction;
- low speed and working time;
- high ATPase activity;
- high glycolytic activity.
Red Fibers:
- low contraction speed;
- long working life;
- large and numerous mitochondria;
- low ATPase activity.
The range of fibers is wider than the one outlined and there are intermediate gradations.
Having said that it can be said that for the structuring of a personalized training program for the client, it is always necessary to keep in mind the type of muscle fiber on which to work.
Training and strength ยป
