4 types of muscle contraction
For people immersed in the world of sports training, it becomes necessary to know the types of muscle contraction, how they function and the importance they have within the body.
It is not only important for the mere fact of knowing what they consist of, but because it is relevant to know what the body is subjected to when performing physical exercise. Try to design and carry out your training routines with sufficient knowledge and theoretical bases. Do not forget!
Types of muscle contraction
Muscles perform voluntary and involuntary movements, which depend on the type of muscle that makes them up and the region that controls them. For example: the central nervous system (CNS), specifically the brain, is responsible for controlling voluntary movements. For its part, the spinal cord focuses on reflex arches or involuntary movements.
Within the movements of the muscles, different types of muscle contraction stand out, which can be classified according to their stimulus or movement. Some are even classified as contraction only with exerting tension without movement.
Isometric contraction
Isometric contraction refers to the static position of the muscle in conjunction with great tension. In this, there is no evidence of lengthening or shortening of the involved muscle, therefore, it maintains its length.
Based on the above, this type of contraction is also called "static" and is much more common than you might think. Even many of the exercises that are performed on a daily basis are included in it.
A clear example is the isometric or conventional plate. When executing it, the body is kept still and the muscles are subjected to constant tension.
Isotonic contraction
Within the types of muscle contraction, the isotonic is considered the antithesis of the isometric. In this, there is muscle movement and, therefore, the length of each muscle involved is constantly modified.
In addition, it is the most used contraction in the day to day, thanks to the movements of the body in general. In this contraction there are 2 main subtypes: eccentric and concentric.
- Eccentric contraction: refers to the extension of the muscle after the execution of a movement. It goes from shortening to lengthening gradually. It is evident when extending the arm, for example, but with a constant tension in it.
- Concentric contraction: it occurs in the opposite way to the eccentric one. Here the contraction occurs from elongation to shortening, gradually. When flexing the arm with constant tension on the muscle, this subtype can be noticed.
Isokinetic contraction
Isokinetic contraction is quite similar to isotonic, due to the characteristics they share. They are even often confused on a regular basis.
This type of contraction refers to the shortening and lengthening of the muscle fibers, but in a uniform and constant way. In other words, the speed of the contraction should not generate any change, nor decrease, nor increase.
The main difference from isotonic shrinkage is uniformity. While the isokinetic is constant, the isotonic does not require uniformity in its speed. Usually, this type is presented in the technical gesture of rowing.
Auxotonic contraction
To culminate with the main types of muscle contraction, it is necessary to mention the auxotonic. This type is the combination of isotonic and isometric contraction. In this they converge as a whole; the isotonic is the first to be present and the isometric is the one that culminates in the auxotonic contraction.
It usually occurs in exercises in which elastic bands are used. For example: you start by stretching the band with one arm, there the isotonic is presented. Immediately after, you must hold it at a fixed point, and at that moment the isometric is evident.
Advice on types of muscle contraction
It is likely that even when performing certain exercises you have doubts about what types of muscle contraction you are doing. However, you should not worry, quite the opposite. Seek professional advice to understand the subject in greater detail and depth.
Remember that it is relevant to know how the body behaves while you exercise, but knowledge is not acquired magically. Both a coach and a physiotherapist will be able to guide you and clarify any type of doubt you have in this regard.
All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.
- Sachlos, E., & Auguste, D. (2008). Contracción Muscular. In Biomaterials.
- Rasch, P. J. (1994). Fisiología de la contracción muscular. Kinesiología y Anatomia Aplicada.