Basics of Stretching Introduction, physiology and application

Stretching is a form of exercise applied to skeletal muscles. Represents pressure in the direction of the muscle attachment points in order to distance them. Stretching stretches both muscles and adjacent tissues (tendons, connective tissue, peripheral nerves, muscle fascia). Stretching is synonymous with stretching and refers to the optimal range of motion of a joint.

Stretching is often performed by abducting the target muscle group relative to the torso. Its main task is to improve muscle elasticity, lengthen muscle fibers and improve overall tone.

What is not stretching

Stretching is not synonymous with yoga, ie. stretching is based on the physical practice of yoga, borrowing many movements and poses from there, but yoga is not stretching. Stretching (applied to increase flexibility) is not a warm-up. Many trainees stretch in an effort to warm up for their next workout, but static stretching and warming up should be distinguished as completely different activities.

The warm-up aims to prepare the body for the activities ahead: we distinguish between general and specialized warm-up. Physiological changes that occur in the body during the warm-up include an increase in temperature and metabolism in the muscles, blood circulation, improved oxygen supply. The benefits of warming up include the prevention of injuries and improved performance of the basic movements of the workout.

It should precede any physical activity, whether it is stretching or fitness training. Cold muscles are not susceptible to stretching and there is a high probability of injury if we try to perform it without prior preparation.

Physiology of stretching

The biomechanics of skeletal muscle are under our conscious control and work on the principle of opposites, for example: when we want to straighten the knee, the brain sends signals to the quadriceps, it tightens, and its opposing back thigh muscle relaxes and stretches. This action, in turn, triggers a sequence of physiological reactions that remain outside our logical awareness and are known as the stretching reflex.

In essence, it is a protective mechanism that protects the joint from injury. Receptors located in the joints, muscles and tendons detect movement and signal the central nervous system, which responds to the stimulus by regulating the momentary contractility of the muscle and its length. This in turn affects the range of motion of the working joint.

Thus, conscious biomechanical actions cause unconscious physiological reactions. The main sensory organs involved in controlling the length of muscle fibers are the muscular spindle and the Golgi apparatus. Moving the body in a given position initiates a chain reaction of biomechanical and physiological events.

Explanation of the terms “extensibility”, “mobility” and “flexibility”

Many trainees do not make much difference between these concepts. To avoid inaccuracies, here is the place to make some clarifications and make a distinction in terms.

Stretchability

Stretching refers to muscles, tendons and ligaments, ie. this is the ability of the fibers to increase their length under the influence of applied pressure. This concept should not be confused with “elasticity”.

Elasticity

Elasticity is a quality of muscles that allows them to regain their original shape after deformation – under the influence of weight or after stretching. When a muscle is shortened, its elasticity increases at the expense of extensibility; in case of muscle fatigue the extensibility increases.

Mobility

Mobility is a quality of joints that depends on several factors and relates to their range of motion.

Flexibility = extensibility + mobility

Flexibility is usually used as a general term uniting the above two. This is a person’s ability to perform movements with a wide range, it can be innate or acquired. Flexibility depends on both the mobility of the joints and the extensibility of the fibers, muscle tone and temperature, and muscle elasticity.

Muscle tone

Muscle tone is called the state of slight muscle contraction at rest. It is regulated by the work of the nervous system and maintains the posture of the body. “Good” and “bad” tone are conditional concepts, as “bad” refers to both extremes: at low tone there is poor posture, lack of coordination in movements. If the tone is too high, it is the so-called. “rigid”, overtrained, hard muscles. Good muscle tone provides us with freedom of movement and good coordination, delays the onset of fatigue.

Mobility and stability of the joints – the biomechanical “Yin and Yang”

Mobility and stability in the joints exist on the principle of opposites – the greater the mobility, the less stability. Feedback is also valid. There are three factors that determine the range of motion of each joint:

 

1.  The shape of the bone;
2.  The structure of the joint fossa / cavity and surrounding tissues;
3. . The muscles located around the joint.

The structure of the bones involved in the formation of joint connections contributes to the range of motion in a given joint. Large and deep, the hip joint has a limited range of motion on the three surfaces (frontal, vertical and sagittal), but it has stability that takes almost all the weight of the body. A shallower joint structure, such as the shoulder joint, has significantly greater mobility, but finds it difficult to stabilize more weight.

The capsule and ligaments surrounding the joint are made up of fibrous connective tissue. This whole structure tightens the bones together and also affects joint mobility and stability. The bones that form strong and stable joints (as in the case of the sacroiliac joint) are associated with extremely strong ligaments that limit the mobility of the “joint”. On the other hand, the bones that make up the shoulder joint are joined by much looser and more stretchable ligaments, allowing a wide range of motion.

In the immediate vicinity of the joint are located muscles, or the so-called. joint stabilizers. Muscle contraction not only serves to produce movement, but also to stabilize the joint, ie. the degree of muscle contraction affects the mobility of the joint. Rigid (overtrained, overstretched, hard) muscles limit the range of motion, and plastic (with good tone, “soft”) increase it.

Stretching lengthens the muscles that stabilize a joint, allowing greater freedom in the movement of the joint. Regular stretching exercises gradually relieve tension in the muscles that stabilize the joints and provide more comfortable movement in all joints.

How flexibility would improve our strength performance

Stretching is often overlooked by fitness enthusiasts. It is usually used only when there is muscle fever, spasm or other type of muscle discomfort. Relieving such conditions is an indisputable advantage of stretching exercises, but in fact they are able to both alleviate existing painful conditions and prevent the occurrence of such, and even help in the implementation of certain fitness exercises in which we encounter difficulties.

Benefits and applications of stretching as part of our fitness training:

• Recovery – It is a well-known fact that over time, joints, tendons and ligaments depreciate, and intense training and the use of heavy weights accelerate this process. Stretching has proven to be a factor in muscle recovery, tendon toning and improving joint function.
• Pain management – everyone is familiar with the feeling of stiffness in different parts of the body, which are manifested with particular intensity after performing certain strength exercises performed with great weight. A few properly chosen stretches would greatly minimize these inconveniences.
• Optimization of the technique for certain exercises – a big obstacle in the way of many trainees is the stiffness of the muscles throughout the back of the body: adequate stretching exercises for these parts would significantly improve the performance of a number of movements such as: deadlifts, squats in all its variants, various Olympic movements, etc. Improved mobility in the shoulder girdle, on the other hand, would favor absolutely all movements, including carrying weight over the head.
• Stability, balance, control – all these qualities can also be developed through the regular application of stretching training. They will help develop a better sense of body movements, and control of the center of gravity would help increase stability when working with both your own weight and extra weights.
• Biochemistry of good mood – research has shown that stretching exercises lead to increased production of endorphins in the body. They are responsible for a number of physiological reactions of the body, such as the feeling of satisfaction, balance and well-being.

When is the time for stretching?

As mentioned at the beginning, stretching, increasing the length of muscle fibers should not be used as a form of pre-workout warm-up. It itself requires good training and warm muscles to be performed safely and to get the most out of its application. The best place for stretching exercises would be after strength or conditioning training, or on a separate day set aside for active rest.

Sources used :