Yoga posture. Main Physiology
Yoga posture concept and main physiology that considered agonist/antagonist relationships as well as reciprocal inhibition opens new dimension of understanding of yoga movements and kinematics. This type of movement creates balance of physical and energy body as well. Agonist muscles contract to move a joint. During this movement antagonist muscle get stretched. When brain give signal agonist muscle to contact, it produced another signal for antagonist to relax. This is a great and very helpful physiological contribution for yoga practitioner.
If we are looking in physiology of Kurmasana (Tortoise pose) we can see that the trunk is flexed forward, it means that extensors (m.extensor spinae, m. quadratus lumborum) are stretched. Back flexors are getting relax.
Another good example of yoga posture is Paschimottanasana (seated forward bend). M. Psoas is getting flexed the hips, m. gluteus as antagonist will extends them.
Co-activation in yoga posture is another very interesting mechanism of contraction and stretching. It can be useful for creating length of the muscle. That called “facilitated stretching”. Stretching applies tension to the muscle and tendon. Receptor in muscle takes a signal to the spinal cord. Then spinal cord signal the muscle to relax. It helps to prevent the tendon from tearing. All skeletal muscles have have tendons it can be used for achievement of the length and dissolve blockages throughout the body.