TM Srinivasan
(Source: KYM Darśanam, November 1994, Vol. 3, No. 3)
Practice of Āsana-s has become the prime pre-occupation of teachers and students of Yoga. While Āsana-s have an important role in maintaining homeostasis at the physiological level, it is obvious that it is not the end all of Yoga practice. Indeed, when Patañjali defines Āsana in a single aphorism comprising of just three words (Sthira Sukham Āsanam), it is clear that its importance lies in providing the qualities of ‘Sthira and Sukha’ for the practice of Antaraṅga Yoga.
Āsana-s can be done isometrically or isotonically. When we maintain a posture for a length of time, then the posture is being carried out with isometric muscle contraction (Iso – equal to, metric – length, i.e., muscle length is constant). For example, if one performs Mayūrāsana, the hand muscles maintain a constant length, yet are working intensely since they are carrying all the body weight. When a person is moving in and out of Āsana-s, then he or she is doing this with isotonic muscle stretch (when the tone muscle is constant). The muscles then carry a fixed weight.
In either case, practice of Āsana is very different from other forms of exercise because in Āsana, the importance is on muscle stretch. Muscle stretch is important from two points – for relaxing and for better control of the muscle. The word relaxing is not used in the sense of sitting in a chair and day-dreaming. The word ‘relaxing’ is used in a scientific sense, when the muscle activity is reduced considerably below its ‘resting value.’ Thus, if an electromyogram is taken during normal rest and compared to its value during Āsana practice, the concerned muscles will have less electrical activity during stretch! Electromyogram is a simple method of using electronic amplifiers to detect electrical activity – in much the same way as ECG is used for observing cardiac activity. The muscle relaxation has a therapeutic value in resting an overworked and tensed muscle. Often, muscle pain due to sprain is also reduced after a stretch.
The next advantage of Āsana practice is that it provides for better coordination and control of the muscles used. This is a more complex physiology to explain and it is also a very recent knowledge in the science of rehabilitation engineering. Every muscle is endowed with a large number of motor fibers through which the brain sends information for muscle activity. Further, and for us a more important point, the muscle in its turn sends information to the brain regarding its own status, such as the amount of stretch and the weight it is carrying. This is vital and ensures that we do not suddenly collapse while trying to carry an impossible weight and it also guards us from tearing a muscle or a tendon by an improper stretch.
Slow stretch and maintaining the stretch are the ways we activate the muscle when we carry out Āsana-s. The stretched muscle sends a barrage of inputs to the brain with its status information and the brain maintains a coordinated action. The brain’s response to the inputs from the muscle depends on the type of information it is receiving, such as how quickly the muscle is stretching and how much of the stretch is maintained at any time. By manipulating these two parameters alone, we can modulate the brain signals to the muscle and help conditions of inactivity, tremor or spasticity. This benefit arises due to the activating of the complex feedback loops in the motor, nervous and sensory nerves which now function as one harmonious system.
Now, we do not carry out Āsana-s in a random fashion. There should be a pose-counterpose sequence so that a set of muscles stretch as the antagonists carry weight and vice versa. With such carefully thought out sequences, it is possible to activate the motor system for proper strength and coordination. Further, we need to breathe while moving in and out of Āsana-s.
The next question to ask is, “While practising Āsana-s, some do it without paying attention to the breath. Others consider conscious breathing an integral part of Āsana practice. Which of the two is the right method of Āsana practice and why?”
Physiologically speaking, the correct technique of breathing is to exhale during a forward bend and to inhale when arching the back. Following this pattern consciously could improve the stretch in Āsana and thus, could bring greater benefit to the person as compared to inattentive breathing. Many people who are affected by the disease of the times, namely psychosomatic stress are barely aware that they are breathing, let alone how they are breathing. If you were to ask the person to do a forward bend, he/she will be at a total loss with respect to the breath. Inhaling while compressing the abdomen could build up excessive inter-thoracic air pressure putting a strain on the heart. If the person has an unstable cardiac condition, he better watch out!
So what comes ‘naturally’ is one of the habits and it may not necessarily be a good one. This is also true of persons who have asthma and for whom exhaling is difficult. For such a person, practising Āsana with exhale during forward bend will be extremely beneficial. Further, tying the mind to the breath will ease the wandering mind and calm it in preparation for Prāṇāyāma.
Another level of complexity is usually incorporated, where we have to breathe properly and visualise appropriately during an Āsana practice. Through appropriate visualisation, the flow of Prāṇā through the system is helped, thereby benefiting the system as a whole.
All in all, for proper stretch, breathing should follow the technique described above. This will promote better muscle coordination and strength than in inattentive or improper breathing patterns. Further, by concentrating on breathing, the mind is quietened further. Through visualisation of Prāṇic energy flow in the Nāḍī-s, as one practises Āsana-s with proper breathing, the Prāṇic currents have a chance to traverse the Nāḍī-s unimpeded, further benefiting the practice. Now, we are talking about Yoga!
T.M. Srinivasan, Ph.D. is a former President, Director of Research at the Gladys Taylor McGarey Medical Foundation, USA. He was also a teacher at the Mandiram.