A yogic master was asked in Europe how long he himself practised yoga daily. He replied, 'twenty four hours.' This sustained awareness, discipline, or meditative state, seems difficult to understand. Nevertheless, recent research shows that, even a beginner practising relaxation and meditation techniques, is profoundly influenced after a relatively short period.
Agras and his associates continually measured, over a period of time, the blood pressure in hypertensives treated by means of relaxation techniques. They found that a decrease in blood pressure, due to these daily practices, lasted throughout the night. There was a significant difference between those who practised and those who did not.*1
Southam and his associates used a special device to measure blood pressure of hypertensives treated by relaxation, at twenty minute intervals during the normal working day. These patients showed a significant decrease in blood pressure.*2
It is highly likely that some other effects of relaxation or meditation also persist after the practice is finished and it is interesting to consider which mechanisms are involved. Voluntary relaxation may be viewed as a learned skill, and clinical experience shows that many patients or trainees, voluntarily and perhaps involuntarily, use their relaxation techniques during their daily activities. It is possible to explain in this way the drop in blood pressure in hypertensives during their working days but not during the night. That is why it is necessary to presume, in addition, that certain tuning of autonomic functions occurs, which may be achieved in different ways and which lasts after the practice is over.
Datey and his associates, who used yogic relaxation in the treatment of hypertensives, presume that the hypothalamus is influenced through the continuous feedback of slow, rhythmic proprioceptive and entero-ceptive impulses, which take place through passive breath observation.*3 The centres regulating autonomic nervous system functions and the cerebral cortex are connected, and in this way, the effects of autosuggestion or imagination or imagination-based techniques, can be explained.
Restricted environmental stimulation during the various relaxation and meditation practices, also seems important. Some meditation techniques include the repetition of a syllable, word or word-combination. Such monotonous activity of the speech centre in the dominant brain hemisphere may cause inhibition in the cortex and the temporary suppression of the more rational or logical part of the brain leads to relaxation.
According to various researchers, a decrease of anxiety often occurs during and after relaxation or meditation. Anxiety and fear could be viewed from an evolutionary point of view as relatively stereotyped reaction to the exposure to danger. Many wild animals react in this way e.g., to environmental change. Anxiety and fear are usually maladaptive, especially in humans living in sophisticated environments where the simple fear reaction is often, either unnecessary, or insufficient. The relaxation response, on the other hand, may be considered from an evolutionary point of view, as the state where assimilation, regeneration and rest take place, and such response has to be associated with the feeling of security. Anxiety and relaxation are then antagonistic and this antagonism is therapeutically utilised.
Even if many effects of relaxation or meditation last for some time after the practice is over, it is also useful, especially when environmental stress is heavy, to relax for a short time during normal daily activities. Some authors describe 'cue controlled relaxation' which means that when relaxation is performed, immediately a certain internal (e.g. tension) or external cue appears.
Differential relaxation is a term used to describe the practice where certain muscles are relaxed, while others are used in an appropriate way so that it is possible to remain relaxed e.g. while walking. Differential relaxation is practised in yoga too, and the correct performance of yogic asanas would be impossible without it.
Relaxation during and after yogic practices is not their only effect. However, certain amount of relief from psychosomatic tension and distress appears to be the most important reason why some people practise it.
*1. Agras, W. S. et al. : Relaxation training. Twenty-four-hour blood pressure reduction. Arch. Gen. Psychiatry 27 (8) 1980, pp. 859-863.
*2. Southam, M. A. et at. : Relaxation Training. Blood pressure lowering during the working day. Arch. Gen. Psychiatry, 39, 1982, pp. 715-717.
*3. Datey K. K. et al. : 'Shavasana': a yogic exercise in the management of Hypertension. Angiology, 20, 1969, pp. 325-333.