Muscles which are free from tension and at rest are said to be relaxed. Tension develops in muscles as they work during contraction and thus tension reduces as the muscles come to rest during relaxation. Support, comfort and a restful atmosphere are basic conditions for general relaxation and may prove effective without additional methods.

• Support
  Various forms and modifications of the lying position are used, to achieve full support of the body, the relative suitability of each one varying according to the condition of the patient and to individual preference.
• Comfort
  The ingredients of comfort include freedom to breathe deeply, warmth, abdominal quiescence and a mild degree of physical fatigue.
• Restful Atmosphere
  As physical and mental relaxation are interdependent, an effort must be made to secure a state of mental rest.

Support
(i) Lying Supine
A firm surface is essential, and if resilient also, as in the case of a good spring mattress, it is ideal, as it will mould itself to the body contours and give even pressure and comfort. At all costs plinths or beds which sag are to be avoided at they cramp the thorax and so throw additional strain on the inspiratory muscles. A head pillow is required which is sufficiently soft to prevent the head from rolling to either side, and to be well molded to support the neck posteriorly. A small pillow under the knees relieves tension on the Hamstrings and the ilio–femoral ligament, and consequently allows the pelvis to roll backwards so that the lumbar spine is straightened and supported. The feet are held in the mid–position by a sandbag or similar device, and each arm, slightly abducted at the shoulder and flexed at the elbow, rests on a pillow.
(ii) Half Lying
This is similar to the previous position but breathing is easier as there is less weight on the back and abdominal pressure on the under surface of the Diaphragm is reduced. An armchair makes quite a good substitute for a plinth or bed, the thighs are fully supported and the feet rest on the floor, or a footstool, or a T–shaped footrest.
(iii) Prone Lying
The head is turned to one side and may rest on a small pillow, if more comfortable. A firm pillow under the hips and the lower abdomen prevents hollowing of the back, and for women it should extend higher to avoid too much pressure on the breasts, the lower leg is elevated so that the knees are slightly bent and the toes free. A degree of medial rotation at the hips, causing the heels to fall apart, still further induces relaxation of the legs. Many find this position comfortable and use if for sleeping, others dislike it because of the rotated position of the head.
(iv) Side Lying
The measure of relaxation obtained is governed by the efficiency with which the shoulder and pelvic girdles are stabilized. The arm are leg which are uppermost may be rested on the supporting surface instead of on pillows, but some of the weight then falls on the trunk and this impedes respiration. The head pillow supports the neck and head in alignment with the body, and must not be too high. The majority of people sleep on the side, but few are conscious of the part suitable positioning for relaxation plays in promoting it.

Comfort
In addition to support and individual preference in positioning, for which some suggestions have already been made, the ingredients of comfort include freedom to breathe deeply, warmth, abdominal quiescence and a mild degree of physical fatigue. Removal of constrictive clothing, such as corsets and belts, is essential and any garters, buttons or suspenders liable to cause pressure must be removed. The room should be warm, but should have a free supply of fresh air, in winter additional warmth can be supplied by light but warm blankets, a covered hot–water bottle at the feet, an electric blanket or by non–luminous infra–red irradiation, but care being taken to avoid over–heating, as this leads to restlessness. For home use a warm bath gives the most even and pleasing type of heat, but its soothing effect must not be ruined subsequently by vigorous rubbing with a towel. A light well–balanced meal, rhythmical physical activity of short duration, such as a brisk walk in the open air, and attention to emptying the bladder before treatment are all conductive to general relaxation.