Sex efficiency through exercises : special physical culture for women / by Th. H. van de Velde ; [photos, by E. Steinemann].

(6) Major Pelvic Rotation, in supine (or recumbent) position (knees raised) (Film 4). Lie flat on back. Raise the knees, then separate them. Proceed as in foregoing Exercise 5. Note.—The difference between the minor and major pelvic rotations consists in the effects of the knee posture, which is closed in the first exercise and opened in the second. (7) Squatting or Crouching Swing (Film 5). Sit back in kneel-heel position. Then move the nates slowly sideways, above the heels so that the seated position is taken. The arms are best held sideways stretched out loosely—not drawn taut—and slightly below shoulder level; in this posture they help to balance the trunk. The pelvis should be lifted by a vigorous half-circular swing—not jerk—across the heels and again sideways, and the movement repeated. Beginners and persons of stout and full build may support themselves partly on their hands while learning this exercise in their first attempts. But the aim of this exercise is to so strengthen both the muscles and their control that the pelvis may be swung completely from left to right (and vice versa) without help from the hands. The nates should be lifted clear of the heels at each swing. This will imply a slight forward movement of the pelvis, which should be lifted and not rolled or dragged. Note.—I have indicated the expert way of performing the pelvic swing in the squatting position, as it can be and is performed by accomplished gymnasts. But it demands expert advice and should only be attempted by women whose pelvic viscera, including bladder, kidneys, urethra and lower intestine, as well as the genital tract, are free from displace- ment or disease. (The importance of healthy pelvic organs has been emphasised before in this study, but may well be mentioned again.) If there is any suspicion of displacements or inflammatory conditions, the vigorous swing should not be attempted, but the trunk should be raised more—and very slowly—and still in the squatting position, to help the movement from side to side.