Philip Friedman and Gail Eisen, two students of Romana Kryzanowska, published the first modern book on pilates, The Pilates Method of Physical and Mental Conditioning, in 1980 ^[4] and in it they outlined six "principles of Pilates". These have been widely adopted - and adapted - by the wider community. The original six principles were: concentration, control, center, flow, precision and breathing.

Concentration

Pilates demands intense focus: "You have to concentrate on what you´re doing. All the times. And you must concentrate on your entire body".^[5] This is not easy, but in Pilates the way that exercises are done is more important than the exercises themselves.^[5] In 2006, at the Parkinson Center of the Oregon Health and Science University in Portland, Oregon, the concentration factor of the Pilates method was being studied in providing relief from the degenerative symptoms of Parkinson's disease.^[6]

Control

"Contrology" was Joseph Pilates' preferred name for his method and it is based on the idea of muscle control. "Nothing about the Pilates Method is haphazard. The reason you need to concentrate so thoroughly is so you can be in control of every aspect of every moment" ^[7] All exercises are done with control with the muscles working to lift against gravity and the resistance of the springs and thereby control the movement of the body and the apparatus. "The Pilates Method teaches you to be in control of your body and not at its mercy".^[8]

Centering

In order to attain control of your body you must have a starting place: the center. The center is the focal point of the Pilates Method.^[9] Many Pilates teachers refer to the group of muscles in the center of the body – encompassing the abdomen, lower and upper back, hips, buttocks and inner thighs – the “powerhouse." All movement in Pilates should begin from the powerhouse and flow outward to the limbs.

Flow or efficiency of movement

Pilates aims for elegant sufficiency of movement, creating flow through the use of appropriate transitions. Once precision has been achieved, the exercises are intended to flow within and into each other in order to build strength and stamina. In other words, the Pilates technique asserts that physical energy exerted from the center should coordinate movements of the extremities: Pilates is flowing movement outward from a strong core.^[10]

Precision

Precision is essential to correct pilates: "concentrate on the correct movements each time you exercise, lest you do them improperly and thus lose all the vital benefits of their value".^[11] The focus is on doing one precise and perfect movement, rather than many halfhearted ones. Pilates is here reflecting common physical culture wisdom: "You will gain more strength from a few energetic, concentrated efforts than from a thousand listless, sluggish movements".^[12] The goal is for this precision to eventually become second nature, and carry over into everyday life as grace and economy of movement.^[11]

 Breathing

Breathing is important in the Pilates method. In Return to Life, Pilates devotes a section of his introduction specifically to breathing "Bodily house-cleaning with blood circulation" ^[13] He saw considerable value in increasing the intake of oxygen and the circulation of this oxygenated blood to every part of the body. This he saw as cleansing and invigorating. Proper full inhalation and complete exhalation were key to this. "Pilates saw forced exhalation as the key to full inhalation." ^[14] He advised people to squeeze out the lungs as you would wring a wet towel dry.^[15] In Pilates exercises, you breathe out with the effort and in on the return.^[16] In order to keep the lower abdominals close to the spine; the breathing needs to be directed laterally, into the lower ribcage. Pilates breathing is described as a posterior lateral breathing, meaning that the practitioner is instructed to breathe deep into the back and sides of his or her rib cage. When practitioners exhale, they are instructed to note the engagement of their deep abdominal and pelvic floor muscles and maintain this engagement as they inhale. Pilates attempts to properly coordinate this breathing practice with movement, including breathing instructions with every exercise. “Above all, learn to breathe correctly.” ^[17]

We breathe on average around 18,000 breaths per day. Posterior lateral breathing is a way of breathing that facilitates bibasal expansion of the ribcage, this encourages the breath to travel down into the lower lungs and cleanse the blood by the exchange of oxygen with carbon dioxide. To understand this concept properly you have to first learn to expand and release the ribcage without deliberately breathing in or out. The in-breath (inhalation) and out-breath(exhalation) should occur instinctively as a result of the conscious expansion and release of the ribcage. This is how you would do this: You place your hands on your lower ribs with you thumbs facing the back of your ribcage, try not to think of breathing, relax your upper abdominals and expand your ribcage to the side against the soft resistance of your hands. Release the expansion of the ribcage by first melting away the area of the clavicles. You can also try this with a scarf around the lower ribcage. You will not be able to expand and release the ribcage effectively if you try to contract your abdominal muscles to expand the ribcage and if you try to contract the ribcage instead of first release it.

Now you should try to duplicate this action with conscious breathing in and breathing out. The in-breath (let it come) widens the ribcage laterally, posteriorly, and superiorly in the ratio of 60:30:10. That is 60% laterally, 30% posteriorly and 10% superiorly. The effect of this ratio of distribution is felt mainly as a back activity. The out-breath (gradually let it out) exits the body first through the gradual and gentle release of tension (intention) in the upper chest and breastbone area, without collapsing the front of the ribcage, and terminates through the activation of the power engine.^[18]