This first line, the Superficial Back Line (SBL) (Fig. 3.1), is presented in considerable detail, in order to clarify some of the general and specific Anatomy Trains concepts. Subsequent chapters employ the terminology and format developed in this chapter. Whichever line interests you, it may help to read this chapter first.
The Superficial Back Line (SBL) connects and protects the entire posterior surface of the body like a carapace from the bottom of the foot to the top of the head in two pieces – toes to knees, and knees to brow (Fig. 3.2/Table 3.1). When the knees are extended, as in standing, the SBL functions as one continuous line of integrated myofascia. The SBL can be dissected as a unity, seen here both on its own and laid over a plastic classroom skeleton (Figs 3.3 and 3.4).
The overall postural function of the SBL is to support the body in full upright extension, to prevent the tendency to curl over into flexion exemplified by the fetal position. This all-day postural function requires a higher proportion of slow-twitch, endurance muscle fibers in the muscular portions of this myofascial band. The constant postural demand also requires extra-heavy sheets and bands in the fascial portion, as in the Achilles tendon, hamstrings, sacrotuberous ligament, thoracic-lumbar fascia, the ‘cables’ of the erector spinae, and at the occipital ridge.
The exception to the extension function comes at the knees, which, unlike other joints, are flexed to the rear by the muscles of the SBL. In standing, the interlocked tendons of the SBL assist the cruciate ligaments in maintaining the postural alignment between the tibia and the femur.
With the exception of flexion from the knees on down, the overall movement function of the SBL is to create extension and hyperextension. In human development, the muscles of the SBL lift the baby’s head from embryo- logical flexion, with progressive engagement and ‘reach- ing out’ through the eyes, supported by the SBL down through the rest of the body to the ground – belly, seat, knees, feet – as the child achieves stability in each of the developmental stages leading to upright standing about one year after birth (Fig. 3.5).
Because we are born in a flexed position, with our focus very much inward, the development of strength, competence, and balance in the SBL is intimately linked with the slow wave of maturity, as we move from this primary flexion into a full and easily maintained extension. The author of Psalm 121, who wrote T will lift up mine eyes unto the hills, from whence cometh my help’, is enabled to do so by the Superficial Back Line.
