Table 8.

Functional characteristics of muscles in the sway-back posture

Muscle	Lengthened	Shortened	Hypoactive	Hyperactive
Trapezius (middle and lower part)	+		+
Serratus anterior	+		+
Rhomboideus major and minor	+		+
Erector spinae part thoracic (upper part)	+			+
Erector spinae lumbar part (upper part)	+		+
Rectus abdominis (lower fibers)	+			+
Abdominal internal oblique (anterior part, lower fibers)	+			+
Abdominal internal oblique (posterior part, lower fibers)	+		+
Abdominal external oblique (lower fibers)	+			+
Iliacus	+		+
Psoas	+			+
Two-joint hip flexors	+			+
Suboccipital		+		+
Sternocleidomastoid		+		+
Scaleni		+		+
Trapezius (superior part)		+		+
Pectoralis minor and major		+		+
Erector spinae lumbar part (lower part)		+	+
Rectus abdominis (upper fibers)		+		+
Abdominal internal oblique (anterior part, upper fibers)		+		+
Abdominal internal oblique (posterior part, upper fibers)		+	+
Abdominal external oblique (upper fibers)		+		+
Gluteus maximus		+	+
Hamstrings		+		+

Note: the symbol “+” means that the muscle meets a certain criteria