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ANATOMY AND PHYSIOLOGY 



to the demands made upon it; repair does not keep pace with 

 wear and the muscle becomes not only tired from overwork and 

 lack of food but burdened with the poisons of fatigue. 



LARGE MUSCLES CLASSIFIED ACCORDING TO THEIR MOST 

 FREQUENT ACTION 



REGION. 



TRUNK 



HEAD 



SHOULDER 

 ARM. . 



FOREARM . 



ACTION. 



To enclose cavities and aid 

 in respiration 



To separate cavities and 

 aid in respiration 



Floor of trunk and aiding 

 above muscles. . 



To move spine and trunk 



To extend head. 



To flex head. . . 

 To rotate head. 



To lift shoulder 



To pull shoulder backward 

 To pull shoulder forward. . 



To pull arm forward 



To pull arm backward 



To abduct (lift) arm 



To adduct (pull downward) 

 To rotate arm, supination 

 To rotate arm, pronation 

 To flex forearm. . 



To extend forearm. . . 

 To rotate, supination. 



MUSCLES. 



To rotate, pronation. 



Intercostals. 

 Quadratus lumborum. 

 Obliquus externus. 

 Obliquus internus. 

 Transversus. 

 Rectus abdominis. 



Diaphragm. 



Levator ani. 



Coccygeus. 



Abdominal group. 



Erector spinae. 



Ilio-psoas. 



Erector spinae. 



Trapezius. 



Sterno-mastoids. 



Trapezius. 



Sterno-mastoid. 



Trapezius. 



Trapezius. 



Anterior serratus. 



Pectorals. 



Latissimus dorsi. 



Deltoid. 



Suprascapular. 



Pectorals. 



Latissimus dorsi. 



Infraspinatus. 



Teres minor. 



Subscapularis. 



Teres major. 



Biceps brachii. 



Brachialis. 



Brachio-radialis. 



Triceps. 



Supinator. 



Biceps brachii. 



Brachio radialis. 



Pronator teres. 



Pronator quadratus. 



