. Applied anatomy and kinesiology. ^ bnt it ismost noticeable in quick and forcible movements, like strikingdownward with a hammer or dumb-bell. The moA-ements of thearms in climbing also show^ this effect on the trunk muscles. Inall these movements the arms act like third-class levers, the fulcrumbeing at the spinal column and the trunk muscles acting on thesame side of it as the Fig. 160.—Action of trunk and limbs in arm depression: RA, rectus abdominis;EO, external oblique; RF, rectus femoris; P, pectoral; L, latissimus. Pushing forward with one or both arms while the body is e
. Applied anatomy and kinesiology. ^ bnt it ismost noticeable in quick and forcible movements, like strikingdownward with a hammer or dumb-bell. The moA-ements of thearms in climbing also show^ this effect on the trunk muscles. Inall these movements the arms act like third-class levers, the fulcrumbeing at the spinal column and the trunk muscles acting on thesame side of it as the Fig. 160.—Action of trunk and limbs in arm depression: RA, rectus abdominis;EO, external oblique; RF, rectus femoris; P, pectoral; L, latissimus. Pushing forward with one or both arms while the body is erector nearly so calls the abdominal group and the flexors of the hipsinto action to assist the triceps, upper serratus and pectorals. Theextensors of the trunk are fully relaxed in this movement, but byflexing the trunk and hips, bringing the body into a position morenearly horizontal and the arms more nearly in line with the trunk 266 GYMNASTIC MOVEMENTS it is possible to bring the extensors of the hips and spine into actioninstead of the flexors. The latter position makes the movement thesame as lifting overhead, with the arm-raising muscles acting andthe reinforcement by the extensors of the trunk and limbs. Throwing the medicine hall with both hands calls the muscles ofthe arms, trunk and limbs into strong action. Throwing forward from between the knees brings in the elevatorsof
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Keywords: ., bo, bookcentury1900, bookdecade1910, bookpublishernp, bookyear1917
