Using an example from the shoulder girdle, explain how the arrangement of bones and joints allows for effective throwing movements. (3 marks)
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- The shoulder girdle’s ball-and-socket joint connects the rounded head of the humerus to the shallow glenoid cavity of the scapula. This arrangement creates extensive mobility through multi-directional movement.
- During the wind-up, the shoulder extends and externally rotates, which allows the arm to move behind the body. This backward positioning stores elastic energy in anterior muscles.
- In the forward phase, the shallow socket permits rapid shoulder flexion and internal rotation. Combined with the scapula’s mobility on the ribcage, this generates maximum throwing velocity through an extended range of motion.
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- The shoulder girdle’s ball-and-socket joint connects the rounded head of the humerus to the shallow glenoid cavity of the scapula. This arrangement creates extensive mobility through multi-directional movement.
- During the wind-up, the shoulder extends and externally rotates, which allows the arm to move behind the body. This backward positioning stores elastic energy in anterior muscles.
- In the forward phase, the shallow socket permits rapid shoulder flexion and internal rotation. Combined with the scapula’s mobility on the ribcage, this generates maximum throwing velocity through an extended range of motion.