Muscles and Movements How muscles work to create movement Types of muscular contractions.
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Transcript of Muscles and Movements How muscles work to create movement Types of muscular contractions.
Muscles and Movements
• How muscles work to create movement
• Types of muscular contractions
How muscles work• All skeletal muscles create movement
by pulling on the bones they attach to• Muscles can only pull, they can never
push• Muscles work in opposing pairs, where
one causes the movement while the other controls it
• Example – biceps / triceps
Reciprocal Inhibition
• One muscle contracts while the other relaxes and causes the limb to move
• More examples – hamstrings/quadriceps– pectorals (chest) / trapezius (upper
back)
Pairs of Muscles• Muscle doing the work = AGONIST• Muscle relaxing = ANTAGONIST• Example 1 – arm curl (upwards): • Agonist = biceps / Antagonist = triceps• Example 2 – standing up after a squat: • Agonist = Quadriceps / Antagonist =
Hamstrings
Types of Contractions
Isotonic• muscle length changes during contraction
Isometric• muscle contracts and its length stays
same
Isotonic Contraction
Concentric• Muscle length shortens during contraction• Bending of the joint• Example – biceps during arm curl (upwards)
Isotonic Contraction
Eccentric• Muscle lengthens during contraction• Straightening of the joint• Example – biceps during arm curl
(downwards)
Isometric Contraction
• Muscle applies a force without changing its length
• Example – quadriceps during a wall sit, work very hard to prevent body from sliding down the wall to the floor
- static balance in gymnastics