Muscle contraction and relaxation

The diagram shows the leg muscles of an athlete leaving the starting blocks for a race.

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Which muscles contract and which relax to bring about the change from position 1 to position 2?

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Guys can someone explain why the answer is C


there are several ways to answer this question:

  1. when a muscle contracts it has a “shorter” and “fatter” appearance, when it relaxes it has a “longer” and “thinner” appearance
    From this we can tell P relaxes, R contracts
    For the other muscles this is much less obvious to see

  2. think of what movement the muscle is responsible for
    To do this imagine a string is attached to the insertion points on the bones, if the string is pulled how would this move your limb?
    The calf muscle drawn here is a “string” tied from the top of your tibia and to your tarsal bones, when you pull the string your foot will be pulled back and “pointed”
    So T contracts during the movement.

3)If an anterior muscle contracts, its opposite posterior muscle must relax and vice versa
So eliminate all the options that put P and R or S and T in the same column

  1. if you’ve used any gym equipment try to think of what muscles are activated when you do a movement, to go from sitting to standing like a squat you should feel your glute muscles contract.
    So Q contracts in this movement

Hope this helps! also where is this question from?