Updated February 07, 2011
Side plank is more difficult than the last two plank positions we worked with, plain and dolphin arm. Supporting yourself in a sideways position is much less stable.
In Pilates we take advantage of unstable positions to help us develop core strength as the core muscles have to work hard to make the subtle adjustments that keep the form we want.
Side plank takes support from the whole body, especially the abs. But in side plank you are going to need your core to provide even more stability for the pelvis, and you will need a lot of shoulder stability and arm strength as well.
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