When the focus of movement becomes attaining a certain size or shape, your relationship with it changes.
When you start to move because of fear, your feelings about movement change too. Eating disorders steal the joy of being connected to our body and steal the joy of being able to express ourselves through movement. They turn movement into a way to demonstrate our self-hatred, rather than an act of self-love. Movement can become how we cause ourselves pain, rather than how we nourish our soul.
In 'The body keeps the score'
Bessel van der Kolk says “Our sense of agency, how much we feel in control, is defined by our relationship with our body and its rhythms: Our waking and sleeping and how we eat, sit, and walk, define the contours of our days. In order to find our voice, we have to be in our bodies – able to breathe fully and able to access our inner sensations.”