The “Distort” command deforms the selection contour.
This command has several options which allow to increase or reduce the deformation. It is not possible to foresee the result and you have to experiment.
A higher threshold shrinks the distorted selection. A lower threshold makes the selection bigger.
A higher “Spread” increases the deformation.
A higher “Granularity” increases the deformation.
A higher “Smooth” decreases the deformation. You can Smooth horizontally and/or Vertically.