Medicine Ball throws/blocks

My most explosive fastest girls was doing medicine ball throws today and her left leg is the one that goes foward (kicks out).

In the back, her right leg goes back.

The throws are put into place for proper power for the start; therefore, should she switch her legs and place the left her back foot.

Sounds like she wants to take her first step with the left…

Switch feet with each rep and then worry about the starts. Don’t introduce anything that could lead to anxiety.

Why recommend switching feet…

Is it to determine what is her power foot

or

Is it to enhance power on both legs

or

Something totally different?