Dynamic Checkbox

Hi,

I want to ask you about how to get dynamic default values in the checkboxes. I have a database with the data of the web users. They fill a form and they select some checboxes with the days of the week. What I need is that users can actualize their data and create a form with the previously selected data . So, if user selected the checkboxes for Monday and Tuesday, when actualize the form the checboxes of Monday and Tuesday should be marked, selected. I thought it should be easy if it would be possible to use a shortcode for the default values. Is it possible with Contact Form? Is there any way to do it?

A lot of thanks.