Configure data-fields on rest screen

I am wondering if it's possible to configure the data-fields shown on the rest-screen. I have seen the settings to configure the datafields in the settings for the activity, but I would like to be able to configure what is shown when in the rest-mode.
Most of all, I would like to be able to ad total activity time, but possibly also current time (clock) in there.
Is it possible to configure the rest-timers of the activites, or is it just possible for the active scrreens?