Manual mode auto iso question

Hi all. On m 7d when I am shooting my daughter playing sports or running around I like to set to a fast shutter speed , f5.6 then auto iso which works really good most of the time. I know this has been debated on th 7d forum and the basic feature that would be nice is to be able to underexpose to say -1 set shutter speed, apt, and have auto iso on to keep it at say -1 instead of 0. I was told this was a feature nikon has but not the canon 7d. Can the 5d3 do this?