Restrict your for next loops based on data subsets. For example, instead of making a for next loop that checks the status of all the entity/sprites/whatever create a seperate list that only the data that needs to be checked for that frame.
Type BadGuy
Field X,Y,Data
end Type
Type VisibleBadGuy
Field VBadGuy.BadGuy
end Type
For VBadGuy.VisibleBadGuy = Each visibleBadGuy
....do stuff to it
next
Type BadGuy
Field X,Y,Data
end Type
Type VisibleBadGuy
Field VBadGuy.BadGuy
end Type
For VBadGuy.VisibleBadGuy = Each visibleBadGuy
....do stuff to it
next