How To Have Larger Player Touch Area, But Still Have Physics Boundary Only Work On Player Itself?

What’s approach do I need to use to have say a:

a) Touch area for my player (in a game) of say 100x100 pixcels, but

b) Player itself is 50x50 pixcels, so the physics boundary re crashing into walls has to work on this

c) I note that my physics.addBody I’m letting it work out the 

Background: I have my player as a “display.newGroup()” and then add the player image to this.  I had applied the physics to the overall display group before.  To get what I want, I tried doing the following:

i) add 2nd touch circle (which can be invisible) to the player

ii) move the physics.addBody from the overall player (display object) to the player image

==> but when I try this approach the physics boundary detection doesn’t seem to work, hence I’m asking this general question here…

Is there a way to have the overall display object (player object) as the physics object, but then insert a larger circle into the display object in a sense that it won’t trigger increasing the physics boundary?  

(actually I guess one approach would me to manually specific the radius of the physics area - will leave this question in place, as I would still be interested to know if there is a way to insert an image into an object in a manner which won’t affect the existing objects physics boundary)