Sorry, that looks like skin and bones the way those ribs are so visible and the hip bone 'blade' seems so prominent.
I'm not one who let's dogs get over weight FWIW. Even thought I do know all to well what you mean. So, so many feed trash to their dogs and they are bloated sausages with feet.
This is the other one (adult).
We do not feed our dogs commercial food, they get raw meat and bones (mostly deer etc.), fresh vegetables, essential oils, eggs and meat from our own chickens etc. all organic. This not only makes for a healthier dog but also for a more defined appearance than those who are puffed up by dry dog food containing all sorts of artificial rubbish.
And our dogs are intact = not neutered.