well first... GOOD JOB on switching to home cooking.. best thing you can do for him.
So is it that he doesn't like going for walks?? Layla is NOT Crazy about walks AT ALL... so what i do is... dress her all up warm... she wears a sweater and jacket... and every time we get to the corner (we walk around the block) or if the sidewalk ends to cross the street, she has to stop, sit and then she gets her favorite treat. SO now when we go for a walk..s he still resists.... but once we get to the first corner she is SO excited... and the rest of the walk is fast fast fast.. lol.. can't get to those corners fast enough

but it took a few walks for him to get the hang of it