[thesnowdog]

I've always been told the same thing but my experience pretty much matches yours.

I can eat what I want as long as I keep up my daily 7km walk which takes me about an hour or so. I've always found walking easy but I've never been able to run more than 500m probably due to being a somewhat sickly kid with annual bronchitis and a limited lung capacity.

The handful of times I've stopped walking for various reasons over the last twenty years I've quickly got up to about 120kg (I'm 6'7") but as soon as I start walking again the excess 20kg falls off pretty quickly in a month or two and maintaining 100kg is simple.

I've never had any luck modifying my diet.