Of course it means they are hungry. Feed them
Why don't you try something just for giggles, feed one until it will not eat anymore. then see how often it will eat. Keep doing it. Not forever mind you, just a week or two.
You may learn that they are a bit like you. If your only fed a tablespoon per meal, you will act totally different then if allow to eat what you want.
Now, to understand the use of calories is another story. In most cases, monitors getting fat is not about to many calories consumed. Its more about the conditions that restrict the use of calories. So they are stored as fat.
Also, humans, think of everything on a schedule or regular basis. Monitors do not, they think in terms of availibility. Food is not always availible to them, they are designed to comsume all they can find, They use up a temporary resource, then conserve energy, when food is not availible. We for some reason cannot think like that.
What it means in captivity is, feed lots when its needed and do not feed at all when its not. How simple is that? What? you can't not feed them for a few weeks? why? they do that all the time in nature.
I used to work at a local zoo, then the director hired me to give a report on the Herp dept. So I did. One of the things I found out was, they had a feeding schedule, they fed every other monday. I passed out. What the heck does that have to do with a living animal??????????????????????????????????????????????????????????etc. FR