Why is the Buddha represented as a rotund man?

I am asking this respectfully... with no disrespect intended to those who practice Buddhism. I am genuinely curious about how, in a country and period of history where people were slender, and Buddha gave up everything, why is he portrayed as being so large? It doesnt make sense to me from a religeous standpoint, or from a historical one either. Can someone clarify this? I would appreciate it if there is any doentation about this. Thanks to anyone for helping, and again, I am asking with all due respect. Thank you.....