Carlos Diaz has been running some kind of race for the past several decades. Not only has the executive worked his way up from a fish veterinarian to the head of the world's third-largest aquaculture feed company, he's also managed to squeeze in 12 marathons.

It was partly his love of challenges and the need for a purpose that led him to spend most of his career in aquaculture.

“In aquaculture, there are always new things to learn and new challenges.