The 2014 Winter Olympics is currently underway in Sochi, Russia. And despite some concerns over security and human rights, it seems to be going rather well (at the time of writing).

Anyone watching the Olympics will have noticed how the competitors look very different than their counterparts from 30 years, 50 years, and 80 years ago. But why?

This video explores the science behind how Olympic athletes look. Things have changed considerably over the years, with each event now having its own special requirements in terms of body shape and size.

In some ways this is bad, as it means your average joe doesn’t stand a chance. But it’s good in that it proves how diverse we are, and how particular people are built for particular sports.