One of the underlying themes of the Heart of Darkness is that humans are innately evil. There are many arguments that point to humans being innately good too, but at the end of the day, the topic still is open ended. In terms of fitness though, I believe that we are definitely “evil”.
The easiest thing to do when working out is to not work out at all. We as humans are always incline to choose the path which will offer us the most comfort. Exercising definitely does not mean comfort. In fact, it usually means the opposite, as we have to exert ourselves to achieve what we want. What further worsens the situation for us young people is that we fail to realize the long term implications of what we do today. So, instead of going out and exercising or doing other things, we choose instead to stay home and surf the internet. Even as we travel upstream in time, it gets more and more difficult to escape the heart of laziness. More responsibilities are constantly being added on, and fitness quickly takes a backseat to what may seem like more important things in life.
If we compare the Heart of Darkness to fitness, then laziness is definitely the “evil” in the book and we are all Marlows, believing that we can beat it but inevitably giving in. In the same vein of thinking, the best way to be saved is for us to have someone looking our for us, just like Marlow was looking out for Kurtz. Finally, if we are totally consumed by this laziness, then we will end up like just Kurtz, except fatter.