We often hear that we should use our common sense when it comes to exercising and dieting.

But what really is common sense? How is it defined by one person to another?

From Wikipedia:

Common sense is what people in common would agree: that which they "sense" in common as their common natural understanding.
Some use the phrase to refer to beliefs or propositions that in their opinion they consider would in most people's experience be prudent and of sound judgment, without dependence upon esoteric knowledge or study or research, but based upon what is believed to be knowledge held by people "in common", so: the knowledge and experience most people have, or are believed to have by the person using the term.

But how do you apply that when it comes to fitness? Well if you know that an exercise is not good for you but you still do it, then you are not using your common sense. You don´t listen to what your common sense is telling you. What you are doing could actually be dangerous for you.

Diets, you go on a new hip crazy diet that is leaving you tired. Afterwards you blame yourself because you gained all the weight you had lost.
So why not use your common sense and eat on regular times, eating more vegetables and eating healthy instead. That will benefit you in the long run.

Your Doctor says you shouldn´t exercise for four weeks due to an injury, after four days you can´t stand staying inside any longer so you ignore your Doctor´s advice and go for a run. As a result your injury gets worse and you have to rest an extra week.

Maybe you say; yes but everyone knows this.
Yes, but then why do we all the time hear about people that have gone on crazy diets or ignored their Dr´s advice?

Why are we not being more careful with our health?
Are you applying common sense to your fitness routine? Or do you think this is all nonsense?