Imagine you are out exploring in the jungle (go on, why not?). You are alert. You are paying attention to every bit of flora and fauna around you. Suddenly, in front of you, you see a lion. A threat. Your heartbeat increases. Your blood sugar level is raised. The blood flow to your muscles increases so that you can run away, fast.
Maybe you tense your jaw, to appear more fierce.
Maybe you clench your fists, to appear stronger.
You probably lift your shoulders to protect your neck area.
You run away from the lion (he is not that hungry, so he doesn’t follow you) and you return home, where you feel safe and can relax.
Now consider a more urban setting. An office building.
Changes are happening left, right and centre.
You are continuously alert as you absorb all the new information around you, as you make sure you are not operating on an auto-pilot that is no longer suitable, as you address new problems for the first time.
You attend a meeting.
You learn about some changes that will affect you directly over the next few months. You leave the room with your shoulders up by your ears. You sit at your desk and try to relax. At least your computer is familiar to you. Then you notice the intranet has changed. You are on full alert again, your shoulders creep up to your ears once more. You find what you need and start to relax. But your mind wanders back to the meeting, and you try to assess what the new information means to you. Without you noticing, your shoulders begin to creep up to your ears again. Then you realize that the deadline for the progress report on the new project is tomorrow. Your heartbeat speeds up once again, as does your breathing.
You go home not even noticing that your shoulders are up by your ears and that you are holding your breath, as this has been the norm all day.
While the roaring lion situation is much more dangerous in the short-term, the urban setting scenario can have a long-term effect. Having your life threatened by a lion is more stressful but it is also punctual. It happens once (I hope!) and kicks off a series of physiological response, but soon these effects wear off and your body goes back to normal.
In every day life however, small stressors have an effect on your body continuously and unless you are aware of how you are reacting, the body never goes back to its original posture. This is why it is important to develop physical self-awareness, so that you know when your body is tense when it shouldn’t be and so that you can recognize the effect a new situation is having on you physically.