Fear is a natural survival mechanism where our bodies naturally react in a variety of ways. It may be that we find that breathing is more difficult or perhaps our body is reacting in other physical ways.
John Call (1) suggests : As soon as you feel fear, the amygdala (a small almond-shaped organ in the center of your brain) sends signals to your autonomic nervous system (ANS), which then has a wide range of effects. The ANS kicks in, and suddenly, your heart rate increases, your blood pressure goes up, your breathing gets quicker, and stress hormones such as adrenaline and cortisol are released. The blood flows away from the heart and out towards the extremities, preparing the arms and legs for action.
Our reactions will determine whether we can believe that we can overcome these fears and manage the situation we are in. The mind can be a very powerful tool in this.
Sometimes it takes time to overcome fear and that's OK, but unless we try, we won't know what it was like. Whatever the reaction, unless we learn to manage and control our fears we will always be afraid to try something new.
For me, it was stepping out and beginning a new business in my fifties and then, more recently it's been learning a new instrument and going back to the gym. Whilst I haven't physically climbed a mountain, at my age, that's plenty to be afraid of, but I might just give it a go.
So I challenge everyone to be just a little afraid and learn to climb your own mountain. Overcome the fear by pushing yourself. Give it a go. You might just learn something new and be glad you did!
Source : John A. Call; Psychology Today: The Anatomy of Fear https://www.psychologytoday.com/blog/crisis-center/200807/the-anatomy-fear