In 2009 UCL published some interesting research in the European Journal of Social Psychology on how people form habits:
I find this very interesting as the Alexander Technique is all about changing habits - getting rid of inefficient ones and creating useful ones instead.
Clearly the human brain is incredibly versatile and the physical part of altering habits is relatively easy. In my experience it's the psychological part that people find challenging - people are often so strongly attached to their self-imposed limitations.
As a teacher I enjoy sensing people's potential for growth and change. I see the formation of new, better habits as a creative challenge, both in myself and in my pupils. I'm generally optimistic about people's ability to use the tools I'm able to show them, perhaps based on decades of seeing it work.
But I still find that people need more positive encouragement than anything else. So go on...choose something small that you'd like to change and take the first step...it's easy...and you'll feel so good...you might have to get up out of your chair...or write a note in your diary...but it will be well worth it!