Elliott Masie leads conferences and writes about workforce learning, business collaboration and emerging technologies. While his emphasis is on the business world, there are pieces that we as trainers can take advantage of. Read his blog post about choosing the right level of intensity and engagement in learning activities to achieve a goal.
http://www.learning2012.com/item/intensity-learning.html

Who is Elliott Masie? http://masie.com/MASIE-Information/who-is-elliott-masie.html