Eugene Schwartz uses the analogy that the mind is like a horse. If you work it too hard, it will “drop dead”. You’ll stop being productive and go stale. Not permanently, but on a given day, if you exhaust yourself mentally, you won’t continue doing your best, most creative work.
To combat this problem, Schwartz devised a method that’s come to be known as the 33 minute rule. Whatever he was working on, he would set a timer for 33 minutes and 33 seconds, and when that timer went off he would stop whatever he was doing – however important – and take a break for a few minutes to clear his head.
Stretch your legs, get some fresh air or have a drink of water. During those 33 active minutes, you focus and use them effectively. When you’re conscious that you’re working inside a finite block of time, you make every minute count.
Thanks to Damien Elsing for this tip – find his post at http://writetodone.com/2013/02/28/how-i-turbocharged-my-freelance-writing-productivity/