Hands down, my favorite productivity tool is a simple digital timer. I’ve written before at ProfHacker about some of the ways I use it for writing, for exercising, and for household chores. (If you don’t have a physical timer handy, you can use one of these online versions, or download one for your phone.)
One of the questions I frequently get asked is: how long should my timed interval be?
The answer depends on what you’re doing and how you want the timer to help you.
For instance, a quick five-minute clean up can be a great way to tackle a messy desk. When I’m engaged in serious writing, I’ll often set my timer for 40 minutes for concentrated effort. But many tasks fall somewhere in between.
To read the full, original article click on this link: Why 15 Minutes? - ProfHacker - The Chronicle of Higher Education
