When it comes to  accomplishing things in business and life, willpower is a powerful weapon. Master its powers and you can do amazing things, such as finish graduate school or permanently lose a pile of weight. Take it from William Wooditch, author of "Always Forward: Discover the 7 Secrets of Sales Success," which is centered around the idea that people cannot sustain forward movement without the unconditional resolve to give and do their best every day, without retreat or surrender. Here's how he says you can train yourself to have more willpower.

1. Manage your stress so you don't defeat yourself.

In other words, pick your battles.  Willpower originates in the brain's prefrontal cortex, which can be damaged by stress, impairing your ability to exert your will. The prefrontal cortex also needs to be fed, so keep glucose levels steady by eating small meals and fiber-rich carbohydrates every few hours. And prepare high quality snacks and meals ahead of time so you always have an alternative to fast food on hand.

2. Solve, don't quit on problems.

Your stick-to-it resolve in the present directly correlates with your future ability to execute and finish a task, process or project. Coming up short and quitting is a learned behavior just as finding the  will to push through and finish is a developed one.

3. Don't stay in a state of willpower depletion.

Focus your energy and know when to lay off and find the humor in a situation. Stop pushing through things, learn to relax and let it go. Some positions are untenable. Attempting to surmount or overcome the unwinnable is like grinding gears in a car with a lot of loud noises, smoke and no forward motion.