I mean sitting and closing your eyes for 20 minutes or so. Sit still and simply observe the thoughts that come into your mind. Don't try to solve any problems. Just watch and let go.

take your mind off your main task so it can relax.

Here are some free classical music downloads.

Use reading for 10-20 minutes as a reward for 30 minutes of focused work. Use an egg timer to keep track.

Reboot your brain with a caffeine nap.

drinking a cup of coffee and then immediately taking a 10-15 minute catnap gives you an energy boost.

To compete in the sport may make you tired physically, but will wake you up mentally.

You might be in brain drain because you simply don't have sensible objectives.

playing a game lets you know life doesn't always have to be so serious and focused. Make time for play too!