In the modern world, multitasking is our mantra. Our brains process a blur of cell phones, instant messages, email and television, amidst 60-hour workweeks. How often do we concentrate on just one task, uninterrupted?Meditation is a powerful strength-training regimen to buff up our mental muscle and improve our waning ability to focus. “The clearer the mind, the more focus you will have,” says Deb Shapiro, meditation expert and co-author of “Be the Change.” “Any form of meditation is going to help with mental clarity, because you are giving the mind time to be quiet.When the mind gets rested in that way, it comes back in a much more vibrant sense.”Rather than a time to relax, meditation presents a mental challenge, and with it comes serious potential to sharpen our minds. A 2007 study published in the “Proceedings of the National Academy of Sciences” found that only five days of 20-minute meditation training resulted in significantly better attention and stress control, compared to a group that participated in other relaxation training. And a 2009 UK study found significantly higher cognitive flexibility, sustained attention and self-reported mindfulness in meditators.How to start: Begin by clearing your mind and concentrating only on your breath. Breathe deeply but naturally, from the middle or lower part of your torso. Visualize a cloudy sky, and watch the clouds slowly disperse to reveal only clear blue. Or visualize a lake clouded by muddy water. The mud gradually settles and clears, leaving only crystal water that allows you to see to the bottom.If your mind wanders to other thoughts, acknowledge them, release them and return to your breath. Like weight-lifting repetitions, you’ll want to gradually increase your stamina by working up to increased periods of meditation, as you feel comfortable and capable. “The most important thing is to be patient and not give up,” says Shapiro. “The more you do it, the more the mind actually becomes quiet and focused.”