A nimble mind truly starts with a nimble body—according to a recent study in the Journal of Strength and Conditioning Research, agility training improves cognitive function. It's the secret weapon of football and fútbol players, stunt doubles, and action heroes (Hugh Jackman in Wolverine and Jason Statham in The Expendables), who need to get ripped and agile, stat, and the coordination required spurs the brain's neuron growth—hence the bump in mental muscle.

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"Standard exercises split the body into parts, but that's not how it moves," says Adam Rosante, a personal trainer in New York City, who designed this routine. "These take skill and train the body as a whole."

The key is an agility ladder (available at most sporting-goods stores for about $25): "To stay within the boxes, you have to make precise movements. You cannot zone out."

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How It Works

Do each move rapidly, continuing to end of ladder, then repeat in opposite direction, resting 10 seconds in between. That's Round 1. Rest 30 seconds, then repeat circuit twice more.

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1. Dead Hop

Stand with right foot in first box, ladder extending in front of you, left leg lifted slightly, arms at sides. Hinge forward from hips, raising arms in front of you and lifting left leg behind you, until body forms a "T" [left]. Reverse movement and draw left knee to waist height as you explosively jump up and forward [top, right]. Land with right foot in second box. Repeat to end of ladder. Switch sides and repeat.

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2. Dip 'n' Flip

Sit with ladder lengthwise behind you, feet hip-width apart on floor, right hand in first box, left hand in second, fingers facing you. Lift hips. Do a triceps dip [A], then immediately flip over, placing right hand in third box, fingers away. Hop feet back. Do a push-up [B], then hop feet forward and flip to starting position, left hand in fourth box. Repeat.

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3. Sharp Shuffle

Stand with ladder lengthwise in front of you, right foot in first box, left foot behind you. Lower into a lunge. Jump, switching feet midair, landing with left foot in second box, right foot back in a lunge [left]. Jump and switch again, this time landing with right foot in third box, left foot back. Repeat.

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4. Precision Squat

Stand with feet shoulder-width apart outside the first box, ladder extending in front of you, toes turned out slightly, arms in front of chest [left]. Perform a deep squat, then explosively jump up and forward, landing with both feet together inside second box. Immediately jump up, landing with feet outside second box as you drop into a deep squat. Repeat.

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