NEW YORK - MARCH 17:  A woman lifts dumbells during a workout at Warrior Fitness Boot Camp gym March 17, 2009 in the Midtown neighborhood of New York City.  Two former Marine sergeants, one an Iraq War veteran, began the boot camp-style training gym in 2008, bringing the exercises and drills they did as young Marines at the notorious Marine Corps Recruit Depot at Parris Island to more sedentary New Yorkers.  Most customers do the vigorous, team-style workouts 3-4 times a week, with workouts beginning before sunrise at 5:30 am.  (Photo by Chris Hondros/Getty Images)
Get more than a six-pack by working out
CNN Chief Medical Correspondent Dr. Sanjay Gupta explains how routine exercise can help your brain as well as your body.
02:39 - Source: CNN
Your Brain On 3 videos
NEW YORK - MARCH 17:  A woman lifts dumbells during a workout at Warrior Fitness Boot Camp gym March 17, 2009 in the Midtown neighborhood of New York City.  Two former Marine sergeants, one an Iraq War veteran, began the boot camp-style training gym in 2008, bringing the exercises and drills they did as young Marines at the notorious Marine Corps Recruit Depot at Parris Island to more sedentary New Yorkers.  Most customers do the vigorous, team-style workouts 3-4 times a week, with workouts beginning before sunrise at 5:30 am.  (Photo by Chris Hondros/Getty Images)
Get more than a six-pack by working out
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