(CBS) There's a new threat to America's national security, and it has nothing to do with terrorism or rogue states.
It's our fat, out-of-shape young people.
According to a new study, conducted by researchers at Cornell University, a growing number of potential military recruits are simply too fat too enlist.
The percentage of military-age men whose bodies exceed the Army's enlistment standards for body fat has doubled over the past 50 years, the study found. Among military-age women, the percentage has more than tripled.
All told, 5.7 million American men and 16.5 American women of military age were ineligible for duty in 2007 and 2008 because they were overweight or obese, the study showed.
"The implications of rising obesity for the U.S. military are especially acute given its recent difficulties in recruiting a sufficient number of new high quality service members in the midst of combat operations overseas," concluded the study's authors, John Cawley, associate professor of policy analysis and management, and Catherine Maclean, a doctoral student, both at the university.
"Almost one in four applicants to the military are rejected for being overweight or obese -- it's the most common reason for medical disqualification," Cawley said in a written statement. "With an active war in Afghanistan and continuing operations in Iraq, it is well-known that the military is struggling to recruit and retain soldiers. Having a smaller pool of men and women who are fit enough to serve adds to the strain and creates even more problems for national defense."
The study, published by the national Bureau of Economic Research, followsthat the Army has rejiggered its basic physical training program, making allowances for recruits who are fat and out of shape when they show up for basic training.
Sit-ups and long runs are out, the New York Times reported last August. In their place are exercises that look a lot like yoga and pilates.
"What we were finding was that the soldiers we're getting in today's Army are not in as good shape as they used to be," said Lt. Gen. Mark Hertling, who oversees basic training for the Army, told the Times.
The new fitness regimen was rolled out this year at the Army's five basic training posts, which collectively handle about 145,000 recruits a year, according to the paper.
"Kids are just not able to do push-ups," Curt Gilroy, the Pentagon's director of accessions, told the Army Times last year. "And they can't do pull-ups. And they can't run."
Can they defend us?
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