First lady Michelle Obama participates in a yoga class during a visit to the Gwen Cherry Park NFL/YET Center on Feb. 25, 2014 in Miami. The visit was part of a celebration around the fourth anniversary of Lets Move!, her initiative to ensure that all our children grow up healthy and reach their full potential. But a recent report card suggests that the nation's children aren't scoring well on physical activity. (Joe Raedle/Getty Images)

If you ever received a report card like the one issued on the physical activity of U.S. youngsters Tuesday, you simply wouldn't bring it home. You'd throw it away, bury it somewhere, stick it in a drawer and hope your parents forgot that they hadn't seen any grades for a while. When four "incompletes" are the best you can point to, it's time to get ready for summer school.

Specifically, the assessment of kids' physical activity included a B-, two C- grades, a D, a D-, an F and those four incompletes. Aside from the head-scratcher of deciding there wasn't enough information to grade 40 percent of the categories their own committee developed, the National Physical Activity Plan Alliance and the American College of Sports Medicine delivered another well-researched critique of how little exercise our children get and why.

Some of the lowlights: A D- in "overall physical activity," noting that just 24.8  percent of 12-15 year-olds get the recommended 60 minutes of physical activity each day; A D in "sedentary behaviors," because kids aged 6-19 spend 424 waking minutes each day on their rear ends; an F in "active transportation," which measured the proportion of kids who walk or bike to school (12.7 percent); and a C- in the share of kids who attend at least one phys. ed. class each week (51.8 percent).

The panel decided it didn't have enough information to assess how well the federal government, families and peers support physical activity, or the proportion of children who participate in daily, unstructured active play, among its other incompletes.

(The report card was delivered at a briefing of the Congressional Fitness Caucus. Did you even know there was a Congressional Fitness Caucus? I didn't. Maybe our representatives are spending a whole lot of time working out, because they certainly haven't done anything else since I could run a seven-minute mile. The 27-member panel includes the very fit chairmen, Reps. Aaron Schock (R-Ill.) and Ron Kind (D-Wis.), and, curiously, just two women. But I digress.)

“We hope the report card will galvanize researchers, health professionals, community members, and policy makers across the U.S. to improve our children’s physical activity opportunities, which will improve health, prevent disease and disability, and enhance quality of life,” said Peter Katzmarzyk, chairman of the 2014 report card research advisory committee.

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