Dear Mr. Dad: Everyone knows about the crisis of overweight and obese kids. With the Winter Olympics just a few weeks away, I got to wondering whether so many kids being fat and out of shape will affect the United States' ability to compete (not necessarily in these Olympics, but in the future). What do you think?

A: Your question reminded me of a study I read a few years ago that found that children in the U.S. were 18 percent less "aerobically fit" than their parents were when they were the same age (worldwide, kids are 15 percent less fit, so we're a bit worse than average). Put a little differently, today's children take about 90 seconds longer to run a mile than kids 30-40 years ago. That's a big difference.

Thinking about that study reminded me of when I was 9 years old and came home bragging to my parents and grandparents (who were over for dinner) about how I'd won a race and was one of the fastest kids in school. Grandpa, who was 72 at the time, wasn't terribly impressed, and challenged me to a race. We went outside, and he beat me. Easily, and he let some of the air out of my inflated fifth-grade ego.

I should say, my grandfather wasn't a normal person. Throughout most of his life, he worked at one backbreaking job after another, did 100 pushups every day, and despite decades of twice-weekly trips to all-you-can-eat buffets where he had plate after plate of fried chicken and mac and cheese, he lived to 103.

As to your question, I'm not worried that our obesity problem will affect our country's performance in the Olympics or any other top-level sporting venue. Like my grandfather, elite athletes in any sport (except, perhaps, curling), aren't like the rest of us. There have always been and will always be freaks of nature who can do things that boggle the mind.

I do worry, however, about how the obesity epidemic will affect everyone else. Obese kids suffer from conditions that didn't used to appear until adulthood, such as high blood pressure, diabetes, liver disease, heart problems, and even osteoporosis. And, sick, out-of-shape children tend to grow up to be sick, out-of-shape adults.

Here's a little bit of irony for you: While children's fitness levels have been slipping, record numbers of kids are getting involved in organized sports. It's hard to reconcile those two ideas, but here's my theory about what's going on.

– Organized sports are highly structured and focus on developing and honing individual skills. But they don't encourage endurance.

– Schools across the country are getting rid of physical education programs. The majority of elementary, middle-, and highs schools don't require PE every day, and many allow kids to replace PE with other non-physical activities, such as community service. Many districts have even eliminated daily recess.

– Parents are so obsessed (often unnecessarily) with their kids' safety that they don't let them walk or bike to school.

– The amount of time kids spend on unstructured outside playtime has plummeted. Instead of running around with their friends, kids are texting, face-timing, Instagramming and playing games on their phone.

– Most children don't get the 60 minutes of daily sweat-inducing physical activity that pediatricians, fitness experts and the CDC recommend – largely because most parents don't make exercise a priority and enforce it.

For regular folks like you and me, the solution is simple. Take the kids out and make them exercise – with you, of course. It doesn't matter what it is, as long as it's strenuous. That probably won't turn them into Olympic athletes, but there's a good chance that it will help them (and you) live longer, healthier lives.

(Read Armin Brott's blog at www.DadSoup.com, follow him on Twitter, @mrdad, or send email to armin@mrdad.com.)