Note to parents of kids in organized sports and to those of you with kids in middle and high school: Your kids may not be as active as you think.

A study from San Diego State University has found that kids who play softball, baseball or soccer still don’t get their daily recommended allotment of exercise. The government says kids should get at least an hour of good, hard exercise a day; kids in these sports only get about 45 minutes, on average. Of the softball players studied only 2 percent — mostly pitchers and catchers (the only players involved in every play), I’m guessing — got in their 60 minutes.

Why aren’t organized sports cutting it?

Too much standing around waiting to do drills, for one. Channeling back to my days as a Titan in the Young American Football League, it drove us nuts all the standing around and waiting our turn at shoulder pad-smacking fun. Certainly, drills to hone skills are important. But do the drills once or twice, then practice them in a scrimmage. They’re kids: They came to play.

While this next finding is hardly revealing, it’s worth repeating. According to a study published in the American Journal of Sports Medicine, kids 6 to 11 get twice as much exercise as kids 12 to 15. Kids 16 to 19 are even less active. The reason? The 6- to 11-year-olds are in grade school, and while gym class has been relegated to once a week, elementary kids still have recess to get their yee-haws out. Once they get to middle school and high school, they’re chained to a desk.

Organized sports are great. They encourage activity and they’re fun, or should be. But they may not be enough. Especially for middle and high schoolers.

For more on the studies, go here.

And that hour a day is important because … People who exercise a lot when they’re young have a better chance of avoiding the dread middle-age spread. That according to a study of 3,554 men and women aged 18 to 30. The study followed the group over 20 years and found that the men who stayed more active — meaning they met the minimum 150 minutes a week of moderate to vigorous exercise prescribed by the U.S. Department of Health and Human Services — ended up gaining 5.7 pounds less than their couch-embracing counterparts, while the active women gained 13.4 fewer pounds. Much of that benefit was seen in the all-important mid-section, where the men’s waistbands expanded 1.2 inches less, the women’s 1.5 inches less.

Staying active at a younger age may be more important for women, who tend to gain weight during menopause. “My comment,” Dr. Suzanne Steinbaum, director of women and heart disease at Lenox Hill Hospital in the Big Apple told the online NIH news service MedlinePlus, “is to train for menopause like you’d train for a marathon. If you start exercising before menopause hits and do that for 20 years, you don’t have to gain weight.

“Health,” she adds, “isn’t about flipping a switch. It’s about maintaining a lifestyle.”

For more on the study, go here.

Another reason young women should be active … That lack of a middle-age pooch could spare them the agony of osteoporosis later on, according to a study presented at the Radiological Society of North America’s annual meeting. This study analyzed 50 premenopausal women with a mean BMI of 30 (anyone with a BMI of 30 or greater is obese, according to the Centers for Disease Control). The women underwent an MR spectroscopy exam to evaluate the bone marrow fat of the fourth vertebra. The bone mineral density of that vertebra was then determined via quantitative computed tomography. Finding: the women with more visceral fat — fat located deep under muscle tissue in the abdominal cavity — also exhibited decreased bone density.

“Our results show that having a lot of belly fat is more detrimental to bone health than having more superficial fat, or fat around the hips,” said Dr. Miriam A. Bredella, a radiologist at Massachusetts General Hospital and assistant professor of radiology at Harvard Medical School in Boston.

For more on the study, go here.