The problem with safety guidelines is that they make most playgrounds so uninteresting as to contribute to reduced physical activity.

Playgrounds don't look like they used to. Steep metal slides and wooden towers have given way to slow, plastic slides and carefully penned-in climbing contraptions. And forget about seesaws -- they're a thing of the past.

When kids are bored by unimaginative (read: safe) playground equipment, they're less active as a result, and with childhood obesity at epidemic proportions, that's a danger, too.

An interesting new investigation looks into this phenomenon. Researchers visited 34 daycare locations in suburbs and cities, including Head Starts, Montessori schools, YMCAs, and facilities at universities, corporations, and churches. Workers and parents were questioned about what they thought the main barriers to children's activity were. Injury concerns, financial constraints, and a wish to put academics first were among the chief reasons cited by parents and daycare employees for not encouraging more active play.

According to the study, the new, safer equipment often became boring because children mastered it so quickly. To make it more challenging, kids tended to improvise, walking up the slide the wrong way, or using supports as a climbing apparatus. Sometimes younger children were drawn to the older kids' equipment, presumably because it presented a more interesting set of challenges.