Study finds focusing on a single sport often leads to stress fractures in teen girls.
The youth sports world is competitive, with many teen athletes spending 20 hours a week engaged in their sport.
The intense activity might be too much for some teen girls who may be setting themselves up for long-term health problems.
All of this rigorous activity can increase the risk for stress fractures in pre-teen and teen girls according to a new study from Harvard Medical School and Children's Hospital Boston.
"This is a really critical window for girls. Most of the bone development -- we see huge growth during this time," explains Dr. Alison Field.
Dr. Field led the research.
She says girls were more likely to suffer stress fractures when they specialized in one high-impact sport year-round like gymnastics, cheerleading, basketball or running.
Even a tiny bone break at this age can lead to long-term health consequences, like an increased risk for osteoporosis, if the fracture isn't given time to heal.
Cross-training with lower impact activities could help ease the pressure on girls' fast-growing bones, which aren't as dense at this age as boys'.
"So instead of running, could they use an elliptical machine, or could they do some swimming" advises Dr. Field.
It's good advice for girls who may need to start thinking of their bone growth as more of a marathon than a sprint.
Nearly 7,000 pre-teen and teen girls were followed for seven years for this study.