Weight Gain Key to Healing Stress Fractures

An Ohio State University (OSU) study led by Timothy L. Miller, M.D. spent three years studying the relationship between stress fractures and the time it took for an injured Division I athletes to return to running.

They found that the lower the athlete’s body mass index (BMI) the longer it took to heal. For runners, being skinny is not better.

The OSU study identified 24 tibial stress fractures in 18 women. The researchers took into consideration the grade of the stress fractures using the K-M system. “This is a unique classification method because it considers both radiographic and clinical evidence,” Miller said.

A Grade I is a stress reaction that appears only on radiographic results and does not cause pain. Grade V is a nonunion stress fracture. “These are injuries that the patients have ignored or mistreated, and surgery may be needed to repair them,” Miller said. “Essentially, the body has given up trying to heal these fractures.”

The research team found that the average time required to return to running for those with a Grade V injury was 17 weeks, compared with 13.7 in grades II and III. The researchers also found that the women with BMIs lower than 19 were at a higher risk to develop stress fractures than were their heavier running mates.

Miller says that there is a problem among female collegiate runners because of their widely held belief that lighter equals faster. “Staying at a low weight may work for a while,” he says, “but eventually, it catches up to these athletes and they end up injured.”

Miller suggests that thin runners add lean muscle mass to support their bones. “To do this, these runners may gain weight and their BMIs will go up,” he says. “But it will help keep them healthier and in the game.”

Lt. Col. Mark Cucuzzella, a professor at West Virginia University School of Medicine, says female runners with low BMIs should be aiming to add fat to their bodies. “In this age group, body fat should be in the range of 20 percent to 22 percent for hormonal health,” he says. “If it’s not there, all the calcium and vitamin D in the world won’t heal a stress fracture.”