ANN ARBOR—University of Michigan researchers will look at childbirth as an athletic event in order to develop guidelines for women who want to start running again after having a child.

“During childbirth, there are injuries to the body that are like any other athletic trauma, but we don’t treat them that way,” said avid runner Jessica Deneweth, assistant research scientist and director of the Michigan Performance Research Laboratory. “These women are athletes, but very little is known about how to get them back to the level of physical activity where they used to be.”

In the first known study of its kind, researchers from the U-M School of Kinesiology will track gait biomechanics, foot and body morphology, general health and physical activity habits of runners through and after pregnancy.

The study is currently seeking participants ages 18-40 who were regular runners before getting pregnant, are considering getting pregnant, are currently pregnant, or are less than six weeks post-birth.

“We know that exercise in general is very important to physical and mental-well being and running is great because it’s low barrier-to-entry, and a stroller can be pushed,” Deneweth said. “But many women say they can’t start running again after childbirth because of pain or discomfort, and physicians are frustrated because they don’t have return-to-play guidelines or rehabilitation advice to give patients.”

Changes during pregnancy and birth force women to move differently and put stress on the joints and soft tissue, making running challenging, Deneweth said. Some of these include pelvic widening, stretching of the abdominal muscles, weight gain and ligamentous laxity. Women often receive sprains, tears and stress fractures during childbirth that can cause poor pelvic control, incontinence and overload of other body parts due to over compensation.

“Pain-free running requires that core muscles be strong and fire in the proper patterns,” Deneweth said. “The stress of pregnancy and childbirth strongly compromises this core control, making it very hard for many women to successfully return to running.”

Deneweth said female runners are hungry for information about postpartum injury, and points to the baby-belly photos that professional marathoner Stephanie Rothstein Bruce shared online and instantly went viral.

Bruce has diastasis recti, a separation of the abdominal muscles during pregnancy, and her photos showed her startlingly slack belly. Bruce struggled to regain her pre-baby speeds and, ultimately, didn’t qualify for the 2016 Olympic team, Deneweth said. This potentially serious but common injury can happen during labor or if a woman returns to running too early, Deneweth said.

In another study, U-M nursing researchers used magnetic resonance imaging to diagnose injury and track healing time in pregnant women at high risk for pelvic muscle tears.

They found that a quarter of women showed fluid in the pubic bone marrow or sustained injuries similar to a sports-related stress fracture, and two-thirds showed symptoms that indicate a severe muscle strain. Forty-one percent sustained pelvic muscle tears, with the muscle detaching partially or fully from the pubic bone.

More information:

• Jessica Deneweth
• Michigan Performance Research Lab
• Related news story: Childbirth an athletic event? Sports medicine used to diagnose injuries caused by deliveries