Marathon runners may be preoccupied with shin splints, chafing and blisters on race day, but they should also consider bladder health, a U.S. researcher says.

"The added stress on the body that comes with running a marathon can cause urinary stress incontinence problems during the race or down the road," Dr. Melinda Abernethy of the Loyola University Chicago Stritch School of Medicine, said in a statement. "People who already suffer from incontinence also are at risk for bladder-control issues while running."

Stress incontinence - the loss of urine from physical activity such as coughing, sneezing and running -- is the most common form of urinary incontinence, and affects women more often than men.

Researchers at the Loyola University Health System plan to survey Chicago area runners to study the relationship between long-distance running and pelvic floor disorders, Abernethy said. Until more is known, Abernethy recommends runners monitor their fluid intake and go to the toilet at least every few hours during a marathon.

"Putting off going to the bathroom during the race is not healthy for your bladder," Abernethy said. "Runners also should avoid diuretics, such as coffee or tea, before the race, because this can stimulate the bladder and cause you to visit the bathroom more frequently."

Abernethy added pelvic floor exercises such as kegels, may help runners prevent urine leakage during the race.