Wearing headphones and walking to the beat of booming bass lines may be a relief after lectures, but has proven to be dangerous and, in some cases, deadly.

A new study by researchers at the U. Maryland School of Medicine looked at pedestrian injury data from 2004 to 2011 and found 116 deaths or injuries that occurred nationwide to pedestrians walking while wearing headphones.

“There’s a lot said about distracted drivers talking on phones and texting, but not much is said about pedestrians wearing headphones,” said Richard Lichenstein, the study’s leading author and director of pediatric emergency medicine research at the U. Maryland Hospital for Children.

The study, which was published last week in the journal “Injury Prevention,” found that most of the crashes involved trains and that 90 percent were in urban areas. The study also found that 68 percent of victims were male, and 67 percent  of victims were under the age of 30.

While injuries and deaths from distracted walking are increasing, so are sales of music players. For example, iPod sales have increased rapidly in the last two decades, going from 600,000 in 2002, to 275 million in 2010. Lichenstein noted that 74 percent of teens own an MP3 player.

The researchers think two factors may explain why pedestrian headphone use can be dangerous: multitasking and environmental isolation.

Wearing headphones while walking is an example of what Lichenstein called “inattentional blindness,” where the brain cannot pay attention to other objects like traffic while listening to music. A warning sound, such as a horn, was sounded in 29 percent of the crashes.

“You can enjoy your music, your podcast, but keep the volume low, and be aware that you can’t really multitask,” Lichenstein said. “Nothing is that important in the big scheme of things than getting to where you want to go safely.”

Lichenstein pointed out that drivers involved in the crashes could have been distracted as well. He plans to continue researching the topic to get a better picture of the risks associated with pedestrian headphone use.