Biking along Chicago’s 18-mile lakefront bike trail may be fun, but it leads to frequent accidents and injuries, according to a story in the Chicago Sun-Times (August 9, 2009). The bike path, while great, is sometimes so crowded that it’s hazardous. People collide and swerve to avoid hitting rough patches. Chicago lifeguards reported 126 wipeouts between 2002 and 2008.

Wearing a helmet doesn’t ensure safety. A biker quoted in the story was wearing a helmet when he swerved to avoid a pedestrian. Without the helmet, doctors say he would have died. He lay in a coma for a week, needed ...