Football players as young as 7 sustain hits to the head comparable in magnitude to those absorbed by high school and adult players, and most of the hits are sustained in practices, not games, according to research to be released Wednesday.

The findings, which may influence how youth football organizations handle training methods and rules, were included in four studies published by researchers at the Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences. The research, though limited, is considered by experts to be a step in the effort to address the relatively shallow understanding of the potential long-term effects of head trauma on young players.

More than 25,000 football players from 8 to 19 years old are taken to emergency rooms seeking treatment for concussions every year, but most of the research on head injuries in football has focused on professional and college players.

The new research, which was presented at the annual Biomedical Engineering Society conference this week, tracked about 120 players in Virginia and North Carolina from 7 to 18 over two seasons. Each young athlete wore six devices, known as accelerometers, in their helmets to measure the force, position and direction of the hits, and every practice and game was videotaped to determine how they occurred.