A researcher involved in a groundbreaking concussion study -- one that outfitted 21 varsity football players with helmet sensors and monitored every collision -- will be in St. Louis Park Tuesday to talk with coaches and parents.

Purdue University's Eric Nauman was the lead author of a study that revealed last fall that multiple hits could diminish cognitive skills in football players -- even if they never suffered actual concussions. The finding was not the intent of the study -- which was designed to examine the impact of concussions -- but was the surprising conclusion as supposedly uninjured players faltered on memory tests.

Nauman was invited by a local Purdue alumni association. His talk is scheduled for 7 p.m. May 17 (Tuesday) at the St. Louis Park High School main gym. The event is free, though a $10 donation to a scholarship fund is requested.

The lecture is but one of several concussion-related items in the news this week, including the death of former Wild hockey player Derek Boogaard and his family's decision to donate his brain to concussion-related research. The Minnesota legislature is expected this week to take up a bill that would toughen concussion regulations for high schools and recreational sports clubs.

Researchers at Purdue are trying to develop a football helmet that reduces the collective damage of multiple blows to the head. Nauman's team is trying to determine how many routine hits cause damage.

"We're not yet sure exactly how many hits this is, but it's probably around 50 or 60 per week, which is not uncommon," Nauman said in a Purdue news release. "We've had kids who took 1,600 impacts during a season."

The force from many of these hits ranges from 20 Gs (20 times the force of gravity) to 100 Gs. By comparison, riding a roller coaster causes 5 Gs and heading a soccer ball causes 20 Gs.

The risk of concussions isn't resigned to football. One study of NCAA sports found the risk highest in women's hockey. A bill awaiting action by the state House and Senate would set strict limits on when concussed athletes could return to play in all youth sports and require coaches to take online concussion training. Opposition from school and civic groups over liability was addressed by a revised version of the bill. A House vote may come later this week.

Youth hockey officials locally and nationally have considered removing body checking from certain age levels to mitigate the risk of concussions. Minnesota Hockey also has issued substantial concussion guidelines.