Based on first-year results of a two-year study, researchers find helmetless-tackling drills is effective in reducing head impacts by 28 percent in one season. The innovative technique alters tackling behavior and is meant to reduce risk of head injury.

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Based on first-year results of a two-year study, researchers find helmetless-tackling drills is effective in reducing head impacts by 28 percent in one season. The innovative technique alters tackling behavior and is meant to reduce risk of head injury.