Their cases share a common thread -- repeated concussions, sub-concussive blows to the head, or both.

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The act of an offensive lineman hitting a defensive lineman on every play produces a low level concussive hit.

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Seau suffered sub-concussive and concussive blows to the head in the NFL, sometimes lacerating his face, court papers said.

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As well as a concussive punch, Shavers possessed the other quality given to the most exciting fighters in history - a suspect chin.

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"Junior had wanted to donate his brain to science to the study of concussive injuries, " he told CNN affiliate KGTV of San Diego.

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Thus set up, the RX F Sport has a relatively zingy and concussive ride, just enough to upset one's aim with the Remote Touch controller.

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Simply multiply the number of plays and collisions and it is possible that a player will retire from football with 10, 000 or more low-level concussive hits.

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Any time the revs rise past the thresholds for the exhaust bypass valves, the Aston's sound transforms from a somewhat truck-y thud to a concussive, fiery staccato.

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When an offensive lineman hits a defensive lineman to begin the play in football a low level concussive hit occurs and the brain of each player is impacted.

FORBES: The Death of the NFL

The adaptive dampers' response ranges from flinty to flintier, and stiffer springs, lightweight aluminum knuckles, and revised rear-end geometry give the XKR-S a bright, concussive ride that would pound commuters to dust.

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