Recently, the Australian Football League (AFL) was rocked when it was revealed a Geelong player with a history of concussion had been asked to waive his legal rights to claim for any future brain trauma.

Read more: A secret waiver but no punishment: the AFL’s concussion conundrum just got murkier

It was the latest in a series of concussion issues the AFL has had to address in recent years.

But the focus on concussion is problematic. Indeed, concussions are not necessarily the most pressing issue in contact sports when it comes to brain injuries.

The bigger concern should be chronic traumatic encephalopathy (CTE).

CTE is a neurodegenerative brain disease that has been linked to contact sports such as Australian football, rugby league, rugby union and soccer.

It often strikes later in life but has been diagnosed in athletes as young as 20 in Australia.

It can only be diagnosed posthumously.

CTE develops after repetitive brain trauma – research indicates concussions may not necessarily be the primary cause. Instead, repeated subconcussive impacts to the brain is where the actual risk lies.

Read more: Little hits in sports may be just as dangerous as concussions – and can lead to brain damage

These subconcussive impacts, which rarely cause any symptoms, can occur during normal game play from actions such as tackling or bumping.

It is the accumulated damage from these repeated subconcussive impacts that can........

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