Even a light blow to the chest - equivalent to being hit by a cricket ball - could cause a fatal heart attack.

However, scientists are now a little closer to understanding what causes these freakish sporting deaths.

An article in New Scientist reveals that a ball must hit the unlucky person at exactly the wrong point in their heartbeat cycle for death to ensue.

Chest protectors worn by sportsmen offer little protection, it is claimed.

Read entire article here.