Sports concussion is a risk that occurs in contact sporting activities like football and rugby, as these sporting activities involve forceful contact with other players, and in which the head is vulnerable to high-speed contact, typically like heading of the soccer ball. The impact of such a blow can jar the head, possibly bruising the brain as it is shaken around within the skull. Typical symptoms of sports concussion (post-concussion symptoms) are dizziness, headaches, fatigue and concentration problems.