In the early days of motorsports, motorcycle racing on board tracks was a fast, popular and dangerous sport. The board tracks were just that, boards layed edge up and tightly packed with steeply banked turns. The wood, as wood will, tended to splinter under the stress of the races and huge splinters often impaled the riders. I hate to think what happened to the unfortunate riders who went down on the track - more than road rash involved there.