Benign paroxysmal positional vertigo in mountain bikers.

We evaluated 4 men who had benign paroxysmal positional vertigo (BPPV) that occured several hours after intensive mountain biking but without head trauma. The positional maneuvers in the planes of the posterior and horizontal canals elicited BPPV, as well as transitory nystagmus. This was attributed to both the posterior and horizontal semicircular canals (SCCs) on the left side in 1 patient, in these 2 SCCs on the right side in another patient, and to the right posterior SCC in the other 2 patients.

Motion measurements in the jumping of a mountain bike.

Mountain biking is generally a much more extreme sport than road cycling. It exhibits large motions and loadings, and involves complicated interactions between the rider and the bike. A dynamic model of a mountain bike and rider is being developed that requires validation by comparing predicted and actual dynamic performance.