Abstract
Heavy protective helmets may cause injuries to the cervical spine and fatigue of the neck muscles. A theoretical analysis was made on the reaction forces in the cervical spine caused in rapid head movements using helmets with different weights and mass distributions. An electromyographic study was made on the fatigue of the neck muscles in ice-hockey players of different ages wearing helmets in static load tests. The maximum recommended mass depends on the way and time the helmet is used and the protective requirements.