[Cycle ergometers in rehabilitation medicine: technical characteristics and selection criteria]

The cycle ergometer is a commonly used means of testing and training patients with energetic disabilities (particularly in the area of cardiopulmonary diseases). Recent evidence suggests that cycle ergometers can also be useful in patients with subacute and chronic stroke, brain injury, chronic degenerative neurological conditions, and in spinal cord injury. Commercially available cycle ergometers show wide differences in terms of structure and function that have a direct impact on the specific rehabilitation protocols. The aims of this review paper are: a) to briefly review the physiology and biomechanics of exercise on a cycle ergometer; b) to review and discuss the technical specifications of the cycle ergometers suited to rehabilitation settings; c) to provide guidelines for selecting appropriate cycle ergometers for the different categories of rehabilitation patients. First, the physiology of exercise on the cycle ergometer and its biomechanical features are discussed, including the patterns of muscular activity during down- and up-stroke. Upright and recumbent ergometers and their specific clinical indications are compared. Finally, the technical characteristics of the cycle ergometers (load, motor, resistance, flywheel, belt, resilience, pedals, frame, display) are described and the specific requisites for the different patient categories undergoing rehabilitation are discussed in detail. Finally, guidelines are offered for identifying the main technical requisites for appropriate cycle ergometer selection in the different disabilities.