This chapter describes the physiological and anatomical consequences of an spinal cord injury (SCI), with the main aim to provide some practical information for coaches, practitioners to fully understand the hydration needs of athletes with an SCI so that they can apply their knowledge to a condition perhaps beyond their primary area of expertise. Guidance on fluid replacement is difficult to determine for athletes with an SCI, where the individual's fluid loss will depend only on the environmental conditions but on the level and completeness of the SCI and available sweating capacity. Wheelchair sport adds, layer of complexity, and athletes differ with respect to their sports classification, which consequently influences physical capacity and energy expenditure. Athletes taking part in the sports must be aware of the influence clothing can have on thermoregulation and sweat losses. As with any athlete, it is recommended that athletes with an SCI practice the hydration strategy in a training situation prior to use in competition.