Boosting in Elite Athletes with Spinal Cord Injury: A Critical Review of Physiology and Testing Procedures

Abstract

Many individuals with spinal cord injury (SCI) experience autonomic dysfunction, which can have major implications on heart rate and blood pressure responses to exercise, and consequently athletic performance. Athletic performance may be improved by the induction of autonomic dysreflexia (‘boosting’), a dangerous and sometimes life-threatening condition. Here, we review the autonomic response to exercise in individuals with SCI and the current testing methods for boosting, and examine the potential for autonomic testing to be used in the classification of SCI athletes. Given the difficulties associated with researching the effects of boosting, only three studies have compared the physiological performance of elite athletes in the boosted and unboosted state. These studies found athletes had an improved performance of ~7 to 10 % in the boosted state. Blood pressure, heart rate, oxygen consumption, and circulating catecholamines were also higher in the boosted state. Although 27.1 % of athletes believe that boosting was common in their sport, no athlete has ever tested positive for boosting at an event sanctioned by the International Paralympic Committee. Athletes with SCI competing in sports that have a high cardiovascular demand/aerobic component may experience the greatest benefit of boosting. Boosting improves athletic performance even at blood pressure levels well below the current threshold for disqualification set by the International Paralympic Committee, a level at which individuals with SCI are putting their health and lives at serious risk.