Boosting: Autonomic Dysreflexia in Sport
Definition and Background:
In disability sport, there is a performance enhancement method known as “Boosting,” which is when someone intentionally causes a bout of Autonomic Dysreflexia (AD) to improve athletic performance (Gee et al. 2018; Nightingale et al. 2022; Gee et al. 2015; Mills & Krassioukov 2011; Blauwet et al. 2013).
Most people with SCI, often those with injuries at T6 or above, cannot regulate blood pressure and heart rate in the same way as others (Fossey et al. 2022; West et al. 2013). Athletes that excel in sports often have superior cardiac output and/or oxygen uptake. During competition, a wheelchair athlete’s heart rate may not increase according to the body’s demands, resulting in low blood pressure, fatigue, and often a loss of endurance and poor performance.
What Happens:
Some athletes have learned that they can subvert these cardiovascular dysfunctions and increase their blood pressure and other cardiac outputs (in the short-term) by causing pain or discomfort in an area below their injury. Athletes with SCI may do this by:
- Clamping of the urinary catheter to produce bladder distension
- Excessive tightening of the leg straps
- Twisting and/or sitting on the scrotum
- Breaking their big toe before the competition
- Abdominal binders or pressure stockings on legs
Consequences:
Athletes with SCI who self-inflict physical suffering in order to improve athletic performance take tremendous health risks (i.e., hypertension, cerebral hemorrhage, stroke and sudden death).
Two case studies on boosting have shown enhanced athletic performance (Nightingale et al. 2022; Gee et al. 2018). A male wheelchair rugby athlete who had unintentionally boosted via bladder overdistension showed considerably higher average HR during 20m sprints compared to when ‘unboosted’ (Gee et al. 2018). Similarly, a male with SCI performing cardiopulmonary exercise testing (CPET) unintentionally boosted, resulting in relative tachycardia with an increase of 8.1-17.5% in peak HR (Nightingale et al. 2022). In both cases, performance was marginally enhanced; the rugby athlete sprinted faster than when ‘unboosted’ (6.7s vs 6.87s) (Gee et al. 2018), and the male performing CPET showed elevated power output (Δ19W), oxygen intake (Δ3.61 ml· kg·-1min-1) and ventilation (Δ11.4 L ·min-1) compared to when ‘unboosted’ (Nightingale et al. 2022).
In a study of 99 athletes with SCI, 54.5% had previously heard of AD while 39.4% were unaware; 16.7% (all males) had used AD to enhance performance, despite participants reporting that AD is somewhat dangerous (48.9%), dangerous (21.3%), or very dangerous (25.5%) to health (Bhambhani et al. 2010). These findings indicate the need for educational programs directed towards enhancing knowledge on AD in rehabilitation professionals, coaches, and trainers working with individuals with SCI (Bhambhani et al. 2010).
The International Paralympic Committee considers AD doping and has banned its use. Any deliberate attempt to induce AD, if detected, will lead to disqualification from the sporting event and subsequent investigation by the IPC Legal and Ethics Committee.