King-Devick Test in Wheelchair Sports: Identifying Normative Values and Effects of Exertion on Outcomes

Abstract

Objective: To establish normative baseline values on the King-Devick (KD) Test for contact wheelchair sport participants. The secondary purpose was to examine the effect of physical exertion on test score. Design: Quasiexperimental. Setting: Competitive disability sport venues before practices or games. Participants: One-hundred 43 wheelchair rugby or wheelchair basketball (WBB) players completed the study. Participants were predominantly men (87.5%) and played WBB (84%). Intervention: 30-m wheelchair sprint test to fatigue. Main Outcome Measure: King-Devick Baseline Score. Results: Mean KD baseline score was 59.16 6 15.56 seconds with significant differences (P , 0.05) identified by sport and impairment type, but not sex. Athletes with spina bifida and cerebral palsy had significantly higher mean baseline KD times than athletes with spinal cord injury. KD scores improved by 3.5% in athletes who reported "light" to "somewhat hard" exertion (RPE 5 13). In a subset of athletes who performed sprints until an RPE of 18 was reached, 8 of 12 players (66.7%) demonstrated an improvement in KD score; however, large increases by a few participants caused the noticeable change. Conclusions: Normative values for wheelchair contact sport athletes are meaningfully slower than able-bodied sports participants. KD score improved with exertion with the greater improvement after moderate-intensity compared with vigorous-intensity exercise. These findings can be applied clinically to monitor athlete safety.