It has been shown that having intellectual disabilities impacts to reduce performance compared to athletes without this impairment. However, it has also been demonstrated that there is a not a direct link between intelligence and athletic performance. To advance elite ID sport more needs to be understood about the relationship between this impairment and sporting performance. This is vital if competition classification systems are to be based on theory and evidence. This study used the International Classification of Functioning, Disability and Health (ICF) as an approach to classification and examined the impact of multiple health problems on athletic performance. A health survey was administered to two groups of athletes with ID: elite and regional level athletes. Athletes with Down Syndrome were also identified. Overall disability scores predicted sporting performance, but not IQ or Down Syndrome. The implications of these findings are discussed with reference to the ICF framework and classification.