1 Cyberpsychology Laboratory and Department of Psychoeducation and Psychology, Université du Québec en Outaouais (UQO,Campus de Saint-Jérôme), Saint-Jérôme, Canada.
2 Substantive-Methodological Synergy Research Laboratory, Department of Psychology, Concordia University, Montreal, Canada.
3 Optentia Research Unit, North-West University, Vanderbijlpark, South Africa.
4 School of Education, Translational Health Research Institute, Western Sydney University, Sydney, Australia.
5 Department of Physical Activity Sciences, Université du Québec à Trois-Rivières, Trois-Rivières, Canada.
6 Institute for Positive Psychology and Education, Australian Catholic University, Sydney, Australia.

The main objective of this person-centred study was to identify profiles of actual and perceived physical fitness among a sample of youth with intellectual disabilities (ID). Participants were 377 youth (60.4% boys) with mild (49.6%) to moderate (50.4%) ID recruited in Australia and Canada. Latent profile analyses revealed five profiles: (1) Underestimation of Average Physical Fitness (5.5% of the sample); (2) Moderate Overestimation of Low Physical Fitness (17.7%), (3) Moderate Underestimation of Average Physical Fitness (31.3%); (4) High Overestimation of Average Physical Fitness (28.3%); and (5) Moderate Underestimation of High Physical Fitness with an Accurate Estimation of Average Flexibility (17.2%). Profiles 1, 2, and 3 relatives to Profiles 4 and 5 included younger participants, more participants with moderate levels of ID, and participants with a higher body mass index. Additionally, profiles 1 and 3 also included a higher proportion of youth pursuing externally-driven motives and less frequently involved in sports outside of the school. In sum, our findings showed that the tendency of youth with ID to rely on upward or downward-lateral social comparisons may have resulted in a depreciation or overestimation of their low levels of physical fitness.