Self-Perceived Quality of Life and Physical Activity Levels Through Accelerometry in Young People with Intellectual Disabilities

<b>Background</b>: The relationship of objectively measured levels of physical activity (PA) to quality of life (QoL) in young adults with intellectual disabilities (IDs) needs to be further researched. This study compares PA levels and self-perceived QoL in young adults with ID compared to those with no intellectual disability and examines whether higher levels of PA are related to better self-perceived QoL in the domains of physical, psychological, social and environmental well-being. <b>Methods</b>: A hundred young adults participated (GID: n = 50; GNID: n = 50). Demographic data were collected through questionnaires, and PA levels were measured using ActiGraph GT3X-BT accelerometers over a 7-day period. QoL was assessed using the World Health Organization Quality of Life short questionnaire (WHOQOL-BREF). An independent samples <i>t</i>-test was used to examine differences between groups (GID and GNID), and correlations between PA variables and QoL variables were calculated intra-group. The statistical significance was set at <i>p</i> ≤ 0.05. <b>Results</b>: The GID scored significantly lower in social (<i>p</i> = 0.001, d = 0.67), environmental (<i>p</i> = 0.007, d = 0.56) and total QoL (<i>p</i> = 0.015, d = 0.51) domains, and showed lower light PA (<i>p</i> = 0.042, d = 0.45). No significant PA-QoL correlations were found in the GID, while vigorous PA correlated positively with physical QoL in the GNID (rho = 0.35; <i>p</i> = 0.028). <b>Conclusions</b>: Self-perceived QoL values, as well as PA levels, are lower in young people with ID, with significant differences observed in the social and environmental domains, and in light PA. No associations were found between PA and QoL variables in the group of young people with IDs. Vigorous PA was significantly associated with the physical domain of QoL in the GNID.