The aim of this work is to analyse the commitment to running among urban runners by identifying groups regarding commitment to this sport and by defining their sociodemographic profile and their sports habits. A sample of 1806 participants in popular urban races in the city of Valencia was interviewed using an 11-item questionnaire on commitment to running, sociodemographic characteristics, and sports habits. The psychometric properties of the running-commitment scale allowed for the identification of two factors in commitment to running: enthusiasm for running (6 items) and affliction from running (5 items). Subsequently, a cluster analysis combining hierarchical and non-hierarchical methods was performed, identifying three groups of runners: highly committed (n = 650), moderately committed (n = 749), and slightly committed (n = 407). Highly committed runners positively rate all aspects of running enthusiasm (M = 4.15), while moderately committed runners show a more neutral attitude (M = 3.41) and slightly committed runners disagree on these aspects (M = 2.41). Both highly (M = 1.32) and moderately (M = 2.04) committed runners disagree on the affliction-related aspects of running, while slightly committed runners show a trend towards neutrality on some affliction indicators. The variables referring to age, level of studies, sports habits, and running addiction contributed to differentiating the identified groups.