The aim of the present study was to analyze the reasons for practicing PA among university students in the Ecuadorian context, determine the differences according to sex and work-study compatibility, establish the association between the reasons for practicing PA, and estimate the predictive value of sex, age, and work-study compatibility on the reasons for practicing PA. The sample consisted of 1412 university students (21.2 +/- 3.5 years), 513 men (36.3%) and 899 women (63.7%). The instrument used for data collection was the Goals in Exercise Content Questionnaire. The Mann-Whitney U test, Spearman's correlation coefficient and a linear regression analysis were used to analyze the results. The main findings show that there are statistically significant differences between men and women in the reasons of social affiliation, health direction, social recognition and skill development. Also, statistical differences are observed between women who do or do not combine study and work in the reasons of social affiliation, social recognition and skill development. On the other hand, the main motivation for PA is health, while the motive that least encourages the practice of PA is social recognition. Finally, in the regression analysis, sex presented a significant predictive value in the motives analyzed. Therefore, the interests of Ecuadorian students are revealed, and key information is obtained to improve and increase the levels and adherence to PA in order to contribute to a more physically active life in the university population.