According to the Self-Determination Theory, perceived job pressures can coerce professionals to develop more controlled motivations towards their work, and consequently increase the probability of using controlling motivational strategies. This study sought to analyze work-related motivations as mediators between two types of perceived job pressures: organizational constraints and perceptions of clients’ controlled motivation and the use of controlling motivational strategies by exercise professionals. Using a cross-sectional design, involving 366 exercise professionals (172 women), mediation paths were assessed following Preacher and Hayes statistical procedures. Models were adjusted for gender, work experience (years), and the internal tendency to feel events as pressuring. Organizational constraints were associated with lower autonomous motivation for work and the use of controlling strategies. Perceptions of clients’ controlled motivation were associated with work-related amotivation and the use of controlling strategies. Amotivation mediated the association between organizational constraints and controlling strategies. Overall, results support theoretical predictions and previous research, extending it to the exercise domain, highlighting the interplay between job pressures, work-related motivations, and the use of controlling strategies. The understanding of what influences exercise professionals’ motivation, and consequently the motivational strategies they use, is of paramount importance for exercise promotion and the benefit of those who seek their expert guidance.