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Introduction: Given the rapid changes in the country's population pyramid towards aging, planning strategies and techniques that slow down this process should be a focus for health planners. One of the most effective measures is the development of water sports and hydrotherapy. Therefore, the aim of this research was to identify and rank the factors affecting social marketing in the development of exercise in the water and hydrotherapy among the elderly in Tehran.
Methods: The statistical population of the study was all elderly people visiting private swimming pools in 22 districts of Tehran in 2023. Considering the determination of sample size for an unlimited population, using the Cochran formula, the number of 384 people was specified. Two questionnaires were used to collect data: the Lifebour (2010) social marketing questionnaire and a researcher-made questionnaire on exercise in the water and hydrotherapy development. The reliability and validity of the tools were confirmed using factor analysis. Path analysis method and Friedman test were used to analyze the data and rank the factors.
Results: Based on the path analysis results, it was determined that social marketing had a positive and significant effect with a coefficient of 0.452 on the development of hydrotherapy and exercises in the water (path coefficient = 0.38, t-value = 2.231), and all social marketing components were influential on hydrotherapy development. Also, based on the results of the Freeman test, the customer orientation component had the highest priority with a score of 4.19 and the social marketing mix component had the lowest priority with a score of 3.72.All calculations were at the 95% confidence level.

Conclusion: Given that social marketing seeks to adopt a new behavior in society, exercising in water and hydrotherapy should be considered a value for the elderly. Also, since all components of social marketing were effective, it is necessary for planners to pay attention to all components simultaneously in order to be effective in attracting and retaining the elderly.