Muscularize is an active verb that means to develop, strengthen, or give more emphasis to something. However, when searching for suitable synonyms, it becomes apparent that there are limited options available. An alternative term would be "strengthen", encapsulating the idea of reinforcing or making something stronger. "Develop" is another appropriate replacement, suggesting the growth and improvement of a particular aspect. Additionally, one could use "fortify" to indicate the process of making something more robust or sturdy. While the options for synonyms may be somewhat restricted, by utilizing these alternatives, one can still effectively convey the notion of muscularizing a concept or object.