The phrase "most exercised" can be replaced with a variety of synonyms to convey the intended meaning. Some alternatives to consider are "most active," "most used," "most engaged," "most practiced," and "most utilized." These phrases can be applied in different contexts, such as describing the most active muscles in the body, the most commonly used words in a language, the most engaged employees in a company, the most practiced techniques in a sport, or the most frequently utilized tools in a trade. Choosing the right synonym to replace "most exercised" depends on the subject and purpose of the sentence.