This Narragansett Brewery ad appeared in the 18th edition of the R.I. Medical Science Monthly in 1892. They advertised the medicinal qualities of their Lager Beer. Only in business for two years, this was well before Prohibition. If you read the caption they state it was used as an invigorator. Which means it gave the patient strength. Oh you mean "beer muscles." Here's what the caption reads:
PHYSICIANS all over New England who have occasion to prescribe Lager as an invigorator, appreciate the fact that the lager brewed at the Narragansett Brewery of Providence, R.I., since its establishment two years ago, has enabled them to obtain a truly pure and decidedly wholesome beer for their patients. The Malt and Bohemian Hops used in this Lager are the best that is possible to obtain. This, with the purest spring water, scrupulous cleanliness and a most thorough process of fermentation, makes it highly desirable for medicinal purposes. Physicians and professional men are cordially invited to inspect the plant and process.