No, you cannot change the name of the bar. In a macro or ability, you can use @{selected|bar_1} or @{target|bar_1} (or bar_2 or bar_3) to get the current value of the selected (or targeted) token's bar, as well as @{selected|bar_1|max} to get the maximum value. @selected will fail if you don't have a token selected when you use the macro. @target will prompt you to select a token when you use the macro. @selected doesn't work as you might expect if you have multiple tokens selected; only one of the tokens will be used, and the choice isn't necessarily predictable; you're better off just selecting a single token. You can name your @targets, which is useful if you want to reference the same target multiple times or reference multiple targets: @{target|Target1|bar_1}, @{target|Target 2|bar_2}, @{target|Happy Fun time Target|bar_3}. If you want to reference the |max of a @target, you must specify a name.