Refresh data from a joined spreadsheet

[MikeBeyer]

I have joined an excel spreadsheet to a polygon feature class. The data in this spreadsheet changes based on a model we are running in Excel. I would like to have GIS show updated data when I update the model withouth having to break and re-form the join each time.

Is there a way to do this? I have tried refreshing the data, but it does not seem to empty the copied values and refresh joined attributes.

Thanks for any help you can provide

[MarcinGasior]

When you join an Excel table to layer, an Excel spreadsheet is locked to write so you cannot save changes if ArcMap is running.

Try to save your ArcMap project, exit ArcMap and then run your Excel model and save spreadsheet.
When you open your ArcMap project, values from the joined Excel table should be updated.