I find the best way is to double click the border between the column to fix
and it righthand neighbour; or the border between a row and it lower
neighbour
Don't know how "short" you'd consider this, but if your goal is to
adjust row heights and column widths using the keyboard instead of the
mouse, try this:
Row Heights: Alt+O, R, E
Column Widths: Alt+O, C, W