Inversion are used on the left hand between chord changes. Let's say a pianist is play a song in the key of C. Since the three main chord changes for the key of C are C, F, & G, the pianist will be switching the left hand back and forth between those chords. If the pianist used the first inversion for each chord witht the left hand while chording, he/she would be playing:
C-E-G for the C Chord
F-A-C for the F Chord
G-B-D for the G chord
When looking at the keyboard you will notice that moving from the C chord to the F chord is quite a jump. In fact, you would have to go pass the notes D, and E to get to F. So when changing from the C chord to the F chord, since chord changes happen quickly, the pianist could move from the first inversion of C chord to the third inversion of F chord. That way the pinkie finger on the left hand could remain on C and only the E-G would move up one note each to F-A like this:
C-E-G - first inversion of C chord
C--F-A - third inversion of F chord
That's a comfortable switch without having to move all the fingers four notes higher like you would if you switched from the first inversion of C chord to the first inversion of F chord.
Using this technique, one can make chord changes with the left hand nice and smoothly applying this to all chord inversions and using the inversion of the next chord close to the current inversion you are playing.
Matthew Stephens
www.thepianobyear.com
Meet Matthew Stephens by visiting his website at http://www.thepianobyear.com
Source: www.ezinearticles.com