The left hand tends to be sore from prolonged holding various block chords in curled finger position (sometimes looks like eagle's talons ;-)). While large spans is hard to reach, they are less likely to require tightly curled fingers. When I watch professionals, their left hand looks very relaxed. My left hands feels and looks tense while doing block chords especially when a chord last one or two whole measures---am I supposed to use the pedal even though not indicated since the chord would have faded without a pedal before the end of the bar anyway?
Curled fingers and long duration of the chords seem to be some major causes for the sore hand. Any advice/tips how to keep the left hand relaxed?