Rather than him extending his shoulders forward while walking... Perhaps Batman can help you out.
![](https://castlevaniadungeon.net/forums/proxy.php?request=http%3A%2F%2Fwww.animateit.net%2Fdata%2Fmedia%2F207%2Fbatman6.gif&hash=dac55dc5351ac132f41069c4f340c33a)
Reference the way his arms and chest are moving. It'd give it a more... natural, but still powerful, walk.
NOTE: Yes, I'm aware you can't see his boots and gloves and cape all too well.