Keep Scale While Animating I am quite sure I've seen someone to disable scale change when animating, for an instance if I enable FK / IK and drag my hand to change position it will stretch like so:

 


I would like to know how can I fix that. (no scripting)
This isn't the scale, but the IK stretch feature, which you can control from the properties panel (N shortcut key). The following video explains how to use this property to control stretching:
http://youtu.be/AII-n2GHbG4