I haven't tried actively bending them with my hands, but did hook them over an extra-thick sofa back and kept them there while not using them at first.
I don't know if the band has a metal strip inside which could be bent, or is just plastic, which could snap. If the latter, perhaps heating it with a hairdryer while clamped around something a bit wider than you head (and leaving it to cool) could do the trick, but it's all at your own risk, obviously.
On the other hand, your head could be smaller than mine and you'll have no worries.
I have a big head, according to my wife anyway
Thanks again for the info!