It's worth noting that earlier on in Guardians of the Galaxy, one of the The Collectors slaves is able to hold the Power Stone for a limited amount of time, before it destorysdestroys her.
Also, later on we see that Peter Quill (with some help from his team mates) is able to hold and even use the Power Stone, indicating that it isn't neccessarily physical strength that allows the user to hold the Power Stone.
It is my belief that Ronan would have been destroyed by the Power Stone if he had of held it for much longer, which is why he embedded it into his hammer. This is mostly based on the reasoning I give in my answer to another question here, which uses the fact that Asgardians seem to be cautious when handling Infinity Stones and that Kree are roughly as strong as Asgardians.