AFAIK, your choices, as far as "general impact resistance", are either in-mold or injected foam - basically, one-time-hit that doesn't do much for small hits but takes a hard hit well versus meant to the small hits regularly but doesn't do as well in a hard hit.

You toss both after a good hit, but the former is lighter and meant for those riding in ways that don't expect a fall but want protection in case of the worst, while the other is for skiers expecting to fall, like air or pipe skiers/snowboarders.