First of all, it wasn't a large pack of bears or wolves attacking them. If it were, they should have run.
Never run from a bear. It's natural instinct, it will chase you.
Manti is exactly right here. For that matter, don't run from a pack of wolves, either, for basically the same reason: don't behave like prey. Wolves are usually not interested in confrontations with humans, though.
In fact it's best to not move at all, just play dead.
I have heard that advice, but I have heard other advice about bears, too. Part of the reason for that, I suspect, is that in North America, we live with two different species of bear. One is the brown bear,
Ursus arctos (of which the "grizzly bear" is a subspecies), which also lives in northern Eurasia. The other is the American black bear,
Ursus americanus. The two species differ in behavior, and therefore present different threat profiles to humans. However, their ranges overlap to some extent, and a non-expert may have difficulty distinguishing between
U. arctos and
U. americanus, especially under stress: "brown bears" are not necessarily brown, nor are "black bears" necessarily black. So, I think we Americans and Canadians often get "generic" advice that is sensible to follow if you're not sure which of the two species you've encountered.
As for me, I've only ever had to deal with black bears, in various regions of Appalachia. I could say more if anyone's curious, but I won't for now, as it's off-topic...we can be very sure that there were no American black bears in the Northern Urals in 1959