Their fat content has nothing to do with how strong an animal is, they evolved that way to combat the extreme cold they live in and to insulate them when their swimming. They do have a very different muscle structure that allows them to perform extreme feats of strength such as crushing a walrus head with one downward blow of their paw or breaking through the ice to get to the sea below. they don't attack Blue whales either, only people do that. They have extreme amounts of fast twitch muscle fibres that exist in all mammals and its fast twitch fibres that produce explosive movements such as running at great speed for a short time or punching through a few feet of ice. Slow twitch fibres are meant for endurance such as marathon running which is why runners are so lean and fast twitch fibres belong to the body builders in humans. Hope it helps.

They have some pretty strong muscles too. I doubt it could lift a 150 ton BW but it is still extremely strong and could pull a walrus over twice its size out of the water. They can run that fast as can Grizzlies. They have more muscles for running that we do. Look at a cat. My cat can jump probably 7 feet high. Carnivores typically have some well developed muscles for running.

No, I think you are confused. Polar bears have nothing to do with blue whales. They don't hunt them, they don't eat them, and they certainly don't lift them. Polar bears hunt seals, and sometimes birds and eggs, or even a walrus. A big walrus weighs 2 tons, a long way from 150 tons.

I will admit that polar bears have been known to attack beluga whales and narwhals; but these are a LOT smaller than blue whales.

Yes, they have a different muscle sctucture than us human, the samr can be observed in other predators, like big cats. The fibres in the muscle is different so they can yield much more power as in jumping, running or other activities.

They are at 50% body fat and yet they can lift a 150 Ton migrating blue whale out of the ocean to the surface with extreme ease! And plus they can run 35 miles per hour at their max! How do they do this, do any have advanced muscle structure, dense bone structure? Can any of you guys help me figure out this?