Grizzly bears are among North America’s most powerful animals. Known for their size, strength, and endurance, these apex predators dominate their environment with their physical capability. But just how strong are they?
Grizzly Bear vs. Human: Size & Strength Comparison
Adult grizzlies stand between 6.5 and 8 feet (2 to 2.4 meters) tall on their hind legs and weigh 400 to 790 pounds (181 to 358 kilograms). By comparison, humans average 5 feet 4 inches to 6 feet (1.63 to 1.83 meters) tall and weigh between 130 and 200 pounds (59 to 91 kilograms). So, in sheer mass, grizzlies are 2 to 4 times bigger than humans on average.
With regard to strength, humans fall well short of grizzly bears in lifting and carrying capacity. Grizzlies’ can lift or carry over 1,100 pounds (500 kilograms) with ease. Bears in the wild have been seen ripping apart logs, flipping heavy rocks, and digging through snow and earth as if they were lightweight.
Most untrained adults can lift or carry around 50 to 100 pounds (23 to 45 kilograms) briefly. The world’s strongest humans—competitive powerlifters or strongmen—can deadlift or squat between 800 and 1,100 pounds (363 to 500 kilograms) for a single lift. For example, Eddie Hall holds a record in the deadlift at 1,102 pounds (500 kilograms). However, this is an extreme feat and requires substantial training, specialized equipment, and often support gear. Elite humans can manage heavy weights for only short moments and under very controlled conditions.
In the wild, no human would be able to match the bear’s power and raw force for such heavy work.
Grizzly bears are estimated to be about 2.5 to 5 times stronger than an average human in terms of raw lifting and carrying power. Furthermore, their immense body mass adds force to every movement. While muscle fibers give them explosive power, it’s their massive bulk that amplifies that power. This makes actions like moving large rocks feel easy for them.
Grizzly Bear vs. Human in a Fight
There’s no contest. In a physical fight, a grizzly’s strength, speed, and power would overwhelm any human. Accounts of grizzly attacks show that the bear’s superior strength leave humans little chance of survival in a confrontation. Juvenile grizzlies alone demonstrate more strength than an average adult human.
A grizzly bear’s swipe, equipped with 4-inch claws, carries enough force to disable most animals in a single hit. They have a bite force over 1,000 pounds per square inch (PSI), more than double the bite strength of an average human. They can tear through flesh and even crush bones. Grizzlies have dense fur, a thick hide, and layers of muscle and fat that act like natural armor. They have been observed enduring blows from other large animals and even attacks from other bears without significant harm. Therefore, a human could not realistically deliver a strike hard enough to hurt a grizzly bear.
Despite their size, grizzlies are also fast, reaching speeds of 35 mph (56 km/h). Humans would not be able to outrun a bear.
Why So Strong?
Grizzlies evolved for a life of physical dominance. As opportunistic omnivores, their survival depends on their ability to access a wide variety of food sources. They dig through frozen soil, scavenge from other predators, and defend their kills from competitors like wolves or other bears. In environments with scarce resources, strength ensures survival, whether it’s protecting a territory or securing a mate. Over millennia, these pressures have made the grizzly into one of the strongest land animals.
A grizzly bear’s muscles are packed with fast-twitch fibers, which are specialized for short bursts of explosive power. In addition, their muscles are extremely dense and massive compared to their body size. Their skeletal structure, tendons, and ligaments are all built to support its immense strength.
In contrast, humans evolved with muscles dominated by slow-twitch fibers, which are better suited for endurance-based tasks such as long-distance walking or running.
Studies on Grizzly Bear Strength
Montana State University’s mechanical engineering students collaborated with National Geographic to measure the strength of a grizzly bear compared to a human. The test centered on Brutus, a trained grizzly bear raised in captivity, who participated without harm. Engineers designed a custom rig that measured force applied by the bear. It included a steel bar connected to sensors capable of recording precise pressure data.
Brutus was encouraged to push or pull the bar, mimicking natural behaviors like pawing or swiping. Human participants then tested the same setup. The results were staggering. Brutus generated forces exceeding 1,200 pounds without maximum effort, far beyond what the strongest humans could produce. Another test involved a 700-pound metal dumpster, which Brutus could effortlessly tip over onto its side.
After two days of testing, the team concluded a grizzly’s strength is equal to 2.5 to 5 humans.
