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Biology

Muscle Leverage

Quick fact

Most muscles in the human body act as third-class levers, which trade force for speed and range of motion—meaning you can move your hand fast, but you can't lift as much as the muscle could theoretically handle.

Why this is interesting

Ever wonder why your biceps can easily curl a weight, but your calf muscles can lift your entire body? The answer lies in the clever leverage built into your skeleton.