There’s a reason most elites don’t look like they spend a lot of time in the weight room. Running isn’t exactly known for building bulk. But strength isn’t just about how much weight you can lift; it also encompasses power (or how fast you can use the force you’ve built up) and the ability of a muscle fiber to do what it’s designed to do.
So does running build muscle? The short answer is yes, it is possible to build muscle while running.
“With running, the majority of the muscle work or contraction is eccentric, which is the hardest load on the body,” explains Joe McConkey, a Boston-based exercise physiologist and USATF-certified running coach. Eccentric contractions occur when a muscle lengthens—not shortens—under load or tension. For example, during the lowering phase of a squat, the quadriceps (front of thigh) muscles eccentrically contract.