Is he as strong as he looks?
Is he as strong as he looks? (Photo: Istvan Csak via Shutterstock)

How Is Muscle Strength Related to Size?

Is it possible to be strong without having big muscles, or to be huge but not very strong?

Is he as strong as he looks?

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“If I have an increase in my muscle cross sectional area, I will also have an increase in muscle strength, it just might not be proportional,” says Dr. Robert Buresh, an assistant professor in Kennesaw State University’s Department of Exercise Science and Sport Management. In other words, you’ll be stronger if you have more muscle—but will you be 100 percent stronger if you have 100 percent more muscle? Not necessarily. 

Often, people who start weight training regimens see enormous gains in strength right off the bat, but not in muscle size. “Someone in a 12- to 15-week training program might undergo a 25- to 30-percent increase in strength—or even more—and a relatively small, maybe five-percent increase in muscle size,” Buresh says. That’s because that initial strength gain is mostly neuromuscular. You’re training your brain to communicate more efficiently with your muscles, enhancing speed, endurance, and dexterity.  

So what if you keep strength training? “You will get stronger, and generally you will get bigger,” Buresh says. “But the strength increase is a lot more certain than the size increase, because there is a relatively strong genetic component” to muscle size. “People that have a higher percentage of fast twitch muscle fibers have a greater capacity to produce more force,” Buresh says. Fast twitch fibers also have a greater potential to get big.

THE BOTTOM LINE: Yes, it is possible to be strong—and to get stronger—without having enormous muscles. But it’s likely impossible to be huge and weak because big muscles will always have a lot of strength potential. So don’t go picking a fight with the meathead at your gym; he can probably body check you clear into the treadmill section.

Lead Photo: Istvan Csak via Shutterstock