If you're already strength training, doing more sets and reps doesn't always mean your arms and shoulders will grow much bigger—other things like rest, diet, and genetics also play a big role.

Some people’s muscles grow a lot with training, others don’t—but if one person’s arms grow, their legs usually grow similarly, meaning your body’s natural response is more important than which muscles you train.

Some people’s muscles grow a lot with training, others don’t—but if one person’s arms grow, their legs usually grow similarly, meaning your body’s natural response is more important than which muscle you train.

Getting stronger from lifting weights doesn’t always mean your muscles are getting bigger—and vice versa. Strength and size don’t go hand in hand.

Getting stronger from lifting weights doesn’t always mean your muscles are getting bigger—and vice versa. Strength and size don’t go hand in hand.

If you're already strength training and you do more sets of bicep exercises each week, your biceps tend to get thicker — and this link isn't just luck, it's a real pattern.