Does muscle growth cause stretch marks?

Yes, muscle growth can sometimes cause stretch marks.

When muscles grow rapidly, the skin may not be able to keep up and stretch marks can form. This is more common in people who are gaining muscle very quickly, such as bodybuilders or athletes. Stretch marks can also occur during pregnancy, when the belly skin stretches to accommodate the growing baby.

Stretch marks are usually not painful, but they can be unsightly. There are a number of treatments available for stretch marks, including creams, lotions, and laser therapy.