If you're like us, you blame most of your boob issues, such as pain or changes in size, on your period. And it's true, that can be why your boobs feel sore or look bigger. But different stages of your menstrual cycle can affect your breasts in different ways, and other factors—diet, medications, and certain activities—can influence your dynamic duo too. Exercise In general, you're unlikely to notice any changes in your breasts even with an intense weightlifting regimen. That's because your breasts sit on top of the pec muscle, but aren't part of them. So you can develop stronger muscles underneath your breasts without affecting their size or shape, says Melissa Crosby, M.
Breast exams help doctors check that everything's normal. During a breast exam, a doctor or nurse practitioner will feel a woman's breasts to check any lumps and bumps and see if there are changes since the last exam. Doctors don't usually start doing breast exams until a woman is in her 20s. Why Do Girls Need Them? Most teens don't need breast exams.