October is full of pink ribbons and screening reminders. Those matter. But one part of the conversation gets less attention: regular physical activity is linked to a lower risk of breast cancer. Exercise isn’t a guarantee, and breast cancer is never proof that someone didn’t take care of herself. Here’s what the research shows, what it doesn’t, and how to use it in a way that helps instead of adding pressure.

San Francisco makes it easy to count walking as exercise. We walk to BART, climb hills, carry groceries home, and take the stairs because the elevator is taking too long. All of that movement matters. But if walking is the only exercise you do, one important piece may be missing: strength training.