Last summer, while I was out for my daily run in Berlin’s Tiergarten, I couldn't shake the feeling that something was off. My chest felt tight, and I was breathing heavier than usual. That day, my smartwatch buzzed incessantly, alerting me to elevated heart rates. In that moment, I realized how critical real-time heart monitoring could be—not just for athletes, but for anyone. It made me ponder: what if clothing could do this? Enter the heart monitoring t-shirt, an innovation that may redefine personal health management.