That persistent idea that you need to walk 10,000 steps a day to stay healthy? It didn't come from rigorous medical research—it came from a clever 1960s marketing campaign for a pedometer.

Jack McNamara, senior lecturer in clinical exercise physiology at the University of East London, explains that the round number was simply easy to remember and catchy enough to stick around for decades. The good news: this debunking opens the door to a more personalized approach to fitness, where your ideal step count depends on your individual circumstances and goals rather than chasing an arbitrary target. Read the full story →

Today's takeaway: You don't need a magic number to be active—focus on movement that works for your life, not Madison Avenue's.