Best of: The future of exercise

The World Cup is here, and while we watch some of the world's greatest athletes competing on a global stage, it's fascinating to consider what effect this intense activity may have on the human body. With that in mind, we're re-releasing our conversation with Stanford biochemist Jonathan Long on the future of exercise. Jonathan studies the chemistry of what happens inside your body when you move, and his findings are pointing toward some genuinely surprising possibilities — including treatments for obesity, diabetes, and even, someday, an exercise pill. If the athleticism on the pitch has you feeling inspired, this one is...