American College of Cardiology Apr 22 2026 How fit you are in midlife may help determine not just how long you live, but how many of those years are spent in good health, according to a new study published today in the JACC, the flagship journal of the American College of Cardiology. The study found that adults with higher levels of cardiorespiratory fitness in midlife lived longer lives, developed fewer chronic diseases and spent more years free from serious illness compared with those who