When it comes to exercise for heart health, you don't want to peak too early in life. Recent research suggests that if you want to protect yourself against high blood pressure as you age, you need to play the long game and keep your exercise levels up through middle age. But social factors can make this more difficult for some people to do than others, according to a study of more than 5,000 people across 4 US cities. "Teenagers and those in their early 20s may be physically active but these patterns change with age," study author and epidemiologist Kirsten...