Dropping your daily activity level for as little as two weeks can raise your risk for diabetes, heart disease, and premature death, a new study suggests. Researchers found that when men cut their activity level--by taking an elevator instead of stairs, or by driving to do errands--their insulin levels spiked dramatically. And these metabolic changes occurred even if the men did not gain weight. But researchers say that on the positive side, it's possible to improve insulin levels within a few...