A: holding grudges

How Holding Grudges Makes You Physically Weaker Forgiveness scores you more than good karma points: People who let go of personal grudges see the world as less daunting and perform better physically than those who hang on to their resentment, finds new research from the Netherlands.  In the study, participants who remembered a time when they refused to forgive someone judged hills to be about 5 degrees steeper than those who recalled making amends.  Forgivers also jumped an average of 3 inches higher in a fitness test than their still-bitter counterparts, suggesting that ill will can literally bring you down.  “Victims of conflict often suffer from a feeling of powerlessness—a sense that they are unable to control their own situations,” says study coauthor Ryan Fehr, Ph.D. And that resulting perception of mental weakness can actually drain your body’s physical resources, making tasks like climbing up a hill or jumping more difficult, he says.   Plus, when you hold a grudge, you tend to stew over it. This can deplete the availability of certain cognitive-boosting resources in your body—like blood sugar—that help you cope with physical challenges.