Injure means to hurt, physically or mentally. Lose a bet and you might injure or bruise your pride, but lose your footing and you could injure your body instead.
When a player in a sport is injured, they leave the field to be examined by a trainer or a physician, to see how severe their injury really is. If you slip and fall on the ice, your mom might say, "Are you injured?" She doesn't mean a bruise–––she's talking about a broken bone or a sprained ankle. You can also injure or wound someone else. Insult your mother's cooking or tackle your little brother too roughly to the ground and you'll injure them, either emotionally or physically.