Working hard to improve a skill or ability, such as learning how to drive or solving a math problem, may increase stress in the short-term, but makes people feel happy and more content with their lives in the long run, a 2009 study reported.

"People often give up their goals because they are stressful, but we found that there is benefit at the end of the day from learning to do something well. And what's striking is that you don't have to reach your goal to see the benefits to your happiness and well-being," co-author Ryan Howell said in a statement.