Feeling unproductive at work? Generate genius off the clock. Doing creative things outside the office can boost your job performance, finds a new study from San Francisco State University.

The reason: "Creative activities may provide employees a greater confidence to succeed and a sense of self-worth," says study author Kevin Eschleman, Ph.D. “These resources, in turn, can transfer over to the job." The key is to make sure what you're doing is intrinsically rewarding and lends itself to discovery and self-learning, says Eschleman.

In the market for a new hobby? Try these three brainpower-boosting activities:

Cooking: Experimenting with recipes and improvising in the kitchen can spark the creative process, a study in the Journal of Consumer Culture suggests.

Cycling: Dutch researchers found riding your bike could help hone your problem-solving skills.

Hiking: In a study at the University of Utah, participants who spent 4 days trekking in nature without electronic devices scored 50 percent higher on a creativity test than those who took the test before unplugging and heading into the woods.