The Science Behind Nailing Your New Year's Resolution

— -- New Year's resolutions seem so exciting and full of promise on Jan. 1, but by the middle of the week, many people have already skipped gym, eaten the stacked burger and been a jerk to their in-laws.

No one said goal-setting would be easy.

Fewer than one in 5 adults who made health-related New Year's resolutions were able to make any significant strides in weight loss, healthier eating, exercise or stress reduction by March, according to a 2010 poll by the American Psychological Association.

Still, psychologists say there's no time like the present to give your goals a try. And if you want to be a better version of yourself in 2015, there's a science to conquering your resolutions.

Read on to find out how to stack the deck in your favor and do your New Year's resolutions right this year.

Choose Your Goal Wisely

The key to accomplishing your goal is to make it concrete and easy to break down into pieces, said Jeff Janata, chief of psychology at UH Case Medical Center in Cleveland, Ohio. Weight loss is actually an example of a resolution that sets you up to fail.

"Weight loss really isn't in our control," Janata said, explaining that no matter how rigid the diet and exercise, weight loss naturally plateaus. "That's one of the reasons people fail at weight loss. They focus on 'I need to lose a certain number pounds per week.'"

Instead, cutting out fried foods or deciding to work out a few days a week are better goals, he said.

"Don't start off with these grand resolutions," said psychologist Joe Taravella, the supervisor of pediatric psychology at NYU Langone's Rusk Rehabilitation who also specializes in marital and family psychology.

Don't Beat Yourself Up If You Mess Up

No matter how perfect the goal is, Janata said people are going to slip. But that doesn't mean they should give up completely.

"Re-adjust the goal according to how difficult it is for you," Janata said.

He advised taking 2015 goals week by week or day by day.

"I remind people that we're human and we're not perfect," Taravella said. "We're going to mess up throughout our entire lives."

He said one bad day "doesn't mean we're total failures and all progress we made isn't meaningful."

Reward Yourself

Building in days off is an important part of goal-setting, Taravella said.

"Being totally rigid 24/7 is not sustainable over the long haul," Taravella said.

Go Public

Want to make sure you nail your 2015 resolutions? Make them public, psychologists advised.

"Talk to people about what you're doing, so you can be accountable," Taravella said, explaining that you'll be motivated to succeed because you won't want to fail in front of your friends.

Make Sure You're Doing It for the Right Reasons

Tackling a goal because someone told you to or because you simply think you "should" might backfire, Janata said. Sometimes, taking on a goal because of outside pressure just makes people want to rebel, he said.

"There's an important distinction to be drawn between goals that we feel that we should accomplish and those we believe we truly want to accomplish," he said. "Rarely do we attain goals unless we truly embrace the goal."

So make sure you're only picking goals because you're ready and eager to fulfill them.