Who hasn’t plunked down a pretty penny to join a health club or invest in pricey running shoes with the intention of starting a fitness routine “for real this time” — only to let the gym membership languish or the shoes morph into chew toys for the dog?

About half of all folks who try to commit to regular exercise, that's who. Research shows that 50 percent of people who start a fitness routine drop out within six months. Some quit because they’re self-conscious, others because they aren’t getting the results they want. But for some the reason their shape-up plans don't take shape is they just can’t get into the habit.

If you feel like the only thing standing between you and the health and feel-good benefits of regular exercise is an inability to get into a groove, new research may hold the key. The study, published in the journal Health Psychology, looked at “whether a habit of instigating exercise might be more related to exercise frequency than a habit of executing exercise,” says author Alison Phillips, PhD, assistant professor of psychology at Iowa State University.

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Creating one habit so you stick to another

Phillips' research found that creating what are called instigation habits is highly effective at helping people hit the gym or head to yoga class. An instigation habit is one that prompts you to perform another behavior automatically. For example, turning on the coffee machine each morning may remind you to take your vitamins.

Let’s say you want to exercise after work each day. You might create a series of behaviors that you do every evening that leads you to the gym. First you clear off your desk (pencils in drawer, papers filed, computer off), refill your water bottle and grab your workout bag and head to the gym.

Or perhaps you're an early bird — you know the best time to work out is the morning, but despite your best intentions you dawdle in the a.m. until it's too late to go for a run. Put your running shoes by your bed instead of slippers and get into the habit of lacing them on first thing in the morning. Then come up with a couple more things to do each day before you run (brush your teeth, feed the cat). 

You’ll have to follow your instigation routine deliberately at first, of course. Phillips says that typically it takes about a month for a habit to catch hold. And while it would be ideal to do it every day, three days a week should do the trick if you keep it up.

“As long as the context in which a person exercises is consistent, it should develop into a strong habit,” Phillips says. 

Related: Why You Should Take Your Exercise Routine Outside

A cure-all for all exercise dropouts?

Phillips points out that for some people, having a specific routine can be comforting and build confidence, but others might find this approach boring. 

If you want to try it, though, make your instigating routine as enjoyable as possible. Maybe you'll want to add listening to upbeat music in the car as you drive to the gym after work, for instance. “The more intrinsically motivating a behavior, the stronger the habit-instigating cues become,” Phillips says. 

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Amy Roberts is a certified personal trainer. She writes about fitness, health and a variety of other topics for many well-known publications.