Is there science behind keeping the spark alive in long-term relationships? A psychology researcher from the University of British Columbia says yes ... and she's got tips on how to keep love alive once the initial lust and sparkle dust starts to fade.

First, UBC's Heather Morton gives some background on her research:

Many non-human animal studies suggest that novelty may plan an important role in sexual functioning. This has been frequently demonstrated by the Coolidge effect, where a male will copulate with a female repetitively until he's satiated and is no longer interested in continuing. But when a new female is introduced, he's interested again. Although you clearly can't do this with humans, there are some areas of research that have examined this phenomenon indirectly.

Her work provided evidence in support of what's hardly a new theory: in long-term relationships, "sexual satisfaction, and sexual desire decline over time with the same partner," and that this happens to both men and women.

So, what can folks in committed relationships do? Turn to common sense ... backed up by science.

"What we're now in the process of studying is whether couples can reverse the effect of declining desire by increasing novelty within their relationship, such as engaging in a greater variety of leisure activities together or in a wider sexual repertoire," Morton says. "It can also be helpful to understand that this is natural — that there's not something wrong with you or your partner."

In addition:

Couples may be able to gain the benefits in sexual functioning that accompany a new partner by introducing novelty in other ways. Previous studies have shown that engaging in exciting activities together increases relationship satisfaction, however the impact on sexual functioning was not examined. Early results from one of our studies suggest that men and women who engage in a greater variety of sexual activities experience greater sexual desire and satisfaction. It appears as though the frequently given advice on 'spicing up your relationship' may in fact be spot on.

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