That is, unless you employ these seven incendiary strategies to keep the sparks flying

By Matt Bean and Denny Watkins

Boosting her dopamine levels outside the bedroom could pay dividends between the sheets.

“Your brain can’t differentiate between the external anxiety caused by a novel situation and the internal anxiety caused by being attracted to someone,” says Dr Victoria Zdrok, a clinical psychologist (and former Playboy Playmate – hello!) “A boost outside the bedroom can carry over for when it matters most.”

The best way to increase her anxiety, sans cardiac arrest? Competition, reveals Zdrok, which helps release sex-drive-boosting testosterone. Why not enter as a duo in a triathlon or sign up for a pub-trivia night?

By competing on the same team, you’ll also improve communication and cooperation, the two behavioural foundations of sexual success.

Revisiting that bed-and-breakfast romp of three months ago isn’t just an exercise in nostalgia. Recalling the relationship’s formative moments can stir up the hormone norepinephrine, which helps the brain shine an emotional arc light on memories.

“You’ll unlock her passion,” advises sex therapist Dr Laura Berman, Director of the Berman Centre in Chicago, “and also intensify the new memories you’re making.”

The brain’s internal archivist responds best to strong contextual cues – smells, environments, music, textures, even certain foods – so orient her mental rear-view mirror
by concocting a smorgasbord of evocative sights and sounds.

The monogamous North American prairie field mouse might not be your sexual role model, but researchers found that the creatures are literally addicted to their mates, thanks to their receptivity to oxytocin.

That hormone battles stress and increases arousal (it’s released during orgasm, after all), so the lesson here is clear: up her dosage and she’ll be hooked on you.

Physical contact (cuddling) and muscle massage both unleash the chemical, so give her this sensual massage in the post-coital glow: ask her to lie face-down and, straddling the backs of her upper thighs, apply rotating thumb pressure to either side of her lower spine, advises Dr Linda Banner, author of Advanced Sexual Techniques.

By the time you reach her shoulders and neck, the oxytocin jets should be firing full force.

It pays to be her sexual party doll every now and then. A study at the University of Michigan in the US found that female rats receive a dopamine boost (the euphoria-inducing neurotransmitter) only when they control sex. But don’t just offer her the blow-up valve.

“Make sure she’s not just hearing ‘Do me the way I want to be done’,” says sex therapist Dr Gloria Brame, author of Come Hither.

Instead, she suggests you try a bit of role-playing (76 per cent of women surveyed by Men’s Health said they’d be game for a little play-acting) in which she’s in a position of authority and you’re the sexual novice. The fantasies women said they liked most: professor/student and nurse/patient.

Reinvent yourself outside the bedroom and you could help refresh her passion inside it.

Researchers at the Massachusetts Institute of Technology in the US claim we keep a sort of neural dossier on a person tucked away in our brain, just above the temples.

This case file is overhauled when we meet their friends or develop deeper /mens-health/sex-relationships/couples/relationships with those we’ve already met, advises Dr William Pollack, a professor of psychiatry at Harvard Medical School and a Men’s Health mental-health adviser.

“She’ll see you through their eyes, and it will bring out different aspects of your own personality,” adds Pollack, “stimulating love and lust neuro-transmitters.” So introduce her to Jack and Meg from your cycling group at a dinner party: it could encourage her to attack your body anew.

Trying new sex positions isn’t just a new way to fit the key into the lock.

“Anything novel or exciting is likely to drive up the levels of dopamine in her brain,” according to anthropologist Dr Helen Fisher, author of Why We Love.

Magnetic-resonance-imaging scans done at Oxford University found that learning a new motor skill – whether it’s fingering bar chords on your guitar or plucking a new sexual harmony in bed – sets off a flurry of activity in many of the same brain regions activated during orgasm.

Send your sex life back to square one. “If you’ve learnt how to pleasure her, it’s too easy to forget about foreplay and all the other things that keep sex fresh,” warns Dr Debbie Herbenick.

Start with a three-day sex break to build anticipation, pooling dopamine behind her sexual Warragamba Dam. Then spend a night pashing like teenagers, clothes on. Wait two days and spend another one touching each other sensually – everywhere but the genitals. Take two more days off and then use your lips instead of your fingertips to do the same.

By this stage, your dopamine will be red-lining and both of you will have a surplus of arousal-boosting testosterone. Bonus: the heightened physical sensitivity can unearth long-neglected erogenous zones when – finally – at the two-week mark, you blow the dam.

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