Romance novels, porn, role play, lingerie. They’re all great ways to turn on your sexual accelerator, but usually aren’t enough, according to Emily Nagoski, PhD, a sex educator and author of the best-selling book “Come as You Are: The Surprising New Science That Will Transform Your Sex Life”.

“Those things are great if you like them, go ahead, but it turns out that people are struggling usually not because there’s not enough stimulation to the accelerator — it’s that there is too much stimulation to the brake,” Nagoski tells NBC News BETTER.

Nothing triggers your brake more than stress, according to Nagoski.

“Stress is a survival mechanism to help you when your body is sending you signals that say you are not safe right now,” Nagoski says, “and if you’re not safe right now, is that a good moment to be having sex?”

No matter how much you’re trying to pump the accelerator, chronic stress can completely squelch your sex drive, says Nagoski. Work, childcare, and reduced sleep are just a few things that can step on the brake, she says.

For many long-term couples, the pressure to maintain a consistent sex life is a great source of stress, says the author, and, ironically, is often the reason they’re not having it consistently.

Here are some techniques couples can use to get their accelerator going, according to Nagoski.

Schedule time for sex

Couples who stay in long-term, happy relationships usually prioritize sex and even put it on their calendars, says Nagoski.

“Some people hear that and think, ‘Well that’s not really romantic, how much can your partner want you if they have to schedule it?’” she says. “But is there anything we do in our lives that’s important to us that we don’t schedule?”

Nagoski says scheduling sex gives you time to eliminate any stressors that are hitting your brake, whether it’s work-related stress or making sure the house is clean.

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“There is preparation time where you can do whatever it takes for you to reduce your stress levels or get your accelerator warmed up,” she says.

Avoid the ‘chasing dynamic’

You want sex. Your partner doesn’t. Or so it seems. Often, when one partner wants sex, it isn’t about a desire for pleasure — it’s about a need for intimacy, she says.

“They want the connection, they want the acceptance, they want to feel wanted by their partner, and it can feel scary when your partner continues to say ‘no.’ What are they saying no to? Are they just saying no to the sex or are they saying no to all of me?”

If your partner doesn’t seem interested, don’t assume it’s because they aren’t attracted to you, says Nagoski. Chances are, they’re just overwhelmed.

“It absolutely is not the case that a partner is saying no because they’re not attracted,” she explains. “Usually, it begins in a place of ‘I’m just stressed out and exhausted and I’m not interested right now,’ and then it turns into what I call ‘the chasing dynamic.’”

If your relationship lacks sex, the worst thing you can do is chase your partner, Nagoski explains. Chasing them will increase their stress and slam on their brake, she says.

Stop focusing on sex

If you want to accelerate your sex life, you need to stop making sex the goal, Nagoski says. Instead, she says to focus on building intimacy.

Agree that you and your partner will go for a certain period of time without having sex, she says. Once the pressure is off, you’ll have space to be more intimate in other ways.

While you’re on your sex break, make time each day for cuddling and kissing (Nagoski recommends the six-second kiss by relationship therapist John Gottman). Hugging and kissing may seem trivial, she says, but they are a great way to build intimacy. What’s more, they will reduce stress levels and get you both in the mood to have sex, she says.

“It reinforces the bond and the idea that you are safe and affectionate with this person,” she says. “It also creates physical affection in the relationship that is not initiation.”

See a sex therapist

Couples who have a strong friendship should be able to do these exercises to rebuild intimacy, says Nagoski. If you and your partner find it difficult, Nagoski recommends seeing a therapist who can help.

“My first recommendation is always to find a sex therapist,” Nagoski says, “because we are all so tender and sensitive around sexuality, and it can be difficult to talk with each other about it in a way that is never blaming and never hurtful.”

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