To prevent performance anxiety from interfering with a healthy sex life, mindfulness is an answer

Ian Kerner is a licensed marriage and family therapist, writer and contributor on the topic of relationships for CNN. His most recent book is a guide for couples, "So Tell Me About the Last Time You Had Sex."

(CNN)Just as in a summer blockbuster, there are superheroes and supervillains of sex. The most powerful hero is arousal — the warmth we generate when we touch, the fantasy that turns us on. It's the mechanism by which we climb the peaks of pleasure. But like a classic movie standoff, arousal often never gets a chance to shine, thanks to its nemesis: anxiety.

"Anxiety hits the soft spot of vulnerability, making it hard to be present and aroused," explained California-based sex therapist Jean Pappalardo. "Anxiety about sex and intimacy may start as a 'yield' sign and eventually become a 'stop' sign. It can be paralyzing."
By anxiety, therapists mean feelings of fear, nervousness, and worry that can interfere with daily life.
    There are any number of reasons why you might feel anxious about or during sex, but at their core, they usually involve "spectatoring" — a sense of being more concerned about the performance of sex than the actual act of it. Spectatoring prevents us from being in the moment and letting go.
      In my experience, people spectate around all sorts of concerns: Will I function the way I feel I should? Am I a good lover? Is this pleasurable for my partner? Am I meeting my partner's expectations? How does my body look? How do I compare? Am I going to be expected to do something I'm uncomfortable with because I know my partner wants it?
      These concerns can often be traced back to something in our sexual history. One woman I worked with had been told that she wasn't a good kisser. One of my male patients was mocked for being uncircumcised. Such triggering events initially led to anxiety, which in turn impaired sexual function. Now, the anxiety itself triggers performance issues for these patients, often creating a vicious circle.
      Other people may find that heightened anxiety outside the bedroom — whether the result of an anxiety disorder or life's general stresses — can impede what goes on inside the bedroom.
        "People who struggle with anxiety often have a hard time relaxing, so their ability to tune into their sexual sensations and allow arousal to happen is compromised," said Deborah Fox, a sex therapist in Washington, DC. "They put so much energy into managing their anxiety that takes them away from enjoying themselves — including the spiciness of sex."

        How anxiety manifests in your body

        Anyone who has experienced anxiety is likely familiar with its most obvious symptoms: Your heart races, you breathe more heavily, you experience "butterflies in the stomach," which often show up as digestive woes. Chronic anxiety can be more insidious, making itself known in the form of irritability, depression and low libido. It can affect sexual arousal and function in other ways, too.
        "For people with penises, anxiety can affect blood flow leading to the inability to achieve or maintain an erection," said sex therapist Kristen Lilla, who practices in Nebraska, Iowa and Wisconsin. "For people with vaginas, anxiety can cause you to tense, tig