In the countless hours I have spent in the gym and on the yoga mat, doing crunches and curls to work those important “core” muscles, this has never happened to me. But apparently a fair number of other women are having orgasms while they exercise.

In research published online Tuesday in the journal Sexual and Relationship Therapy, Debby Herbenick, associate director of the Center for Sexual Health Promotion at Indiana University, and her colleague J. Dennis Fortenberry, a professor of pediatrics at Indiana University, set out to document the as-yet-mostly-anecdotal phenomenon of exercise-induced orgasm (EIO) and the related exercise-induced sexual pleasure (EISP).

The notion that women can have an orgasm while exercising has have popped up in scientific and popular literature over the years; Alfred Kinsey made note of it in his 1953 book “Sexual Behavior in the Human Female,” according to the study.

With the aim of simply establishing that EIO and EISP (sexual pleasure from exercise that stops short of orgasm) exist and getting some sense as to who experiences them under what circumstances, the researchers distributed surveys via e-mail to colleagues, list serves, and Web sites related to women’s health, fitness and sexuality; recipients were encouraged to forward the survey to others.

Of the 530 women (ages 18 to 63) who responded, 124 reported having had EIO, and 246 said they’d had EISP.

Those who had experienced EIO had done so an average of more than 10 times. The average age of first occurrence was 18.9 years. Most said their orgasms occurred without their having sexual thoughts or fantasies or having helped things along. Most women (51.4 percent) reported having an orgasm in connection with abdominal exercises; among the other exercises linked to orgasm were weight lifting (26.5 percent), yoga (20 percent), bicycling (15.8), running (13.2 percent) and walking/hiking (9.6 percent). Many women reported feeling embarrassed when they had these orgasms in public and worried that they might “vocalize” during the experience.

Herbenick notes that the popular term “coregasm,” referring to orgasm that occurs when engaging the core muscles of the lower abdomen and back, isn’t quite accurate, as many women’s orgasms occur in the absence of core work, and it’s not clear how engaging those muscles might contribute to orgasm, anyway.

Herbenick readily acknowledges that this was no scientific sampling and that it likely suffered from several biases. The fact that participants were solicited online may explain why so few women older than 50 took part, for instance. And it’s probable that women who had had these experiences were more likely to respond to the survey in the first place than those who hadn’t.

Still, the data provide a foundation for future research into this little-documented, poorly understood aspect of female sexuality and raise all kinds of interesting questions. Does orgasm have meaning and function independent of sex? Could we learn anything from women who have orgasms while exercising that might help women who don’t easily come to orgasm do so more readily?

All in all, the paper highlights how little we really know about female orgasm and how it works. Here’s the authors’ conclusion:

“Every day, around the world, millions of women experience many millions of orgasms in dreams, from their erotic imaginations, from masturbation, from partnered sexual behaviors and, perhaps, from specific exercises. The quotidian nature of orgasm reminds us to be especially cautious in claiming new insight that ‘rewrites’ our understanding of the phenomenon: the study of women’s orgasm is marked by a ghastly trail of mostly misogynist science and pathologizing but nearly inept medicine. However, we believe our data challenge existing approaches to orgasm as the outcome of an inherently sexual production and that findings from this study may provide insights or opportunities for women to better understand their experiences with exercise as well as orgasm.”