When women are experiencing primary dysmenorrhea (better known as period pain), usually the last thing that they feel like doing is getting up and exercising. According to a new first-of-its-kind study, however, doing so may be exactly what's needed to reduce the discomfort.

An international team of scientists began with 70 female test subjects, aged 18 to 43. Starting the day after the end of their menstrual period, half of the women began a supervised aerobic exercise regime, which involved using a treadmill three times a week for four weeks. They then continued with that regime unsupervised in their homes, for an additional six months.

The other half of the test subjects performed no exercise over that same period, serving as a control group.

After the initial four weeks, the exercise group reported a 6-percent reduction in menstrual pain, as compared to the control. That figure increased to 22 percent after the six months of unsupervised treadmill use. Additionally, once the seven-month exercise period was over, significant increases in quality of life and daily functioning were reported.

Notably, however, there was no improvement in sleep quality. Nonetheless, the study appears to generally back up the long-standing notion that exercise helps to lessen period pain.

"Women who have painful periods often take steps to actively avoid exercise," says team member Dr. Leica Claydon-Mueller, of Britain's Anglia Ruskin University. "However, this trial demonstrated that exercise significantly reduced pain for those people taking part in the program."

A paper on the research – which also involved scientists from Hong Kong Polytechnic University and New Zealand's University of Otago – was recently published in the journal Contemporary Clinical Trials.