Exercise and Menstrual Cramps

How physical activity can ease pain
Author: Sarah Aldridge

Heating pad. Salt and vinegar potato chips. TV remote control. These creature comforts help many women get through that time of the month while they’re curled up on the couch. But there is a better way to ride out the bloating, cramps and nausea that often accompany periods. The answer is just a walk, bike ride or yoga class away.

Cramps 101

Every month, the lining of the uterus, or endometrium, builds up to prepare for pregnancy. If the egg released by the ovaries is not fertilized, this thickened endometrium is shed. “At the time of the period, the arteries clamp down and there’s a sloughing of the tissues that had built up during the second half of the cycle,” says Michelle Warren, MD, professor of medicine and obstetrics & gynecology at Columbia University Department of Medicine in New York City. “Women with bleeding disorders may continue to ooze from those small arteries; therefore, their periods may be very heavy.” Prolonged, heavy periods are called menorrhagia.

As the old lining starts to break down, hormone-like substances called prostaglandins are released. Prostaglandins cause smooth muscles in the uterus to contract, restricting the flow of blood and oxygen to the endometrium, which dies. These muscular contractions, or cramps, squeeze the dead endometrial tissue, the menstrual flow, through the cervix and out through the vagina.

Cramps usually begin a day before the first day of menstruation and peak the next day. They can be felt in several areas—the abdomen, lower back, hips and thighs. Cramps range from mild to severe, with pain that feels dull, sharp, continuous or intermittent. How strong the cramps are may be linked to the amount of prostaglandins and leukotrienes, chemical messengers that cause inflammation and trigger contractions, her body produces. It may also be a function of nerve stimulation. “There are innervations to the uterus that will cause cramping,” says Warren.

For women with dysmenorrhea, or painful periods, it’s important to rule out other conditions. Causes of secondary dysmenorrhea include ovarian cysts, pelvic inflammatory disease, endometriosis and uterine fibroids. (Read “A Difficult Combination,” HemAware: hemaware.org/story/difficult-combination.)

Pain relief the natural way

The feel-good chemical in your brain, called an endorphin, is produced by the pituitary gland and hypothalamus when you exercise. Endorphin, or “endogenous morphine” (morphine produced in the body), is the natural version of morphine, the opiate pain reliever. “It increases the threshold at which you feel pain,” Warren says. Endorphin also improves your mood and gives you a sense of well-being. That’s why marathoners can become mileage junkies, logging in long runs and experiencing the so-called “runner’s high.”

So it makes sense that if you can do something physically to produce more endorphins, it’s bound to take your mind off your body. You don’t have to be an ultra-marathoner, though. Even 30-minute exercise segments can provide a positive effect.

Exercise options

Gentle stretching of the lower back or abdominal muscles might spell relief. “You’re providing a different sensory input to that area, so it might help to alleviate some of the sensation of the cramping,” says Deb Voss, PT, ATC, CSCS, of the Hemophilia Center of Western Pennsylvania in Pittsburgh. “Low back PT exercises include knee-to-chest exercises and lower-trunk rotation.” Progressive muscle release—starting at your head or feet and tensing, then relaxing different muscle groups—might also help with cramps.

Certain yoga poses can help women dealing with painful cramps. A 2011 study in the Journal of Pediatric Adolescent Gynecology showed that pain intensity and duration were significantly lower in approximately 100 adolescent women with primary dysmenorrhea who performed the cat, cobra and fish poses. Plus, there’s the added benefit of mindful meditation and focused breathing. “With yoga, you have the whole mind-body connection,” Voss says. “Helping to relieve stress and strain, and letting go of some physical tension may help.”

Aerobic exercise, in which your body uses oxygen for fuel, elevates your heart rate and breathing. It helps improve blood flow throughout your body and refocuses your thoughts. “Involving yourself in an exercise program can be very helpful,” Warren says. “If exercise were a pill, I’d give it to everybody.”

But with your body feeling like one big throbbing cramp, it’s probably best to refrain from vigorous exercise during your period, say experts. “Women may not feel they’re able to even develop the energy to do high-intensity activity,” says Voss. Instead, some women may prefer light hiking, walking or swimming, she says.

So next time you’re hit by a wave of menstrual cramps, stash the junk food and grab the leash. You and your four-legged friend will both benefit from a brisk walk.