When you increase your physical activity, your body experiences a surge of hormones and your gut motility increases, leading to that sudden "I gotta go" feeling. "It's a dose-dependent relationship," says Terry Wahls, author of The Wahls Protocol Cooking for Life: The Revolutionary Modern Paleo Plan to Treat All Chronic Autoimmune Conditions. "Mild to moderate physical activity levels stimulate gut motility through the autonomic nervous system and changes in the gut hormone secretions in response to exercise."
While extreme increases in physical activity levels can result in digestive issues and even diarrhea, Dr. Vincent Pedre of Pedre Integrative Health believes regular running is a great way to keep your bowel movements consistent. "Leisure running is also going to result in a mechanical stimulation of the internal organs, including your gut, thus stimulating the enteric nervous system, a special network of nerve fibers that controls the contraction of the smooth muscles of the gut lining," he explains. "This promotes peristalsis, which are rhythmic contractions of the bowel. This helps move stool down and will lead to the rectum, where your body gets the signal that your bowels need to empty."
While running once in a while is better than nothing, Dr. Pedre cautions that if you want to rely on running to help you stay regular, you need to run regularly as well and make smart dietary choices.
"Running is reliable for most people, but it has to be done regularly to have a favorable effect," he explains. "And it's not a one-size-fits-all approach because there is not just one cause for constipation. Generally, a person who is incorporating running into their weekly schedule is also being more health-conscious, eating more fiber-rich greens, and hydrating with lots of water, all of which help promote healthy bowel movements."