Doctors and health professionals often recommend exercise as a cure for constipation. However, your digestive system is very complex and it's hard to change one part of the system without affecting something else. Although there is no scientific research proving that exercise causes constipation, it is theoretically possible that increasing your exercise without drinking and eating more could slow down your bowels.
Constipation happens when food stays in the intestine too long, and the digestive system has a chance to pull too much water out of the waste products. This results in a hard, dry stool that can be difficult to pass. There is no set number of stools per day or per week that is considered "normal," according to the Mayo Clinic. But many people complaining of constipation have fewer than three stools a week, and those few are hard and dry.
There are some serious health problems that cause constipation, but the most common causes are a low-fiber diet, a lack of physical activity, not drinking enough water and putting off going to the bathroom when you feel the urge, according to Medline Plus.
When you exercise, your body sweats to keep you cool. This produces an increased demand for water in your body, and your intestines may recoup the water loss from your stools. If you have noticed that increasing your exercise routine seems to increase your constipation, be vigilant about the amount of water you are drinking. Make sure you drink before, during and after your workout. Avoid sugary drinks and diuretics like caffeine.
The American Society of Colon and Rectal Surgeons says that the average American diet includes 12 to 15 grams of fiber per day, but 25 to 30 grams of fiber would be better for digestive function. The organization also recommends drinking about 60 to 80 ounces of fluid each day, which is about eight to 10 glasses.
If you recently increased the amount of exercise you do and notice that you're having a hard time passing a bowel movement, look at other factors in your life that may have changed at the same time. If you started a new diet at the same time you began exercising, it is possible that you aren't consuming enough fiber — especially if your diet limits fruits, grains and vegetables.
If your constipation is so severe that it's disrupting your normal schedule, see your doctor to rule out serious health issues. Don't quit your exercise program unless your doctor tells you to. Drink more water and look for healthy high-fiber foods like whole-grain breads, beans, and fresh fruits and veggies to round out your diet.