What Does It Mean When Your Stomach Is Cold When You Work Out?

Stomach issues can turn your workout routine or morning run into an uncomfortable experience. Almost everyone has felt that cold, clammy feeling on their stomach during an intense cardio workout. Despite the discomfort, the feeling of a cold stomach doesn't have to end your routine. Understanding the cause and the associated issues of a cold midsection can improve the quality of your next training session.

Your gastrointestinal system is primarily made up of the stomach, small intestine and large intestine, along with a complex group of muscles and lesser organs. According to nutrition and epidemiology researcher Christopher D. Jensen, Ph.D., MPH, RD, 52 percent of runners reported symptoms of gastrointestinal distress during a marathon, and 71 percent of the gastrointestinal issues occurred in the lower gastrointestinal tract. Symptoms vary across activities, but are a very common occurrence for endurance athletes.

A cold or clammy stomach is one of the most common symptoms associated with exercise, and occurs when the cardiovascular system pulls blood to the legs. Jessica Girdwain writing for "Fitness" reports that an intense workout like a long-distance run can shift up to 80 percent of blood flow to the leg muscles, primarily in the quadriceps. This blood is pulled away from organs, like those of the digestive system, that have a reduced energy need during the workout.

The reduced blood flow to the gastrointestinal system can leave you with a cold feeling in your stomach. During a workout, this diverted blood flow means your stomach is the last part of your body to warm up. Your legs, particularly the quadricep muscle group, will heat up much faster, leaving the stomach comparatively cool. This feeling is normal and indicates your body is correctly compensating for the greater energy needs of your most important muscle groups.

A cold stomach may not be a threat to your workout, but less blood flow to your digestive system can cause gastrointestinal issues like nausea, indigestion, and diarrhea. These symptoms can be prevented by waiting two to three hours after eating before beginning a workout. Good hydration prevents many gastrointestinal issues, and an easy warmup before a grueling workout can address a lot of issues before you're well into your workout.