An often-overlooked cause of tummy troubles are disordered eating patterns.

These days, many eating disorders are atypical and do not fit the stereotypical athlete “anorexia nervosa” characterized by starvation and refusal to maintain a healthy weight. Often gymnasts are struggling with orthorexia or an obsession with “clean eating” which can lead to inadequate food intake or binge eating disorder which provides very inconsistent amounts of “stool bulk” and can lead to bowel irregularities. Abuse of diuretics or laxatives can also cause bowel issues. Eating disorders can be hard to spot and diagnose at times, but GI symptoms can be a major clue worth exploring with professionals. 

Constipation can occur for a variety of reasons, but restrictive eating patterns and eating disorders can exacerbated slowed gastric emptying and motility.

This slowed motility can then create early satiety (fullness) and cause/exacerbate reflux. When there is inadequate food moving through the digestive system, the gut slows down and becomes “sluggish”. This becomes a vicious cycle where the athlete doesn’t want to eat more as they are “full” or “constipated” and are afraid more food is just going to exacerbate the problem. The counter intuitive solution is more food at regular intervals with a gradual increase in fiber with adequate daily hydration. The gut needs to “wake up” and remember how to process a larger, more normal amount of food. 

For other athletes, “nervous stomach” is a real thing and results in over-stimulation of the sympathetic nervous system.

This phenomenon is usually categorized as “Irritable Bowel Syndrome” or IBS. The stomach and GI tract (small/large intestines) are enervated by the enteric nervous system which is often thought of as the “second brain”. Feelings of anxiousness or nervousness can stimulate the “fight or flight” response in the body and cause nausea and urgent defecation. For these athletes, cognitive behavioral therapy is very effective and should be provided by a trained, licensed therapist.

Another issue that can cause constipation is “stool withholding” or not using the restroom when the urge is there.

This is a major issue in our school age children as they do not want to “go to the bathroom” at school or at the gym. Traveling can also throw off the normal bowel habits and lead to constipation. I counsel my athletes to make sure they are hydrating while traveling (especially since air travel is particularly dehydrating), maintain normal meals/snacks, and leave time to use the restroom in the morning/evening, etc. 

Medical issues like autoimmune GI diseases such as Celiac disease, Crohn’s, and Ulcerative colitis can cause unintended weight loss and nutrient deficiencies, leading to malnutrition, if undiagnosed or left untreated.

Celiac disease is caused by an immune response to the protein found in gluten (commonly found in wheat). Crohn’s and Ulcerative colitis are categorized as “Inflammatory Bowel Diseases” or IBD and effect 1 out of 4 under the age of 20
with the fastest growing age group between 14 and 24. Gymnasts who are diagnosed with these conditions should have regular visits with their pediatric gastroenterologist to monitor treatment, labs, and most importantly growth.
Linear growth or height can take a big hit when an individual is malnourished, especially from malabsorptive diseases like in celiac disease. These athletes should be carefully monitored by a trained registered dietitian who specializes
in pediatric/adolescent gastroenterology. Major micronutrients like calcium, vitamin D, iron, and magnesium can be malabsorbed and lead to low bone mineral density and anemia, thus increasing risk of fracture and injury. Given that
nutritional supplements are not regulated by the FDA and specific amounts need to be given for vitamin/mineral repletion, any supplement should be prescribed and monitored by the medical team. 

For a lot of these conditions, alternative practitioners will throw supplements and probiotics at the athlete which are often ineffective and a waste of money (and unregulated/could be tainted).  

As a pediatric/adolescent registered dietitian nutritionist, my passion lies in helping athletes maintain athletic performance amidst chronic disease. 

As a coach or other health professional, you can watch for the following signs in your athletes and involve parents and the appropriate medical professionals. 

Pallor/Fatigue– Iron deficiency anemia often leads to looking “pale” due to loss of oxygenated hemoglobin. For many athletes, anemia can more commonly present as fatigue and difficulty recovering from training. Athletes with undiagnosed celiac disease or restrictive eating patterns can become anemic which will lead to lethargy, etc. Iron supplements can cause GI distress (upset stomach, constipation) but newer research is supporting a different dosing strategy that leads to less upset. Iron should be prescribed by a physician and monitored through lab work. 

Extensive time in the restroom- We all know that sometimes our athletes like to “go to the bathroom” to avoid hard training sessions, etc. But, don’t just assume this is the issue when really they could be struggling with serious GI issues. Talk to the athlete and parent in private about this issue; it is not something to bring up in front of the entire team or other teammates as GI issues can be really embarrassing and personal to the individual. 

Unexplained weight loss– often times athletes will go through periods where they unintentionally “slim down” due to increased training, rapid growth, and/or inadequate food intake. Not only will this hurt muscular development and adaptations from training but can throw off the hypothalamic-pituitary-axis and cause slowed growth, amenorrhea, and other serious issues. This is where you involve a registered dietitian as they are the licensed qualified professional to provide medical nutrition therapy and assess the athlete’s dietary habits and ensure they are meeting their nutritional needs. I often see individuals that have lost weight which is then not explained by inadequate dietary intake and prompts further workup into malabsorptive conditions like celiac disease or IBD. 

Upset stomach, missed trainings, etc– These issues can be related to anxiety and should be addressed with a sports psychologist or licensed mental health therapist (LPC, LMSW). Your athletes have a lot more going on in their lives these days than we did as kids, and you only see a snapshot of their lives at the gym. Maybe their parents are going through a heated divorce, or they are getting bullied at school for their “muscles”, etc. This is again another situation where you speak with the athlete and parent in private and hopefully have a network in your community of professionals to refer them to. 

I hope you found this GI overview helpful. Please contact me below if you have any questions, concerns, or stories you’d like to share!