Coming Back from a Stomach Bug: Gastroenteritis Treatment for Athletes

No one likes a stomach bug, least of all an athlete motivated to train or getting ready for an upcoming event. Whether it is from a bad plate of food (bacteria) or something your kids brought home from school (virus), you have most likely had minor gastroenteritis and the end result will be a physically draining but relatively short-lived experience that encompasses vomiting, diarrhea, or sometimes both.

As coaches, we get plenty of panicky calls from athletes who come down with gastroenteritis. Sometimes it’s during training, especially when kids go back to school or in the winter when people are so close together indoors. During the competitive season, we get a lot of call in the week leading up to a goal event. This is often the time when athletes get sick because they are either traveling to an event and eating/drinking in areas they’re not accustomed to, because they are nervous/stressed due to their events, or because their immune systems are a bit compromised.

Gastroenteritis vs. more serious illnesses

The first thing you need to do is try to differentiate between a minor gastroenteritis and more serious illness. Nausea, vomiting, and diarrhea come with the territory and may be accompanied by a low-grade fever. But a high fever (above 101 degrees F) should be a warning sign of a more serious illness. Similarly, vomiting lasting more than 48 hours, or leading to significant dehydration, is serious and you need to seek medical attention. Honestly, if it’s the week before a big competition seeing a physician is a good choice if you can.

Most of the time athletes get hit by minor gastroenteritis, the type that comes on quickly, makes you feel terrible for 1-2 days, and then goes away. From a performance standpoint, the impact can be huge. You’ll go 24-48 hours with little nourishment, you’ll lose significant amounts of fluid and electrolytes, and you’ll burn through energy stores you would rather save for race day.

Return to exercise or competition after gastroenteritis 

So, if you get nailed by gastroenteritis, is there any hope you can still have a good performance in the next few days? The answer is yes, as long as you treat the illness like an endurance event.

  1. Understand the goal:

    Gastroenteritis drains you of fluids, electrolytes, and energy. As an athlete who wants to get back to training or compete within a week, your goal is to minimize these losses. One mistake athletes make is to just curl up in a ball and wait for the illness to pass. If you’re not taking anything in to balance the depletion, the fluid, electrolyte, and energy deficits grow and grow. Your goal is to keep those deficits as small as possible, so you have a better chance of closing the gap once you feel better.

  2. Prioritize:

    Fluids are most important, followed by electrolytes, then calories. Not only are the consequences of dehydration and electrolyte imbalances more detrimental to health and performance than a lack of calories, they take longer to recover from. Your body is very good at packing glycogen into muscle cells and restocking liver glycogen. It takes longer to fully replenish fluid levels in tissues.

  3. Eat like an athlete:

    When you’re in a long training session or competition, you primarily consume fluids, electrolytes, and small portions of simple foods. When you’re suffering from gastroenteritis, you pretty much want to do the same thing, and you can even use some of the same foods. Water is an obvious choice, but simple sports drinks (essentially carbohydrate, electrolytes, and water) may be a good choice as well, if you can tolerate them. Salty foods can also be good, just keep your choices bland and simple (like crackers) when you’re nauseous. Most important, you should be consuming something regularly and frequently, just like during an endurance event.

Post-illness replenishment

When you finally feel human again, the worst is over but there’s still work to do. Now you must replenish what you lost. Your gut is still irritated so don’t overwhelm it with complex foods. Continue eating simple ingredients in small portions on a frequent basis. Ideally, if you have about 3 days between the end of a 24- to 36-hour bout of gastroenteritis and your event, you can have a strong performance. More time is even better. However, if you have less time, be prepared for a slow day and understand you may reach a point where dropping out is the right choice.

You could also have a surprisingly great performance. Moderate and temporary weight loss is often a consequence of gastroenteritis, and even though most of that weight loss is from dehydration, some athletes are still able to experience weight-related improvements in performance.

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On the other hand, it’s not uncommon for athletes to start out feeling great, and then suffer a rapid decline. This is most likely due to fuel depletion, and it seems to happen more frequently for athletes in high-intensity events like 5k/10km running races, cycling criteriums, sprint triathlons, and cyclocross. Athletes who compete at moderate intensities for longer periods may be able to avoid this sudden feeling of emptiness by consuming calories early during events.

Gastroenteritis sucks, but like most things in life and sport, the worst thing you can do is throw up your hands and give up. Stay focused, work the problem, and be patient. Don’t give up; it’s not pleasant but there have been plenty of champions who have gone from puking to the podium in less than a week.

By Jim Rutberg,
CTS Pro Coach & Co-author “The Time-Crunched Cyclist” and “Training Essentials for Ultrarunning”

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Comments 26

  1. Pingback: Surviving Gastroenteritis: Tips for Athletes – The Family Doc Blog

  2. I am not a competitive athlete. I am a so-called avid cyclist. A lot of advice assumes diarrhea and vomiting are relatively benign. They can also mask horrible diseases like IBS, ulcerative colitis, or worse. After a week, get checked out by a doctor. Being fit does not make you immune from serious illness.

  3. This is some really good information about gastroenterologist treatment for athletes. My little brother is a huge runner and lately, he has been having some stomach issues. It is good to know that he should try consuming more fluids and electrolytes.

  4. I’m not a full-blown athlete but I do try and stay active as best as I can. Now I do like how you mentioned that if I did happen to get a stomach bug, that it would be best to prioritize fluids. I wouldn’t want to get sick from getting sick as it’s important to stay hydrated with fluids and then with electrolytes. If it got worse, then I would see about going to a doctor as they would have a good course of action to follow for me to get better.

  5. Pingback: Really Bad Gastroenteritis | The Best Gas

  6. i had an upset stomach for a day and but it’s now been 24 hours since I have last vomited. I feel fine and I can eat normal nutrition. Could i go to my usual 2and 1/2 hour gymnastics session this evening

    1. I am going through that right now. It’s been off and on for a week. Advice: stay really hydrated, eat really bland comfort foods, and see a doc if it doesn’t go away in 7-14 days on its own. You could have salmonella or, worse, an e-coli infection. Unfortunately neither are easily treated, but your doctor would know what next steps to take.

  7. Been down with what I think is norovirus. It hit me late Sunday night (soon six days ago) and was quite rough as I had 7 rounds of vomitting, each every hour or so, and also got a pretty high fever the following day (monday that was). Fever was 38.7-38.9 highest). On tuesday I still felt rather weak and with a head ache, fever down to just around 38 and a bit below, but had trouble taking in food (no apetite, and felt still a bit unwell in the stomach). Had a last round of vomitting tuesday night after trying pizza (not a good idea obviously). On Wednesday I was still not really back on my feet, though in better shape than the day before. But this day a really bad head ache and also general feeling of being rather fatigued. Gradually startet eating more from Wednesday. But had still a bit troubled stomach. Last two days I was back at work, feeling better but not great (still a bit more like 80 % energy level). But these days I managed to eat more normally and drink more also. Still I havent been much to the toilet yet after the illness, and the stomach still not perfectly at ease.
    SO – the thing is that tomorrow, Saturday, there is a 10 K race I would like to participate. I tested a run tonight and it felt “ok”, not more, not less. I ran pretty easy, so didn`t really test the limits and push it. My plan is to see how I feel tomorrow and go for it if the feeling is ok. However, I wonder if this is risky to do so quickly after the illness? After all, I had two days of vomitting (but still most on the first, just one episode on the second) and three days out of work, and initially a really high fever. Still, my hope is that this is a kind of virus where you can actually be back in action rather quick and dont have to build up slow afterwards? Haven`t been able to find much advice on the topic. I understand that you probably will not be able to answer before my race (16.00 tomorrow, saturday 29th), but anyway it will be of great interest to hear your thoughts on this one.

    All the best,

    Anders from Norway

    1. Hi Anders, thanks for the post am pretty much exactly in the same position, reckon I will do the race but will treat it as a training run as I paid for it, no way I’ll be going full on feeling like this.. Might do the first 7k slow and gun the last 3 if feeling up for it..

  8. I have had gastroenteritis meaning I have been vomiting and having an upset stomach the last 2 days, I have a volleyball tournament in 2 hours and I still have an upset stomach and feel ill, should i take part in the event or give it a miss?

    1. Post

      Sorry we didn’t see your post until well past the event. If we had, we would have recommended that you give it a miss. Two days of vomiting and/or diarrhea will leave a person significantly dehydrated. You probably haven’t eaten much – or anything – in the past 48 hours, either. None of that adds up to a successful volleyball tournament. That said, if you felt up to it, perhaps you went to support the team, or suited up and gave it a try. – Jim Rutberg, CTS Pro Coach

      1. Norovirus is a very common winter cause of gastroenteritis. It is highly contagious for days to weeks after resolving in an individual. By telling someone in a highly social interactive sport to ‘give it a try’ you will likely sicken other people. Individual sports less likely, team and ball sports…not a great idea.

        1. Post

          Thank you for pointing out the risk of transmission. I’m sorry I overlooked that in the above response and the article as well. We’re going to add a section about the risk of transmission. – Jim Rutberg

  9. Thankyou for the article, it makes sense and I wish I’d read it earlier! I am a novice Triathlete and have a sprint Triathlon tomorrow morning. I’ve had diarrhoea since Thursday though not constant. Last proper food was Wednesday evening. So far I’ve eaten dry biscuits and toast. I’ve drunk plenty but only water and black tea. Should I still compete or pull out? What should I eat today if aiming to compete still?

  10. Thanks for the article. Currently I’m that guy curled up in bed, only to get up to vomit and then snacking on plain bread or an apple, neither of which stays in long.

    I would love to compete in my half marathon this Sunday, but right now I can’t imagine I will.

    1. William I’m certainly no expert but I would think the Apple may be too fibrous and may not be helping? Try clear liquids, bland foods and possibly electrolytes in form of sports drinks? Hope you feel better soon

      1. If you have diarrhoea, apple will help to bind it up actually.

        For either diarrhoea or vomiting, a banana is a good choice though. Plenty of excellent fuel choices for the body, and if it does come back up, let’s just say there are worse things. (I had whooping cough a few years back and ended up with over 100 days of vomiting, so I’d like to think I’ve acquired some authority on the subject by now unfortunately).

  11. Pingback: Running After Stomach Illness

  12. Good article. Most of the ‘average’ (using USATF recent numbers) athletes would probably just throw in the towel but for the people who spend so much time training that’s when you have the big choice to make.

    I ended up running a 1/2 marathon today mid-gastroenteritis (hit 36hrs since first ‘symptoms’ as I woke up for the race). No food in 36hrs and little liquids, but it was the 2nd part of a 3 part series, and since I was winning after the first I just wanted to try and keep myself in the running for the ‘TripleCrown’. With 6min of my time devoted to a porta-potty at mile 8, I was thus quite happy with a 1:31 finish time (14min off my PR).
    However, my body does hate me right now, and if I don’t manage to win the ‘TripleCrown’, I’ll be pretty pissed at my immune system. Only need to run a 1:20 in the last race so the potential is there.

    Thanks for the article!

  13. Jim.
    Great job on the article. Josh, never heard that but makes sense. Another more aggressive way to settle the GI system is to take Imodium ( but not in excess, tricky to balance correctly) early to stop the diarrhea. You can also see if your Doctor will give you a few Zofran oral dissolvable tablets to have. Test it first when you’re well to make sure you tolerate it. Then if you are sick you can take it as a dissolvable tablet on your tongue to reduce or stop the nausea. This will allow you to begin to rehydrate and eat earlier. I agree with pushing sports drinks early, diluted if necessary. Two-3 days of clear urination prior to competing hopefully signal you have done your best. Besides just feeling depleted, lightheadedness should be an important indicator to not compete, or withdraw if you began the event.

    1. My doctors inform me that there’s a reason for gastro, and so unless it’s severe, they refuse to allow medication to combat it. Apparently it’s important to get the infection out of your body, and taking medication means the germs cannot leave your body.

      I’ve asked at least eight doctors, and they’re all repeating basically the same thing. The only exception to the rule is basically if you’re sick enough to need emergency medical care.

      Stick with the charcoal.

  14. Try charcoal.

    One of the best ways to combat, both before and during, a stomach bug is using an all natural remedy, like charcoal. It is super-absorbent, easy to find at your local health food store and it is fast acting, within an hour or two.
    What charcoal does is it soaks up whatever is bugging (pun intended) your stomach, decreasing your nutrient absorption, but more importantly decreasing normal signs and symptoms of gastroenteritis. Emergency rooms across the nation use charcoal as standard protocol for overdose patients for the same sponge-like reasoning, it gets rid of stuff fast.
    Mix a typical dose, 2-3 tablespoons, with your favorite fruit juice, water becomes very gritty and tasteless, and bottoms-up. One word of caution, it leaves a delightful appearance that you’ve been kissing a campfire, so make sure to brush your teeth before resuming daily activities. Best of luck to all of the sick-o’s that have to race, hope this helped a little.

    1. Gastroenteritis involves inflammation of the intestinal lining. A decade ago I had an infection that kept me within ten steps of the bathroom for well over a week. A couple of weeks ago I had another case. I could have taken a bismuth salicylate preparation (e.g., Pepto Bismol) to stop the diarrhea on the first day, but recognizing that diarrhea is the way the body rids itself of pathogens in the intestine, this time I suffered 48 hours, then consumed four 250 mg capsules of turmeric powder over a period of two hours. Within six hours the diarrhea had stopped and I was on the way to recovery, but without constipation. Turmeric is known to be a powerful natural anti-inflammatory and it clearly worked in my case.

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