Now, Beaton tries to focus on the positives of his experience. After transitioning from being a vegetarian to becoming a strict vegan, a lifestyle which Moore maintained for fifteen months, he eventually found it difficult to manage alongside his demanding soccer workouts. It never felt like a hassle, because I stood by the cause resolutely and it was worth it to me.

Lastly, Moore touched on the benefits of planning meals. After tearing her ACL last winter, Wilson had been working hard in physical therapy to return to athletics, but was met with a surprising new challenge. Around September and October [of ], I took several naps a day because I was so fatigued all the time.

For Wilson, a change was found within her diet. However, I was so excited by this seemingly tiny accomplishment that I was yelling. I gave all I could give, and accomplished something that I could never have accomplished a few months prior.

I refuse to let that define me in or outside of athletics. Subscribe now to keep reading and get access to the full archive. Type your email….

Continue reading. Skip to content. Like this: Like Loading Secondary navigation Facebook Instagram Twitter Youtube Contact Us Search. Post navigation. Experimental Medicine Vs. Western Medicine. Oyster River Track First Home Invitational. Search for: Begin typing your search above and press return to search.

Press Esc to cancel. Discover more from Mouth of the River Subscribe now to keep reading and get access to the full archive. Type your email… Subscribe. Go to mobile version. These potential risks are worse in adolescence but still present for adults.

Get medical help if you need to lose weight. Be sure to talk to your doctor before making major nutrition changes. People often overestimate the number of calories they burn when training. Avoid taking in more energy than you expend exercising. Also, avoid exercising on an empty stomach.

Every athlete is different, so consider:. If you need to gain or lose weight to improve performance, it must be done safely. If not, it may do more harm than good. Do not keep your body weight too low, lose weight too quickly, or prevent weight gain in unhealthy ways.

It can have negative health effects. This can lead to poor eating habits with inadequate or excessive intake of certain nutrients.

Talk to your family doctor find a diet that is right for your sport, age, gender, and amount of training.

Academy of Nutrition and Dietetics: Sports, Cardiovascular, and Wellness Nutrition, Nutrition Resources for Collegiate Athletes. National Institutes of Health, MedlinePlus: Nutrition and athletic performance. Last Updated: May 9, This information provides a general overview and may not apply to everyone.

Talk to your family doctor to find out if this information applies to you and to get more information on this subject. Getting these other than by mouth is called artificial…. Getting the right amount of water before, during, and after exercise helps your body to function properly.

A lack…. Sugar is a simple carbohydrate that provides calories for your body to use as energy. There are two main…. Visit The Symptom Checker. Read More. Knee Bracing: What Works? Sore Muscles from Exercise. Hydration for Athletes.

Exercise and Seniors. The Exercise Habit. Why Exercise? Exercise: How To Get Started. Home Prevention and Wellness Exercise and Fitness Exercise Basics Nutrition for Athletes.

Calories come in different forms. The main types are carbohydrates, fats, and proteins. Simple carbs fruits, milk, and vegetables are easier for your body to break down. They provide quick bursts of energy.

Complex carbs take longer for your body to break down. They are a better source of energy over time. Complex carbs in whole grain products are the most nutritious. Examples include whole-grain bread, potatoes, brown rice, oatmeal, and kidney beans.

Fat is another important source of calories. In small amounts, fat is a key fuel source. It serves other functions, such as supporting good skin and hair.

Do not replace carbs in your diet with fats. This can slow you down, because your body has to work harder to burn fat for energy. When you can, choose unsaturated fats, like olive oil and nuts.

These are better for your health than saturated and trans fats. Too much fat or the wrong kinds can cause health problems.

It can raise your bad LDL cholesterol level and increase your risk of heart disease and type 2 diabetes. Protein is found in foods like meat, eggs, milk, beans, and nuts.

Some athletes think they should consume large amounts of protein. Over time, too much protein can be harmful to your health. The digestion process can put strain on your liver and kidneys. Know when to eat and rehydrate For athletes, knowing when to eat is as important as knowing what to eat.

Things to consider Athletes require a lot of energy and nutrients to stay in shape. Every athlete is different, so consider: How long before working out is best for you to eat How much food is the right amount for you If you need to gain or lose weight to improve performance, it must be done safely.

Questions to ask your doctor How many calories do I need to eat each day? Should I cut out carbs? Are super restrictive diets healthy for me? Are there any supplements they should take?

This choice is supported by the literature , which suggests that vegetarian and vegan athletes perform just as well in terms of endurance and strength as their omnivorous counterparts.

Following a plant-based diet can have numerous health benefits. Plant-based protein sources, such as tofu, lentils, and beans, have been found to improve circulation, reduce inflammation, lower oxidative stress, promote a healthy gut microbiome, enhance glycogen stores, and support leaner body weights.

However, due to the restrictions of these dietary patterns, following them without proper planning may lead to nutritional deficiencies , such as protein, vitamins B12 and D, iron, zinc, calcium, total calories, and iodine.

These deficiencies may affect performance, recovery, and bone health. In order to maximize a plant-based diet for training and competition, athletes may want to consult with a sports dietitian to ensure adequate nutrient intake and to get well-balanced examples of nutritionally fulfilling meals.

Intermittent fasting, with its varying protocols, involves limiting the time window for eating during the day. This dietary pattern might not be suitable for athletes given their training schedules or the nutrition to fuel performance.

As a result, the potential risks may outweigh the benefits. Limited eating windows may be helpful for weight loss or maintaining a strict weight class, but it can also lead to low energy availability and actually harm performance and overall health.

The pressure to maintain a low body weight for athletics can lead to restrictive diets or even clinical eating disorders, affecting both physical and mental health. These include anorexia nervosa, bulimia nervosa, binge eating disorder, and orthorexia. Athletes , especially those in aesthetics-focused sports such as gymnastics, dance, and ice skating, have the highest rates of disordered eating and eating disorders.

These eating patterns can weaken muscles, cause fatigue, and lead to injuries and complications like anemia and osteoporosis. Restrictive diets like ketogenic, plant-based, or intermittent fasting might appeal to athletes with disordered eating tendencies.

Thus, athletes should carefully assess their motivations for diet changes and consult professionals to ensure their nutritional needs are met.

To summarize, the researchers found that the Mediterranean diet has the most benefits for athletes regarding recovery and performance. Low-carbohydrate and ketogenic diets show no harm to athletic performance; however, the non-ketogenic low-carbohydrate diets that emphasize protein intake might be more sustainable for the energy demands of athletics.

Vegans and vegetarians are at high risk for nutrient deficiencies, especially in nutrients essential for athletic recovery and muscle maintenance. Intermittent fasting may aid weight loss but could hamper athletic performance in endurance and aerobic sports. For any dietary intervention, the reasoning for the change should be closely monitored by the athlete and their healthcare team to ensure disordered eating is not a risk.

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Department of Health and Physical Education, Mount Royal University, Mount Royal Gate SW, Calgary, Alberta, T3E 6K6, Canada. Helios Wellness Centres, Teaching, Research, Wellness Building, Suite , Hospital Drive NW, Calgary, AB, T2N 4Z6, Canada.

Faculty of Kinesiology, University Drive NW, University of Calgary, Calgary, Alberta, T2N 1N4, Canada. University of Calgary, Sports Medicine Centre, University Drive NW, Calgary, Alberta, T2N 1N4, Canada. You can also search for this author in PubMed Google Scholar.

The study was designed by JAP, KAE, and KWJ. All authors contributed to the data collection and entry. Data were analyzed by JAP. Data interpretation and manuscript preparation were undertaken by all authors.

All authors read and approved the final manuscript. Correspondence to Jill A. The Mount Royal University Human Research Ethics Board approved the study ethics ID — All participants provided voluntary, written, informed consent. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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Reprints and permissions. Parnell, J. et al. Dietary restrictions in endurance runners to mitigate exercise-induced gastrointestinal symptoms. J Int Soc Sports Nutr 17 , 32 Download citation.

Received : 19 February Accepted : 04 June Published : 10 June Anyone you share the following link with will be able to read this content:.

Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative. Skip to main content. Search all BMC articles Search. Download PDF. Research article Open access Published: 10 June Dietary restrictions in endurance runners to mitigate exercise-induced gastrointestinal symptoms Jill A.

Parnell ORCID: orcid. Abstract Background Endurance runners frequently experience exercise-induced gastrointestinal GI symptoms, negatively impacting their performance. Methods A questionnaire designed to assess dietary restrictions pre-racing and gastrointestinal symptoms was administered to runners.

Background Gastrointestinal GI symptoms are a common cause of underperformance in athletes, yet are less frequently considered in nutrition recommendations, which focus on fluid, macronutrient, and micronutrient intakes.

Questionnaire The researchers approached participants either at a running clinic, event package pick-up or after completing a running event and asked them to complete a paper version of the questionnaire.

Results Five hundred and thirty runners completed the questionnaire; however, were removed due to reported food allergies or GI associated medical reasons.

Full size image. Table 1 Frequently avoided foods pre-race by gender and athlete age group Full size table. Table 2 Frequently avoided foods pre-race by race distance Full size table. Table 3 Frequently avoided foods pre-race by performance level Full size table.

Editorial team. Nutrition and athletic performance. You are more likely to be tired and perform poorly during sports when you do not get enough: Calories Carbohydrates Fluids Iron, vitamins, and other minerals Protein. However, the amount of each food group you need will depend on: The type of sport The amount of training you do The amount of time you spend doing the activity or exercise People tend to overestimate the amount of calories they burn per workout so it is important to avoid taking in more energy than you expend exercising.

Complex carbohydrates are found in foods such as pasta, bagels, whole grain breads, and rice. They provide energy, fiber , vitamins, and minerals. These foods are low in fat. Simple sugars , such as soft drinks, jams and jellies, and candy provide a lot of calories, but they do not provide vitamins, minerals, and other nutrients.

What matters most is the total amount of carbohydrates you eat each day. A little more than half of your calories should come from carbohydrates. You can satisfy this need by having: Five to ten ounces to milliliters of a sports drink every 15 to 20 minutes Two to three handfuls of pretzels One-half to two-thirds cup 40 to 55 grams of low-fat granola After exercise, you need to eat carbohydrates to rebuild the stores of energy in your muscles if you are working out heavily.

People who exercise or train for more than 90 minutes should eat or drink more carbohydrates, possibly with protein, 2 hours later. Try a sports bar, trail mix with nuts, or yogurt and granola For workouts lasting less than 60 minute, water is most often all that is needed.

PROTEIN Protein is important for muscle growth and to repair body tissues. But it is also a myth that a high-protein diet will promote muscle growth. Only strength training and exercise will change muscle.

Athletes, even body builders, need only a little bit of extra protein to support muscle growth. Athletes can easily meet this increased need by eating more total calories eating more food. Too much protein in the diet: Will be stored as increased body fat Can increase the chance for dehydration not enough fluids in the body Can lead to loss of calcium Can put an added burden on the kidneys Often, people who focus on eating extra protein may not get enough carbohydrates, which are the most important source of energy during exercise.

Amino acid supplements and eating a lot of protein are not recommended. WATER AND OTHER FLUIDS Water is the most important, yet overlooked, nutrient for athletes.

Some ideas for keeping enough fluids in the body include: Make sure you drink plenty of fluids with every meal, whether or not you will be exercising.

Drink about 16 ounces 2 cups or milliliters of water 2 hours before a workout. It is important to start exercising with enough water in your body. Water is best for the first hour. Switching to an energy drink after the first hour will help you get enough electrolytes. Drink even when you no longer feel thirsty.

Pouring water over your head might feel good, but it will not get fluids into your body. Alternative Names.

Exercise - nutrition; Exercise - fluids; Exercise - hydration.

Splanchnic hypoperfusion can result in intestinal ischaemia, which can increase intestinal permeability, heightening bacterial translocation and promoting inflammation [ 6 , 8 ]. High intensity exercise may also decrease gastric motility and emptying [ 1 , 10 , 11 , 12 ]. This cascade of physiological events can increase the potential for nutrient malabsorption [ 9 ] further aggravated by extreme environmental conditions [ 13 , 14 ].

Nutritional factors surround food selection of an athlete prior to exercise and have the potential to reduce or exacerbate exercise-induced GI symptoms yet remain largely unstudied.

Broadly, endurance runners are advised to determine their own pre-exercise food intolerances with general advice to avoid foods high in fat, protein, and fiber, as well as limit concentrated sources of carbohydrates [ 15 , 16 , 17 ]. Evidence for the benefit of a low fermentable oligosaccharides, disaccharides, monosaccharides and polyols FODMAP diet to reduce exercise-induced GI symptoms is emerging [ 19 , 20 , 21 ]; however, there remains a paucity of research in pre-exercise nutrition.

Dehydration is believed to aggravate symptoms [ 9 ], whereas others suggest gut-training via carbohydrate ingestion during running may be beneficial [ 22 ]. Mechanical factors include the motion of the sport [ 1 , 8 ]. Finally, psychological factors should be considered: as an association between exercise-related GI distress and stress and anxiety has been reported [ 7 ].

Considering that individuals will most easily be able to control nutritional factors, the purpose of this study was to assess voluntary, pre-exercise food restrictions related to running-induced GI symptoms and differences related to gender, age, performance level, and event.

Athletes were recruited from running groups, races, and at pre-race events across southern Alberta. to limit confounding variables. These individuals will be assessed separately in future publications.

Those who reported a specific food intolerance were removed from the analysis of that particular food to ensure that the food avoidance was related to exercise and not a general aversion; however, were included in the remainder of the analyses.

The study received ethical approval from the Mount Royal University Human Research Ethics Board ethics ID — All participants provided written, informed consent. The researchers approached participants either at a running clinic, event package pick-up or after completing a running event and asked them to complete a paper version of the questionnaire.

The questionnaire was developed to collect information on basic demographics, running experience, medical conditions, voluntary food restrictions, exercise-induced GI symptoms experienced if they consume a trigger food, reasons for avoiding foods, and sources of information.

The questionnaire asked participants to select options for each question by checking boxes. A copy of the questionnaire is available in supplemental file 1. We also recruited a small number of participants from running clinics, in which case participants may not have been competing in events despite training for running.

Information is presented as the number and percentage of total athletes. Five hundred and thirty runners completed the questionnaire; however, were removed due to reported food allergies or GI associated medical reasons.

If a participant chose not to answer a question e. gender , their answers to the remaining questions were included in the analyses. Pre-race food avoidances in runners to minimize exercise-induced GI symptoms.

Percentage of endurance runners who avoid a food category pre-race to minimize GI symptoms. Significant differences were found in milk products and energy drinks, which were more commonly avoided in younger athletes.

Masters males had the lowest avoidance of chocolate; whereas, young males were the most likely to avoid the milk alternatives and lactose-free milk Table 1.

The most commonly avoided foods by event in the pre-race period are presented in Table 2. Multivariable regression modeling did not detect any interactions except for high-fiber, as noted previously.

Frequently avoided food by performance level pre-racing are presented in Table 3. Conversely, competitive athletes were less likely to avoid coffee or tea Table 3. Symptoms experienced while racing. Symptoms that runners reported they would experience during a race if they consumed a food that they would typically avoid.

Data is presented as percentage of all runners. Pre-racing, young females suffered from exercise-induced GI symptoms more frequently than other groups. No other symptoms during racing were associated with running distance after adjusting for gender, age, and performance level in the analysis.

Reasons for avoiding foods are provided in Fig. The most common reasons listed for food avoidances included personal experience and personal preference. Reasons for pre-race food avoidances in runners. Reasons endurance runners choose to avoid a food pre-race.

Our research provides insight into voluntary pre-exercise food restrictions endurance runners use to mitigate GI symptoms, via a fully powered, reliable and validity tested questionnaire.

Furthermore, we controlled for GI disorders, allergies, and food intolerances. Finally, we have representation from a diverse group of runners, allowing for increased specificity in our understanding of food avoidances.

Foods most commonly avoided were milk products, high protein, high-fiber, chocolate, and caffeinated beverages, aligning with recommendations to limit protein, fat, and fiber [ 15 , 16 , 17 ] while concurrently highlighting the need for more in-depth research. Importantly, each food item is a complex mix of macro and micronutrients as well as other bioactive ingredients that can impact GI symptoms; thus, caution is advised when making conclusions regarding an individual nutrient in a food.

Generally, the higher the performance level, the more likely an athlete was to restrict food, which is likely a function of increased GI symptoms with increasing exercise intensity [ 8 , 25 ].

Another possibility is that higher level athletes are more experienced and therefore more familiar with aggravating foods. Avoidance of milk and milk products was common among runners in our study. Dairy products are complex foods and naturally contain lactose.

We are in agreement with others who have demonstrated that athletes will remove sources of lactose; a high FODMAP food, from their diet to improve GI symptoms [ 27 ].

Not all dairy products contain lactose, therefore, future research should subdivide this category into lactose containing and lactose-free products. Considering that lactose-free milk was also among the top foods avoided, the reasoning is likely multifaceted.

Dairy products are also sources of fat and protein, which are thought to promote exercise-induced GI symptoms [ 16 ]. Further analysis indicated that young females were most likely to avoid milk products followed by young males, which is in agreement with other findings indicating age as a negative predictor for dairy consumption, in the general population [ 28 ].

Our research suggests that age remains a predictor for dairy avoidance in sport, even when allergies and intolerances are considered. Further, Yantcheva et al. The role of dairy in mucus production has not been fully elucidated [ 29 ]; however, it clearly remains a popular perception.

Foods typically considered high protein, especially animal protein, were commonly avoided pre-exercise. Athletes are advised to avoid excessive protein pre-exercise [ 16 ]; however, recommendations for the appropriate amount of protein and studies regarding the effects of protein intake on exercise-induced GI symptoms in runners are lacking.

Tiller et al. They do note that protein intake during specifically ultra-endurance running may positively affect energy metabolism and mitigate muscle damage with the caveat that the results are equivocal. Snipe et al.

A reduction in intestinal epithelial injury and intestinal permeability was found with both whey protein and glucose; however, gut discomfort and gastrointestinal symptoms were higher with protein.

The aforementioned studies support our conclusions regarding protein rich foods and increased exercise-induced GI symptoms. Given the potential performance benefits of protein in the pre-exercise meal and popularity of high-protein diets, additional research is required to determine if there is a threshold below which symptoms are minimal.

Generally, the higher the performance level, the more likely athletes were to avoid high protein foods, possibly due to increased GI symptoms with increased exercise intensity [ 8 , 25 ]. Runners avoided high-fiber foods, which aligns with others describing lower intakes of dietary fiber by endurance runners, although not specifically in the pre-exercise meal [ 32 , 33 ].

Limiting of dietary fiber pre-exercise is advised [ 16 , 17 ], based largely on a study by Rehrer et al. Dietary fiber ingestion is associated with decreased splanchnic vascular resistance resulting in increased splanchnic vasodilation and splanchnic flow.

These physiological effects oppose blood flow needs during exercise, where there is prolonged splanchnic hypoperfusion, and consequently may present as abdominal disturbance [ 35 ]. Delayed gastric emptying with viscous dietary fibers [ 36 ] may also play a role, further exacerbated by high intensity exercise [ 37 ].

Conversely, insoluble fibers stimulate peristalsis via fecal bulking [ 36 ], which may promote urge to defecate or diarrhea. Fiber restriction was more common in longer distances, which may reflect changes in GI transit time, as diarrhea was reported more frequently in longer distances.

Finally, many fiber rich foods are high FODMAP foods, which may provide another mechanistic explanation. Dietary fibers are heterogeneous and vary in their physiological effects; thus, recommendations should consider fiber type in addition to quantity.

Further, given the health benefits of adequate fiber and recent advances in the understanding of the importance of the gut microbiota in athletes [ 6 ], research is required regarding pre-exercise timing strategies to optimize intakes while minimizing GI symptoms.

Dark chocolate has been proposed as an ergogenic aid via increased nitric oxide [ 38 ]; however, caution should be advised given our results of high avoidance pre-race, although we did not distinguish between the different types of chocolate.

Chocolate has been described as a food item that provokes GI disturbance, particularly constipation [ 39 ], although research in athletes is lacking. Chocolate contains several biologically active compounds including cocoa, caffeine, and fat; thus, the mechanisms are unclear.

It is known, however, that high fat foods may aggravate exercise-induced GI symptoms [ 16 ]. Coffee and tea represent another food group often avoided and morning caffeine intake has been associated with increased GI symptoms in the lower gut of triathletes [ 40 ].

Future research should consider the effects of coffee, tea, and herbal infusions separately as they contain different constituents and can result in different physiological effects.

Energy beverages are a cocktail of vitamins, sugars, and plant extracts, especially stimulants. GI upset is included in the list of commonly reported symptoms after energy drink use [ 42 ] and safety is a concern [ 43 ].

Energy drinks were restricted more often in younger athletes; however, they are a relatively new product and marketing of energy drinks is typically youth oriented. It is possible that older athletes would not report avoiding energy drinks if they were unfamiliar with the product.

GI disturbance during runs is a common concern as described here and throughout the literature [ 1 , 7 , 8 , 9 ].

At a minimum, GI symptoms associated with exercise are related to mechanical forces, altered GI blood flow, changes in the GI mucosal activity, neuroendocrine changes, and stress [ 1 , 4 , 7 , 8 , 9 ].

Female runners were more likely to experience urge to defecate and diarrhea. Further, others support a higher prevalence of GI symptoms in female athletes [ 3 , 22 , 45 , 46 ]. Conversely, in a trial to determine the effect of biological sex on GI symptoms during exertional-heat stress, by timing testing during the follicular phase of the menstrual cycle, no differences in GI symptoms were reported except for flatulence and abdominal stitch, which were higher in males [ 47 ].

The aforementioned findings suggest further research is required to determine the causes of increased symptoms in females and the potential relationship to sex hormones and female gut physiology.

The higher prevalence of symptoms in younger athletes is confirmed by the literature [ 44 , 45 , 46 ]. Increased age may protect against GI symptoms due to diminished splanchnic vasoconstriction via reduced catecholamine response and consequently increased oxygen supply [ 44 ].

Further, increased age often reflects increased running experience, which is associated with fewer GI symptoms [ 44 , 45 ]. Considering performance level, it was often the lower recreational athletes who were least likely to report symptoms.

Potentially these athletes are competing at lower intensities, thus have fewer symptoms, as GI symptoms are reported to increase with exercise intensity [ 8 , 25 ].

Symptoms are thought increase with distance [ 2 ], however, studies are required, and are likely compromised by the tendency to consume food and fluid during the longer events.

In our study, diarrhea increased with the longest distances run after controlling for other factors. When the reasons for food avoidances were explored, the majority of the participants relied on personal experience or personal preference.

Further investigation into their sources of information and how this varies by age, gender, event, and performance level is of interest. A limitation to the study is its observational nature, which precludes any causal conclusions.

Conversely, the study does highlight candidate foods for future clinical trials, as it is not feasible to test every food in a controlled study.

People can usually achieve adequate intakes of essential vitamins and minerals by eating a varied, balanced diet. Some athletes may choose to take vitamin or mineral supplements or ergogenic aids, such as creatine.

The ISSN recommends that consumers evaluate the validity and scientific merit of claims that manufacturers make about dietary supplements. There is little evidence to support the efficacy or safety of many dietary supplements, including:. However, scientists have shown that other ergogenic aids, such as caffeine and creatine monohydrate, are safe and effective for athletes.

It is important to be aware that some athletic associations ban the use of certain nutritional supplements. Moreover, athletes should ensure they maintain adequate hydration. Given that sweat losses are a combination of fluids and electrolytes, such as sodium and potassium, athletes may choose to and benefit from using sports drinks, milk , or both to meet some of their hydration needs.

The ISSN suggests that athletes training intensely for 2—6 hours per day 5—6 days of the week may burn over — calories per hour while exercising. As a result, athletes engaging in this level of activity may require 40—70 calories per 1 kg of body weight per day, compared with the average less active individual, who typically requires 25—35 calories per 1 kg of body weight daily.

According to the ISSN, athletes weighing 50— kg may require 2,—7, calories per day. It also notes that athletes weighing — kg may need to consume 6,—12, calories daily to meet training demands.

The timing and content of meals can help support training goals, reduce fatigue, and help optimize body composition. Guidelines for the timing and amount of nutrition will vary depending on the type of athlete. For example, the ISSN advises strength athletes consume carbohydrates and protein or protein on its own up to 4 hours before and up to 2 hours after exercise.

The American College of Sports Medicine ACSM also notes the importance of consuming protein both before and after exercise for strength athletes. By contrast, endurance athletes would need to consume mostly carbohydrates and a small amount of protein roughly 1—4 hours before exercise.

Both the ISSN and ACSM emphasize the role of meal timing in optimizing recovery and performance and recommend athletes space nutrient intake evenly throughout the day, every 3—4 hours. Some people may find that consuming meals too close to the beginning of exercise can cause digestive discomfort.

It is therefore important to eat an appropriate amount and not exercise too quickly after eating. People who are training or racing at peak levels may find it challenging to consume enough food for their energy requirements without causing gastrointestinal GI discomfort, especially immediately before an important workout or race.

For example, the ISSA highlights the importance of hydration and carbohydrate loading for competitive swimmers. At the same time, it emphasizes consuming easily digestible carbohydrates, such as bananas and pasta, prior to events to avoid GI discomfort. Athletes may need to work with a sports nutritionist, preferably a registered dietitian , to ensure they consume enough calories and nutrients to maintain their body weight, optimize performance and recovery, and plan a timing strategy that suits their body, sport, and schedule.

Athletes need to eat a healthy and varied diet that meets their nutrient requirements. Choosing whole grains and other fiber -rich carbohydrates as part of a daily diet generally promotes health.

However, immediately prior to and during intense trainings and races, some athletes may prefer simpler, lower fiber carbohydrates to provide necessary fuel while minimizing GI distress. The following is an example of what an athlete might eat in a day to meet their nutritional needs.

Breakfast: eggs — either boiled, scrambled, or poached — with salmon , fresh spinach , and whole grain toast or bagel. Lunch: stir-fry with chicken or tofu, brown rice , broccoli , green beans , and cherry tomatoes cooked in oil.

Dinner: a baked sweet potato topped with turkey, bean chili, or both, served with a watercress , peppers, and avocado salad drizzled with olive oil and topped with hemp seeds. Snacks are an important way for athletes to meet their calorie and nutrition needs and stay well fueled throughout the day.

Options include:. Athletes need to plan their diet to optimize their health and performance. They should consider their calorie and macronutrient needs and ensure they eat a varied diet that provides essential vitamins and minerals.

Hydration and meal timing are also vital for performing well throughout the day. Some athletes may choose to take dietary supplements. Options include milk, water, percent fruit juice and sport drinks.

However, realize that sport drinks and percent fruit juice tend to be higher in overall sugar content and, in the case of fruit juice, lack many of the health benefits present in its whole food counterpart.

Also, be sure not to confuse sports drinks such as Gatorade with "energy" drinks such as Red Bull and similar beverages. Stick with whole food options as much as possible as opposed to highly processed foods.

Without adequate calories from the healthiest food sources, you will struggle to achieve your performance goals. Plan a nutritious meal by choosing at least one food from each category.

Healthy fat. Adequate hydration is a key element in sports performance. Most athletes benefit from developing a personal hydration plan.

A general rule for training is to consume a minimum:. Four to six ounces of fluid every 15 minutes of exercise. To properly assess, weigh yourself immediately prior to and after a workout. For every pound of weight lost, replace with 16 ounces of fluid. Best hydration choices include water, low-fat milk or percent juice.

Sports beverages are best reserved for competition, where quick hydration and electrolyte replacement are necessary. There are a few golden rules when it comes to eating on game day:.

It happens the days, weeks, and months leading up to the competition. Peak performance during competition means eating nutritious food while traveling. Relying on the concession stand for food during competition is an almost certain failure.

Players and parents should prepare by packing a variety of food and beverages. Choose energy-packed foods such as whole grain crackers with low-fat cheese, tortilla wraps with veggies and lean meat, hard-boiled eggs, vegetable or bean soups, small boxes of non-sugary cereal, fresh fruit, mini-whole wheat bagels with peanut butter, pita bread with hummus or pasta with grilled chicken.