Skip navigation

Q. Help! What’s the solution to intestinal problems during long runs?


A. Upset stomachs, nausea, cramping, and urgency to take a pit stop are common problems among long distance runners. Because each person has his or her personal response to long runs, I can only ask you lots of questions, but perhaps they will help you find an answer. Here goes...


• Are you running too far, too fast too soon and your body is telling you it isn’t ready for that distance?

• Are you stressed and anxious on long-run days, and your nerves are creating the problem?

• Do you eat too much food the night before? If so, try having your big meal at brunch the day before and eat lighter at night.

• Do you eat too much breakfast before the long run? Try eating part of the breakfast the night before, at bedtime, so you’ll be less hungry in the morning.

• Do you eat fatty, heavy foods (like a sausage, egg ‘n cheese biscuit) before the long run?

• Do you drink too much pre-run coffee?

• What do you use for fuel during the long runs? Gels sometimes cause GI problems. So can commercial sports drinks or candies with the wrong kind of sugar for your gut.

• Are you chewing sugarless gum? The sweetener (sorbitol) can cause GI distress such as gas and diarrhea.

• Do you eat yogurt, kefir, or take probiotics? They can help resolve bowel issues.

• Do you get dehydrated? Lack of fluids contributes to diarrhea.

• Do you eat a high fiber diet? “Healthy” diets with abundant whole grains, fruits and veggies can become problematic for some runners.

• Is the problem limited to during runs or do you have intestinal issues at other times of the day? Perhaps you have latent Irritable Bowel Syndrome that gets aggravated during long runs?

• Do other people in your family have intestinal issues, like constipation, diarrhea, bloating, or colon cancer? Perhaps you have problems digesting gluten (a genetic tendency) and should be tested to see if you have Celiac Disease?

• Have you kept food logs to track potential culprits so you can pinpoint, or at least narrow down, the problem?


Good luck being a food detective! And don’t hesitate to seek medical advice if all of the above suggestions fail to find a solution. A consultation with a local sports dietitian for a nutrition check-up can be very helpful! See for a referral network.


Please add your comments if you have found a solution not mentioned above!

5,220 Views 0 Comments Permalink Tags: running, nancy_clark, pre-exercise_food, diarrhea, constipation, runner's_trots, intestinal_problems_in_runners


Here’s your chance to update your sports nutrition knowledge while enjoying an information-packed workshop with two internationally known professionals:


Sports nutritionist Nancy Clark MS, RD, CSSD is respected for her skills with helping athletes and exercisers enhance their performance and achieve their desired physiques.


• Exercise physiologist WilliamEvans PhD is renown for his research on protein, exercise, and aging—plus his ability to translate that information into “how to” tips.


This 1.5-day program is designed to help both health professionals as well as serious athletes. You’ll find answers to your questions about how to--

--improve athletic performance with a winning sports diet.

--manage weight issues and resolve disordered eating practices.

—invest in lifelong health for longevity

--further your athletic and/or professional career.


Ten hours of education for ACE, AFAA, AND, ACSM, CHES, NATA, NSCA.


“I was surprised to learn new information on a topic I thought I knew so well.”

            --Registered dietitian/personal trainer, Seattle




St. LOUIS:  Nov 16-17 at St. Louis University


CHICAGO:  Nov 30-Dec 1 at Rush University


COLUMBUS:  Jan 25-26, 2013 at Ohio Health Riverside Campus


INDIANAPOLIS:  Feb. 8-9 at National Institute for Fitness and Sport


ONLINE:  Every day!

You’ll listen to the speakers’ voices and see their PowerPoint presentations. Almost as good as being there in person!


Please visit for more details.



NOTE: If you live near any of the workshop locations, please share this announcement with coaches, athletic trainers, personal trainers,dietitians, nutrition educators, and yes, serious athletes themselves.

1,446 Views 0 Comments Permalink Tags: nancy_clark, sports_nutrition_workshop, william_evans, nutrition_ceus, online_education, athletes_food

An estimated 0.6% of Americans have a peanut allergy and need to avoid peanuts. Thanks to the Food Allergen Labeling and Consumer Protection Act, peanuts—and other top food allergens including milk, eggs, treenuts, shellfish, wheat, and soy—must be listed on food labels. Be sure to read those labels—especially on commercially baked goods including granola and protein bars.


What can kids eat to replace peanut butter?

     almond butter, cashew butter or other nut butters (if no allergies to tree nuts),

     sunbutter (from sunflower seeds)

     soynut butter.


Hummus and low fat cheese are other options that, like peanut butter, are convenient, easy to make into a sandwich, and are inexpensive.


In schools, educating kids and parents is preferable to banning peanuts and peanut butter, because bans can give a false sense of security. Students need to be taught:

     • do not share food.

     • do not bring peanut-containing foods into classroom activities (like birthday parties).

     • do not eat on the bus.

Schools can set aside an allergen-free table in the cafeteria.


Researchers are currently trying to figure out if early introduction of peanuts in childhood is preferable to avoidance, and if kids with allergies can become more tolerant by being given small amounts of peanuts over the course of months and years until they can safely tolerate a standard serving.


For more ideas:

989 Views 0 Comments Permalink Tags: peanut_butter, allergy, peanuts, food_allergy, peanut_allergy

Nancy, which brand of amino acids should I buy? On, there are 16 brands, ranging in price from $18 to $40. Help…!”


Answer: What makes you think you even need to buy essential amino acids? You can easily get them in protein-rich foods like eggs, yogurt, milk, chicken—any animal-based protein has all the essential amino acids your body needs.


The protein supplement industry has done an excellent job of making consumers believe they need to buy essential amino acids. Wrong! If you fuel-up your workouts with a protein+carb combination, such as a yogurt and banana, and then recover afterwards with another protein+carb combination such as lowfat chocolate milk followed by real foods at the next meal, you’ll be doing a fine job of getting all of these building blocks of protein. Rest assured, you could more wisely spend your money on protein-rich foods, not amino acid supplements, and get the results you want from your workouts.


Just to define the “lingo”: Proteins are made from many amino acids, just like words are made from many letters. Some of these amino acids— the essential amino acids—need to come from food, because the body cannot make them.


Here are a few ways to get two of the essential amino acids, isoleucine and leucine. Because pure amino acids taste nasty, I’ll get mine from yummy chocolate milk and real foods at meals any day!



Protein source                                    Isoleucine            Leucine

                                                             grams                  grams


Chocolate milk, 16 oz                            1.2                           1.9

Tuna, 6 oz can                                      2.0                           3.5 

Cottage cheese, 1 cup                           1.6                           2.9

Met-Rx Whey Protein, 1 scoop               1.4                           2.3



For more information, refer to the chapter on protein in: Nancy Clark's Sports Nutrition Guidebook

4,644 Views 0 Comments Permalink Tags: nancy_clark, sports_nutrition, chocolate_milk, amino_acids, protein_supplements, recovery_foods, branch_chain_amino_acids

If your skinny high school son is pestering you to buy a weight gain supplement because he’s sure it will create bulging muscles by breakfast, think twice and save your money!

As you can see from the chart below, all weight gain supplements are expensive and offer nothing you cannot get via food. A hefty peanut butter and jelly sandwich and a tall glass of milk aids weight gain at a far lower price tag than an equal amount of calories from Muscle Milk.


Food-home based             Calories         Price                   Cost/100 calories

Granola (1 cup) +              500               $1.00                       $0.20

8-oz 2% milk


Sandwich: PB & J             650               $0.95                       $0.15

(3 Tbsp PB, 2 Tbsp J)


Chocolate milk, 16-oz        300               $0.60*                      $0.20


Instant breakfast               250               $0.80                        $0.32


Grape Juice, 16-oz            280               $1.00                        $0.36


Muscle Milk, powder         310               $1.78                        $0.57


Drinks-on the run

Nesquick, 16-oz bottle       300               $1.79                        $0.60

Ensure, 8-oz bottle            250               $1.75                        $0.60

Muscle Milk, 14-oz bottle   230               $3.59                        $1.56


As you can see, buying bottles of read-to-drink meal replacements can quickly get expensive.


A money-saving alternative is to make your own weight gain drink:

In the morning, blend 1 quart of 2%-milk with 4 packets of Carnations Instant Breakfast and 1/2 cup powdered milk (1,000 calories total). Toss in a banana or other fruit for more calories. Drink half at breakfast and take the rest with you in a travel mug. Yummier than most commercial products—and no vitamin-fortified taste or smell.


Spend your food budget wisely!



For additional information, read the chapter on on to gain weight healthfully in Nancy Clark’s Sports Nutrition Guidebook.

2,083 Views 0 Comments Permalink Tags: nancy_clark, gain_weight, build_muscle, weight_gain_supplements, skinny_athletes

Among my clients, I’ve observed that skinny athletes who have trouble gaining weight tend to be good fidgeters. They twiddle their fingers, swing their legs backand forth while sitting, and seem unable to sit still. All this involuntary movement burns calories. In comparison, the folks who complain about their inability to lose weight generally sit calmly, barely blinking their eyes. They may complain they have a “slow metabolism.” Doubtful. Their metabolism is likely normal, but their propensity to sit calmly is the problem. Compared to the fidgeter, they save themselves a lot of calories!


The technical term for the spontaneous movement often seen in skinny people who have difficulty gaining weight is Non-Exercise ActivityThermogenesis or N.E.A.T. NEAT includes not only fidgeting but also pacing while you talk on the phone and standing (not sitting) while you talk with a teammate. If you overeat, activation of NEAT helps you dissipate excess energy by nudging you to putter around the house more, choose to shoot some hoops, or (yikes!) feel motivated to vacuum and clean the house. If your body’s ability to activate NEAT is low, then you likely gain weight easily. NEAT can predict how resistant you'll be to gaining weight.


If you are overfat, the next time you start to complain about your slow metabolism, think again. Maybe you should start fidgeting and moving more throughout the daytime?

If you are skinny, the next time you complain about being unable to gain weight, think again. Can you try to stop fidgeting and pacing?


Be well,




For help with gaining weight: Nancy Clark’s Sports NutritionGuidebook, Chapter 14: Add Bulk, Not Fat



Levine JA, Ebernath NL,Jensen MD. 1999. Role of nonexercise activity thermogenesis in resistance tofat gain in humans. Science.283(5399):212-4.

1,781 Views 0 Comments Permalink Tags: nancy_clark, how_to_gain_weight, fidget, difficulty_gaining_weight, skinny_athlete, neat
Nancy Clark RD CSSD

Nancy Clark RD CSSD

Member since: Jul 8, 2007

Hi! I specialize in nutrition for exercise, and help active people figure out how to manage food, weight, exercise, energy and enjoyment of eating. Let me know if you have any questions!

View Nancy Clark RD CSSD's profile