Thursday, October 28, 2010

Case study: Is exercise bad for the digestive system? (10/29/2010)

Case Study: Is Exercise bad for the digestive system?
Most fitness experts and personal trainers assert that exercise is good for the digestive system. Many nutitionists and physicians support this view. It has been shown, however, that many people develop occasional trouble with their digestive systems after moderate to strenuous exercise. Scientifically conducted surveys recently revealed that approximately 30% of all runners suffer from abdominal cramping during practice or after a race. The immediate need to defecate occurs in 30% of these people. Another 25% develop diarrhea during or just after the race. It is not surprising that strenuous exercise could cause intestinal problems at the time of the activity. After all, the parasympathetic nervous system that controls intestinal activity relaxes during exercise. Some physicians believe that this cuts off blood to the digestive system and may produce discomfort if undigested food is in the stomach or intestines.
Scientists now know that it is not the exercise alone that produces many of the intestinal problems. The surveys show that runners who suffer intestinal cramping very likely have digestive system disorders, such as irritable bowel syndrome or lactose intolerance. Those without any underlying digestive system disorders reported having diets that are probably too high in fiber. Almost half of the runners who deficate after a race have a digestive system function that is modified by exercise. Scientists now believe that the condition humorously called "runners' trots" is caused by decrease in intestinal transit time. Intestinal transit time is the amount of time it takes for food to pass through the digestive system. So far, this explanation is not fully supported by research.
Studies have shown that people who start regular strenuous exercise routines have a decreased average intestinal transit time. People who normally took 35 hours to pass a meal from mouth to rectum reduced their intestinal transit time to 24 hours. The researchers did not take into account any significant changes in diet. Other scientists take the traditional argument that blood flow to the intestines is reduced by approximately 80% during exercise. This loss of blood may cause digestive system abnormalities, such as cramping and diarrhea. Then, there are scientists who believe that dehydration associated with execise could be producing the digestive system disorders.
Use the information in this chapter and the Web sites on page 523 in your book to answer ALL OF the following questions about exercise and digestive system health:
  1. How does the average intestinal transit time affect a person's health?
  2. Is there enough evidence supporting the negative effects of exercise on digestive system function?
  3. Should physicians caution people about exercise given the recent evidence supporting its negative effects on the digestive system?
  4. What warnings about exercise and eating should a personal trainer or physician give to people who are considering an exercise program?
  5. What, if any, actions should be a person take to avoid intestinal problems during exercise?
  6. Should people with preexisting digestive system disorders be discouraged from participating in strenuous exercise?
    • Follow up question to #6: If people were discouraged to exercise, how would that impact their health?
  7. Should the government require people or agencies that promote athletic events or regular exercise to provide warnings about digestive system disoreders associated with the activity? (EXPLAIN your answer)


  1. 1.) The average intestinal transit time affects a person's health by causing problems such as diarrhea, cramping and even obesity.
    2.) I personally think that there is enough evidence to support the negative effects on exercise. It explains the things you develop when strenuous exercising and also explains how people with digestive disorders react while doing strenuous exercise.
    3.) Physicians should tell people about the negative effects of too much exercise, because it can do a lot of damage to your digestive system, and some people may not know that.
    4.) A physician should tell a patient to not eat as much fiber as they do and to exercise, but don't go crazy with it!
    5.) People who want to avoid intestinal problems should eat after they exercise. The food that they eat should contain high proteins and vitamins.
    6.) People who have preexisting digestion system disorders should exercise because it’s good for them. I think that they shouldn’t go crazy and do hardcore exercises, but exercising is good for every human being and they should just control themselves.
    7.) I think that the government should require people who promote athletic events or regular exercise to provide warnings about digestive system disorders, because people may not know that strenuous exercise is not 100% healthy.

  2. 1. It can lead to problems if you have a slow digestive system. It can cause constipation and can make you feel sick. It also can lead to obesity if don’t watch what you eat.
    2. Yes, there are many people suffering from eating disorders such as Anorexia (people who are anorexic can exercise to much) and Compulsive eating (people that compulsively eat may not exercise at all), this changes the rate and speed of your digestive system.
    3. Yes, they should to warn people of the dangers of exercise and also eating disorders that can negatively effect the digestive system.
    4. They should warn them about eating disorders that can develop if they are not eating the right things and not getting the right nutrients and not exercising the right way.
    5. People should eat after they exercise because if they eat before they can develop problems in their digestive system and they should eat foods that are high in vitamins and proteins, so that they don’t starve their body of nutrients.
    6. People should find the exercise that’s right for them, if they have a preexisting digestive system disorder, so that they can still be healthy and not develop other problems.
    If people are discouraged to exercise that can lead to eating disorders were people either eat to much, too little, or not eat at all.
    7. Yes, because it would warn people about the dangers that can develop and negatively effect the digestive system and more people would be healthy. --Nikki Nosal

  3. 1.) If you have a slow digestive track that could mean you have a slow metabolism, this could cause constipation. A fast digestive track could cause diarrhea.
    2.) No, the studies conducted did not take into consideration the participant’s diet.
    3.) I don’t think so because there is not enough valid evidence that suggests that is has an effect on your digestive track. The studies admitted that some of the participants may have had irritable bowel syndrome and lactose intolerance.
    4.) Don’t over use your muscles. This could have a negative affect o n your muscles and possible your digestive track. When exercising stay hydrated.
    5.) Just stay hydrated
    6.) No, they should just monitor how long and intense their work out is.
    7.) Yes, although there is not a significant amount of decent evidence people should know of the possibility of putting their digestive track on the line.

  4. 1. The more time passses, the worse the person's health gets.
    2. Yes, its proven that people who excercise more decrease the intestinal time.
    3. Yes scientist should warn people because that way people will start excersising more and can be more healthy.
    4. Personal trainers should recomend food with a lot of vitamins, proteins, and not fat callories.
    5. High jumping and picking up heavy weights can be a negative for your health.
    6. I dont think that people should be discouraged but i think that they should do whatever they weant to do but they should know what might happen and take a risk for themselfs.
    7. I think the goverment should do that but shouldnt stop people from doing something if they really want to. But before doing something the goverment should explain to the people what might happen if they do a certain activity.

  5. 1. The longer the food is in your digestive system the better you digest it.
    2. No there is not enough evidence to make people stop running.
    3. No they should not because the evidence is inconclusive.
    4. Exercise in moderation. Do not exceed your personal limitations.
    5. Try not to eat right before exercising to avoid stomach cramps and other issues.
    6. They should exercise but if they start to feel symptoms they should take it easy.
    6b. People would become overweight and out of shape.
    7. Yes they should provide warning about digestive disorders brought on by strenuous exercise but they should allow people to choose for themselves whether they should exercise or not.

  6. 1. Studies show that people that are more active, have a faster intestinal transit time and that the more active you are the faster it is. If you have to fast of a intestinal transit time though it could cause cramping, diarrhea, or other problems.
    2. I dont real think so because it said that they dont really take into account the new diets that the people could be on.
    3. I think that if you do have a history of digestive disorders that your doctor should talk to you about the dangers of exercise on your digestive system.
    4. I think that they should warn them of digestive disorders and complicantions that can occur and that they should tell them the right diets that they should be following if they are going to start an exercise program.
    5.I think that you should deffinitly start eating the right foods and that you should make sure you get plenty of water so that your body gets enough water.
    6. I think that they shouldnt do very strenuous just moderate exercises so that they still stay healthy but dont end up hurting themselves.
    7.I think so becuase some people might not know that they could potentially hurting themselves and that people should be more informed about dangers.

  7. 1) The average intestinal transit time affects a person’s health by eating diets or changing eating habits.
    2) Yes, there is enough evidence supporting the negative effects of exercise on digestive system function.
    3) Yes, physicians should caution people about exercise given the recent evidence supporting its negative effects on the digestive system.
    4) Personal trainers should advise people to exercise before eating food.
    5) The person should lots of water and a granola bar during an exercise.
    6) It will impact their health dramatically because if the person doesn’t exercise then the person will gain weight.
    7) Yes because people should know the warnings of digestive disorders of people having it.

  8. 1. well it takes about 34 hours for your food to go through you digestive system and the slower it takes the slower your body gets the nutreants it need to survive and have energy. because the people who have problem after exercise have an actual digestive problem.


    3. yes i do think they should let people know , but not make it a big deal. just put it out there so people dont think their sick that they can just have effects from excersise

    4. well people who are lactose intolerant or have irritable bowel syndrome should watch what they eat before the do an excerise.

    5. well one can rub biofreeze on there stomach to increse their blood floow. scientist think that blood flow goes away from the stomach during exercise.

    6. of course not. being fit is a part of being healthy. there are ways to avoid bad problems during exercise. if people didnt exercise then more and more of the population will be fat.

    7. Yes they should. i think the people should know what can possably harm them. If they dont let the people know they might think it is some other reason why they are geting bad simptoms

  9. 1.) If the average intestinal transit time is good, then that person is healthy. If someone’s average intestinal transit time (ITT) is bad, then they won’t be as healthy. If the ITT average is slow, then the longer of toxic waste matter will be in your stomach and small intestine. If it stays in there long enough, it can damage your small intestine.
    2.) No
    3.) No
    4.) That they should eat healthy and stay hydrated, drink a lot of water. Also, stay warm in all areas of your body.
    5.) People who have intestinal problems should eat after they exercise. So that all the vitamins and minerals, proteins, fats and carbs are already in their system. Also, when people rest after they eat, they won’t really have intestinal problems.
    6.) People that have preexisting digestive system disorders should limit on how intense their workout is. So that they won’t affect the digestive systems.
    6b.) People would be lazy and fat. Not only people that have digestive system disorders but they will have diabetes as well.
    7.) Yes I believe that the government should because people can decide or not if they would like to participate in the event.

  10. 1. When you work out more you have a faster transit time. If it's too fast it could cause cramping or diarrhea.
    2. No, it says they didn't take into account the diets people could be on.
    3. No, exercise is good for you. I think that if you experience these frequent problems you should consult your doctor.
    4. They should let them know about digestive disorders and they should tell them healthy diets to be on that fit their workout plan.
    5.Healthy AMOUNT and TYPE of food. Also, over working yourself isn't always good for you.
    6. I think they should change their workout routines and plans to fit their condition. I think they'd be more unhealthy if they stopped working out.
    7.I think they should, because many people don't even know much or about digestive disorders. They could be feeling the symptoms without even knowing that they're the ones causing the pain. If people were more educated on these disorders I think there would be less problems with the.

  11. 1. If a person digests food slowly then the food would stay in your system longer and a person with a faster digestion will have the food go through the digestive process quickly.
    2. Yes because the study showed that people had problems without changing their diet but doing strenuous activity.
    3. Physicians should warn people that if they start have intestinal abnormalities then it could be a result of their recent start in doing strenuous workouts.
    4. They should not eat a lot of fiber and should drink enough water so that they are hydrated.
    5. Don’t eat before working out and stay hydrated.
    6. They should do workouts that suit them best if a person is able to strenuous workouts without having reoccurring digestive problems then they can do those workouts.
    -People discouraged from exercising will lose the healthy benefits of exercising that people need, so they will become unhealthy and that would probably make their health even worse.
    7. Yes they should but also if you are going to participate in those events then they too should know the risks that come with it. Promoters should warn people about the risk of having problems so that people know what they are getting into.

  12. 1.The average person’s digestion should occur within thirty five hours. If the process is any faster, this may result in digestive disorders such as diarrhea, constipation, or irritable bowl syndrome. These affects commonly occur in people that are more active, since their intestinal transit time is increased compared to the average person. The transit time is very important to one’s health to remain constant, to avoid any bodily discomforts.
    2.No, there has not been enough research to fully support the explanation.
    3.Yes, I think that they should caution people about it, but not scare them resulting into people not exercising anymore.
    4.They should make the person aware of certain side affects that may result from the exercise, but also try to avoid these results by creating a day-by-day based diet and exercise that will not over work your body.
    5.First of all, they should watch what they eat and when they eat. They should just snack before their exercise for a burst of energy, but have a complete meal after their work out. They need to make sure that they are eating well-balanced meals and are getting the right vitamins and nutrients needed for proper digestion. If some of these can not be acquired through the food they eat due to dislike of taste, they must take supplementary vitamins. They should also be properly hydrated and rested.
    6.People should definitely not be discouraged. We need to exercise our bodies to maintain our health. If they have preexisting conditions, they should consult with a physician or a trainer on what would be a good, moderate work out plan for them to not over work their bodies. If people were discouraged to exercise, they would be at more risk for more health problems.
    7.Yes, people should be aware to the negative side affects of exercise. Some people just over work their bodies for exceeding performance or looks, and don’t realize that they could potentially be harming their digestive system so much.