References for all blogs about Exercise and Pregnancy

References
1. American College of Sports Medicine. Guidelines for exercise testing and prescription, 5th edition. Baltimore: Williams & Wilkins: 2006.

2.Clapp, J.F. The effects of maternal exercise on early pregnancy outcome. Am J Obstet Gynecol, 1989; 161: 1453-7.

3.Clapp, J.F. Exercising through your pregnancy. Omaha, Nebraska: Addicus: 2002.

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21.Clapp, J.F., Kim, H., Burciu, B., & Lopez, B. Beginning regular exercise in early pregnancy: effect on fetoplacental growth. Am J Obstet Gynecol, 2000; 183: 1484-1488.

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25.Madsen, M., Jorgensen, T., Jensen, M.L., Juhl, M., Olsen, J., Anderson, P.K., et al. Leisure time physical exercise during pregnancy and the risk of miscarriage: a study within the Danish National Birth Cohort. BJOG, 2007; 114: 1419-1426.

26.Saftlas, A.F., Logsden-Sackett, N., Wang, W. Woolson, R., & Bracken, M.B. Work, leisure-time, physical activity and risk of preeclampsia and gestational hypertension. Am J Epidmiol, 2004; 160: 758-765.

27.Sorenson, T.K., Williams, M.A., Lee, I., Dashow, E.E., Thompson, M., & Luthy, D.A. Recreational physical activity during pregnancy and risk of preeclampsia. Hypertension, 2003; 41: 1273-1280.

28.Rafla, N.M. The effect of maternal exercise on umbilical artery blood flow in pregnancy-induced hypertension. Journal of Obstetrics and Gynaecology, 2000; 20: 19-23.

29.American College of Sports Medicine. American College of Sports Medicine (ACSM) offers guidance on physical activity during pregnancy and the postpartum period. 2006.

30.Wang, T.W. & Apgar, B.S. Exercise during pregnancy. American Family Pysician, 1998; 57.

31.Milunsky, A., Ulcickas, M., Rothman, K.J., Willett, W., Jick, S.S., & Jick, H. Maternal heat exposure and neural tube defects. JAMA, 1992; 268: 882-885.

32.Miller, P., Smith, D.W., & Shepard, T.H. Maternal hyperthermia as a possible cause of anencephaly. The Lancet, 1978; 519-520.

33.Shiota, K. Neural tube defects and maternal hyperthermia in early pregnancy: epidemiology in a human embryo population. American Journal of Medical Genetics, 1982; 32: 281-288.

34.Jones, R.L., Botti, J.J., Anderson, W.M, & Bennett, N.L. Thermoregulation during aerobic exercise in pregnancy. Obstetrics & Gynecology, 1985; 65: 340-345.

35.Clapp, J.F., Wesley, M., & Sleamaker, R.H. Thermoregulatory and metabolic responses to jogging prior to and during pregnancy. Medicine and Science in Sports and Exercise, 1987; 19: 124-130.

36.Clapp, J.F. The changing thermal response to endurance exercise during pregnancy. Am J Obstet Gynecol, 1991; 165: 1684-1689.

37.McMurray, R.G. & Katz, V.L. Thermoregulation in pregnancy implications for exercise. Sports Medicine, 1990; 10: 146-158.

38.Katz, M. & Sokal, M.M. Skin perfusion in pregnancy. Am J Obstet Gynecol, 1980; 137: 30-33.

39.Artal, R. & O’Toole, M. Guidelines of the American College of Obstetricians and Gynecologists for exercise during pregnancy and the postpartum period. British Journal of Sports Medicine, 2003; 37.

40.Clapp, J.F. The course of labor after endurance exercise during pregnancy. Am J Obstet Gynecol, 1990; 163: 1799-1805.

41.Beckmann, C.R. & Beckmann, C.A. Effect of a structured antepartum exercise program on pregnancy and labor outcome in primiparas. J Reprod Med, 1990; 35: 704-709.

42.Kardel, K.R. & Kase, T. Training in pregnant women: effects on fetal development and birth. Am J Obstet Gynecol, 1998; 178: 280-286.

43.Bungum, T.J., Peaslee, D.L., Jackson, A.W., & Perez, M.A. Exercise during pregnancy and type of delivery in nulliparae. JOGNN, 2000; 29.

44.Dye, T.D., Knox, K.L., Artal, R., Aubry, R.H., & Wojtowycz, M.A. Physical activity, obesity, and diabetes in pregnancy. Am J Epidemiol, 1997; 146: 961-965.

45.Clapp, J.F. Fetal heart rate response to running in midpregnancy and late pregnancy. Am J Obstet Gynecol, 1985; 153: 251-252.

46.Hauth, J.C., Gilstrap, L.C., & Widmer, K. Fetal heart rate reactivity before and after maternal jogging during the third trimester. Am J Obstet Gynecol, 1982; 142: 545-547.

47.Spinnewijn, W., Lotgering, F.K., Strujk, P.C., & Wallenburg, H. Fetal heart rate and uterine contractility during maternal exercise at term. Am J Obstet Gynecol, 1996; 174: 43-48.

48.Kennelly, M.M., McCaffrey, N., McLoughlin, P., Lyons, S., & McKenna, P. Fetal heart rate response to strenuous maternal exercise: note a predictor of fetal distress. Am J Obstet Gynecol, 2002; 187: 811-816.

49.Rafla, N.M. & Cook, J.R. The effects of maternal exercise on fetal heart rate. Journal of Obstetrics and Gynaecology, 1999; 19: 381-384.

50.Jovanovic, L., Kessler, A., & Peterson, C.M. Human maternal and fetal response to graded exercise. J Appl Physiol, 1985; 58: 1719-1722.

51.Clapp, J.F., Simonian, S.J., Harcar-Sevcik, R., Lopez, B., & Appleby-Wineberg, S. Morphometric and neurodevelopmental outcome after exercise during pregnancy. Medicine and Science in Sports and Exercise, 1995; 27: S74.

52.Clapp, J.F., Lopez, B., & Harcar-Sevcik, R. Neonatal behavioral profile of the offspring of women who continued to exercise regularly throughout pregnancy. Am J Obstet Gynecol, 1999; 180: 91-94.

53.Kardel, K.R. & Kase, T. Training in pregnant women: effects on fetal development and birth. Am J Obstet Gynecol, 1998; 178: 280-286.

54.Clapp, J.F., Simonian, S., Lopez, B., Appleby-Wineberg, S., & Harcar-Sevcik, R. The one-year morphometric and neurodevelopmental outcome of the offspring of women who continued to exercise regularly throughout pregnancy. Am J Obstet Gynecol, 1998; 178: 594-599.

55.Clapp, J.F. Morphometric and neurodevelopmental outcome at age five years of the offspring of women who continued to exercise regularly throughout pregnancy. J Pediatr, 1996; 129: 856-863.

56.Hacker, N.F. & Moore, J.G. Essentials of obstetrics and gynecology, 3rd edition. Philidelphia: W.B. Saunders Company: 1998.

57.Pivarnik, J.M., Clark, S.L., Cotton, D.B., Spillman, H.T., & Miller, J.F. Cardiac output responses of primigravid women during exercise determined by the Direct Fick Technique. Obstet Gynecol, 1990; 75: 954-959.

58.Sady, S.P., Carpenter, M.W., Thompson, P.D., Sady, M.A., Haydon, B., & Coustan, D.R. Cardiovascular response to cycle exercise during and after pregnancy. J Appl Physiol, 1989; 66: 336-341.

59.Erkkola, R.U., Pirhonen, J.P. & Kivijarvi, A.K. Flow velocity waveforms in uterine and umbilical arteries during submaximal bicycle exercise in normal pregnancy. Obstet Gynecol, 1992; 79: 611-615.

60.Marieb, E.N. Human Anatomy & Physiology. San Francisco: Benjamin Cummings: 2001.

61.Lotgering, F.K., Van Doorn, M.B., Struijk, P.C., Pool, J., & Wallenburg, H.C. Maximal aerobic exercise in pregnant women: heart rate, O2 consumption, CO2 production, and ventilation. J Appl Physiol, 1991; 70: 1016-1023.

62.McMurray, R.G., Hackney, A.C., Katz, V.L., Gall, M., & Watson, W.J. Pregnancy-induced changes in the maximal physiological responses during swimming. J Appl Physiol, 1991; 71: 1454-1459.

63.Berry, M.J., McMurray, R.G., & Katz, V.L. Pulmonary and ventilatory responses to pregnancy, immersion, and exercise. J Appl Physiol, 1989; 66: 857-862.

64.Calguneri, M., Bird, H.A., & Wright, V. Changes in joint laxity occurring during pregnancy. Annals of the Rheumatic Diseases, 1982; 41: 126-128.

65.Karzel, K.P. & Friedman, M.C. Orthopedic injuries in pregnancy. Exercise in pregnancy, 1991; ed. Artal, R.A., Wiswell, R.A., & Drinkwater, B.L. Baltimore: Williams & Wilkins.

66.Shauberger, C.W., Rooney, B.L., Goldsmith, L., Shenton, D., Silva, P.D., & Schaper, A. Peripheral joint laxity increases in pregnancy but does not correlate with serum relaxin levels. Am J Obstet Gynecol, 1996; 174: 667-671.

67.Davies, G.A., Wolfe, L.A., Mottola, M.F., & MacKinnon, C. Joint SOGC/CSEP clinical practice guideline: exercise in pregnancy and the postpartum period. JOGC, 2003; 129: 1-7.

68.Pate, R.R., Pratt, M., Blair, S.N., Haskell, W.L., Macera, C.A., Bouchard, C., et al. A recommendation from the Centers for Disease Control and Prevention and the American College of Sports Medicine. JAMA, 1995; 273: 402-407.

69.Glenn, N., Davies, G., Charlesworth, S., & Wolfe, L. Prolonged exercise in late gestation-maternal responses. Am J Obstet Gynecol, 2003; 189: S196.

70.Clapp, J.F. & Little, K.D. The effect of endurance exercise on pregnancy weight gain and subcutaneous fat deposition. Medicine and Science in Sports and Exercise, 1995; 27: 170-177.

71.ACOG Committee. Opinion no. 267: exercise during pregnancy and the postpartum period. Obstet Gynecol, 2002; 99:171-173.

Vitamin D, are you deficient?

Before I begin today's post, I just want to inform you of something new I'm going to add to my blog. Every Monday will be "Motivational Monday!" So at the bottom of every Monday post, you will find a phrase or sentence that gives you another reason to lead a healthy life. My hope is that you will find these to be good reasons to exercise and eat better; and use them to help motivate you through your week (and weekend!). I'd love to hear your thoughts if you have any!!


Recently, there has been a lot of research centering around vitamin D deficiency and how it impacts our health. If you’ve been wondering what the deal is, this will give you a general idea of what is going on and what you should do to make sure you’re not missing out on a vital nutrient!

Vitamin D deficiency is real and affects many Americans. According to the NHANES III study, when men, women, white Americans, African Americans, and Hispanics were evaluated and compared, it was found that the prevalence of Vitamin D deficiency was at least 40% for all groups. African Americans in the age group of 20-39 years old had the highest prevalence nearing 100%. White Americans in the same age category had the lowest prevalence of vitamin D deficiency, which was about 40%. (Martins D, et al. Arch Intern Med 2007 June;167:1159-1165)

So why are we having such a problem with vitamin D deficiency? There are many factors to blame. One difference between our culture today and our culture 50 years ago is that we use sunscreen, and a lot of it! I am not saying that is a bad thing! I am no expert on this subject, but I definitely believe that wearing sunscreen is a smart move. Vitamin deficient or not, I want my family’s skin protected! Other factors are air pollution, skin tone, less time spent outside, and poor diet. Many other factors can play into vitamin D deficiency, but they are more specific to some diseases.

Being deficient in vitamin D isn’t just something to fluff off and not worry about. Individuals who are deficient are more likely to die of heart failure or sudden cardiac death. Also, adequate vitamin D is thought to protect against hypertension (high blood pressure).

Ameri P, Ronco D, Casu M, Denegri A, Bovio M, Menoni S, Ferone D, Murialdo G. High prevalence of vitamin D deficiency and its association with left ventricular dilation: An echocardiography study in elderly patients with chronic heart failure. Nutr Metab Cardiovasc Dis. 2010 Apr 14.)

Pilz S, Tomaschitz A, Drechsler C, Dekker JM, März W. Vitamin D deficiency and myocardial diseases. Mol Nutr Food Res. 2010 Mar 29.

Vitamin D deficiency also increases cancer risk, particularly colon, breast, and prostate. Inflammatory and autoimmune diseases, in addition to metabolic disorders are also more likely to occur in those who are deficient. Insulin-dependent diabetes falls into the category of autoimmune diseases.

Peterlik, M., Cross, H.S.. Vitamin D and calcium deficits predispose for multiple chronic diseases. European Jour of Clin Invest, 2005 Apr 28.

Vieth, Bischoff-Ferrari, Boucher, Dawson-Hughes, Garland, Heaney, et al. The urgent need to recommend an intake of vitamin D that is effective. Am J of Clin Nut, 85(3), 643-650: 2007.

The first thing you should do if you have not had your vitamin D level tested is to speak with your doctor. Your serum level of vitamin D can be easily tested and your doctor can then advise you on the next step. Your level may be fine! However, if it is not, you may need to take a supplement in order to achieve a safe level. If your doctor prescribes some time in the sun unprotected, I would encourage you to speak with your dermatologist to get his or her opinion on such a plan. Do not begin taking any kind of supplement without getting your level tested and being advised by a doctor!

Some food sources of vitamin D are wild salmon, canned tuna or mackerel, shitake mushrooms, cod liver oil, and fortified cheeses and milk.


MOTIVATIONAL MONDAY!
Staying fit gives me the energy I need to play with my children/grandchildren!

Feeding Your Baby.....Jarred or Homemade Food?

To make your baby food at home, or buy it in a jar…that is the question! Both options are ultimately fine choices, but there are pros and cons to both sides. Keep reading for a discussion about your options.

Jarred baby food bought at the store is not overly inferior to homemade baby food, although it is probably not quite as rich in some vitamins and minerals. This is due to the heating of jars, possible over-cooking and sitting on a shelf for some time. So, your baby may not get quite as much nutrition from the jarred food, but there isn’t a detrimental difference in homemade food and jarred. You shouldn’t feel that your baby is being deprived if you don’t have the time to cook your own food at home. If you do have time to steam fruits/veggies and puree them, which is not as time consuming as it seems, you may feel good about the fact that you are probably putting a more nutrient dense food on your child’s spoon.

Often times, making baby food is significantly cheaper than buying food in a jar. You can buy an inexpensive sweet potato and make a couple of weeks worth of baby food, freeze it, and pull it out, as you need it. When I did this, I always liked to calculate exactly how much I was saving because that always made me happy! However, I recently realized that you could also purchase baby food at very cheap prices, sometimes free! If you purchase baby food when it is on sale and use coupons, you’ll be amazed at the deals you get.

A definite con when it comes to store-bought baby food happens when you start your baby on stage 2 and 3 foods. I was really disappointed when I saw things like “Turkey and Green Beans”; however, I found something very different on the ingredient label. I would often see “sweet potatoes” as the first and most abundant ingredient. Sometimes the vegetable listed on the front of the jar, was the very last ingredient on the list! If I see the words “turkey” and “green beans” on a label, I expect those to be the prime ingredients. Instead, the mixture is sweetened so that we can continue to teach our children to only enjoy sweet foods. It is important for children to get a taste of vegetables and meat so that they can learn to enjoy those flavors as well.

On another note, while I found it very easy to turn fruits and vegetables into yummy foods for my baby, I didn’t have the same luck with meats. Whenever I made chicken, it turned into a crumb that my child wasn’t ready for. He really needed something smoother that he didn’t have to chew.

With all of these pros and cons, what should you do? It is really up to you! However, I'll tell you what I did. For my child, I served a mix of homemade baby food and some store-bought. I really enjoyed and felt good about cooking his foods fresh in my own kitchen. However, when I was able to get jarred food at a great price, I stocked up on meats that were mixed with whole grains. I typically stayed away from the meats mixed with a conglomerate of fruits and vegetables, unless I saw that the vegetable that I was looking for was at the top of the ingredient list. I found that when we were out and about, sometimes the jarred food was very convenient. However, I also put my homemade food in a little container and brought it with us on occasions.

If you’re wanting to start making your own baby food, but are unsure of where to begin, I recommend “Cooking For Baby” published by William Sonoma. It has great recipes for babies and toddlers. The toddler recipes are great for the whole family too! Just beware that you should follow your pediatrician or registered dietitian’s advice about when to introduce foods. Do not go by the advice of any cookbook or book that is not written by an appropriate health professional!

Exercising with Diabetes

If you are one of the many Americans with diabetes choosing to exercise, good for you! This can benefit you in many ways including reducing your hemoglobin A1c (an indicator that gives insight to blood sugar levels over a three month period), increase insulin sensitivity, and decrease risk for heart disease. Here are some recommendations from the American College of Sports Medicine for diabetics to keep in mind while exercising.

Check your blood sugar before exercise. If blood sugar is above 250 mg/dL, do not exercise until the level comes below 250 mg/dL. If blood sugar is less than 100 mg/dL, have a snack containing 10 to 20 grams of carbohydrate.

Keep an exercise log. On this log, record your pre-exercise blood sugar level, the time of day, medication/insulin administered, type of exercise, duration of exercise, and intensity level. Over time, this will help you to gain a better understanding of how certain types of exercise impact your blood sugar level.

Plan ahead. Knowing what type of exercise and how much you will do can help you to adjust any medications and insulin. Also, carry a 10 to 15 gram carbohydrate snack with you to eat/drink approximately every 30 minutes.

Adjust insulin dosages. Short- or rapid-acting insulin can be reduced by 50% to avoid hypoglycemic episodes. Be sure to get your doctor’s approval for this.

Exercise with a friend. This is especially important when beginning an exercise routine until blood sugar response is better known.

Wear a diabetic identification tag. Hopefully this would never be needed, but you wouldn’t drive a car without insurance, so don’t exercise without your tag! If something were to happen, this would help you to receive better care by anyone attending to your needs.

Wear comfortable shoes appropriate for activity. This helps to prevent injury.

Check your feet! Always do this whether you exercise or not. However, it is probably even more pertinent after exercise. You need to look for sores or any irritated spots and show them to your doctor if they occur.

American College of Sports Medicine. Guidelines for exercise testing and prescription, 5th edition. Baltimore: Williams & Wilkins: 2006.

Go ahead, eat the chocolate!

You liked that title, didn’t you? Sometimes we all get a craving for something less than healthy. If you think about it for days in and days out, aren’t you going to go crazy? You’re human and you shouldn’t be deprived of all of the things you love! In fact, I believe that when we deprive ourselves and feel deprived, we go overboard at some point eating more than “just a nibble” of our favorite, unhealthy foods.

If you are eating healthy 90% of the time, there is no reason that you can’t partake in a little indulgence here and there. Maybe if you let yourself have a little nibble of what you really enjoy, you won’t feel the need to go overboard because you know you can have it again soon. It all goes back to the old saying “everything in moderation”.

I just want to be clear that I’m not saying that is okay to eat a huge bowl of ice cream, quarter pounder cheese burger, French fries, and a bag of chips all in one day. This would be considered "going overboard". I’m just talking about small indulgences that satisfy your cravings. So, go ahead and enjoy!

A More In-Depth Explanation of Why Eating Often is Beneficial

Recently, a question came up from a reader on another website (go here to read the full post) about the validity that you should eat 3-6 meals daily. This individual referred to an article written in The New York Times touting that there is really no benefit to eating frequently. Instead of responding, knowing full well that some people just have their minds made up, I decided to post on my blog giving information to back up the reasoning behind frequent meals.

1. To be clear, I stated in my post that a minimum of 3 meals should be eating each day. The studies mentioned by The NY Times compared 3 meals to 6 meals. I do not believe that eating only 3 meals is detrimental; however, less than 3 meals is damaging. Not only for the reasons of increased fat storage and depletion of glycogen, but also because people overeat when they are deprived for long periods during the day. I have seen this in practice over and over again. I have had hundreds of patients who go all day without eating, and then tell me that they are so ravenous by the end of the day that they eat everything they can find. I have had some patients find that they are consuming several thousand calories in the evening. So yes, while the end result is calories in versus calories out, a) you are more likely to metabolize more calories per day with more frequent meals; and b) people who eat less than three times per day, typically eat more calories than they need in a day in one or two sittings.

2. Magazines, Newspapers, and other media present the research how they would like to present it. There is always a way to take portions of a study out of context and bend it to appear how you would like it. The people who write these articles are not always qualified to interpret research and advise others on it. Sometimes, the articles are written simply for “interesting reading”. To decide whether or not to take heed, check their credentials.

2. I did take a look at The NY Times article and the research that it was referring to. Notice that the author also mentioned a scientific study that did, in fact, show a metabolic advantage to eating small frequent meals. ( Jenkins, Wolever, Vuksan, Brighenti, Cunnane, Rao, Jenkins, Bucklye, Patten, Singer, et al. Nibbling versus gorging: metabolic advantages of increased meal frequency. N Engl J Med. 1989 Oct 5;321(14):929-34.) Part of the story is that, in science, many studies will be conflicting, so it takes a lot of analysis and MANY scientific studies before conclusions can really be drawn. To be honest, after looking at all three of the studies mentioned in the article, I don’t believe any of them were well designed. They all include an extremely small amount of subjects and they all look at different outcomes. Unfortunately, I was also unable to pull up the entire studies; however, looking at the abstract is much more telling than a line or two in The NY Times. However, I have a few more comments on the two studies that “disproved” the need for small frequent meals. One of the studies gave every subject the same amount of calories. Everyone surely does not have the same caloric needs; therefore, you will have some people consuming more than necessary and others consuming less. How can you conclude anything from that? The other study was only conducted for two weeks and it did, in fact, show a decrease in fat oxidation. Overall, it looks like better studies need to be completed.

3. Regardless of the fact that the above-mentioned studies were really not conducted well, classic studies do show that resting energy expenditure is, in fact, decreased during prolonged periods of not eating. In the first 24 hours of starvation, glycogen stores are depleted, so there is no “fat melting away”. Glycogen is stored with water, so when glycogen is used up, water loss occurs. This leads to…….weight loss! But not fat loss! Fat loss occurs in the later stages of starvation. In the early stages of starvation, fat is preserved. (Barton. Nutrition support in critical illness. Nutr Clin Pract 9: 127. 1994) Another study shows that resting metabolic rate does drop by as much as 15% within 2 weeks of inadequate food intake. (Ravussin, Swinburn. Effect of caloric restriction and weight loss on energy expenditure. In: Wadden TA, Van Ittalie TB (eds.) Treatment of the Seriously Obese Patient. New York: Guilford Press, 1992.)

4. When you are not eating often, you can think of insulin release like hills and valleys. This is unfortunate because it causes large fluctuations in blood sugar, which is not healthy for organs. Also, when insulin is peaking due to a large influx of food after fasting, fat storage is promoted.

Hopefully this post helped to clear up any possible confusion!

Cross-training is important....

1. To prevent boredom. Let’s face it; sometimes you need a little change! By switching up your workout often, hopefully you can keep interesting.

2. To prevent injuries. Because your body is moving in different ways with various types of exercise, so do your joints and muscles. Variation gives certain parts of your body a little rest and; therefore, decreases your risk for injury.

3. To make you a better athlete and make you more fit. Working muscles differently allows you to strengthen your “weakest link”, if you will. Always exercising the same way will only strengthen certain muscles, and only in a particular way. Changing up your routine allows you to challenge your muscles.

4. To possibly get you through a weight-loss plateau. When you exercise in one mode, whether it is running, walking, or riding your bike, your body becomes very efficient at that task. Challenging your body to a different type of exercise may allow you to burn more calories.

5. To find your favorite types of exercise. You never know if you’ll like something until you try it. You may just find out that you like biking better than running. However, you’ll never know if you only run!