Exercise and Thyroid Health
Published September 22 2014
Just about everyone reading this understands that regular exercise is important for optimal health. While I’m sure many people reading this article are following a regular exercise routine, other people rarely exercise. Some people live a sedentary lifestyle not because they choose to do this, but perhaps they don’t have the energy to exercise, or they might have a lot of pain and therefore can’t exercise without the pain increasing. While many people with hypothyroid conditions don’t have the energy to exercise, many with hyperthyroid conditions refrain from exercising due to the cardiac symptoms, such as a high pulse rate and palpitations. During this article I plan on talking about how much people should exercise, the type of exercise they do, how exercise affects the immune system, and of course how exercise directly affects thyroid health.
But what I’d first like to do is discuss some of the benefits of exercise. Most people realize that exercise benefits cardiovascular health, as it can result in a reduction in incidence of and mortality from coronary artery disease, help with weight loss, reduce stress and anxiety, can help to increase bone density, and it has other benefits as well. On the other hand, physical inactivity will increase the risk of cardiovascular disease and other chronic conditions such as diabetes, obesity, hypertension, osteoporosis, depression, and even cancer.
Overexerting Yourself Can Cause More Harm Than Good
Although most people agree that regular exercise is important, many aren’t aware that too much exercise can be harmful for their health. The problem is that most people don’t know when they are overexerting themselves. Later in this article I’ll discuss the specifics with regards to how exercise affects the immune system, and this will allow you to better understand the negative effect that exercise can have on your health if you’re not cautious. Although the duration of exercising is something to pay attention to, one of course also needs to consider the type of exercise routine. For example, I recently purchased a treadmill desk, and I’ll spend many hours each day walking on the treadmill while working on my computer. However, because I walk at a very slow pace it doesn’t put much stress on my immune system, and it’s healthier than sitting behind a desk all day. Of course one can argue that there are negative consequences associated with walking on a treadmill for prolonged periods of time, such as increased exposure to electromagnetic fields (EMFs). But just as is the case with everything else you need to weigh the risks vs. benefits, and I personally think there is greater risk of sitting down all day when compared to being exposed to the EMFs from a treadmill, although perhaps I’ll be proven wrong about this in the future.
Besides spending plenty of time on my treadmill desk, I also go to the gym a few days per week to exercise, and recently I saw this man who was on the stationary bike who was having a very intense aerobic workout. Although there’s nothing wrong with intense cardiovascular exercise for short period of times, this person was clearly overexerting himself, as he was cycling hard and breathing heavily for at least twenty minutes. And this wasn’t an isolated incidence, as I’ve seen the same person overexert himself on other occasions when visiting the gym. I’m pretty sure I was guilty of this a number of years ago before I was diagnosed with Graves’ Disease, as I enjoyed going on the rowing machine at the time, and I would spend thirty minutes each time on this machine and I would have a pretty intense workout. But when I think back I realize that I was probably pushing myself too hard.
I’m not discouraging anyone from having an intense workout, but if you’re “going all out” then it really is important to limit the duration to no longer than a few minutes. I’ll discuss this shortly when I talk about high intensity interval training. Just to clarify, I’m not saying that you can’t do aerobic exercise for longer than thirty minutes, as while I don’t go on the rowing machine these days, I do go on a stationary bike for thirty minutes and have a pretty good workout. But at no time while doing continuous aerobic exercise am I out of breath, as I can hold a conversation with someone throughout my exercise routine.
What Type of Exercise Should You Do?
At this point you might be a little bit confused, as while you should understand that you don’t want to exercise too intensely for prolonged periods of time, you still might not know what type of exercise you should do. I’m going to specifically discuss exercise in hypothyroidism and hyperthyroidism shortly, but for now I’d like to focus on three types of exercise. Keep in mind that this isn’t all-inclusive, and although I’m not going to talk about stretching I do think it’s important for everyone to do both pre- and post-stretching.
Short-term high intensity interval training. More and more people are becoming familiar with the benefits of short-term high intensity exercise. There are different names for this type of exercise, and one of the common names is “burst training”. Short-term high intensity interval training involves repeatedly exercising at a high intensity for 30 seconds to several minutes, separated by one to five minutes of recovery (1). High intensity intermittent exercise can help with insulin resistance (2) (3), and as a result it can be very effective in reducing total abdominal fat, subcutaneous fat, and abdominal visceral fat in obese women (4). It can also help to reduce oxidative stress and improve antioxidant status (5).
As for what type of high intensity interval training you should do, there are numerous options. You can use a treadmill, stationary bike, or a rowing machine. And if you don’t have access to any exercise equipment then you still can do high intensity interval training . For example, you can go outside and do some sprints, or use some stairs. So for example, you can do thirty second sprint, followed by four minutes of light walking, followed by another thirty second sprint, etc. There are numerous variations of high intensity interval training routines, and if this is new to you then it really is a good idea to work with a certified personal trainer for at least one or two sessions in order to make sure you do this correctly.
Continuous Aerobic exercise. Although some will argue that if you do short-term high intensity interval training that there is no need for regular aerobic exercise, I disagree. Research clearly shows the long-term health benefits of aerobic exercise, and so I recommend doing both high intensity exercise and some aerobic exercise. As I mentioned earlier, I spend a lot of time on my treadmill desk, but I also go to the gym three to four times per week for thirty minutes of aerobic exercise. Although I can increase the speed of my treadmill and do some higher intensity (although not too intense) aerobic exercise at home, since I go to the gym to do some strength training (which I’ll discuss next), I do some aerobic exercise while I’m there.
Strength training. I think it’s important for just about everyone to do some strength training at least two to three times per week. Now when I say “strength training” this doesn’t necessarily mean heavy weightlifting. In fact, for many people reading this I would recommend to do some light weightlifting. Others can do more moderate weightlifting. I’m not going to discuss what you specifically should do, but you want to try working out all of the major muscle groups on a weekly basis, and if this isn’t something you’re currently doing then it probably would be best to hire a personal trainer, even if it’s only for a few exercise sessions.
To summarize, I recommend for most people to do all three types of exercise I mentioned here. I do a few minutes of high intensity exercise three days per week, and I also do some moderate aerobic exercise three or four times a week, and I do some strength training two to three times per week. In addition to this I spend many hours per week on my treadmill desk.
I’m not recommending for everyone reading this to begin exercising immediately. As I just mentioned, if you haven’t been participating in a regular exercise routine then it would be wise to work with a personal trainer for a few sessions. Some people continue working with a personal trainer on a regular basis, as not only does it ensure that their technique is correct when lifting weights, but it also serves as a method of keeping motivated. In addition, if you have any type of cardiovascular condition then it probably would be a good idea to check with your medical doctor before beginning any exercise routine.
How Does Exercise Affect The Immune System?
I’d now like to talk about how exercise affects immune system health. This information will benefit everyone, but especially those with autoimmune thyroid conditions such as Graves’ Disease and Hashimoto’s Thyroiditis. Regular exercise has been associated with enhanced vaccination responses, lower numbers of exhausted/senescent T-cells, increased T-cell proliferative capacity, lower circulatory levels of inflammatory cytokines, increased neutrophil phagocytic activity, lowered inflammatory response to bacterial challenge, greater natural killer cell cytotoxic activity and longer leukocyte telomere lengths in aging humans (6). Overall, regular exercise seems to have a healthy effect on the immune system, as regular aerobic exercise appears to be associated with a reduction in chronic inflammation (7). Since regular exercise has a positive effect on the immune system and can help to reduce chronic inflammation, then this would suggest that it could benefit those with autoimmune thyroid conditions such as Graves’ Disease and Hashimoto’s Thyroiditis.
On the other hand, acute exercise can have a negative effect on immune system health in a number of different ways. First of all, overtraining syndrome results in suppressed immune function, and can cause an increase in upper respiratory tract infections (8). I’ve spoken about secretory IgA in another article entitled “How Does Secretory IgA Relate To Thyroid Health?“, and I discussed how this lines the gastrointestinal tract, and serves as protection against pathogens. Well, prolonged exercise and intensified training can cause decreases in secretory IgA (9). So if someone is exercising too hard then this can suppress their immune system, making them more susceptible to developing an autoimmune thyroid condition.
However, exercise also affects the cytokines. I’ve put together a separate article entitled “The Role of Cytokines In Autoimmune Thyroid Conditions“, and in this article I spoke about the Th1 and Th2 pathways, and how Hashimoto’s Thyroiditis is usually a Th1 dominant condition, whereas Graves’ Disease is considered to be a Th2 dominant condition. Each of these pathways is characterized by different T helper lymphocytes, as Th1 lymphocytes are associated with cell-mediated immunity and the killing of intracellular pathogens, while Th2 lymphocytes are associated with humoral immunity and antibody production (8). Why is this important? Well, overtraining can drive the development of a Th2 lymphocyte profile (8). As a result, if someone has a genetic marker for Graves’ Disease and overexercises, then this overtraining can serve as a trigger.
So if someone currently has Graves’ Disease then without question they want to make sure they don’t overexert themselves. However, remember that exercising excessively also can decrease secretory IgA, and this can be a factor with BOTH Graves’ Disease and Hashimoto’s Thyroiditis. Just keep in mind that I’m talking about excessive exercise, as doing moderate exercise is of course healthy, and as I mentioned earlier, it can actually result in a decrease in inflammation.
How Does Exercise Affect Thyroid Health?
Thyroid hormones are important regulators of energy metabolism, and while some studies show that the thyroid hormones are only transiently or insignificantly changed during strenuous exercise (9), other studies have shown that maximal aerobic exercise greatly affects the level of circulating hormones (10), causing the T4, Free T4, and TSH to rise at 90% of maximum heart rate, while the rate of T3 and Free T3 decreased. However, another study showed that maximal treadmill exercise didn’t greatly affect the concentration of circulating thyroid hormones (11). Another more recent study looked to compare the thyroid hormone responses to high-intensity interval exercise and steady-state endurance exercise (12). This study showed that immediately after exercising the thyroid hormone levels were significantly elevated in both the high-intensity interval exercise group and the steady-state endurance exercise group. 12 hours after exercise the thyroid hormone levels were normal in the steady-state endurance exercise group, but in the high-intensity interval exercise group the free T3 was significantly reduced, while the reverse T3 was significantly elevated, and so there was a suppressed conversion of T4 to T3, which suggested that a longer recovery period is necessary for hormone levels to normalize with high-intensity interval exercise.
So what does all of this information mean? Should those with thyroid and autoimmune thyroid conditions engage in endurance exercise? Is high intensity exercise still okay to do? Or should those people with these conditions hold off on exercising? Well, it really does depend on the person and the condition, and so I’d like tie everything together and discuss whether people with different types of thyroid and autoimmune thyroid conditions should exercise, and if so, what type of exercise is best for them.
Exercise, Hypothyroidism, and Hashimoto’s Thyroiditis. Ideally the person with hypothyroidism or Hashimoto’s Thyroiditis will want to do some short-term high intensity exercise three days per week, and I also recommend at least 30 minutes of moderate aerobic activity three to five days per week, along with some light weight lifting two to three days per week. Once again, if you’re not already in a workout routine I would recommend hiring a personal trainer, even if it’s only for one or two sessions. However, many people will experience fatigue due to low thyroid hormone levels, anemia, a chronic infection, or other factors, and therefore they might not be able to do any high intensity exercise, and might also struggle with any type of aerobic exercise, including light walking. When this is the case I think it’s important not to push yourself, especially after I discussed how overexerting yourself can have a negative effect on your health. So if someone has low energy levels then I would hold off on doing the high intensity exercise, try to do at least ten to fifteen minutes of aerobic exercise a few days per week, and to also try doing some light weightlifting twice per week. Then as your energy levels improve you of course can increase the intensity and duration of exercise, although even when you reach this point you still want to make sure not to overexert yourself.
Exercise, Hyperthyroidism, and Graves’ Disease. Most people with hyperthyroidism and Graves’ Disease need to be very cautious when it comes to exercising. Although not everyone with a hyperthyroid condition experiences cardiac symptoms such as a high pulse rate and heart palpitations, many people do. So when this is the case I would recommend avoiding the high intensity interval training, and I would probably limit the aerobic exercise to some light walking a few times per week. Many people with hyperthyroid conditions can do some light weightlifting a few times per week, and it can be important to do this to help with the bone density. Of course as one’s health improves the person with hyperthyroidism will eventually be able to increase the intensity and duration of their exercise, but I would recommend working with someone. Although a personal trainer can be beneficial to work with, especially when it comes to helping you with the light weightlifting, it probably would be wise to also work with a healthcare professional for some guidance.
So hopefully you have a better understanding about the different types of exercise, and how exercise affects both the immune system and thyroid health. Regular exercise can also help people to sleep better, help to improve mood, and can also increase bone density. Although I recommend high intensity interval training, continuous aerobic exercise, and some strength training, not everyone with thyroid and autoimmune thyroid conditions will be able to do all of these. For example, some people won’t have the energy to exercise, and many people with hyperthyroid conditions will need to avoid doing any high intensity exercise, and might also not be able to do much continuous aerobic exercise either. For those who aren’t currently exercising on a routine basis I would highly suggest hiring a personal trainer, even if it’s only for a few sessions.