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CDC CFS Patient-Centered Outreach and Communication Activity (PCOCA) Conference Call

The CDC Chronic Fatigue Syndrome (CFS) Patient-Centered Outreach and Communication Activity (PCOCA) Conference Call was held on Monday, January 14, 2013.

Meeting Highlights

Nancy Klimas, M.D. is a clinical immunologist and the Director of the Institute for Neuro-Immune Medicine, Nova Southeastern University. She has been in the field of CFS for over 25 years, and was one of the first people to advocate for a biological understanding of CFS. Connie Sol, Ph.Dc. is a Clinical Exercise Physiologist at the Institute for Neuro-Immune Medicine and the USA Triathlon Federation Head Coach for high performance Paratriathlon (triathlon aspect of Paralympics). She has been working with aerobic reconstruction for sport performance in the context of Multiple Sclerosis in the last 9 years. They presented a talk titled "Redefining Exercise in CFS through Reconstruction of Aerobic Capacity," on January 14, 2013, as part of the Patient Centered Outreach Communication Activity (PCOCA) series.

Dr. Klimas: I feel that I am a perfect advocate to talk about exercise in CFS and I understand that many CFS advocates and patients are well aware that exercise is a "dirty word" in our field. However, exercise is a dirty word mainly because of public policy, and not all from this country. Some people had thought that exercise and exercise alone was the only thing one could do for this illness, but I am here to tell you that exercise alone is not the only thing to do; instead, it is one of many things. But exercise is not to be ignored. A pivotal moment for me was when I was doing an NIH funded study with blood volume in CFS patients. We knew that the autonomic nervous system was playing such an important role in how bad people felt. So we conducted a study to increase blood volume and then did tilt table testing and exercise physiology research to look at what happens in people with CFS before and after the exercise intervention.

Our research with 100 patients and 100 controls made an important observation that deconditioning explained much of the dysautonomia in CFS. Not only is deconditioning a player but a huge player, and it is connected to many other things that are going on in CFS. Another pivotal study that we conducted is with Connie Sol looking at exercise as a challenge deliberately put into play to look at the mediators of relapse that are in the day-in and day-out of people with CFS.

We put people on an exercise bike and had them ride to the level of their maximum capacity. When people go past their aerobic capacity they move from a threshold into an anaerobic state in which they have to draw more energy from their cells to keep on exercising. That is the threshold of relapse and this is where CFS patients have major problems. As part of the study, we measured blood 9 times over 24 hours. And we measured 500,000 genes to see what is being turned on and off in response to exercise. We are trying to connect the dots to understand what may come first to trigger the cascade of events that cause a relapse, as it turns out there are a series of bad things going on that we can identify. We use the bike exercise test to challenge the autonomic system and we found by a peak of exercise of 8 minutes they are already releasing inflammatory cytokines. These cytokines will then go to affect a host of other things, so that at the end of the day you have pain, oxidative stress, endocrine regulatory defects, energy problems, and inflammation.

The first step in relapse is the autonomic challenge and the second step is the inflammatory result. One would think because I'm an immunologist that I would jump on the immune system first but in fact, I look at the autonomic and deconditioning first. Because if I can help the autonomic nervous system, then we may be able to prevent many of the normal day in and day out triggers that cause that daily relapse in CFS patients. By using this approach we see significant improvement in our clinical patients.

I've been working with Connie Sol on the science and asked her to come into our clinic to see if she could work on the practical things that we could give as tools to patients such as to improve on aerobic capacity and general conditioning. By measuring people's aerobic threshold and then seeing where they may lie, we can bring people into a better practical state of fitness.

If you wake up with adrenaline going through your body, and your pulse is going before you got out of bed and it races more every time you try to do the smallest thing, you are kicking off an adrenaline response all day long. The normal parasympathetic/sympathetic response is disrupted by having the adrenaline signaling all the time. The gut needs some time with the parasympathetic system (time when adrenaline is quiet) to digest food. This is one reason why people with CFS have irritable bowel syndrome (IBS) and other disorders of the GI tract. And how can you sleep when you are rushing through an adrenaline rush? But if you add an inflammatory trigger, that further affects the quality of sleep.

One mistake people make when talking about exercise in CFS is to say 20 minutes of exercise per day would make you better. But no, you would be on your back, you would be sleeping for the next 3 weeks. The key is to understand your personal limit and this becomes important to give you the best possible advice on reconditioning and then good advice on how to go about doing that. I do believe that re-training in aerobic and anaerobic activities are both important in getting back to the best you can be.

Dr. Sol: I have worked with Dr. Klimas for a few years in the area of exercise to see what we can do to improve quality of life for CFS patients. My background comes from training athletes with multiple sclerosis (MS). If you look at the studies in the last 10 years on exercise and MS, the results show that exercise is good for MS patients and helps to increase aerobic capacity. MS and CFS have a lot of similarities in the terms of autonomic dysfunction and deconditioning. When we first discussed what we could do for CFS patients, I understood that we had to stop looking at exercise as running or walking in the context of chronic illness. Exercise for some of our patients means literally when you first get up in the morning and walk around. Activities of daily living are an exercise because in many cases they are going to raise their heart rate to a toxic level, which is something we would like to avoid. By redefining these activities as exercise we are able to structure a program to build tolerance starting with small physical activities that will lead to eventually having a better quality of life. It doesn't happen immediately – it takes 3 months to see any changes and this is because our approach is slow. I don't want the patient to tell me that they felt anything after or during activities because if they do feel something, then it is likely the onset of a symptom. If they tell me, "I didn't feel anything, should I be doing more?" that is when I know that amount is right.

There are two different types of metabolism: aerobic and anaerobic. Aerobic metabolism uses stored fats as a fuel source and produces the energy where most people live their daily lives. An active person lives 85% of their day within this aerobic capacity. A person, who is healthy but sedentary, lives about 65% in this capacity. In CFS patients, with the deconditioning that comes from the forced sedentary lifestyle, tend to live life at less than 65% of their aerobic capacity, relying on their anaerobic metabolism to provide energy. Anaerobic metabolism uses stored carbohydrates as a fuel source and is a system is meant to be a back-up or emergency system, it is not meant to be our primary source of energy for normal everyday daily activities.

We can tell if a person is moving from an aerobic to an anaerobic condition by observing the gas exchanges during the exercise study and at the same time taking note of the heart rate at that point. The heart rate, then, becomes an important threshold measure. By observing the heart rate we found that most of the day a CFS person is in an anaerobic state, at a point that triggers the release of cytokines, and then the feeling of malaise. Once we can find the threshold point, we work to get the patient to stay within the zone using a pulse monitor. In CFS, as in other chronic illness, there seems to be a dysfunction where a body chooses to use fat or carbohydrates as a fuel source when processing energy. I see the impact in what types of activities we can do. An important part of our program is that we teach the right approach to types of exercise. The approach is more important than the type of exercise because if the approach is wrong you won't get a good response. The approach is known as pacing, but for us it becomes very specific to the patient and is based on the results from the VO2 exercise study. For example, if a patient does an activity that will make them anaerobic as determined by the HR monitor and the parameter set by the exercise study, we would advise work for one minute and rest for 2 minutes. This advice will change from patient to patient.

1. Can you give some examples of good aerobic exercises for relief of CFS symptoms?

Dr. Sol: To start off, lying on your back is the best approach. Not fighting gravity. Yoga on a mat, anything with water, like a pool or ocean, very low impact, and very low heart rate. There is a wide definition of what constitutes relief, it's very subjective, but exercises being tolerated include water-based exercise (for example: water walking, swimming) slow activities with sets made up of no more than 5 repetitions, once a week, yoga (5 poses for 1 minute or less with 2 minutes of rest in between), and other basic exercises. Once you have increased tolerance, you can add in weight training or exercises that utilize body weight. Other kinds of exercise, such as Pilates (if low paced) or resistance exercises using small weights. Keep in mind fatigue can take up to 2 weeks to show up so, every change/addition needs time to play itself out.

2. What symptoms of CFS are improved by aerobic exercise?

Dr. Klimas: We have seen patients be able to make plans without worrying that they will be too tired. They are able to go out, have more endurance during the day, and report an improved quality of life. These are some of the affects that have been seen for those who are good at learning to pace their activities.

Dr. Sol: If I have a patient who can't go out for a walk or swim, I "train" the patient with activities of daily living and help the patient plan so it's possible to accomplish a chosen activity. I ask her what are important days on the calendar so we can plan activities around these events or days so the patient does not have to haphazardly live through these moments. We work with patients with CFS and other fatiguing illnesses to increase the ability to handle the activities of daily living and plan around those activities. By the time the event happens that might cause fatigue, the patient is able to move through it with more tolerance. For some prior athletes, their threshold may be higher because the body remembers. But, if you remember to keep under your threshold, take naps, you can slowly put exercise back into your lives and add more to your of daily living activities.

3. How does this illness affect CFS on a cellular level - mitochondria, ATP, or cytokine productions - in exercise?

Dr. Klimas: Generally, CFS patients are turning things off rather that would normally be turned on in exercise (for example, ATP and cortisol). You should have turned on your cortisol, instead of turned off. You should have turned up ATP production with energy but you've actually down-regulated these cells. Mitochondria are the factories in each cell to produce energy; and we don't know why they are turning things off. They may be protecting the body from triggering other bad outcomes as a result of over-exertion. So, with profound deconditioning across many areas, the mitochondria may shut down because the normal signals asking for more energy are not being produced. Other things can result in deconditioning. For example, astronauts when they return from space and those with MS show deconditioning. The point is to rev back up slowly. We will be doing studies to look at gene expression to see if they are repairing some of the cellular mechanisms. Regarding cytokines – we have patients exercise in little bits below where cytokines get turned on to prevent the inflammatory response and prevent relapse. We're also trying to figure out which cytokines are important so we know how to intervene at a biological level. Staying below your personal threshold for relapse is the key.

4. What dietary measures should we consider? Diet has to play or role or at least be a factor.

Dr. Sol: I recommend patients work with a nutritionist to figure out what nutrients and enzymes are missing to get their body working like normal. This is important for CFS patients because when adrenaline levels are elevated, the gut doesn't work properly because the blood is pulled from the gut to other parts of the body needed for "fight or flight." We need to look at a whole body approach.

Dr. Klimas: I recommend patients try to get most of their nutrients from food, not supplements, since you don't get the trace elements when you just take supplements. A useful website one of my patients found is – you plug in what you eat and the tool tells you what nutrients you didn't get. There are a few supplements we do give to patients:

  • CoQ10 – prevents overworked cells to be damaged further. We use the Ubiquinol form.
  • Vitamin D – it is important to all cells in the body and should be maintained in the high normal range
  • Omega 3 – Helps with inflammation and quiets the cytokines
  • B12 again, maintained in the high normal range
  • Probiotics for GI

5. Should CFS patients get the flu shot?

Dr. Unger: Yes, and we recommend it. But, they should talk to their primary care provider first to ensure there will not be any potential complications.

Dr. Klimas: I agree that CFS patients should get their flu shot, unless they have had a severe relapse with vaccines in the past. Even if it causes a mini-relapse, that's much better than getting the flu and being sick for months. There is also a flu shot available with no preservatives that can be requested.


Autonomic Nervous System: A part of the peripheral nervous system that controls the functions of internal organs and some of the muscles inside the body, such as digestion, respiratory rate, and heart rate.

Parasympathetic/Sympathetic System: the parasympathetic and sympathetic nervous systems are complementary systems that make up the autonomic nervous system; the parasympathetic stimulates activities that occur at rest and the sympathetic stimulates activities associated with the "fight or flight" response.

Dysautonomia: dysfunction of the autonomic nervous system.

Aerobic capacity: the ability to maintain a level of aerobic activity, such as walking, for a particular period of time, which depends on the ability to transport oxygen throughout the body. Beyond the aerobic capacity, the body will switch from using aerobic metabolism to anaerobic metabolism.

Cytokines: protein molecules in the body that play a role in intracellular communication in the immune system.

The notes here are provided as a courtesy to persons who participated in the original call and to other persons using this website. The views expressed in this talk are those of the presenters and do not necessarily represent the opinions of the Centers for Disease Control and Prevention or the U.S. Department of Health and Human Services.

Meeting Agenda
TimeAgenda Details
3:00pmWelcome and Telephone Overview
3:05pmUpdates from CDC - Elizabeth Unger, PhD, MD
Branch Chief, Chronic Viral Diseases Branch
Centers for Disease Control and Prevention
3:15 pm"Redefining Exercise in CFS through Reconstruction of Aerobic Capacity"
Nancy Kilmas, MD
Director, Institute for Neuro-Immune Medicine
Connie Sol, PhDc
Clinical Exercise Physiologist, Institute for Neuro-Immune Medicine
3:45 pmQuestions from CFSPCOCACall Mailbox for Guest Speakers and CDC


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