Fatigue. It is hands down the one single word people most often associate with ME. But should it be? Is it even a defining feature? No!

As with any other neurological illness, people with ME experience a wide range of severe symptoms. These include but are not limited to: severe Central Nervous System damage, brain damage, brain lesions, seizures, paralysis, digestion issues, severe muscle pain (caused in part by a buildup of lactic acid), sleep reversal, insomnia, breathing difficulties, sensitivities to medications, sensitivities to chemicals around us, extreme sensory issues (inability to process light, sound, touch, scent, movement, etc), vision problems, severe cognitive issues (difficulty with or inability to speak or understand speech, or to read, write, problem solve, plan, or even recognize where they are or the loved ones who surround them), etc, etc, etc. For a more complete list of symptoms associated with ME, check out the page ME Symptoms.

So why bring up fatigue at all? I believe this is a crossover from the completely different, but often incorrectly linked, illness Chronic Fatigue Syndrome (see my recent post on this for why and how these diagnoses are not the same). Does fatigue exist in ME? Yes! But not the way most people think. Fatigue in ME isn’t feeling tired after a long day at work. It’s not even feeling tired while battling a cold or flu. Nor is it having sore or painful muscles following exertion. That’s normal. Fatigue in ME is complete and total exhaustion at the cellular level. It affects every part of you, body and mind. A person with ME will actually be weaker and perform worse on successive days of exercise testing – this is something that is present in no other illness (a healthy person’s performance will gradually improve as muscles build and the body becomes more efficient). In addition, one expert I recently read stated that the levels of lactic acid (a pain-inducing chemical produced during exertion) in the average ME patient’s muscles at rest are comparable to an athlete’s levels while running the Boston Marathon. You know that aching pain you sometimes feel in your muscles the day after exercising too hard? That’s us all the time, and worse.

It is important to note that not everyone with ME has fatigue all the time. Most of us do, but it is not a requirement for diagnosis. What happens with ME is that our body is struggling (and failing) to maintain homeostasis even while we rest, so whenever we exert ourselves (physically or mentally) there is a domino effect that leads to profound physical and mental exhaustion. This exhaustion typically has a delayed onset, beginning 24-72 hours after exertion, and may take days, weeks, months, or even years to resolve. Sometimes, if the person is ill enough or the exertion extreme enough, recovery to pre-exertion levels is impossible to ever achieve, and the person is forced to adjust to a new low of “normal” for living.

That said, fatigue alone should never be used as a defining feature of ME. As mentioned above, ME is sooo much more than just fatigue! You wouldn’t define MS, cancer, Lupus, or AIDS by fatigue, and yet all of these conditions cause varying levels of fatigue as well. Just like these illnesses, ME deserves to be known as a larger picture of what it is, not as fatigue alone. The one, core defining feature of ME is damage to the Central Nervous System. It is the key issue behind everything else, the one thing every ME patient must have. It is not fatigue, but it causes fatigue, among many other severe (and sometimes life threatening) symptoms. Let’s spread the message that ME is not fatigue. ME is not feeling tired after exercise. ME is not feeling like staying in bed when you could go out. ME is severe dysregulation of and damage to the Central Nervous System, and it deserves to be recognized as such.