Chronic Fatigue Syndrome – What Fitness Professionals Need to Know

Tired Client

Because the symptoms of Chronic Fatigue Syndrome, or myalgic encephalomyelitis (ME/CFS), can be exacerbated by exertion, there are key points every fitness professional can keep in mind in order to better serve clients who may be sufferers.

ME/CFS is a serious chronic condition that affects the body systemically (CDC, 2018). Individuals who suffer from this disease face extreme challenges in performing normal everyday activities. Ultimately, their quality of life diminishes as they battle a myriad of symptoms.

Over 800,000 individuals suffer from ME/CFS and about 90 percent have not been diagnosed (IOM, 2015). It’s possible one or more of your fitness clients fit into this category. While it is not within the scope of practice of a fitness professional to diagnose any condition, it is our responsibility to understand special populations and the impact exercise has on certain conditions.

 Woman Waking Up And Yawning

Symptoms of ME/CFS 

Knowing what to look for and what questions to ask about potential symptoms outside of a training session is a great place to start with a client who has been diagnosed. Even without a diagnosis, familiarizing yourself with the following symptoms may alert you to refer your client who may be suffering from ME/CFS:

  • Sleep disturbances. Individuals who experience ME/CFS may not ever feel rested even after a full night of quality sleep.
  • Cognitive processing and memory issues.
  • Orthostatic intolerance. ME/CFS sufferers often experience dizziness, weakness, and lightheadedness that may worsen upon standing or sitting up.
  • Worsening of symptoms after mental or physical activity. This is referred to as post-exertional malaise (PEM).
  • A significant drop in the person’s ability to perform normal activities prior to the illness lasting six months or longer.
  • Extreme fatigue that can be severe, is not a result of unusually difficult activity, is not relieved by sleep or rest, and has not been lifelong.
  • Muscle aches and pains.
  • Tender lymph nodes.
  • Digestive issues.
  • Chills or night sweats.
  • Headaches – new or worsening.

(ACE, 2014; CDC, 2018)

When working with fitness clients, monitoring long-term health is equally as important as the pre-exercise screening process. Continually check in with clients to note any gradual or alarming changes in their health status or anecdotal comments. If you suspect something gravely concerning is occurring, refer the client to his or her primary care provider for further examination.

Difficult to Diagnose

ME/CFS isn’t an obvious condition and is challenging to pinpoint. Doctors must rule out a number of other potential illnesses and causes for the symptoms before a diagnosis can be reached. Consequently, achieving a diagnosis of ME/CFS can be arduous and time-consuming (ACE, 2014; CDC, 2018).

How Exercise Impacts ME/CFS

For those who experience ME/CFS, the symptoms aren’t just obnoxious, they are crippling. Exercise doesn’t seem to be a relief or treatment as was once believed. Previous information about this condition has perpetuated a misconception that exercise is a way out of the confines of ME/CFS (Science Daily, 2017). The disease itself was previously believed to be rooted psychological influences, which has since been discredited (Wessely, David, Butler, & Chalder, 1989; Science Daily, 2017).

In other words, encouraging ME/CFS patients to engage in exercise was believed to be an effective treatment. Research now tells us that is no longer the case. Here’s what you need to know as a fitness professional.

  • More exercise is not better nor does it lessen the impact of the disease.
  • Activity can worsen the symptoms and cause Post-Exertional Malaise (PEM), thus magnifying the fatigue associated with the disease.
  • Exercise should be done in conjunction with doctor’s supervision
  • The goal of any activity should be to improve the quality of life of the ME/CFS individual rather than being performance focused.

(ACE, 2014; Science Daily, 2017).

Because the guidelines previously associated with managing and treating ME/CFS are being updated and new research is being conducted, there are no specific “do this or don’t do that rules” that help fitness professionals or patients with the condition navigate its complexity. As more research is released, this is likely to change.

For now, fitness professionals can work with an ME/CFS patient’s physician to create a balanced plan that doesn’t exacerbate the fatigue or worse the symptoms. Try approaching any activity with a “less is more” perspective.

Here are some ideas to try/suggest:

If symptoms worsen or become exaggerated, clients are encouraged to return to the most recent manageable level of physical activity tolerated (ACE, 2014).

ME/CFS is still a mysterious disease that the medical world has not yet been able to solve or cure. It’s frustrating and debilitating to those who are afflicted by it. Fitness professionals have a responsibility to monitor client progress and determine when a referral is necessary. If you currently have clients suffering from a diagnosed case of ME/CFS, work closely with the client’s physician in order to determine the best course of action.


ACE (2014). ACE Personal Trainer Manual, 5thEdition. San Diego, CA: ACE

University of Florida. (2015, March 12). Why exercise magnifies exhaustion for chronic fatigue syndrome patients. ScienceDaily. Retrieved February 19, 2019 from

Wessely, S., David, A., Butler, S., & Chalder, T. (1989). Management of chronic (post-viral) fatigue syndrome. Journal of the Royal College of General Practitioners.Retrieved February 20, 2019 from  



Dr. Erin Nitschke, NFPT-CPT, NSCA-CPT, ACE Health Coach, Fitness Nutrition Specialist, Therapeutic Exercise Specialist, and Pn1 is a health and human performance college professor, fitness blogger, mother, and passionate fitness professional. She has over 15 years of experience in the fitness industry and college instruction. Erin believes in the power of a holistic approach to healthy living. She loves encouraging her clients and students to develop body harmony by teaching focused skill development and lifestyle balance. Erin is also the Director of Educational Partnerships & Programs for the NFPT. Erin is an editorial author for ACE, IDEA, The Sheridan Press, and the Casper Star Tribune. Visit her personal blog at