Exercise

Physiological effects of exercise
Exercise causes a variety of temporary physiological changes in healthy people.

Immune system
In healthy people, exercise induces a variety of temporary changes to immune markers. Immediately after exercise, natural killer cell activity is decreased and Leukotriene B4 (LTB4) increase, along with the LTB4/PGE2 ratio. Exercise elevates levels of prostaglandin E2 (PGE2) for up to five days.

Neurotransmitters
Acetylcholine, an important neurotransmitter that regulates immune response and muscle strength, decreases during exercise.

Post Exertional Malaise


ME patients who exercise are likely to experience Post-exertional malaise which is a worsening of symptoms following physical, mental, emotional or sensory exertion.

Read the main page: Post-exertional malaise.

Pain threshold
Pain thresholds drop in people with CFS (as per the Fukuda criteria) after graded exercise, whereas in healthy controls, pain thresholds rise. This phenomenon is attributed by the study researchers to a dysfunction of the central anti-nociceptive mechanism in CFS patients.

Microbiome
A small study of ten CFS patients found significant changes in the composition of the microbiome and increased bacterial translocation (movement from the intestine into the bloodstream following exercise. In the blood, the study found increased Clostridium fifteen minutes after exercise and increased Bacilli 48 hours later.

Musculature
Exercise has also been found to induce both early and excessive lactic acid formation in the muscles with reduced intracellular concentrations of ATP and acceleration of glycolysis. Several studies have found abnormal increases in plasma lactate following short period of moderate exercise that cannot be explained by deconditioning.

There is evidence of loss of capacity to recover from acidosis on repeat exercise.

There is evidence of abnormalities of AMPK activation and glucose uptake in cultured skeletal muscle cells in ME/CFS patients.

There is evidence of abnormalities in pH handling by peripheral muscle, and possible evidence of an increased acidosis and lactate accumulation.

Gene expression


There is evidence of increased gene expression following muscular exertion.

A 2011 study found that moderate exercise in CFS increased the expression of 13 genes (sensory, adrenergic and 1 cytokine) for 48 hours, and the increases correlated with fatigue and pain levels. (see graph at right)

Second day exercise test
The seminal study on the response by CFS patients to a 2-day cardiopulmonary exercise test was published by Mark VanNess, Christopher Snell & Staci Stevens in 2007: "Diminished Cardiopulmonary Capacity During Post-Exertional Malaise" A repeat study in 2013 confirmed these results.

In a confirmation study, Doctor Betsy Keller found that patients could not repeat their performance on a second cardiopulmonary exercise test performed a day after the first.

A review by Nijs et al. found that multiple studies showed reduced peak heart rate, reduced endurance, reduced peak work rate, reduced peak oxygen uptake, lower blood lactate values, and an increased respiratory exchange ratio; see 'Oxidative impairment', below.

Read the main page: Two-day cardiopulmonary exercise testing.

Oxidative impairment
DeBecker et al (2000) and VanNess et al (2003) found low VO2 during exercise testing; Fulle et al (2000) demonstrated oxidative damage to DNA. ; and Wong et al (1992) showed defects in oxidative metabolism and poor recovery of ATP after exercise.

Examples of clinical recommendations
While there has been no research on physical therapy alternatives to graded exercise, and many patients find it harmful, many clinicians recommend some exercise or strength training for patients who are able, tending to apply this to non-severely affected patients.

Dr Sarah Myhill
Dr Myhill recommends patients who are well enough engage in strength training, specifically Body by Science created by Dr Doug McGuff and John Little. "If muscle strength is correctly developed, this automatically translates into cardiovascular fitness and increased numbers of mitochondria". Dr Myhill has a page on her web site detailing her recommendations.

Dr. Lucinda Bateman
Dr Bateman encourages her patients to find a way to exercise: "we try to focus on maintaining or improving muscle strength, flexibility and also bit of cardiovascular exercise". She discusses exercise and gene expression in an interview.

Dr. Nancy Klimas
Dr Klimas recommends patients engage in exercise or movement without exceeding a certain heart rate, a proxy for an individual's anaerobic threshold, as established by a VO2 max test. She also recommends alternating periods of exercise and rest. She says that exercise tends to be better tolerated when performed in a horizontal position, like recumbent bicycling or swimming.

Dr. Ritchie Shoemaker
See YouTube video regarding resuming exercise gradually for mold illness aka CIRS patients.

Workwell Foundation
Workwell Foundation, which specialises in two-day cardiopulmonary exercise testing (CPET), recommends short periods (eg: 30 seconds) of analeptic exercise, with periods of rest which are 3-6 times longer than the period of exercise. The amount of exercise that the individual undertakes should be guided by VO2 max testing (or a safe heart rate threshold (generally 60% of maximum heart rate)), and the use of a heart rate monitor (both during exercise and to help with pacing) is recommended to ensure that the individual doesn't exceed their capacity. The Foundation also advises against aerobic exercise for people with ME/CFS.

This approach to exercise differs from Graded Exercise Therapy (GET) in several important ways:
 * There is no claim that the exercise program will cure the condition. The aim is to increase functional strength and flexibility, and to improve quality of life, whilst not exacerbating the condition
 * This program is based on a deep understanding of Post-exertional malaise (PEM), and the importance of staying within the energy envelope in order to not trigger PEM
 * There is a recognition that any approach to exercise with people with ME/CFS must be carefully tailored to the individual. There is no one-size fits all
 * This approach utilises objective measures such as VO2 max testing and heart rate monitoring to guide the level of activity suitable for the individual

United States Centers for Disease Control
The Centers for Disease Control in the United States recommends patients perform strength and conditioning exercise.

UK NICE Guidelines
British blogger, Sally Burch, has written about the The UK National Institute for Health and Care Excellence (NICE) guidelines on maintaining a lower heart rate.

Talks & Interviews

 * 2016, Dr. Mark Van Ness, "Expanding Physical Capability in ME/CFS" Part 1 (of 2) (Mark VanNess)
 * 2016, Dr. Mark Van Ness, "Expanding Physical Capability in ME/CFS" Part 2 (of 2) (Mark VanNess)
 * 2015, 72. Gene-expression and exercise / Gen-expressie en inspanning – dr. Lucinda Bateman (Lucinda Bateman, Science for Patients)
 * 2014, Mark VanNess 'Exercise and ME/CFS' at Bristol Watershed. Part One (Mark VanNess)
 * 2013, CFS gene expression after exercise (part 1) (Lucinda Bateman)
 * 2012, Clinical exercise testing in CFS/ME research and treatment (Christopher Snell)
 * 2012, MECFS Alert Episode 32: Staci Stevens, Director of the Pacific Fatigue Lab (Staci Stevens, ME/CFS Alert)
 * 2012, Top 10 Things You Should Know About Post-Exertional Relapse (Staci Stevens)
 * 2010, Slide presentation to CFSAC (Staci Stevens, CFSAC)
 * 2009, Staci Steven speaking to CFSAC meeting (Staci Stevens)

Studies

 * 2016, Effect of Acute Exercise on Fatigue in People with ME/CFS/SEID: A Meta-analysis
 * 2016, Cochrane meta-analysis
 * 2011, PACE trial

Learn more

 * Oct 2, 2017 - For People With Chronic Fatigue Syndrome, More Exercise Isn't Better - by Michaeleen Doucleff for Shots: Health News From NPR
 * Aug 12, 2016 - Neuromuscular Strain in ME/CFS – Research Study Conclusion in Solve ME/CFS Initiative Newsletter
 * Jul 6, 2016 - Australian metabolomics study of young women with ME/CFS (CCC) by Sasha Nimmo for ME Australia
 * Feb 10, 2016 - Lost in Translation - The ME-Polio Connection and the Dangers of Exercise by Nancy Blake for ProHealth
 * Jan 2016 - Review Article: Understanding Muscle Dysfunction in Chronic Fatigue Syndrome by Gina Rutherford, Philip Manning, and Julia L. Newton
 * Dec 19, 2015 - Exercise alteration of the CFS Microbiome from CFS Remission blog
 * Nov 7, 2015 - Deviant Cellular and Physiological Responses to Exercise in Myalgic Encephalomyelitis and Chronic Fatigue Syndrome by Frank N.M. Twisk, and Keith J. Geraghty
 * Jan 17, 2015 - Dr. VanNess on recent press reports by Sally Burch in Just ME blog
 * 2014 - ME/CFS and Exercise: VO2 Max Testing with Nancy Klimas M.D. - PREVIEW (this is a preview of a pay-per-view video)
 * May 16, 2014 - Sufferers of chronic fatigue, fibromyalgia have hope in new diagnostic tool by Wendy Leonard for Deseret News
 * Autumn 2011 - Loss of capacity to recover from acidosis on repeat exercise in chronic fatigue syndrome: a case–control study, an essay for ME Research UK
 * 2011 - ME/CFS and Exercise: The VO2 Max Based Exercise Program, A Personal View by Dan Moricoli