Individuals with ME/CFS experience profound exercise intolerance and post-exertionalmalaise. This remote (app-based) pilot study explores whether light, fully self-paced,swimming may be a tolerable form of movement for people with ME/CFS and relatedconditions, due to the distinct physiological effects of water immersion. The horizontalposture and hydrostatic pressure of water supports venous return and reduces orthostaticstress, while cool water exposure may influence autonomic and inflammatory responses. Weare recruiting adults with mild-to-moderate ME/CFS and related conditions for this studyexamining short-term symptom and autonomic responses to gentle swimming. Participantswill choose their own intensity and duration and may stop at any time. A light cyclingsession is available as an optional comparator for those who feel comfortable doing so.[Note: this is not an exercise training or rehabilitation study, and participation isonly intended for individuals who can tolerate some gentle activity and can be in publicspaces without triggering post-exertional malaise. You should be comfortable withswimming, but flotation or other assistive devices are welcome]
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating multisystem
disorder characterized by extreme fatigue, sleep dysfunction, pain, and post-exertional
malaise and/or post-exertional fatigue, and is accompanied by orthostatic intolerance,
and neuroendocrine and immune manifestations. The defining feature of ME/CFS is the
delayed onset (~12-48 h) exacerbation of symptoms following physical, cognitive,
orthostatic, and even emotional exertion, termed post-exertional malaise (PEM). As such,
despite the known benefits of exercise for improving function in most disease states
including other multisystem inflammatory disorders like sepsis, exercising with ME/CFS is
generally contraindicated to avoid a worsening of the condition.
It has been demonstrated that neurovascular dysregulation underlies much of the exercise
intolerance in ME/CFS. When neurovascular function is normalized with pharmacologic
cholinergic stimulation in ME/CFS patients performing upright cycling exercise, cardiac
output, right atrial pressures, and maximal oxygen consumption are improved, possibly
preventing post-exertional malaise. Water immersion can also be used to normalize cardiac
output and right atrial pressures, as the prone/supine postures and hydrostatic pressure
of the water act to passively encourage venous return. Furthermore, the human dive reflex
(when the face is submerged in cool water) increases parasympathetic activation to the
heart, slowing down heart rate. There is also evidence of anti-inflammatory effects of
swimming in patients with cardiovascular, neurological, and rheumatological diseases,
which could also improve inflammation in ME/CFS patients. The purpose of this study is to
determine whether light-to-moderate swimming may be a more tolerable form of movement for
individuals with ME/CFS.
Behavioral: Swimming
Following a week of baseline HRV and symptoms tracking, all participants will be asked to
perform a light swimming session. This session should be at a self-selected intensity and
duration, however it should always be performed at an intensity that is under a rating of
perceived exertion of 5/10 (easy to moderate at most). Recommended duration is ~15-30
min. Participants may use flotation or assistive devices as they wish. Cool water is
recommended.
Behavioral: Cycling
After a minimum of three days of recovery following swimming, and once the visible
application indicates a stable recovery score of at least 4/5 (and the participant feels
okay), they may optionally complete a cycling session on a stationary bike. This biking
session will also be at a self-selected duration and intensity (effort <5/10), which does
not need to match the first session. If participants feel that they are unable to
complete the biking exercise session, they can still participate in the study and only
complete the swimming. If they believe that it would exacerbate symptoms and cause harm,
they should not do the biking.
Inclusion Criteria For ME/CFS participants:
- Be between the ages of 18-80
- Meet the criteria of (ME/CFS). The diagnostic criteria for ME/CFS according to the
primary Canadian Consensus Criteria are: 1. Fatigue (significant physical and mental
fatigue that is new onset, unexplained, persistent or recurrent, and substantially
reduces activity level), 2. Post-exertional malaise and/or post-exertional fatigue
(general feeling of discomfort, weakness and/or fatigue, and potentially worsening
associated symptoms, following physical or mental exertion; slow recovery which is
usually longer than 24 hours), 3. Sleep dysfunction (unrefreshing sleep or
disturbances in sleep quantity or rhythm), and 4. Pain (significant degree of muscle
and/or joint pain, and/or significant headaches of new type, pattern or severity).
This may include individuals with (but not limited to) Post-Viral Fatigue Syndrome,
Long-Covid 19, Overtraining Syndrome (OTS), and/or co-occurring Postural Orthostatic
Tachycardia Syndrome (POTS), Fibromyalgia, and/or Mast Cell Activation Syndrome
(MCAS).
- Experience some degree of post exertional malaise and have some degree of exercise
intolerance upon physical exertion.
- Must have been previously physically active and be able to swim
- Must be considered moderate-to-mild CFS (not severe or very severe) with a FUNCAP27
score between 3.0-5.8.
- Must be able to do some light physical activity and go to public places without
causing post-exertional malaise.
Exclusion Criteria for all participants:
- Individuals with cardiovascular, pulmonary, metabolic, renal, endocrine, autoimmune,
neurological, inflammatory condition, infectious disease, or mental illness that
makes exercise participation a risk will be excluded from the study.
- Individuals who are pregnant will be excluded from the study.
- Individuals with musculoskeletal injuries that prevent exercise participation will
be excluded from the study
Inclusion Criteria for healthy controls:
- Be between the ages of 18-80
- Must be physically active and be able to swim.
Simon Fraser University
Burnaby, British Columbia, Canada
Alexandra Coates, PhD, Principal Investigator
Biomedical Physiology and Kinesiology, Simon Fraser University