By Dennis Kerrigan, PhD, RCEP, FACSM
As we climb out of the aftermath of the COVID pandemic, we are learning a lot, not just about the disease process, but about how people recover from disease and the importance of regular exercise as part of that journey. Long-COVID (LC), or Post-acute Sequelae of COVID-19, is a syndrome defined as the presence of at least one clinical symptom four or more weeks after SARS-COV-2 infection.1 Often, individuals with LC report myriad symptoms, some of the most common being fatigue, headache, dyspnea and brain fog.2 There also seems to be a constellation of abnormalities related to the autonomic nervous system, known as dysautonomias, that cause orthostatic intolerance (OI).
One type of dysautonomia commonly associated with LC is Postural Orthostatic Tachycardia Syndrome (POTS). It is defined as a clinical syndrome that causes symptoms of OI and tachycardia, specifically orthostatic tachycardia causing the heart rate to rise 30 or more beats from rest without associated hypotension (i.e. drop in systolic and diastolic by 20/10 mm Hg, respectively).3 Another defining clinical criteria for POTS is that symptoms of OI improve when an individual goes from a standing position to a supine one. Interestingly, other common symptoms reported from individuals who suffer from POTS overlap with common LC symptoms (i.e. dyspnea, exercise intolerance, gastrointestinal symptoms, brain fog and headaches).
How Too Much Bed Rest Can Backfire
POTS is not unique to COVID-19; in fact, researchers for years have speculated that one main cause of POTS is a prior viral infection. And while the exact link between the viral infection and autonomic nervous system is not well understood, many individuals who work in cardiac and pulmonary rehabilitation have encountered patients with OI and have likely seen the tangible benefits of exercise firsthand. This is because in addition to some of the speculated causes of POTS, prolonged bed rest and deconditioning seem to play a very important role.
Thinking back to the height of the COVID pandemic, many individuals – even those with mild symptoms – likely experienced extended periods of bed rest and, like many individuals at that time, even after recovery remained at home in a sedentary state. As shown by the classic bedrest studies of the 1960s, prolonged periods of bedrest contribute to a loss in blood plasma, muscle mass and autonomic tone, which in addition to the effects of the virus itself only worsened symptoms such as fatigue and shortness of breath – especially for individuals with existing health conditions.
Cardiopulmonary Rehab an Ideal Setting for Recovery
Because exercise is one of the most effective treatments for POTS, it represents another opportunity for cardiac and pulmonary rehabilitation facilities to show their value.4 One important benefit that these programs provide is monitoring of orthostatic vitals while providing support and reassurance to a patient population that often has trepidation when it comes to exercise. Additionally, the exercise prescription should take into account the severity of the OI and for some patients begin with seated exercises (e.g. recumbent bike and Nustep), while gradually introducing more vigorous and upright modalities. Finally, because of poor muscle tone, it is important to incorporate strength training, particularly of muscles involved in venous return via the skeletal muscle pump (e.g. calf exercises, wall sit, etc.).
Below is an example of an exercise guide that can be used in this population. Providing these patients with an evidence-based exercise regimen such as this and supplementing it with education about fluid intake, proper nutrition and, if applicable, medications, can help reduce symptoms and improve their overall quality of life.
 Jamal SM, Landers DB, Hollenberg SM, Turi ZG, Glotzer TV, Tancredi J, et al. Prospective Evaluation of Autonomic Dysfunction in Post-Acute Sequela of COVID-19. J Am Coll Cardiol. 2022;79:2325-30.
 Goldstein DS. The possible association between COVID-19 and postural tachycardia syndrome. Heart Rhythm. 2021;18:508-9.
 Raj SR, Bourne KM, Stiles LE, Miglis MG, Cortez MM, Miller AJ, et al. Postural orthostatic tachycardia syndrome (POTS): Priorities for POTS care and research from a 2019 National Institutes of Health Expert Consensus Meeting - Part 2. Auton Neurosci. 2021;235:102836.
 Olshansky B, Cannom D, Fedorowski A, Stewart J, Gibbons C, Sutton R, et al. Postural Orthostatic Tachycardia Syndrome (POTS): A critical assessment. Prog Cardiovasc Dis. 2020;63:263-70.
Dr. Kerrigan is a clinical exercise physiologist, researcher and Director of Outpatient Exercise Programs and Weight Management at Henry Ford Hospital's main campus in Detroit, Michigan. He is also a past President of the Clinical Exercise Physiology Association.