By James Laughlin, PTA
What current research indicates for endurance athletes return to sport
If you are recovering, or have recovered, from COVID-19 you may be wondering when is it appropriate to return to participation in endurance athletic activities? In this brief literature review I hope to outline the current thinking regarding safely returning to endurance activity. Considerations must be given to the body systems affected by COVID-19 and the general health of the athlete prior to infection and post recovery. This review should help you improve your understanding of the risk factors associated with COVID-19 and elicit questions about how best to safely return to endurance physical activity.
COVID-19 is associated with a wide range of dysfunction across many of our bodies systems. Body systems most frequently cited in the literature include cardiac, pulmonary, hematologic, musculoskeletal, and gastrointestinal (1). Significantly the literature states that system involvement is varied and should be addressed on an individual participant basis.
Regarding endurance sport participation three body systems are worth noting. Risk factors associated with the hematologic system include increased risk for hypercoagulability and thrombosis (1). Gastrointestinal system concerns include hydration and energy availability (1). The majority of literature and research has been on the cardiac system.
Early research on the cardiac system looked at cytokine activity and subsequent injury to heart muscle cells (1). Additional complications include arrythmias associated with specific treatments (1). Initial research indicated that a cardiovascular screen should be performed to rule out heart abnormalities associated with COVID-19. This testing would include electrocardiogram (ECG), echocardiogram (EKG) and ultimately cardiac magnetic resonance (CMR) (2). Recent research has indicated that extensive diagnosis with the aforementioned testing may not prove to be efficacious. Primary concerns include over utilization of testing; lack of normative data for comparison; and premorbid, benign abnormalities which can lead to confusion and fear (3, 4).
Current recommendations for return to endurance activity are driven by age, health history prior to infection, intensity of infection, and duration of infection. It is important to reiterate that each individual should be assessed in isolation as everyone’s response is unique. For simplicity we will look at two classes of athletes and current recommendations for return to activity.
One Class of individuals are those previously thought to be healthy, under the age of 35 and who’s symptoms were asymptomatic or minor in intensity. Assuming no symptoms for 14 days, or no symptoms 10 days following a positive test, it is advised that this athlete can return to endurance activity on a modified progression over one month (4). Initial endurance exercise load starts at 50% of previous volume, add 30% week two, 20% week three and finally adding the last 10% in week 4 (1).
Masters athletes, greater than 35 years of age, who pre infection were healthy without comorbidities can also follow the above guidelines assuming that they have been symptom free for fourteen days without a test; or symptoms free ten days following a positive test with no or minor symptoms. Week one load starts at 50% of prior volume. Add 30% week two. Week three add another 20% and finally on week four add final 10% volume (1).
If symptoms persist for greater than fourteen days or of moderate to severe intensity it is best to work with your primary care provider to consider screening and cardiac testing. Suggestions to this group are beyond the scope of this review and require specific advice from your physician
As we continue to see the number of COVID-19 cases rise it is likely that you or someone you know in the athletic community will suffer from this disease. Hopefully this review has consolidated some of the thinking behind COVID-19 and activity restrictions for the endurance athlete.
- Metzl J, McElheny K, et al. Considerations for Return to Exercise Following Mild-to-Moderate COVID-19 in the Recreational Athlete. HSSJ. DOI 10.1007/s11420-020-09777-1
- Udelson J, Curtis M, Rowin E. Return to Play for Athletes After Coronavirus Disease 2019 Infection-Making High-Stakes Recommendations as Data Evolve. JAMA Cardiology. Published online October 26, 2020
- Verwoert G.C., de Vries S.T., et al. Return to sports after COVID-19: a position paper from the Dutch Sports Cardiology Section of the Netherlands Society of Cardiology. Netherland Heart J. Published 13 July, 2020. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7357275/
- Kim J, Levine B, et al. Coronavirus Disease 2019 and the Athletic Heart Emerging Perspectives on Pathology, Risks and Return to Play. JAMA Cardiology. Published online October 26, 2020