Possible benefits of stretching for post-COVID-19

Abstract

Background: COVID-19 is a new disease that causes severe health problems and is responsible for significant complications even after recovery, including disabilities that lead to motor impairment. In this sense, there is currently no protocol for physical exercises for people with physical disabilities caused by the disease. Therefore, it is necessary to find ways for individuals affected by this condition and experiencing motor difficulties to engage in physical activities, preventing their condition from deteriorating further after COVID-19. Objective: To present evidence that stretching improves strength, respiratory and vascular system function, enabling the return of individuals with physical deficits who are hindered from performing activities of daily living. Methods: This study is a literature review that analyzes the correlation between the benefits of active static stretching in individuals with physical disabilities post-COVID-19. The study collected data through accumulated scientific knowledge in the fields of clinical health and physical activity. The literature search was conducted using digital scientific databases, including SciELO, ScienceDirect, Bireme, and Google Scholar. Results: Muscle stretching is a physical activity that has shown promising benefits for post-COVID patients, however, further research in this field is needed. Conclusion: Through the presented studies, it can be concluded that stretching is a type of exercise that potentially can counterbalance various sequels caused by COVID-19, enabling the affected person to return to their daily routines.

Full text

https://doi.org/10.17784/mtprehabjournal.2024.22.1350 MTP&RehabJournal 2024, 22:1350
Manual Therapy, Posturology & Rehabilitation Journal
ISSN: 2236-5435
RESEARCH ARTICLE
Possible benefits of stretching for post-COVID-19
Pablo N. Folha, Reury Bacurau, Marcelo S. Aoki, Marcelo Massa.
School of Arts, Sciences and Humanities of the University of São Paulo (EACH-USP), São
Paulo (SP), Brazil
Abstract
Background: COVID-19 is a new disease that causes severe health problems and is responsible for
significant complications even after recovery, including disabilities that lead to motor impairment.
In this sense, there is currently no protocol for physical exercises for people with physical disabili-
ties caused by the disease. Therefore, it is necessary to find ways for individuals affected by this
condition and experiencing motor difficulties to engage in physical activities, preventing their
condition from deteriorating further after COVID-19. Objective: To present evidence that stretch-
ing improves strength, respiratory and vascular system function, enabling the return of individuals
with physical deficits who are hindered from performing activities of daily living. Methods: This
study is a literature review that analyzes the correlation between the benefits of active static
stretching in individuals with physical disabilities post-COVID-19. The study collected data
through accumulated scientific knowledge in the fields of clinical health and physical activity. The
literature search was conducted using digital scientific databases, including SciELO, ScienceDirect,
Bireme, and Google Scholar. Results: Muscle stretching is a physical activity that has shown
promising benefits for post-COVID patients, however, further research in this field is needed.
Conclusion: Through the presented studies, it can be concluded that stretching is a type of exercise
that potentially can counterbalance various sequels caused by COVID-19, enabling the affected
person to return to their daily routines.
Keywords: Muscle stretching exercise; physical activity; COVID-19.
BACKGROUND
The COVID-19 pandemic, caused by the SARS-CoV-2 virus, emerged in December
2019 in Wuhan, Hubei province, China1. The rapid spread of SARS-CoV-2 led the World
Health Organization (WHO) to proclaim a global pandemic on March 11, 20202.
COVID-19 is characterized as a pathogenesis disease complex and has been a major
public health challenge worldwide1. After remission, apparently healthy individuals
may present various clinical manifestations and peripheral and central inflammatory
responses that generally lead to long-lasting musculoskeletal changes and functional
impairment, characterizing the term "Long COVID"3. Among the symptoms reported in
"Long COVID," an intriguing and increasingly observed manifestation is the persistence
of post-COVID-19 pain, associated with persistent fatigue or mood changes, cognitive
changes, or persistent respiratory disorders4. The Severe Acute Respiratory Syndrome
caused by the coronavirus 2 (SARS-CoV-2) is caused by a virus with high inflammatory
potential 1and is currently known by the name Coronavirus-19 (COVID-19)1-3.
COVID-19 is a disease with multisystemic impairments 1-4 that affects the quality of
life of those affected, both during the presence of the virus and after recovery1-3. Among
all the systems the virus affects, the respiratory (Al-Jahdhami 2022) and cardiovascular3
systems are the most severely impacted, both acutely and chronically1-3. In the
respiratory system, COVID-19 in the early stage causes dyspnea, which can range from
Corresponding author: Pablo
Nascimento Folha
Email: profmspablo@gmail.com
Received: 30 Apr , 2024.
Accepted: 25 Nov, 2024.
Published: 03 Dec, 2024.
Copyright © 2023. This is an Open
Access article distributed under the
terms of the Creative Commons
Attribution Non-Commercial
License which permits unrestricted
non- commercial use, distribution,
and reproduction in any medium
provided article is properly cited
.

Possible benefits of stretching for post-COVID-19 Folha, P.N. et al.
2
mild to severe1. After recovering from COVID-19, the virus can cause some symptoms
that may persist for some time, such as cough, fatigue, and muscle weakness, especially
in the lower limbs. There is a significant possibility of pulmonary fibrosis after treatment
and recovery from the virus5. In the cardiovascular system, the virus causes cellular
damage due to high concentrations of pro-inflammatory cytokines. Moreover, these
cytokines increase thrombotic potential by damaging blood vessels. As a result,
symptoms such as tachycardia and heart palpitations can be observed6,7.
Most patients are discharged from the hospital with stable vital signs at rest;
however, when there is physical exertion beyond rest, they experience difficulties due to
suppressed oxygen saturation, increased heart rate, and low conditioning1. Both
respiratory and cardiovascular system changes after recovering from COVID-19 make it
challenging to perform basic activities of daily life and restrict physical activity due to
systemic physical impairment8,9. The physical activity is crucial for post-COVID-19
recovery, offering significant anti-inflammatory potential by reducing pulmonary
inflammation, restoring endothelial function through nitric oxide release, promoting
vasodilation, and strengthening the immune system1-9. However, as mentioned above,
there is a physical challenge in performing some activities due to physical impairment
resulting from post-COVID-19 sequelae1-10. The difficulties in mobility, such as carrying
equipment or oxygen cylinders, create significant resistance to initiating physical activity
for a substantial portion of those affected, primarily the elderly, sedentary individuals,
and those with chronic illnesses1-9. Despite the challenges in performing physical activity,
it is necessary for improving physical conditioning, which is essential for physical
recovery, an anti-inflammatory response, and the stabilization of vital signs resulting in
short-term improvement in physical conditioning and endurance1. COVID is a known
virus, but the variation 19 represents a new disease in terms of its characteristics10).
Therefore, there is a need for further research on the virus and the development of a
post-COVID-19 training protocol. In this case, it is essential to propose an efficient and
easy-to-administer prescription, involving low-intensity and adaptable physical activity
for the patient. Static stretching is a suitable suggestion for this purpose1. Active static
stretching is an acceptable option under such conditions because it is a straightforward
and easily adaptable physical activity. It is safe, low-intensity, and can be performed
virtually anywhere. This type of physical activity is comprehensive, as it can engage and
work on various muscle groups throughout the body2.
METHODOLOGY
This study can be classified in terms of research type as a literature review, as it
collects data through accumulated scientific knowledge, which encompasses the clinical
health and physical activity field, to analyze a correlation between the benefits of active
static stretching in individuals with physical disabilities after COVID-19. The literature
search was conducted through digital sources of scientific databases, including SciELO,
ScienceDirect, Bireme, and Google Scholar. The literature search was conducted through
digital sources of scientific databases, including SciELO, ScienceDirect, Bireme, and
Google Scholar.

Possible benefits of stretching for post-COVID-19 Folha, P.N. et al.
3
RESULTS AND DISCUSSION
COVID-19 is a new disease that arises from growing studies and requires
multidisciplinary attention, including the field of sports and physical activity. Active
static stretching has been gaining prominence and strength in the scientific community
due to its simplicity, as it is an activity that can be applied at both high and low intensity,
promoting adherence to physical exercise. COVID-19 has a high inflammatory burden,
so we need an activity with a low inflammatory load. When applied at low intensity,
stretching elicits minimal pro-inflammatory response and, in fact, triggers an
anti-inflammatory response11. In addition to its anti-inflammatory effect, stretching also
promotes a positive impact on balance, increasing flexibility and mobility, reducing
stiffness in the ankles, knees, and hips, thus enabling improved mobility12, as
highlighted by Behm and colleagues in 2021, as well as Reddy and Alahmari in 2016
(mobility being one of the challenges faced by COVID-19 patients)13.
Stretching provides a modest improvement in lower limb strength14. Such
improvement may be sufficient for post-COVID-19 individuals to maintain bipedal
stance and mobility alongside the enhanced mobility and balance they will gain.
Stretching also promotes a positive response in oxygen saturation. Saturação is a marker
of blood oxygenation that is affected by the disease, causing negative stability changes,
which can be mitigated by stretching, which has the potential to increase capillary
extensibility, reduce muscular stiffness of the thoracic walls, and improve respiratory
patterns1-15.Another positive aspect of stretching is that this activity not only activates
muscles and tendons but also engages the peripheral nervous system by elongating the
nerves, facilitating nerve communication, thus justifying the improvement in balance
response15.The peripheral circulation is also benefited by stretching. Stretching has the
ability to reduce peripheral capillary tortuosity, facilitating oxygen delivery and
reducing cardiac effort, thus lowering blood pressure16 ,17. The vascular benefit provided
by stretching appears to be more potent than that promoted by walking18. In addition to
stimulating angiogenesis, increasing capillarity, and improving oxygenated blood flow.
In theory, there is a positive response in the major systems affected by COVID-19,
minimizing the impacts of the disease after recovering from COVID-19.
Another study3 highlights the importance of engaging in physical activity for
chronic diseases and underscores its significance. However, when it comes to COVID-19,
there is indeed a shortage of studies with exercise protocols due to this being a new
disease. The same authors3 also emphasize the need for a specific post-COVID-19
exercise protocol, suggesting that it should encompass training for frailty, interstitial
lung disease, heart failure, and pulmonary hypertension. Another study11 mentions that
stretching can be of both low and high intensity, and that high-intensity stretching
releases pro-inflammatory cytokines. In this case, such intensity is not favorable for
post-COVID-19, considering that the virus has a high inflammatory potential. The same
study states that anti-inflammatory activation occurs at low intensity, with low-intensity
stretching being the most suitable for post-COVID-19, considering its low
pro-inflammatory response and its anti-inflammatory activation19. A review study12
from 2020 concludes that stretching has positive effects on balance, both acutely and
chronically, improving the quality of life for individuals with low balance, with a

Possible benefits of stretching for post-COVID-19 Folha, P.N. et al.
4
particular focus on the elderly. It reduces the incidence of falls and enhances flexibility
and mobility. The same study from 2020 also states that the benefits of stretching go
beyond balance, benefiting the cardiovascular system through the reduction of arterial
stiffness, angiogenesis, improved vasodilation, enhanced parasympathetic function, and
reduced chronic stress. These benefits are favorable for post-COVID-19, addressing both
issues related to weakness and balance, as well as the cardiovascular system12.
According to what has been presented in the studies1-18, stretching possesses all the
positive attributes required for initiating physical activity in extreme cases of
post-COVID-19 when physical conditions are limited. The literature provides a wide
range of time protocols for stretching training, which can vary between authors. Another
study20 presents a more comprehensive concept, working with durations of 15s, 60s, 90s,
and 120 seconds. In contrast, a different study21 uses durations of 10s, 20s, 40s, and 60
seconds. employed a protocol with 30 seconds versus a control group. used a protocol of
only 30 seconds22,23. The majority of studies comparing time protocols primarily focus on
analyzing the range of motion as the primary outcome, with some also complementing
their analysis with other variables related to mobility, strength, and balance. As you
mentioned, only a few of the cited authors considered other benefits.
An important point to note is that the 30-second protocol is one of the most
commonly used because it doesn't show significant differences in results when
compared to other protocols in terms of flexibility and is associated with a lower
participant dropout rate. Additionally, it has been shown to contribute to increased
strength, balance, improved oxygen saturation, cardiovascular response, and
vascularization1,17-19. Stretching, due to its simplicity and significance, has been gaining
more and more attention in the literature and can be the most recommended activity to
begin an exercise program. Since there are no specific models, our work has shown
positive benefits in post-COVID-19 recovery. Here's a suggested training protocol1.
Given that, the methodology of our work followed the following protocol: 5
stretching exercises targeting major muscle groups - triceps, shoulder adduction, hip,
hamstring, and quadriceps, with one exercise for each muscle. Each exercise was
performed as follows: 3 sets of 30 seconds of tension, followed by a 30-second rest, and 1
minute for transitioning to the next exercise.
CONCLUSION
We can conclude from the above that active static stretching is potentially the most
suitable physical activity for individuals who have recovered from COVID-19 with
physical impairment, considering its ease of use and safety of application. Despite
COVID-19 being a new area of exploration with no specific protocol in place, stretching
has proven to be effective in cases of physical impairment, potentially improving the
quality of life for those affected. Moreover, as individuals achieve better physical
condition, they can gradually transition to other exercise modalities.
Author Contributions: P.N.F. and R.F.B., conducted the literature review and structured the study.
M.A.S. and M.M., conducted the review and standardization.
Financial Support: The authors declare that there was no financial support.
Conflict of interest: The authors declare no conflict of interest.

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