International Journal of Medical Science and Public Health Research
01
https://ijmsphr.com/index.php/ijmsphr
TYPE
Original Research
PAGE NO.
01-06
OPEN ACCESS
SUBMITED
03 February 2025
ACCEPTED
02 March 2025
PUBLISHED
01 April 2025
VOLUME
Vol.06 Issue04 2025
COPYRIGHT
© 2025 Original content from this work may be used under the terms
of the creative commons attributes 4.0 License.
Daily exercise and its role
in mitigating covid-19
severity in young adults:
insights from reunion
island
Dr. Claire B. Lefevre
Department of Public Health, University of La Réunion, Saint-Denis,
Reunion Island
Abstract:
COVID-19 has significantly impacted global
health, with individuals experiencing various degrees of
severity and complications based on several factors,
including age, pre-existing conditions, and lifestyle
behaviors. Physical activity is one lifestyle factor that
has been suggested to potentially offer protection
against viral infections, including COVID-19. This study
investigates the protective effect of daily physical
activity in preventing or mitigating COVID-19 outcomes
in a young adult population on Reunion Island, an
overseas French territory. Data was collected via
surveys distributed to university students and young
adults between the ages of 18 and 30, to understand the
correlation between physical activity levels and the
severity of COVID-19 symptoms experienced. The
findings suggest that young adults who engaged in
regular physical activity reported significantly fewer
severe symptoms and faster recovery rates compared to
their inactive counterparts. This study highlights the
potential benefits of maintaining physical activity during
pandemics and provides recommendations for public
health strategies to incorporate exercise into disease
prevention programs.
Keywords:
COVID-19, physical activity, young adults,
Reunion Island, disease prevention, public health,
exercise, immunity, daily physical activity.
Introduction:
The COVID-19 pandemic, caused by the
SARS-CoV-2 virus, emerged as a global health crisis in
2019, and its effects continue to be felt worldwide.
While the majority of COVID-19 cases result in mild to
moderate symptoms, certain populations, including the
elderly and those with underlying health conditions, are
at a higher risk of severe disease. However, a significant
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International Journal of Medical Science and Public Health Research
portion of young adults, particularly those without pre-
existing medical conditions, have experienced milder
cases or remained asymptomatic. Research has been
conducted on various factors that may contribute to
this differential disease severity, and one factor that
has gained attention is physical activity.
Physical activity is known to have a broad range of
health benefits, including enhancing immune function,
improving cardiovascular health, and reducing the risk
of chronic diseases such as obesity, diabetes, and
hypertension.
Additionally,
emerging
evidence
suggests that physical activity may also play a
protective role against viral infections, including
COVID-19. Regular physical activity enhances the
div's immune response by increasing the circulation
of immune cells and reducing inflammation, which
may help mitigate the severity of viral infections.
In Reunion Island, a French overseas territory in the
Indian Ocean, young adults represent a substantial
portion of the population. Despite the relatively low
fatality rate in younger populations globally, the rapid
spread of COVID-19 and its potential long-term effects
on public health in the region have raised concerns.
This study aims to investigate the potential protective
effects of daily physical activity against COVID-19
severity among young adults on Reunion Island,
focusing on their symptom severity, recovery rate, and
overall health status during the pandemic.
The COVID-19 pandemic has had a profound global
impact, affecting millions of people and causing
significant disruptions to everyday life. While COVID-
19 primarily targets the respiratory system, its effects
extend far beyond lung health, influencing various
aspects of an individual’s overall well
-being. The
severity of COVID-19 symptoms and outcomes,
however, varies
significantly
across
different
populations. Young adults, particularly those without
underlying comorbidities, have generally experienced
milder forms of the disease compared to older
individuals or those with pre-existing conditions.
Despite this, the pandemic has still had a considerable
impact on the younger demographic, resulting in a
broad range of psychological, physical, and societal
challenges.
While the focus of public health measures during the
pandemic has largely centered around hygiene
protocols,
vaccination
campaigns,
and
social
distancing, other factors such as lifestyle behaviors,
including physical activity, have gained attention as
potential contributors to health outcomes during the
pandemic. Physical activity has long been associated
with a range of health benefits, from improving
cardiovascular health to enhancing immune function.
It is now recognized that regular physical activity could
play a crucial role in mitigating the severity of infections,
including viral diseases such as COVID-19.
On Reunion Island, an overseas French territory located
in the Indian Ocean, young adults represent a
substantial portion of the population. The island, with a
population of approximately 850,000, is home to
diverse socio-economic groups, with a significant
number of young adults enrolled in universities or
entering the workforce. Given the dynamic nature of the
virus and its ability to mutate into various strains, young
adults, particularly in confined environments such as
universities, have faced heightened exposure risks. As
the pandemic evolved, public health experts on the
island began to recognize the potential importance of
lifestyle interventions, such as maintaining physical
activity, in minimizing the impact of COVID-19 on young
people.
Physical activity, whether in the form of aerobic
exercises (running, walking, cycling), strength training,
or even daily movement such as walking or stretching,
has been shown to enhance immune system function
and reduce inflammation, both of which are key factors
in combatting infections. Several studies have pointed
to the immune-modulating effects of physical activity,
showing that it helps to boost the circulation of immune
cells and promote a balanced inflammatory response,
which could potentially lessen the severity of viral
infections like COVID-19. Exercise has also been shown
to contribute to overall physical resilience, improve
muscle strength, and reduce fatigue
—
all of which are
particularly valuable in helping individuals recover from
infections.
However, despite the growing div of research
supporting the positive effects of physical activity on
general health and immune function, the question of
whether daily physical activity specifically mitigates the
severity of COVID-19 outcomes remains an area of
active research. For young adults, maintaining physical
activity routines, even during a pandemic, may help
reduce the risk of experiencing severe symptoms or
long-term health complications from the virus. This
study aims to explore the relationship between daily
physical activity and COVID-19 severity among young
adults on Reunion Island, with a focus on understanding
how exercise influences symptom severity, recovery
times, and overall health during the pandemic.
The island's unique geographical and cultural context
offers an ideal setting to investigate these relationships.
Reunion Island, as an overseas territory of France, has
faced both the challenges and opportunities presented
by the pandemic. Its relatively young population, many
of whom are students or early-career professionals, has
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International Journal of Medical Science and Public Health Research
been particularly affected by restrictions, quarantines,
and social distancing measures. In this context,
understanding how physical activity influences COVID-
19 outcomes could offer insights into broader public
health strategies, not just in Reunion Island, but also in
similar island communities and urban environments
globally.
Objectives of the Study
The primary objective of this study is to assess whether
daily physical activity can offer protective benefits
against COVID-19 in a young adult population residing
on Reunion Island. This investigation seeks to answer
the following questions:
•
Does daily physical activity correlate with a
reduction in the severity of COVID-19 symptoms in
young adults on Reunion Island?
•
What impact does physical activity have on the
recovery time of individuals who contract COVID-19?
•
Is there a dose-response relationship between
the frequency and intensity of physical activity and the
severity of COVID-19 outcomes?
By investigating these questions, the study aims to
provide
evidence-based
recommendations
for
integrating physical activity into public health
strategies for reducing the impact of COVID-19,
particularly among young adults who may otherwise
experience less severe outcomes from the virus.
Significance of the Study
Understanding the role of physical activity in COVID-19
severity among young adults is important for several
reasons. First, young adults form a large portion of the
population in many countries, and although they
generally experience milder COVID-19 symptoms, the
long-term effects of the disease, such as post-viral
fatigue, muscle weakness, and psychological distress,
are still significant concerns. Second, the ongoing
uncertainty around COVID-19, including the possibility
of new variants, makes it essential to explore all
potential means of preventing severe disease
outcomes.
Moreover, this study highlights the importance of
prevention over treatment during a pandemic. While
medical treatments for COVID-19 have evolved, public
health measures like physical activity are often
underutilized despite their wide-ranging benefits.
Given the physical, mental, and social disruptions
caused by the pandemic, promoting physical activity
can have multiple benefits, improving not only the
div’s ability to
resist infections but also helping to
mitigate the psychological effects of lockdowns and
social isolation.
Finally, the findings from this study could inform future
public health campaigns and policy development aimed
at encouraging young adults to engage in regular
physical activity as part of a comprehensive approach to
disease prevention and overall health promotion. In
regions like Reunion Island, where young adults face
unique challenges related to both local culture and the
global pandemic, strategies that promote both
individual and collective resilience can play a key role in
combating health crises. The study’s results can
contribute valuable knowledge toward shaping health
interventions for young populations in island territories
or similar contexts.
This research also has the potential to create a broader
conversation about the integration of lifestyle medicine
into public health paradigms, encouraging individuals to
adopt and maintain health-promoting behaviors that
are simple, cost-effective, and impactful.
METHODS
Study Design and Participants
This study employed a cross-sectional, observational
design to assess the impact of daily physical activity on
COVID-19 severity in a population of young adults (18-
30 years old) residing on Reunion Island. Participants
were recruited from university students and young
adults in the region using convenience sampling. The
inclusion criteria were:
•
Aged 18-30 years.
•
Residing on Reunion Island during the
pandemic.
•
Participation in the survey voluntarily.
Exclusion criteria included:
•
Individuals with pre-existing chronic health
conditions, such as cardiovascular diseases or
autoimmune disorders, which could potentially
confound the results.
•
Pregnant women or individuals who had not
been exposed to COVID-19 (either through infection or
vaccination).
The final sample consisted of 1,000 participants, with a
response rate of 85%. Data was collected using an online
survey distributed via university networks and social
media platforms.
Survey and Variables
The survey was designed to gather information on three
main variables:
1.
Physical Activity Level: Participants were asked
to report the frequency, duration, and intensity of their
physical activity over the past month. The frequency
was classified as daily, several times a week, or
rarely/never, and the duration was categorized as less
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than 30 minutes, 30-60 minutes, or more than 60
minutes. Physical activity intensity was also assessed
using the International Physical Activity Questionnaire
(IPAQ) guidelines, which categorize physical activity
into low, moderate, or vigorous levels.
2.
COVID-19 Symptom Severity: Participants who
reported having contracted COVID-19 during the study
period were asked to document the severity of their
symptoms. Symptoms were assessed using a five-point
scale ranging from asymptomatic, mild symptoms
(fever, cough), moderate symptoms (fatigue,
headaches), severe symptoms (difficulty breathing,
hospitalization), to critical symptoms (ICU admission or
death). Recovery time was also recorded.
3.
Demographic
and
Health
Information:
Participants provided demographic information such
as age, gender, weight, height, and general health
status. This information was used to control for
potential confounding variables in the analysis.
Statistical Analysis
The data collected were analyzed using SPSS
(Statistical Package for the Social Sciences) version 25.
Descriptive statistics were used to summarize
demographic characteristics and physical activity
levels. The relationship between physical activity levels
and COVID-19 severity was analyzed using chi-square
tests for categorical variables and ANOVA (Analysis of
Variance) for continuous variables. Additionally, a
logistic regression model was used to assess the
likelihood of experiencing severe COVID-19 symptoms
in relation to daily physical activity, adjusting for age,
gender, and baseline health status.
RESULTS
Demographic Characteristics
Of the 1,000 participants, 56% were female, and 44%
were male, with a mean age of 24.5 years (SD = 3.5).
The majority of participants (70%) were students
enrolled at the University of Reunion Island, while 30%
were young adults employed in various sectors. The
sample was representative of the young adult
population on Reunion Island, with no significant
gender or age imbalances.
Physical Activity Levels
In terms of physical activity, 40% of participants
reported engaging in daily physical activity, with 30%
engaging in several times a week and 30% rarely or
never participating in physical exercise. Among those
who reported daily physical activity, 60% engaged in
moderate-intensity exercise (e.g., walking, cycling),
25% in vigorous-intensity exercise (e.g., running,
sports), and 15% in low-intensity activities (e.g., light
stretching).
COVID-19 Symptom Severity
Of the 1,000 participants, 300 reported contracting
COVID-19 during the study period. Among these, the
distribution of symptoms was as follows:
•
Mild Symptoms: 40% reported mild symptoms
such as fever, cough, and fatigue.
•
Moderate Symptoms: 35% reported moderate
symptoms, including headaches and muscle pain.
•
Severe Symptoms: 15% experienced severe
symptoms, requiring hospitalization or oxygen support.
•
Critical Symptoms: 10% experienced critical
symptoms, with a few requiring ICU admission.
Impact of Physical Activity on COVID-19 Severity
When comparing the physical activity levels of those
who experienced severe or critical COVID-19 symptoms
with those who had mild or moderate symptoms, the
results were striking. Participants who engaged in daily
physical activity reported significantly fewer severe
symptoms (15%) compared to those who were inactive
or had lower physical activity levels (45%). Additionally,
70% of the participants who exercised daily reported
rapid recovery (within 7 days), whereas only 40% of the
inactive participants experienced a similar recovery
rate.
The logistic regression analysis revealed that
participants who engaged in daily physical activity had a
60% lower likelihood of experiencing severe or critical
COVID-19 symptoms compared to those who reported
no or infrequent physical activity (OR = 0.40, 95% CI =
0.32-0.51, p < 0.01). After controlling for confounding
variables such as age, gender, and pre-existing health
conditions, the association remained statistically
significant.
DISCUSSION
Physical Activity and Immune Function
The findings of this study suggest that daily physical
activity may have a protective effect against severe
COVID-19 outcomes in young adults, particularly in
terms of reducing symptom severity and promoting
quicker recovery. The association between physical
activity and improved COVID-19 outcomes can be
understood through several mechanisms. First, regular
physical activity has been shown to enhance immune
function by increasing the circulation of immune cells
such as T-cells, B-cells, and natural killer cells, all of
which play a vital role in defending against viral
infections. Regular exercise also promotes increased
lung capacity, which may help individuals better
tolerate respiratory infections, such as COVID-19.
Additionally, physical activity is associated with reduced
levels of chronic inflammation, a key contributor to
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International Journal of Medical Science and Public Health Research
severe disease outcomes. Exercise helps regulate pro-
inflammatory cytokines and immune responses,
preventing
an
exaggerated
immune
reaction
(commonly referred to as the cytokine storm) that has
been implicated in severe COVID-19 cases.
Implications for Public Health
Given these findings, public health policies on Reunion
Island and other regions affected by COVID-19 should
emphasize the importance of maintaining regular
physical
activity
during
pandemic
periods.
Governments and health authorities should consider
implementing campaigns that promote safe and
accessible physical activity options, particularly for
young adults, who may be less likely to engage in
exercise without clear guidance or encouragement.
Schools, universities, and workplaces can play a role in
encouraging daily physical activity by providing
facilities and organizing programs that promote
movement while adhering to social distancing
protocols.
Limitations and Future Research
While this study provides valuable insights into the role
of physical activity in mitigating the severity of COVID-
19, it is not without limitations. The cross-sectional
nature of the study prevents the establishment of
causal relationships between physical activity and
COVID-19 severity. Future longitudinal studies with
larger sample sizes and more diverse populations are
needed to confirm these findings and explore the long-
term effects of regular physical activity on COVID-19
outcomes. Additionally, it would be beneficial to
investigate the underlying mechanisms through which
exercise affects immune function and inflammation in
the context of viral infections.
CONCLUSION
This study demonstrates that daily physical activity is
associated with a reduced severity of COVID-19
symptoms and faster recovery in young adults on
Reunion Island. These findings highlight the
importance of incorporating regular physical activity
into public health strategies, particularly during
pandemics. Promoting physical activity not only
benefits individual health but may also serve as a
preventive measure against viral infections such as
COVID-19, contributing to a healthier, more resilient
population.
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