Physical Fitness in Young Healthy Adults After COVID-19 Infection
Condition: COVID-19
MeSH terms: COVID-19
Study type: Interventional

Summary: 
      Purpose:

      The aim of this study is to evaluate muscle strength, muscle endurance, flexibility, and
      balance in individuals after mild COVID-19 infection and compare them with healthy
      individuals.

      Methods:

      A total of 118 individuals, 59 individuals between the ages of 18-30 who had COVID-19 (not
      vaccinated) and 59 individuals who did not, will be included in the study. Lower and upper
      extremity muscle strength, flexibility, and static and dynamic balances of the individuals
      will be evaluated and compared with the control group. The descriptive characteristics of the
      individuals will be recorded. The physical activity level of the individuals will be
      determined by the Short Form of International Physical Activity Questionnaire. The strength
      of knee extension and elbow flexion will be evaluated with a dynamometer, and functional
      trunk strength will be evaluated with sit-ups and push-ups tests. Lateral bridge test,
      modified Biering-Sorensen test, trunk flexors endurance test, and prone bridge test will be
      used to evaluate muscle endurance. Participants will perform sit and reach test and back
      scratch test for flexibility. The one-leg stance test and the functional reach test will be
      used to evaluate static and dynamic balance. The level of fatigue experienced by individuals
      during walking and running will score according to the Modified Borg Scale.

      Results:

      The SPSS for Windows 19.0 (IBM SPSS Statistics for Windows, Armonk, NY: IBM Corp.) will be
      used for data analysis. The data will be expressed as mean standard deviation (x±SD) and
      percentage (n%). The homogeneity of the groups will be evaluated with the Levene Test.
      Between groups, muscle strength, flexibility, and balance values will be compared using the
      "Mann Whitney-U" Test. The statistical significance level will be accepted as a p <0.05
      value.

      Conclusion:

      The researchers will discuss the results in light of the recent literature.
    

Detailed description: 
      Introduction Pandemic is the general name given to epidemic diseases that spread and affect
      more than one country in the world. Most recently Coronavirus Disease 2019 (COVID-19) had a
      place among the epidemic diseases (Pollard, 2020). Although COVID-19 is involved in the
      primary respiratory system as acute respiratory distress syndrome, it also affects the
      cardiovascular and neurological systems (Guan,2020). The most common symptoms of COVID-19
      infection are fever, cough, dyspnea, muscle pain, and fatigue. Infection can be seen in all
      age groups, especially in the elderly. The symptoms and course of the disease differ in
      children, young and older adults.

      COVID-19 infection can be categorized clinically as mild, moderate, or severe (critical
      illness). The disease affects 80% of individuals with a mild/moderate clinical condition.
      Patients with mild symptoms and no pneumonia are in this group. Severe illness is seen with
      symptoms such as dyspnea, hypoxia, and affects more than 50% of the lungs in 24-48 hours.
      Approximately 14% of patients are in this group. Critical illness is seen at a rate of 2%.
      Patients should be followed in the intensive care unit because of a severe clinical picture
      such as respiratory failure, shock, and multi-organ failure (Mizumoto,2020).

      Due to its effects on the pulmonary, cardiovascular and neurological systems, COVID-19 causes
      the physical functions of individuals to be adversely affected (Lau, 2005; Fiani, 2020). In
      the peripheral nervous system involvement, there are symptoms such as musculoskeletal pain,
      paresthesia, ataxia, and muscle weakness. In central nervous system involvement, there are
      findings such as headache and vertigo (Stevens, 2007).

      When all these symptoms that occur with COVID-19 infection are combined with the negative
      effects of isolation and inactivity, it has been observed that physical fitness decreases in
      individuals (Pinho,2020).

      In the literature, various studies evaluated physical fitness in middle-aged and elderly
      individuals who have had COVID-19 (Pinho,2020; Rooney 2020). These studies show that aerobic
      endurance and functional capacity of individuals decreased after COVID-19 infection
      (Rooney,2020). Some studies reported there is a decrease in muscle strength (Lee,2020;
      Carfi,2020).

      Individuals may also experience decreased muscle strength, endurance, flexibility, and
      balance skills due to physical inactivity and disease (Pinho,2020; Rooney 2020). A decrease
      in muscle strength and endurance causes difficulty and fatigue in daily activities, decreased
      flexibility leads to musculoskeletal pain and predisposition to injuries, and impaired
      balance leads to loss of skills in daily living activities such as standing, walking, and
      climbing stairs (Pinho,2020; Biddle,2017). There were only a few studies show that isometric
      and concentric muscle strength and performance are negatively affected in individuals
      receiving acute care in the hospital (Carfi,2020; Vaes, 2020; Baririch,2021). Paneroni et al.
      reported that the quadriceps femoris muscle lost 86% and the biceps brachial muscle 73% of
      strength, in individuals aged 40-88 years in acute care (with moderate or severe COVID-19
      infection). The authors compared the muscle strength and exercise tolerance with norm values
      and did not include a healthy control group. Baricich et al., examined the physical
      performance of 204 individuals with a mean age of 57.9 years, who were treated for COVID-19,
      were discharged 3-6 months ago. The authors observed that the balance, lower extremity
      strength, and walking capacity of individuals decreased.

      As can be seen, the negative effects of COVID-19 infection on the pulmonary, cardiovascular,
      and neurological systems and the restriction of physical activity due to the pandemic process
      lead to a decrease in some physical fitness parameters (Franco, 2021). In the literature,
      some studies examined physical fitness parameters such as aerobic capacity and muscular
      strength in middle-aged or elderly patients receiving acute care in hospitals. These studies
      show that the aerobic capacity and muscular strength of individuals with severe exposure
      decrease. However, there are no studies on physical fitness parameters such as muscle
      strength, endurance, flexibility, and balance of young older adults who had mild disease. In
      addition, no comparison was made with a control group consisting of healthy individuals. This
      study aims to evaluate muscle strength, muscle endurance, flexibility, and balance in
      individuals with mild or moderate COVID-19 infection and compare them with healthy
      individuals.

      MATERIALS AND METHODS Study Design The study will conduct on the Baskent University Faculty
      of Health Sciences Physiotherapy and Rehabilitation Department between December 2021 and
      February 2022. Ethics Committee of Baskent University Medicine and Health Sciences Research
      and Non-Interventional Clinical Research approved the study (project no: 21/93). Individuals
      participating in the study read and signed the informed consent form.

      Participants

      Individuals who are a student at Baskent University or working as health personnel at Baskent
      University Hospitals will be included in the study. There are two groups in the study:

      Group 1: Individuals with COVID-19 infection and taking medication with home isolation Group
      2: Healthy individuals without COVID-19 infection (Control group) The sample size was
      calculated with the G Power Version 3.1.9.5 (Universität Kiel, Kiel, Germany) program with
      80% power and 0.05 margin of error, and it was found that a total of 118 individuals, 59
      individuals in each group, should be included in the study.

      Methods The individuals participating in the study will be evaluated with the pandemic rules
      at Baskent University Faculty of Health Sciences and Baskent Hospitals.

      Socio-demographic Variable Descriptive and clinical characteristics of the individuals
      participating in the study such as age, gender, weight, height, occupation, and smoking
      status will be recorded.

      Physical Activity Level IPAQ-SF assesses the physical activity levels of the individuals. The
      short form of the questionnaire consists of seven questions and provides information about
      the time spent sitting, walking, moderately vigorous, and vigorous activities. In scoring,
      below 600 MET-min/week indicates individuals who are not physically active, 600-3000
      MET-min/week values indicate low physical activity levels, and 3000 MET-min/week and above
      values indicate individuals with high physical activity levels. In our study, sedentary
      individuals who receive 600-3000 MET-min/week from the questionnaire will be included
      (Craig,2003; Saglam,2010).

      Evaluation of knee extension and elbow flexion muscle strength The strength of the quadriceps
      femoris and the biceps brachii will be evaluated bilaterally with a muscle strength
      dynamometer (Manual Muscle Tester 01165, Lafayette Instrument, USA). The literature was based
      on the selection of these muscles for evaluation (Paneroni,2021).

      To measure the knee extension strength, the individual brings the knee from 90 degrees
      flexion to full extension in sitting. To standardize the test, the lower extremities will be
      fixed of the chair with a belt, allowing full extension of the knee. Three measurements will
      be performed from the distal tibia with a dynamometer, and the score will be recorded in
      Newtons.

      Elbow flexion will also be measured in a sitting position in a chair. To standardize the
      given resistance, the upper extremity of the individual will be fixed to the arm support of
      the chair, allowing elbow flexion with a belt. During the measurement, the individual will
      try to flex the forearm in supination. Meanwhile, three measurements will be taken from the
      distal forearm with a dynamometer. The average score will be recorded in Newtons.

      Evaluation of functional strength of trunk muscles Sit-ups test: The sit-ups test is a
      measure the endurance of the abdominal and hip-flexor muscles. The physiotherapist will fix
      the feet and ask the individuals to do trunk flexion in the knee flexion position. The number
      of movements performed for 30 seconds will be recorded.(Bliss, 2005, McGill, 2006).

      Push-ups test: The test will be in the prone position, with the hands at shoulder level and
      the elbows flexed, positioned near to the body. Individuals will raise the head, shoulders,
      and trunk from the ground with their elbows in full extension. The test is performed with the
      knees in full extension for men and modified knees in flexion for women. The number of
      movements performed for 30 seconds will be recorded.

      Muscle Endurance Static endurance of trunk muscles is evaluated according to McGill protocol
      (McGill,2006). In the measurements, the test score is recorded time recorded in seconds. The
      researcher stops the test when the individual deteriorates or does not continue.Higher scores
      indicate a good level of endurance.

      Lateral bridge test: Lateral bridge test involves static, isometric contractions of the
      lateral muscles on each side of the trunk that stabilizes the spine.

      Modified "Biering-Sorensen" test: The test measuring how many seconds the individual can keep
      the unsupported upper body (from the upper border of the iliac crest) horizontal, while
      placed prone with the buttocks and legs fixed to the couch by three wide canvas straps and
      the arms folded across the chest.

      Trunk flexors endurance test: Trunk flexion test involving a static, isometric contraction of
      the anterior muscles, stabilizing the spine until the individual exhibits fatigue. The
      researcher stops the test when the individual cannot hold the assumed position.

      Prone bridge test: The prone bridge test measures the muscular endurance of the abdominal
      muscles.

      Flexibility Back scratch test The back-scratch test evaluates upper extremity flexibility.
      The individual will externally rotate one arm over her/his shoulder to reach the lowest point
      on the back with the palm facing the back. The other extremity reaches the highest point on
      the back with the palm facing forward by internal rotation of the other arm. The distance
      between the middle fingers of both hands will be measured with a tape measure. If the middle
      fingers do not touch each other, the distance between them is recorded as a minus value in
      centimeters, if fingers can reach completely, as a zero value, if the fingers cross each
      other, as a positive value in centimeters (Heyward, 2002).

      Sit and reach test Sit and reach test evaluates lower extremity flexibility. In the test, a
      sit and reach board is used. The "0" reference point is taken as the 25 cm inner part where
      the feet are placed on the sit and reach the board. The part closer to the individual from
      the reference point shows negative values, and the part towards the far side shows positive
      values. Individuals will reach as far as with their fingertips by placing their feet on a
      sit-and-reach board. The test is repeated three times. The average score is recorded
      (Heyward, 2002).

      Balance Single leg stance test Individuals bend one knee and place the sole on the other
      thigh and maintain their balance in this position. The test will be performed separately for
      the right and left extremities with eyes open and closed. The test score will recorded as
      seconds (Linda,2013).

      Functional reach test The FRT evaluates dynamic balance and limit of stability. This test
      measures the distance between the length of an outstretched arm in a maximal forward reach
      from standing while maintaining a fixed base of support. The scoring record is centimeter
      (Lin,2012).

      Fatigue Individuals will score perceived fatigue during walking and running activities with
      the Modified Borg Scale. According to the scale, "0" indicates no fatigue, and a score of
      "10" indicates unbearable fatigue (Borg,1987).
    

Intervention name(s): Physical Activity Level; Evaluation of knee extension and elbow flexion muscle strength; Evaluation of functional strength of trunk muscles; Muscle Endurance; Flexibility; Balance; Fatigue
Intervention type(s): Other; Other; Other; Other; Other; Other; Other
Intervention description(s): IPAQ-SF assesses the physical activity levels of the individuals. The short form of the questionnaire consists of seven questions and provides information about the time spent sitting, walking, moderately vigorous, and vigorous activities. In scoring, below 600 MET-min/week indicates individuals who are not physically active, 600-3000 MET-min/week values indicate low physical activity levels, and 3000 MET-min/week and above values indicate individuals with high physical activity levels. In our study, sedentary individuals who receive 600-3000 MET-min/week from the questionnaire will be included; To measure the knee extension strength, the individual brings the knee from 90 degrees flexion to full extension in sitting. To standardize the test, the lower extremities will be fixed of the chair with a belt, allowing full extension of the knee. Three measurements will be performed from the distal tibia with a dynamometer, and the score will be recorded in Newtons.
Elbow flexion will also be measured in a sitting position in a chair. To standardize the given resistance, the upper extremity of the individual will be fixed to the arm support of the chair, allowing elbow flexion with a belt. During the measurement, the individual will try to flex the forearm in supination. Meanwhile, three measurements will be taken from the distal forearm with a dynamometer. The average score will be recorded in Newtons.; Sit-ups test: The sit-ups test is a measure the endurance of the abdominal and hip-flexor muscles. The physiotherapist will fix the feet and ask the individuals to do trunk flexion in the knee flexion position. The number of movements performed for 30 seconds will be recorded.
Push-ups test: The test will be in the prone position, with the hands at shoulder level and the elbows flexed, positioned near to the body. Individuals will raise the head, shoulders, and trunk from the ground with their elbows in full extension. The test is performed with the knees in full extension for men and modified knees in flexion for women. The number of movements performed for 30 seconds will be recorded.; Lateral bridge test: Lateral bridge test involves static, isometric contractions of the lateral muscles on each side of the trunk that stabilizes the spine.
Modified Biering-Sorensen test: The test measuring how many seconds the individual can keep the unsupported upper body horizontal, while placed prone with the buttocks and legs fixed to the couch by three wide canvas straps and the arms folded across the chest.
Trunk flexors endurance test: Trunk flexion test involving a static, isometric contraction of the anterior muscles, stabilizing the spine until the individual exhibits fatigue. The researcher stops the test when the individual cannot hold the assumed position.
Prone bridge test: The prone bridge test measures the muscular endurance of the abdominal muscles.; Back scratch test The back-scratch test evaluates upper extremity flexibility. The individual will externally rotate one arm over her/his shoulder to reach the lowest point on the back with the palm facing the back. The other extremity reaches the highest point on the back with the palm facing forward by internal rotation of the other arm. The distance between the middle fingers of both hands will be measured with a tape measure.
Sit and reach test Sit and reach test evaluates lower extremity flexibility. In the test, a sit and reach board is used. The "0" reference point is taken as the 25 cm inner part where the feet are placed on the sit and reach the board. The part closer to the individual from the reference point shows negative values, and the part towards the far side shows positive values. Individuals will reach as far as with their fingertips by placing their feet on a sit-and-reach board.; Single leg stance test Individuals bend one knee and place the sole on the other thigh and maintain their balance in this position. The test will be performed separately for the right and left extremities with eyes open and closed. The single-leg stance balance time was recorded as seconds (Linda,2013).
Functional reach test The functional reach test evaluates dynamic balance and limit of stability. This test measures the distance between the length of an outstretched arm in a maximal forward reach from standing while maintaining a fixed base of support. The scoring record is centimeter. Higher scores indicate a good level of balance (Lin,2012).; Individuals will score perceived fatigue during walking and running activities with the Modified Borg Scale. According to the scale, "0" indicates no fatigue, and a score of "10" indicates unbearable fatigue (Borg,1987).
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Other
Keywords: COVID-19; Flexibility; Physical Fitness; Muscle strength; postural balance