Evidencing the Influence of the COVID-19 Pandemic and Imposed Lockdown Measures on Fitness Status in Adolescents: A Preliminary Report

Effect of COVID-19 pandemic on bioimpedance health indicators in young adults

OBJECTIVES

Herein, we investigate the relationships between the COVID-19 pandemic and overcoming the virus, and its effects on body composition parameters in young adults from Slovakia.

METHODS

We assessed 773 adults aged 18 to 30 years in pandemic-status sub-groups. Individual lifestyles and overcoming the COVID-19 effects were evaluated by a detailed questionnaire, and body composition parameters were analyzed using the InBody 770 bioimpedance analyzer.

RESULTS

Statistically significant lower values were observed in the male group during the pandemic for the following parameters; proteins and minerals, fat free mass (FFM), skeletal muscle mass (SMM), lean body mass (LBM) and its values in the right and left arm and trunk, total body water (TBW) and its values in the right and left arm and trunk, body cell mass (BCM), basal metabolic rate (BMR) and phase angle (PA). The regression analysis confirmed the negative pandemic effect and the negative impact of COVID-19 on men in the following parameters: proteins (p = .027 for pandemic and p = .005 for COVID-19), FFM (p = .023 for pandemic and p = .005 for COVID-19), LBM (p = .022 for pandemic and p = .004 for COVID-19), SMM (p = .028 for pandemic and p = .005 for COVID-19), TBW (p = .020 for pandemic and p = .004 for COVID-19), BMR (p = .024 for pandemic and p = .005 for COVID-19) and PA (p = .009 for pandemic). Physical activity was a further significant predictor in men for all the above parameters.

CONCLUSIONS

We observed significantly lower body composition parameters associated with fat free mass in young adult men during the pandemic than before it. However, future research is warranted to determine if these effects have long-term significance.

Remote Exercise Training Intervention During the COVID-19 Pandemic: Randomized Controlled Trial

BACKGROUND

Societal measures to contain the spread of COVID-19 (eg, lockdown and contact restrictions) have been associated with decreased health and well-being. A multitude of prepandemic studies identified the beneficial effects of physical exercise on both physical and mental health.

OBJECTIVE

We report on the feasibility of a remote physical exercise intervention and its stress-buffering potential in 2 untrained cohorts: a pre-COVID-19 cohort that completed the intervention in 2019 and a lockdown cohort that started the intervention shortly before pandemic-related restrictions were implemented.

METHODS

In a randomized controlled trial, participants were assigned to either an intervention group (IG; pre-COVID-19 cohort: n=7 and lockdown cohort: n=9) or a control group (CG; pre-COVID-19 cohort: n=6 and lockdown cohort: n=6). IG participants received weekly individualized training recommendations delivered via web-based support. The intervention period was initially planned for 8 weeks, which was adhered to in the pre-COVID-19 cohort (mean 8.3, SD 0.5 weeks) but was extended to an average of 17.7 (SD 2.0) weeks in the lockdown cohort. Participants' health parameters were assessed before and after the intervention: aerobic capacity was measured as peak oxygen uptake (VO2peak) via cardiopulmonary exercise testing. Depressive symptoms were scored via the depression subscale of the Brief Symptom Inventory-18.

RESULTS

Dropout rates were low in both cohorts in the IG (pre-COVID-19 cohort: n=0, 0% and lockdown cohort: n=2, 16.7%) and the CG (pre-COVID-19 cohort: n=0, 0% and lockdown cohort: n=2, 20%). The mean adherence to the training sessions of the IG for both cohorts was 84% (pre-COVID-19 cohort: SD 5.5% and lockdown cohort: SD 11.6%). Aligned rank transform ANOVAs in the lockdown cohort indicated deterioration of VO2peak and depressive symptoms from before to after the intervention in the CG but no longitudinal changes in the IG. Analyses in the pre-COVID-19 cohort revealed significant increases in VO2peak for the IG compared to the CG (P=.04) but no intervention effects on depressive symptoms.

CONCLUSIONS

With low dropout rates and high adherence, the remote intervention was feasible for healthy adults under regular conditions and in the face of pandemic-related stressors. Moreover, our results hint at a stress-buffering effect as well as a buffering of a lockdown-induced deconditioning of remote physical exercise interventions in the pandemic scenario, which can be used in future studies to overcome equally stressful periods of life. However, due to limited statistical power, these findings should be replicated in similar scenarios.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00018078; https://drks.de/search/en/trial/DRKS00018078.

Physical activity levels before and after the COVID-19 restrictions among Danish adolescents: a retrospective cohort study

AIMS

It has been suggested that the COVID-19 restrictions may have negatively impacted physical activity (PA) levels, especially among adolescents, who often use organised sports to support their intrinsic motivation for staying active. This study aimed to investigate whether adolescents were less physically active after the COVID-19 restrictions compared with before and examine whether participation in organised sports has changed since the COVID-19 restrictions.

METHODS

This was a retrospective cohort study of Danish adolescents aged 15 to 19 years. Data was collected using a questionnaire in SurveyXact. The primary variable of interest was moderate or high-intensity PA frequency before and after COVID-19 restrictions (from March 11, 2020, to September 10, 2021). Secondary variables of interest included whether the PA was self-organised (e.g. running, hiking, going to a gym or cycling) or part of an organised sport delivered by a club or other association, before versus after the restrictions.

RESULTS

A total of 324 participants responded to the questionnaire. The relative risk of not performing PA at least twice per week after COVID-19 restrictions compared with before was significantly larger (1.44; 95%CI: 1.19 to 1.85, p = 0.005). Before the lockdowns, 190 (59%) were engaged in organised sports compared with 152 (47%) after the restrictions (relative risk: 1.51, 95%CI: 1.19 to 1.92, p < 0.001).

CONCLUSIONS

Compared with activity levels before the pandemic, adolescents became significantly less physically active following the COVID-19 restrictions, beyond what is typically observed during adolescence. These results emphasise a need for strategies to increase PA levels among adolescents to minimise the long-term negative effects of physical inactivity during adolescence.

Analysis of Changes in Physical Fitness in Children and Adolescents (11-15 Years) From Kraków (Poland) During COVID-19 Pandemic

BACKGROUND

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has posed a threat to society worldwide. The aim of the study was to analyze changes in the physical fitness of 11- to 15-year-olds during the COVID-19 pandemic.

METHODS

Cross-sectional research was conducted in randomly selected schools in Kraków (Poland) during the years 2020 and 2022. The study group included 1635 adolescents aged 11-15 years. The results of fitness tests such as flexibility, standing broad jump, handgrip strength, overhead medicine ball throw, shuttle run (10 × 5 m), and 30-second sit-ups were analyzed. Body height and weight measurements were also taken. The standing broad jump and handgrip strength were normalized. A statistical analysis was performed to compare the differences between groups using 2-way analysis of variance with the Tukey HSD post hoc test or Kruskal-Wallis test.

RESULTS

The test results revealed a deterioration decrease in sit-ups, standing broad jump, shuttle run, and normalized standing broad jump in both sexes. Furthermore, the test results among girls showed a decrease in overhead medicine ball throw and flexibility. An increase in test results of both sexes was noticed in handgrip strength of the right and left hand. Among boys in 2022, the results were better in the flexibility test and overhead medicine ball throw compared with their peers from 2020.

CONCLUSION

This study indicates a decrease in overall physical fitness in adolescents. The observed results may be associated with a decrease in physical activity, changes in nutrition, and restrictions imposed during the COVID-19 pandemic.

Regional differences of physical fitness and overweight and obesity prevalence among college students before and after COVID-19 pandemic since the "double first-class" initiative in China

Introduction

Physical fitness has been widely recognized as a powerful marker of health in children and adolescents, and it negatively affected by the COVID-19 pandemic. The construction of world-class universities and first-class disciplines, known as the "Double First-Class" Initiative (DFC), is a major commitment made by the Chinese government to adapt to changes in the educational environment, both domestically and internationally, in order to promote the development and practice of international higher education. The aim of the study was to look deep into the regional differences of physical fitness and overweight and obesity prevalence among college students before and after the COVID-19 pandemic since the DFC.

Methods

The original physical fitness parameters of students from 10 DFC universities and colleges in Central South China were downloaded from the official website of Chinese National Student Physical Fitness Database (CNSPFD) and then divided into 3 groups based on the pandemic periods: pre-pandemic (2019), the first year after pandemic outbreak (2020), and the second year after pandemic outbreak (2021). All the data were stored in Excel 2010, analyzed by SPSS 17.0, and plotted with ArcGIS 10.4.

Results

The total "fail" percentage (from 9.19% in 2019 to 12.94% in 2021) and the prevalence of overweight and obesity in boys (from 22.53 to 29.25% in 2021) exhibited a continuous increase year by year, and among all the physical fitness indicators the score of strength in boys and endurance quality in all individuals were the lowest in overweight and obesity groups. Students with 'fail' rate developed from northern and northeastern province to southern areas from 2019 to 2021. For grade 2019th, overweight and obesity students who also failed the test had covered nationwide and the most affected areas including northeast, east, as well as central north in senior year. The distribution of overall fitness assessments in Hubei province was in accordance with the national data, and the overall scoring growths in both class of 2021st and 2022nd were measured with a negative increase (p < 0.01).

Conclusion

The government and related functional departments should take into consideration the student regional sources, especially in western and northeast regions of China, and school polices and physical education (PE) teachers should pay more attention to put training efforts on endurance for all adolescents and strength for boys and the group of overweight and obesity who also failed in the standard test, when designing specific interventions to promote physical health and counteract the negative effects of COVID-19 pandemic in college students.

Physical Fitness and Body Mass Index Status of Hong Kong Primary Schoolchildren across the COVID-19 Pandemic, before and after School Closure

OBJECTIVE

To determine whether health-related physical fitness and body mass index (BMI) status differed before and after school closure from the COVID-19 pandemic in a population-based cohort of Hong Kong primary schoolchildren.

STUDY DESIGN

We examined the BMI z score, BMI status, and physical fitness z scores including (i) upper limb muscle strength, (ii) 1-minute sit-up test, (iii) sit-and-reach test, and (iv) endurance run tests, among 3 epochs: prepandemic (September 2018-August 2019), before school closure (September 2019-January 2020), and partial school reopening (September 2021-August 2022), using a repeated cross-sectional approach.

RESULTS

A total of 137 752 primary schoolchildren aged 6-12 years were recruited over 3 academic years. Obesity increased significantly from 25.9% in 2018/19 to 31.0% in 2021/22, while underweight increased slightly from 6.1% to 6.5%. All tested parameters were adversely affected by the pandemic. The negative trend over time was far more pronounced in all 4 physical fitness scores in the underweight group, although performance in handgrip strength had no significance between 2018/19 and 2021/22.

CONCLUSIONS

Schoolchildren who are both underweight and overweight/obese are vulnerable to adverse changes in physical fitness during the COVID-19 pandemic. To eliminate the negative health and fitness outcomes, it is urgent to develop strategies for assisting schoolchildren in achieving a healthy weight, especially in the postpandemic era.

Impact of the COVID-19 lockdown on physical fitness among college women living in China

PURPOSES

The purpose of this study was to evaluate the effects of the COVID-19 lockdown on physical fitness among college women living in China and to explore how fitness changed with different physical conditions.

METHODS

We performed repeated measures of BMI, 800 m running and sit-up performance assessment on college women from one university in China pre and post the COVID-19 lockdown. A total of 3658 (age 19.15 ± 1.08 yr.) college women who completed the same assessment pre and post the COVID-19 lockdown were included in the analysis. We analyzed the data using one way ANOVA and paired-samples t-test.

RESULTS

Due to the COVID-19 lockdown, the result shows a significant increase in BMI by 2.91% (95% CI =0.33, 0.40) and a significant decline in 800 m running and sit-up by 7.97% (95% CI =0.69, 0.77) and 4.91% (95% CI = -0.27, -0.19), respectively. College women in the highest quartile level of physical condition (Quartile 4) had more decreases than college women in the lowest quartile level (Quartile 1). Their BMI level was increased by 3.69% and 0.98% in college women in Quartile 4 and Quartile 1, respectively. Their performance of 800 m running was decreased by 9.32% and 7.37% in college women in Quartile 4 and Quartile 1, respectively. Their performance of sit-up was decreased by 13.88% in college women in Quartile 4 while it increased by 10.91% in college women in Quartile 1, respectively.

CONCLUSIONS

The COVID-19 lockdown might increase the BMI level and decrease 800 m running and sit-up performance among college women living in China. The decrease for college women in higher quartile level of physical condition (Quartile 4) were more seriously while college women in lower quartile level of physical condition (Quartile 1) were modest.

Effectiveness of Physical-Literacy-Based Online Education on Indices of Physical Fitness in High-School Adolescents: Intervention Study during the COVID-19 Pandemic Period

There is a global consensus that physical literacy (PL) is an important determinant of physical fitness (PF), but studies have rarely examined the effects of PL-based interventions on PF. The aim of this research was to evaluate the effectiveness of specific online video-based PL intervention on PF indices in high-school students from Croatia. Participants were 423 high-school adolescents (295 girls, 128 boys; 14-to-18 years of age), divided into an intervention group (n = 230) and a control group (n = 193). The intervention lasted 12 weeks. Educational video materials were disseminated to the intervention group by the closed social network during the pandemic period. Variables included height, mass, BMI, cardiorespiratory fitness (CRF), and power, strength, and flexibility indices. Pre- to post-testing design was applied, with two-way analysis of variance for repeated measurement (Time × Group). Applied intervention induced positive effects in CRF (the intervention group improved their capacities, while no changes occurred in the control group) and BMI (the intervention group retained their BMI levels at the pre-testing level, while BMI of the control group slightly increased over the course of the study), with better effectiveness in girls than in boys. No effects were evidenced for other variables. The positive effects of applied educational intervention on BMI and CRF are encouraging knowing that both indices are related to health status.

Mediating Effects of the COVID-19 Pandemic on the Associations between Physical Activity and Physical Fitness; Cross-Sectional Study among High School Adolescents

The COVID-19 pandemic and the imposed social distancing measures caused negative changes in physical activity levels (PALs) and physical fitness (PF) among adolescents, but the potential mediating effect of the pandemic on the association between PAL and PF is unknown. This study aimed to evaluate gender-specific associations between objectively measured PAL and indices of PF among high school adolescents during the period of the COVID-19 pandemic. The participants were 150 adolescents (101 females) aged 14-18 years; their anthropometrics were evaluated, and they were tested on PF (cardiorespiratory fitness (CRF; beep test), power (broad jump), flexibility (sit-and-reach test), and abdominal strength (sit-ups)) and PAL (using a pedometer for 7 days) during the pandemic period. A T-test was calculated to determine differences between genders. Associations between variables were evaluated using Pearson correlations. Additionally, multivariate taxonomic classification was used to sort participants into homogenous groups (clusters) according to their PF, and then analysis of variance (ANOVA) was performed to differentiate them according to PAL. For the total sample, PAL was correlated with CRF only (R = 0.25, p < 0.05), while gender-stratified correlations showed that PAL was significantly associated with CRF among girls only (R = 0.29, p < 0.05), which was additionally confirmed with multivariate cluster analysis and subsequent ANOVA. No association between PAL and PF was found for boys. The relatively low association between PAL and PF is most likely related to the mediating effect of the change in life circumstances during the COVID-19 pandemic, and limited applicability of pedometers in evaluating high-intensity PAL. Further studies in other age groups and environments are warranted.

Covid Pandemic Effects on the Physical Fitness of Primary School Children: Results of the German EMOTIKON Project

BACKGROUND

In spring of 2020, the Sars-CoV-2 incidence rate increased rapidly in Germany and around the world. Throughout the next 2 years, schools were temporarily closed and social distancing measures were put in place to slow the spread of the Covid-19 virus. Did these social restrictions and temporary school lockdowns affect children's physical fitness? The EMOTIKON project annually tests the physical fitness of all third-graders in the Federal State of Brandenburg, Germany. The tests assess cardiorespiratory endurance (6-min-run test), coordination (star-run test), speed (20-m sprint test), lower (powerLOW, standing long jump test), and upper (powerUP, ball-push test) limbs muscle power, and static balance (one-legged stance test with eyes closed). A total of 125,893 children were tested in the falls from 2016 to 2022. Primary analyses focused on 98,510 keyage third-graders (i.e., school enrollment according to the legal key date, aged 8 to 9 years) from 515 schools. Secondary analyses included 27,383 older-than-keyage third-graders (i.e., OTK, delayed school enrollment or repetition of a grade, aged 9 to 10 years), who have been shown to exhibit lower physical fitness than expected for their age. Linear mixed models fitted pre-pandemic quadratic secular trends, and took into account differences between children and schools.

RESULTS

Third-graders exhibited lower cardiorespiratory endurance, coordination, speed and powerUP in the Covid pandemic cohorts (2020-2022) compared to the pre-pandemic cohorts (2016-2019). Children's powerLOW and static balance were higher in the pandemic cohorts compared to the pre-pandemic cohorts. From 2020 to 2021, coordination, powerLOW and powerUP further declined. Evidence for some post-pandemic physical fitness catch-up was restricted to powerUP. Cohen's |ds| for comparisons of the pandemic cohorts 2020-2022 with pre-pandemic cohorts 2016-2019 ranged from 0.02 for powerLOW to 0.15 for coordination. Within the pandemic cohorts, keyage children exhibited developmental losses ranging from approximately 1 month for speed to 5 months for cardiorespiratory endurance. For powerLOW and static balance, the positive pandemic effects translate to developmental gains of 1 and 7 months, respectively. Pre-pandemic secular trends may account for some of the observed differences between pandemic and pre-pandemic cohorts, especially in powerLOW, powerUP and static balance. The pandemic further increased developmental delays of OTK children in cardiorespiratory endurance, powerUP and balance.

CONCLUSIONS

The Covid-19 pandemic was associated with declines in several physical fitness components in German third-graders. Pandemic effects are still visible in 2022. Health-related interventions should specifically target those physical fitness components that were negatively affected by the pandemic (cardiorespiratory endurance, coordination, speed).

Obesity and weight change during the COVID-19 pandemic in children and adults: A systematic review and meta-analysis

Many obesity risk factors have increased during the COVID-19 pandemic, including physical inactivity, poor diet, stress, and poverty. The aim of this systematic review was to evaluate the impact of the COVID-19 pandemic, as well as associated lockdowns or restrictions, on weight change in children and adults. We searched five databases from January 2020 to November 2021. We included only longitudinal studies with measures from before and during the pandemic that evaluated the change in weight, body mass index (BMI) (or BMI z-scores for children), waist circumference, or the prevalence of obesity. Random effects meta-analyses were conducted to obtain pooled estimates of the mean difference in outcomes. Subgroups were evaluated for age groups and diabetes or obesity at baseline. The risk of bias was assessed using a modified version of the Newcastle-Ottawa Scale, and the certainty of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. A total of 74 studies were included (3,213,776 total participants): 31 studies of children, 41 studies of adults, and 2 studies of children and adults. In children, the pooled mean difference was 1.65 kg (95% confidence interval [CI]: 0.40, 2.90; 9 studies) for weight and 0.13 (95% CI 0.10, 0.17; 20 studies) for BMI z-scores, and the prevalence of obesity increased by 2% (95% CI 1%, 3%; 12 studies). In adults, the pooled mean difference was 0.93 kg (95% CI 0.54, 1.33; 27 studies) for weight and 0.38 kg/m² (95% CI 0.21, 0.55; 25 studies) for BMI, and the prevalence of obesity increased by 1% (95% CI 0%, 3%; 11 studies). In children and adults, the pooled mean difference for waist circumference was 1.03 cm (95% CI -0.08, 2.15; 4 studies). There was considerable heterogeneity observed for all outcomes in both children and adults, and the certainty of evidence assessed using GRADE was very low for all outcomes. During the first year of the COVID-19 pandemic, small but potentially clinically significant increases in weight gain, BMI, and increased prevalence of obesity in both children and adults were observed. Increases were greater in children, and targeted prevention interventions may be warranted.

Effects of High-Intensity Exercise on Physiological Indicators of Recovery Period by Wearing Face Masks of Elite Athletes

Athletes need to maintain the necessary physical conditioning for sports performance while wearing face masks to reduce the risk of virus transmission during training and competition during the COVID-19 situation. The quantitative and physiological effects of face masks on exercise capacity needs to be reported. The purpose of this study was to evaluate elite athletes to quantify, in detail, the effect of a KF94 face mask on changes in lactic acid during recovery after high-intensity aerobic exercise. Thirteen elite soft tennis athletes were recruited. A crossover design was used to examine the effects of using a disposable KF94 face mask compared with not masking during exercise. The participants completed a shuttle run test experiment two times during a 3-day period, including 5−10 min of warmup according to their personal preferences. The lactic acid concentration at 20 min of recovery after maximum exercise was 5.98 ± 1.53 mM/L without a mask and 7.61 ± 1.85 mM/L with a KF94 mask (p < 0.001). The maximum laps of shuttle run tests were 101.5 ± 22.5 laps without a mask and 94.2 ± 20.2 laps with a KF94 mask (p < 0.001). Intense exercise after wearing quarantine masks reduces the maximum aerobic exercise ability and decreases the ability to recover lactic acid.

Changes in Physical Fitness among Elementary and Middle School Students in Korea before and after COVID-19

The present study aimed to analyze changes in health-related physical fitness among Korean elementary and middle school students before (2019) and after (2021) the COVID-19 pandemic. Data collection was completed by requesting the physical activity promotion system (PAPS) data from elementary and middle school students. This information is obtained annually by the Goyang Office of Education in Gyeonggi-do, Korea. The collected data were measured in 2019 and 2021. Data were collected from 17,000 children in the fifth and sixth grades of elementary school and about 24,000 boys and girls in the first, second, and third grades of middle school. Chi-square analyses were used to examine data from each school's health-related physical fitness examinations. Our results indicated that physical fitness levels were significantly lower in 2021 than in 2019 across the following six areas: cardiorespiratory endurance, power, muscular strength, flexibility, obesity, and overall health-related physical fitness (p < 0.05). In addition, the ratio of students with excellent physical fitness (PAPS Grades 1 and 2) significantly decreased from 2019 to 2021, while the ratio of students with poor physical fitness (PAPS Grades 3, 4, and 5) increased (p < 0.05). In addition, there were some differences according to grade and gender. Discussions regarding the impact of decreases in physical activity on physical fitness, interpretations of physical fitness in the context of a pandemic, and practical measures that can be implemented to improve health and fitness among children and adolescents in such situations remain essential.

Trends in Physical Fitness and Nutritional Status among School-Aged Children and Adolescents during the COVID-19 Pandemic in Shaanxi, China-A Cross-Sectional Study

BACKGROUND

This study aimed to explore the characteristics of trends in physical fitness and nutritional status among school-aged students during the COVID-19 pandemic, which could help to develop targeted guidelines and policies for students (adolescents) to promote health during lockdowns resulting from public health emergencies.

METHODS

The physical fitness and nutritional status were measured from 2019 to 2021; the correlation between years and grade were analyzed.

RESULTS

a declining trend was found in aerobic fitness, strength fitness, speed fitness, and BMI during this lockdown.

CONCLUSION

The changes in dietary behavior and the decrease in outdoor physical activities may be the reason for the decline. Furthermore, differences in subjects' growth and limited space at home must be considered in the formulation of exercise and nutritional plans. According to the results of our study, exercise for aerobic fitness should receive more attention when students are enduring a pandemic lockdown. In addition, saying "no" to high-calorie foods in the form of snacking and ultra-processed food was the key to improving subjects' nutritional status.

Physical Fitness of Chinese Primary School Students across the Coronavirus (COVID-19) Outbreak: A Retrospective Repeated Cross-Sectional Study

Social distancing measures against COVID-19 imposed restrictions on students that may have affected their physical health and fitness. The objective of this study was to investigate the change in physical fitness of primary school students across the coronavirus outbreaks from 2019 to 2021. This was a retrospective repeated cross-sectional study. We obtained the annual physical and fitness assessment data measured every November for all students at the same primary school in Guangzhou, China. There was a total of 6371 observations in the dataset for three years. The physical fitness of the students was evaluated with an overall physical fitness score, body mass index (BMI), lung vital capacity, physical flexibility (via a sit-and-reach test) and sports task performances (sprint, shuttle run, rope-jumping, and sit-up). Generalised estimating equations were used to determine any significant changes from 2019 to 2021, adjusted for confounders. After the COVID-19 outbreak in 2021, there was a significant elevation in BMI of 0.64 kg/m2 in 2020 and 0.39 kg/m2 in 2021 (p < 0.001). The overall physical fitness score was significantly increased by 2.1 and 4.1 points, respectively, in 2020 and 2021 (p < 0.001). Lung vital capacity and rope-jumping performance were significantly improved in both 2020 and 2021 compared with 2019, and sit-up performance was marginally significantly improved in 2020 and significantly improved in 2021. However, students demonstrated poorer flexibility and sprint and shuttle run performance in 2021 compared with 2019. A health promotion programme during and after COVID-19, including online physical education classes, television broadcasts, and a rope-jumping campaign, could account for these positive outcomes, along with the ease of administering rope-jumping and sit-ups at home.

Change in BMI and Fitness among Primary School Children in Austria: A 24-Month Follow-Up Study of 303 Children Measured before and during the Ongoing COVID-19 Pandemic

The ongoing COVID-19 pandemic not only impacted the health of school children directly through SARS-CoV-2 infections, but the associated closures of schools and sports facilities also resulted in long-term negative side effects. The aim of this study was to investigate the effects of COVID-19-related mitigation measures on the health and fitness status of primary school children in Austria. A total of 303 primary school children participated in the longitudinal study. Data on height, weight, and fitness were collected before the COVID-19 pandemic (September 2019) and at one-year intervals (September 2020 and September 2021) during the course of the pandemic. In the first year, from September 2019 to September 2020, there were alarming increases in body mass index (BMI) standard deviation scores (SDSs) (from 0.32 to 0.49) and dramatic decreases in both cardiorespiratory endurance (CRE) (from 0.49 to −0.43) and action speed (from −0.31 to −0.64). In the second year (September 2020 to September 2021), the BMI scores stabilized, and improvements in CRE were observed, especially in the subgroup of children who were members of sports clubs. In the future, more initiatives and projects, in addition to sports club activities, should be started and expanded, particularly in schools, to specifically counteract the observed health damage and, thus, have a positive effect on the development of all children, especially those without sports club membership.

To Create a Safe and Healthy Place for Children: The Associations of Green Open Space Characteristics With Children's Use

Green open space (GOS) is an important outdoor resource for the well-being of children by providing places for physical activity (PA), especially in the highly urbanized environment. The COVID-19 lockdowns have made children have more sedentary time than before due to less access to public places. This article aims to examine the associations of GOS characteristics (environmental and surrounding) and children's use (visitation and PA pattern) to provide evidence for promoting their PA during the pandemic. This study employed the method of GPS positioner, accelerometer, and survey to measure the children's actual use in GOS. A total of 179 children participated in the study and 10 GOSs were selected. The children were provided with the accelerometers and GPS positioners to track their walking steps, duration, and locations. The environmental characteristics and 1 km buffer of the selected GOSs were explored as extended study area. Results showed that 49.16% of children reported more visitations than before the pandemic, and 48.60% of them preferred to go on weekdays during the pandemic. Both environmental and surrounding characteristics could affect the visitation pattern. The size (p < 0.000), residential ratio (p < 0.000), and intersection density (p < 0.000) were found as the factors significantly associated with visitation pattern. The children's PA pattern was mainly associated with the environmental characteristics of size (p < 0.000), sports, and playground proportion (p < 0.000). The locations of children's PA were mainly around square, playground, sheltered place, and waterside areas. COVID-19 has transformed the children's use of GOS, as well as their relationship with GOS. The large GOS was more likely to promote PA and its use by the children. The environmental and surrounding characteristics of GOS could affect their use pattern, whereas their PA pattern was mainly associated with the environmental characteristics. The findings suggest that GOS characteristics could be an effective solution to respond the challenge from the pandemic, and promote their visitation and PA.

COVID-19-Related Life Experiences, Outdoor Play, and Long-term Adiposity Changes Among Preschool- and School-Aged Children in Singapore 1 Year After Lockdown

IMPORTANCE

Despite the potential for COVID-19 infection control-related events to have an effect on child well-being, comprehensive assessments of postlockdown changes and persistent outcomes are lacking.

OBJECTIVE

To survey the extent of COVID-19 lockdown-related lifestyle changes, their differences by child age and family socioeconomic status, and the potential association with child adiposity 1 year after lockdown.

DESIGN, SETTING, AND PARTICIPANTS

A self-administered, electronic survey was introduced to 2 ongoing child cohorts (the Singapore Preconception Study of Long-term Maternal and Child Outcomes [S-PRESTO] cohort of preschool children aged 1-4.5 years and the Growing Up in Singapore Towards Healthy Outcomes [GUSTO] cohort of primary school children aged 9-10.7 years) from July 8, 2020, to September 5, 2020, which was 1 to 3 months after the end of strict universal movement restrictions (duration of 73 days ending on June 19, 2020). All active participants from S-PRESTO and GUSTO, 2 population-based, longitudinal, parent-offspring cohorts in Singapore, were invited to participate and monitored through June 15, 2021.

EXPOSURES

Exposures included family income before and after the COVID-19 lockdown, changes in child outdoor play or exercise, and COVID-19-related life events; all data were self-reported by parents and school-aged children 1 to 3 months after the lockdown.

MAIN OUTCOMES AND MEASURES

Primary outcomes were self-reported COVID-19-related life events and changes in child online socialization, outdoor play or exercise, and intrafamily relationships. Study staff measured children's weight, height, and skinfold thickness before and up to 1 year after lockdown. Body mass indices (calculated as weight in kilograms divided by height in meters squared) and World Health Organization-standardized scores were computed. Differences before and after lockdown were compared using baseline-adjusted linear regression.

RESULTS

A total of 604 parents (53% of active cohort participants) and 356 school-aged children completed the survey and were similar to source cohorts. This represents 373 of 761 eligible children in the GUSTO cohort (mean [SD] age, 9.9 [0.4] years; 197 girls [52.8%]) and 231 of 370 eligible children in the S-PRESTO cohort (mean [SD] age, 2.6 [0.8] years; 121 boys [52.6%]). The COVID-19-related life changes were prevalent and varied (eg, 414 of 600 children [69.0%] reported changes in social activities). More than one-third of primary school-aged children (122 of 356 [34.3%]) and one-quarter of preschool-aged children (56 of 229 [24.5%]) eliminated any outdoor play after the lockdown. Lower family income before the lockdown was associated with increased odds of elimination of outdoor play (adjusted odds ratio per 1000 Singapore dollars [$730 US dollars] decrease, 1.09; 95% CI, 1.01-1.19). Complete elimination of outdoor activity (vs continued outdoor activity) was associated with an increase in body mass index of 0.48 (95% CI, 0.03-0.94) and a body mass index z score of 0.18 units (95% CI, 0-0.37) in school-aged children approximately 1 year after lockdown.

CONCLUSIONS AND RELEVANCE

Results of this cohort study suggest that 1 to 3 months after a brief, strict lockdown, a large proportion of parents and school-aged children reported elimination of outdoor play, which was more prevalent in lower-income families. Future research to better understand clinical implications and ways to mitigate lockdown outcomes is essential.

Changes in Physical Fitness during COVID-19 Pandemic Lockdown among Adolescents: A Longitudinal Study

The negative impact of COVID-19 on physical activity has been improved, while the research on changes in physical fitness that may be caused by physical inactivity is still scarce. This study aims to explore the impact of the COVID-19 pandemic lockdown on physical fitness, and the impact of initial physical fitness indicators on their changes during the lockdown in adolescents. A longitudinal study including 265 adolescents aged 14.1 ± 0.4 years old was conducted in China. Physical fitness measurement at baseline and follow-up were respectively measured before (November 2019) and after the lockdown (July 2020). Several physical fitness indicators including aerobic fitness (i.e., 800-m or 1000-m run) and explosive force (i.e., 50-m sprint) deteriorated during the lockdown. Whereas the performances of vital capacity, flexibility (i.e., sit and reach), and muscular strength (i.e., pull-ups) were significantly improved during the lockdown. Furthermore, the reduction in physical fitness for adolescents with higher physical fitness before the lockdown was greater than that for others. These findings may contribute to the development of targeted intervention strategies for physical fitness promotion during the lockdown caused by the public health emergency.

Change in physical fitness due to the COVID-19 pandemic lockdown in French adolescents: a comparison between two independent large samples from Diagnoform battery

Numerous studies reported a significant decline in physical activity level in adolescents as a result of the COVID-19 lockdown. Physical fitness is recognized as a powerful marker of health in youth. The aim of this study was to evaluate the impact of the COVID-19 pandemic lockdown on health-related physical fitness in French adolescents. Two cross-sectional studies were performed comparing two different groups of French adolescents, before (sample 1) and after the first lockdown (sample 2). A total of 1231 adolescents (aged to 16.5 ± 1.5 years) participated in the two cross-sectional studies. Complete data for physical fitness and anthropometrics data were obtained. Adolescents from sample 2 showed lower physical fitness levels compared to adolescents from sample 1. Regarding physical fitness for boys and girls, physical fitness levels were significantly lower in both sex between adolescents from the sample 1 and adolescents from the sample 2, except for cardiorespiratory fitness and flexibility for boys and girls, respectively. The physical fitness global score was also significantly lower between adolescents from the sample 1 and 2 for boys (-9.8%, p < 0.01) and girls (-16.2%; p < 0.01), respectively. Overall, the higher difference was found for performance in the speed body displacement test (-30%). A difference of 12.8% and 25% was observed for boys and girls, respectively.   Conclusion: COVID-19 pandemic lockdown had a negative impact on physical fitness in French youth. This study highlights the need to develop, in a near future, prevention programmes in order to improve the physical fitness in youth. What is Known: • COVID-19 pandemic deeply impacted lifestyle habits. A worrying decrease of physical activity, associated to a dramatic increase of time spent in sedentary behaviors was found in many coutries. What is New: • Our study bring first data on the health-related physical fitness consequences due to lockdown in French adolescents. Our study demonstrate the negative impact of COVID-19 pandemic lockdown on health-related physical fitness in French adolescents.

The Effects of a Five-Month Lockdown Due to COVID-19 on Physical Fitness Parameters in Adolescent Students: A Comparison between Cohorts

Background: This study examined the effects of a five-month lockdown due to COVID-19 pandemic on physical fitness parameters in urban adolescent male and female students. Methods: Two hundred and ninety-three male and female students (age: 15.8 ± 0.3 years) who attended the fourth grade of the same high school during the years 2016–2017 (first control group), 2018–2019 (second control group) and 2020–2021 (lockdown group) took part in the present study. Results: The percentage of overweight and obese students, according to body mass index, increased in males from 16.0% (2016–2017) and 14.6% (2018–2019), to 36.7% in 2020–2021 (p < 0.01), and in females from 8.6% (2016–2017) and 7.0% (2016–2017), to 25.6% in 2020–2021 (p < 0.01). Lower body fitness, as assessed by jumping, sprinting and agility tests, was impaired for both males and females after the lockdown compared with the 2016–2017 and 2018–2019 cohorts (vertical jumps: 10.4–15.1%; p < 0.01; d = 0.58–1.01, 30 m sprint: 3.7–4.9%; p < 0.01; d = 0.62–0.74; 505 agility test: from 6.1% to 9.4%; p < 0.01; d = 0.80–1.04). However, flexibility and performance in upper-body fitness tests (handgrip maximum isometric strength and medicine ball throws with different loads) was significantly reduced only in males after the lockdown (p < 0.05 to 0.01). Conclusions: These results suggest that a five-month lockdown negative influenced the physical fitness of adolescent students. Notably, greater reductions were observed in upper body strength, power and flexibility in males than in females. These results highlight the need to maintain strength, power and body mass during long periods of inactivity in adolescent populations.