Physical Fitness Surveillance and Monitoring Systems Inventory for Children and Adolescents: A Scoping Review with a Global Perspective.

Surveillance of health-related physical fitness can improve decision-making and intervention strategies promoting health for children and adolescents. However, no study has comprehensively analyzed surveillance/monitoring systems for physical fitness globally. This review sought to address this gap by identifying: (1) national-level surveillance/monitoring systems for physical fitness among children and adolescents globally, (2) the main barriers and challenges to implementing surveillance/monitoring systems, and (3) governmental actions related to existing surveillance/monitoring systems. We used a scoping review to search, obtain, group, summarize, and analyze available evidence. Our review involved three stages: (1) identification of surveillance systems through a systematic literature review, with complementary search of the grey literature (e.g., reference lists, Google Scholar, webpages, recommendations), (2) systematic consultation with relevant experts using a Delphi method to confirm/add systems and to gather and analyze information on the barriers and challenges to implementing systems, and (3) Web searches for public documents on government sites and surveillance/monitoring system pages, and direct internet searches to identify relevant governmental actions related to surveillance systems. A total of 15 fitness surveillance/monitoring systems met our inclusion criteria. Experts identified a lack of government support and funding, and the low priority of fitness on the public health agenda as the main barriers/challenges to implementation. Several governmental actions related to surveillance systems were identified, including policies, strategies, programs, and guidelines. We propose a Global Observatory of Physical Fitness to help address these issues.

Intermittent Hypoxic Training Increases and Prolongs Exercise Benefits in Adult Untrained Women.

Alba Camacho-Cardenosa, Marta Camacho-Cardenosa, Johannes Burtscher, Pedro R. Olivares, Guillermo Olcina, and Javier Brazo-Sayavera. Intermittent hypoxic training increases and prolongs exercise benefits in adult untrained women. High Alt Med Biol. 00:00-00, 2024. Background: Exercising in hypoxia may confer multiple health benefits, but the evidence for specific benefits is scarce. Methods: We investigated effects of intermittent hypoxic training (IHT) on the quality of life and functional fitness of healthy adult women, in a double-blind, randomized, placebo-controlled study. Subjects performed 36 sessions of IHT (experimental group, n = 41; fraction of inspired oxygen [FIO2]: 0.17) or the same training in normoxia (control group, n = 41; FIO2: 0.21). Health-related quality of life, fitness tests, and hemoglobin levels were assessed before (T1), directly after (T2), and 4 weeks after (T3) cessation. Results: At T2, upper body strength (+14.96%), lower body strength (+26.20%), and agility (-4.94%) increased significantly in the experimental group compared to baseline but not in controls. The experimental group improved lower body strength more (by 9.85%) than controls at T2 and performed significantly better in walking (by 2.92%) and upper body strength testing (by 16.03%), and agility (by 4.54%) at T3. Perceived general health and vitality was significantly greater in the experimental group at T2 and T3 compared with T1. None of these improvements were observed in the control group. Conclusions: IHT is a promising strategy to induce long-lasting fitness benefits in healthy adult women.

Clustering Health Behaviors in Mexican Adolescents: The HELENA-MEX Study.

Purpose: The prevalence of excess weight within the adolescent population is rapidly increasing in Mexico, especially in areas with lower socioeconomic status. The present study aimed to identify lifestyle clustered patterns in adolescents and analyze the associations among these clusters and body composition. Method: A final sample of n=259 participants (13 to 17 years old, 58.7% girls), residents in rural and urban areas, were included. Hierarchical and k-means clusters analyses included moderate to vigorous physical activity (MVPA), cardiorespiratory fitness (CRF), handgrip strength, screen time, sleep time, and diet. The associations between cluster membership and body composition were analyzed through general linear models (ANCOVA), including sex, age, place of residence, and socioeconomic status as covariates. Results: Three different clusters were identified: Cluster 1, [Unhealthy] (low values in all lifestyle patterns), Cluster 2, [Low Physical Fitness] (low values in CRF and handgrip strength) and Cluster 3, [High Physical Activity and CRF] (highest values in CRF, handgrip strength and MVPA). Clusters 2 and 3 showed high values in screen time and industrialized food consumption. There were no differences in sleep between the 3 Clusters. ANCOVA analysis revealed that participants belonging to Cluster 3 showed significantly lower adiposity and a higher Fat Free Mass compared with the other two clusters (p < 0.05). Conclusion: Our findings suggest that a lifestyle characterized by high levels of physical activity and physical fitness and low consumption of industrialized food may be protective against the problem of obesity, which could be helpful to develop interventions to reduce excess weight in Mexican adolescents.

Health inequalities in Brazilian adolescents: Measuring and mapping gaps in a cross-sectional school-based survey.

Background and Aims: This study aims to describe inequalities in health indicators according to gender, area of residence, and socioeconomic position among Brazilian adolescents. Methods: Cross-sectional study using data from a school-based survey carried out in Brazil in 2019. Twelve health outcomes were evaluated. Dimensions of inequality assessed were gender, area of residence, wealth and subnational region. Results: This study comprises a sample of 124,898 adolescents. The most prevalent outcome was physical inactivity (71.9%) followed by thinking life is worthless (52.6%) and bullying (51.8%). Gender inequalities were more marked for physical inactivity and thinking life is worthless with girls presenting a prevalence more than 20 p.p. higher than boys. In zero-dose HPV, however, the prevalence in girls was 17.7 p.p. lower than in boys. Area of residence and wealth inequalities were smaller than gender disparities. Context presented a relevant role in inequality with analysis stratified by states of the country, revealing high variability in estimates. Conclusions: We highlight the need for attention to disparities between subgroups of the adolescent population, especially for gender inequalities that were the most marked for this age group.

Global prevalence and gender inequalities in at least 60 min of self-reported moderate-to-vigorous physical activity 1 or more days per week: An analysis with 707,616 adolescents.

BACKGROUND: Guidelines recommend that adolescents should accumulate an average of 60 min per day of moderate-to-vigorous physical activity (MVPA). However, using only this cut-off could hide important information. For instance, from a population-level point of view, increasing physical activity for those with no or low physical activity could provide more health benefits than increasing physical activity for those with intermediate levels. Also, including a more sensitive cut-point of ≥1 day per week could be an additional strategy for identifying those with low access/opportunities for physical activity practice. Thus, the current study aims to estimate the prevalence of ≥60 min of MVPA ≥1 days per week among adolescents globally, and to describe any relevant gender inequalities. METHODS: We used representative datasets from 146 countries/territories collected between 2003 and 2019. MVPA was self-reported. Participants were grouped into younger (≤14 years old) and older (>14 years old) adolescents. Crude Poisson regression models were used to identify the relative differences in ≥60 min of MVPA ≥1 days per week between boys and girls, and random-effects meta-analysis models were used to identify the pooled estimates. Analyses were stratified by country and region. RESULTS: Approximately 80% of both younger and older adolescents reported ≥60 min of MVPA ≥1 days per week. This prevalence was ≥94% in Europe and Central Asia and North America, while the estimates for the other regions were <77%. The prevalence of ≥60 min of MVPA ≥1 days per week was higher among boys than girls, with the largest differences occurring among the oldest adolescents (PR≤14y: 1.04 (95% confidence interval (95%CI): 1.03‒1.04) vs. PR>14y: 1.09 (95%CI: 1.08‒1.10)). CONCLUSION: Approximately 8 out of 10 adolescents reported accumulating ≥60 min of MVPA ≥1 day per week, with notable differences between regions. Gender differences were observed in several countries, especially among the oldest adolescents. Priorities for physical activity promotion among adolescents should include increasing access/opportunities for physical activity among those who do not achieve ≥60 min of MVPA ≥1 days per week and reducing gender inequalities.

Are more physical education classes related to less time in leisure-time sedentary behavior? An analysis including adolescents from 73 countries.

This study aimed to verify the association between the weekly frequency of physical education (PE) classes and leisure sitting time among adolescents. We analyzed data from 73 countries using the Global School-based Student Health Survey (283,233 adolescents between 11 and 18 years of age). Leisure sitting time and weekly frequency of PE classes were self-reported. Sex, age, and food insecurity were used as covariates and the analyses were stratified by world regions and country income level. Poisson regression models (random-effects meta-analysis) were used for the main analyses. In comparison with 1 PE class per week (reference group), those with no PE classes presented a lower prevalence of ≥ 3 h/d of leisure sitting time (PR [95%CI] = 0.94 [0.91; 0.98]). On the other hand, adolescents with 2 days (PR [95%CI] = 1.06 [1.02; 1.26]), 3-4 days (PR [95%CI] = 1.17 [1.12; 1.22]), and 5 days (PR [95%CI] = 1.08 [1.04; 1.11]) of PE classes presented a higher likelihood of ≥ 3 h/d of leisure sitting time. No clear differences were observed for the different world regions and country income levels. We conclude that a higher weekly frequency of PE classes is associated with increased leisure sitting time among adolescents worldwide.

Physical Activity and Sitting Time Patterns and Sociodemographic Correlates Among 155,790 South American Adults.

BACKGROUND: To estimate the prevalence of different physical activity (PA) domains and sitting time (ST), and to analyze the association with sociodemographic indicators. METHODS: Data from the most recent nationally representative survey from each of the South American countries, comprising 155,790 adults (18-64 y), were used. Data on leisure-time, transport, and occupational PA (all 3 domains as nonzero), total PA (≥150 min/wk), and ST (≥8 h/d) were assessed by specific questionnaires in each survey. Gender, age group (18-34, 35-49, and 50-64 y), and education (quintiles) were used as sociodemographic factors. Random effect meta-analysis of the association between sociodemographic factors and PA and ST were conducted. RESULTS: The prevalence of PA guidelines compliance and elevated ST in South America was 70.3% and 14.1%, respectively. Women were less likely to achieve the recommended levels of total and domain-based PA. Participants in the highest quintile of education were more likely for elevated ST (2.80, 2.08-3.77), lower occupational PA (0.65, 0.44-0.95), but higher leisure-time PA (3.13, 2.31-4.27), in comparison with lowest quintile. Older adults were less likely to participate in total and leisure-time PA. CONCLUSION: Our findings highlight the urge to tackle the inequalities in PA practice in South America, especially gender and education inequalities, for leisure-time PA.

A Cluster Randomized Controlled Trial of the Archena Infancia Saludable Project on 24-h Movement Behaviors and Adherence to the Mediterranean Diet among Schoolchildren: A Pilot Study Protocol.

Objective: The aim of this paper is to describe the protocol of pilot cluster randomized controlled trial (RCT) that will evaluate the effects of a lifestyle-based intervention. The Archena Infancia Saludable project will have several objectives. The primary objective of this project is to determine the 6-month effects of a lifestyle-based intervention on adherence to 24-h movement behaviors and Mediterranean diet (MedDiet) in schoolchildren. The secondary objective of this project is to test the intervention effects of this lifestyle-based intervention on a relevant set of health-related outcomes (i.e., anthropometric measurements, blood pressure, perceived physical fitness, sleep habits, and academic performance). The tertiary objective is to investigate this intervention's "halo" effect on parents'/guardians' 24-h movement behaviors and adherence to the MedDiet. Methods: The Archena Infancia Saludable trial will be a cluster RCT submitted to the Clinical Trials Registry. The protocol will be developed according to SPIRIT guidelines for RCTs and CONSORT statement extension for cluster RCTs. A total of 153 eligible parents/guardians with schoolchildren aged 6-13 years will be randomized into an intervention group or a control group. This project focuses on two fundamental pillars: 24-h movement behaviors and MedDiet. It will mainly focus on the relationship between parents/guardians and their children. Behavior change strategies for dietary and 24-h movement behaviors in schoolchildren will be based on healthy lifestyle education for parents/guardians through infographics, video recipes, brief video clips, and videos. Conclusions: Most of the current knowledge on 24-h movement behaviors and adherence to the MedDiet is based on cross-sectional or longitudinal cohort studies, warranting a need to design and conduct RCTs to obtain more robust evidence on the effect of a healthy lifestyle program to increase 24-h movement behaviors and to improve adherence to the MedDiet in schoolchildren.

Inequalities in the association between adherence to the Mediterranean diet and physical fitness in the young population during the COVID-19 lockdown / Desigualdades en la asociación entre la adherencia a la dieta mediterránea y la condición física en la población joven durante el confinamiento de la COVID-19

Objective: this study analyzed the association between adherence to the Mediterranean diet and proxy-reported physical fitness among Spanish and Brazilian youths during the COVID-19 lockdown according to several inequality indicators. Methods: we conducted a cross-sectional study with parents and guardians of children and adolescents from Spain and Brazil. The evaluation process was through the use of online questionnaires. Adherence to the Mediterranean diet was assessed using the Mediterranean Diet Quality Index in Children and Adolescents. Proxy-reported physical fitness was determined using the International Fitness Scale. Inequality indicators (gender, nationality, socioeconomic status, and parents/guardians’ education level) were evaluated with a survey completed by the participants’ parents/guardians. Binary logistic regression models estimated the association between adherence to the Mediterranean diet and proxy-reported physical fitness, with stratification according to inequality variables. A total sample of 1,099 Spanish and Brazilian individuals (47.6% girls, aged 3 to 17 years) were included in the analysis. Results: compared to the “improvement needed to Mediterranean diet” category, the “optimal Mediterranean diet” group was significantly associated with “very good” physical fitness in boys (OR = 1.5; 95 % CI: 1.0-2.1) and in participants with parents/legal guardians’ education level without university studies (OR = 1.5; 95 % CI: 1.0-2.4). Conclusions: gender and parents/guardians’ education level plays a significant role in the association between the “optimal Mediterranean Diet” and “very good” physical fitness level in Spanish and Brazilian children and adolescents. Future prospective studies are needed to investigate the role of inequality indicators in this relationship. (AU)

Objetivo: este estudio analizó la asociación entre la adherencia a la dieta mediterránea y la aptitud física autoinformada entre jóvenes españoles y brasileños durante el confinamiento de COVID-19 según varios indicadores de desigualdad. Métodos: se realizó un estudio transversal con padres y tutores de niños y adolescentes de España y Brasil. El proceso de evaluación fue a través del uso de cuestionarios online. La adherencia a la dieta mediterránea se evaluó mediante el Índice de Calidad de la Dieta Mediterránea en Niños y Adolescentes. La aptitud física declarada por los padres se determinó mediante la Escala Internacional de Aptitud Física. Los indicadores de desigualdad (género, nacionalidad, estatus socioeconómico y nivel educativo de los padres/tutores) se evaluaron con una encuesta completada por los padres/tutores de los participantes. Los modelos de regresión logística binaria estimaron la asociación entre la adherencia a la dieta mediterránea y la aptitud física informada por los progenitores, estratificando según las variables de desigualdad. Se incluyó en el análisis una muestra total de 1099 individuos españoles y brasileños (47,6 % niñas, de 3 a 17 años). Resultados: en comparación con la categoría de “necesidad de mejorar la dieta mediterránea”, la de “dieta mediterránea óptima” se asoció significativamente con una aptitud física “muy buena” en los chicos (OR = 1,5; IC del 95 %: 1,0-2,1) y en los participantes con nivel educativo de los padres/tutores sin estudios universitarios (OR = 1,5; IC del 95 %: 1,0-2,4). Conclusiones: el género y el nivel educativo de los padres/tutores legales desempeñan un papel significativo en la asociación entre la “dieta mediterránea óptima” y el nivel de condición física “muy bueno” en niños y adolescentes españoles y brasileños. Se necesitan futuros estudios prospectivos para investigar el papel de los indicadores de desigualdad en esta relación. (AU)

Inequalities in the association between adherence to the Mediterranean diet and physical fitness in the young population during the COVID-19 lockdown.

Introduction: Objective: this study analyzed the association between adherence to the Mediterranean diet and proxy-reported physical fitness among Spanish and Brazilian youths during the COVID-19 lockdown according to several inequality indicators. Methods: we conducted a cross-sectional study with parents and guardians of children and adolescents from Spain and Brazil. The evaluation process was through the use of online questionnaires. Adherence to the Mediterranean diet was assessed using the Mediterranean Diet Quality Index in Children and Adolescents. Proxy-reported physical fitness was determined using the International Fitness Scale. Inequality indicators (gender, nationality, socioeconomic status, and parents/guardians' education level) were evaluated with a survey completed by the participants' parents/guardians. Binary logistic regression models estimated the association between adherence to the Mediterranean diet and proxy-reported physical fitness, with stratification according to inequality variables. A total sample of 1,099 Spanish and Brazilian individuals (47.6% girls, aged 3 to 17 years) were included in the analysis. Results: compared to the "improvement needed to Mediterranean diet" category, the "optimal Mediterranean diet" group was significantly associated with "very good" physical fitness in boys (OR = 1.5; 95 % CI: 1.0-2.1) and in participants with parents/legal guardians' education level without university studies (OR = 1.5; 95 % CI: 1.0-2.4). Conclusions: gender and parents/guardians' education level plays a significant role in the association between the "optimal Mediterranean Diet" and "very good" physical fitness level in Spanish and Brazilian children and adolescents. Future prospective studies are needed to investigate the role of inequality indicators in this relationship.

Introducción: Objetivo: este estudio analizó la asociación entre la adherencia a la dieta mediterránea y la aptitud física autoinformada entre jóvenes españoles y brasileños durante el confinamiento de COVID-19 según varios indicadores de desigualdad. Métodos: se realizó un estudio transversal con padres y tutores de niños y adolescentes de España y Brasil. El proceso de evaluación fue a través del uso de cuestionarios online. La adherencia a la dieta mediterránea se evaluó mediante el Índice de Calidad de la Dieta Mediterránea en Niños y Adolescentes. La aptitud física declarada por los padres se determinó mediante la Escala Internacional de Aptitud Física. Los indicadores de desigualdad (género, nacionalidad, estatus socioeconómico y nivel educativo de los padres/tutores) se evaluaron con una encuesta completada por los padres/tutores de los participantes. Los modelos de regresión logística binaria estimaron la asociación entre la adherencia a la dieta mediterránea y la aptitud física informada por los progenitores, estratificando según las variables de desigualdad. Se incluyó en el análisis una muestra total de 1099 individuos españoles y brasileños (47,6 % niñas, de 3 a 17 años). Resultados: en comparación con la categoría de "necesidad de mejorar la dieta mediterránea", la de "dieta mediterránea óptima" se asoció significativamente con una aptitud física "muy buena" en los chicos (OR = 1,5; IC del 95 %: 1,0-2,1) y en los participantes con nivel educativo de los padres/tutores sin estudios universitarios (OR = 1,5; IC del 95 %: 1,0-2,4). Conclusiones: el género y el nivel educativo de los padres/tutores legales desempeñan un papel significativo en la asociación entre la "dieta mediterránea óptima" y el nivel de condición física "muy bueno" en niños y adolescentes españoles y brasileños. Se necesitan futuros estudios prospectivos para investigar el papel de los indicadores de desigualdad en esta relación.

Adherence to the Mediterranean Diet and Health-Related Quality of Life during the COVID-19 Lockdown: A Cross-Sectional Study including Preschoolers, Children, and Adolescents from Brazil and Spain.

Scientific literature has suggested positive associations between the Mediterranean diet (MD) and the health-related quality of life (HRQoL) in young populations. However, to our knowledge, this relationship is unexplored during a situation of social isolation (i.e., lockdown). The objective of the current study is to examine the relationship between the MD and HRQoL during the COVID-19 lockdown among preschoolers, children, and adolescents from Brazil and Spain. This cross-sectional study includes a sample of 1099 three- to seventeen-year-old participants (47.6% girls) who were recruited via social networks. The HRQoL was assessed with the EQ-5D-Y. The Quality Index for Children and Teenagers (KIDMED) questionnaire was applied to evaluate the relationship between the MD and HRQoL. The highest prevalence of reported problems was found for worried, sad, or unhappy participants (39.8%). Furthermore, the lowest proportion of HRQoL problems was observed for "mobility" (2.5%). The proportion of high adherence to the MD was 44.3%. Participants with greater MD adherence reported higher HRQoL mean scores when compared with those who did not adhere to the MD (83.7 ± 0.6 vs. 85.6 ± 0.7, respectively; p < 0.05). Adherence to the MD and especially daily fruit intake were related to higher HRQoL during the COVID-19 lockdown among Brazilian and Spanish young people aged three to seventeen years.

The genetic predisposition increases the chances of schoolchildren maintaining higher adiposity levels after three years.

BACKGROUND: The behavior of anthropometrics and the relationship with genetic factors through a long-term perspective should be better explored. This study aims to verify the odds of maintaining the nutritional status classification after three years, according to the rs9939609 polymorphism (FTO gene). METHODS: It was a retrospective longitudinal study with 355 schoolchildren (7-17 years). Body mass index, body-fat percentage (BF%), and waist circumference (WC) were measured at baseline and follow-up. The FTO gene was evaluated from blood collection and genotyping performed by real-time polymerase chain reaction. Odds ratios and 95% confidence intervals were calculated. RESULTS: For those homozygous with the A allele, the odds of being at less favorable classification at follow-up were 2.29 (1.24; 4.22) and 4.05 (2.08; 7.86) times higher than expected for BF% and WC, respectively, whereas the odds of being in the more favorable classification at follow-up were 0.34 (0.12; 0.93) and 0.11 (0.01; 0.78) for BF% and WC, respectively. The odds of being at less favorable classification were higher for AA carriers with less favorable classification at baseline for BF% and WC compared to AT and TT carriers. CONCLUSIONS: Schoolchildren with a genetic predisposition to obesity and unfavorable anthropometric profile at baseline had more chances of maintaining their nutritional status after three years of follow-up.

Results From Spain's 2022 Para Report Cards on Physical Activity of Children and Adolescents With Disabilities.

This report aims to provide a better understanding of physical activity (PA) and related factors among Spanish children and adolescents living with disabilities. The 10 indicators used for the Global Matrix on Para Report Cards of children and adolescents living with disabilities were evaluated based on the best available data in Spain. An analysis of strengths, weaknesses, opportunities, and threats based on data provision was drafted by three experts and critically reviewed by the authorship team to provide a national perspective for each evaluated indicator. Government was the indicator with the highest grade (C+), followed by Sedentary Behaviors (C-), School (D), Overall PA (D-), and Community & Environment (F). The remaining indicators received an incomplete grade. There were low levels of PA in Spanish children and adolescents living with disabilities. Yet, opportunities to improve the current surveillance of PA among this population exist.

Results from the Uruguay's 2022 report card on physical activity for children and adolescents.

Background/objective: Uruguay was enrolled in the fourth edition of the Global Matrix on physical activity-related indicators in children and adolescents with the aim of producing its second Report Card and analyses on the ten core indicators. Methods: A harmonized development process proposed by the Active Healthy Kids Global Alliance was followed. The best available scientific and grey literature was systematically searched for all the indicators included in the Report Card (Overall Physical Activity, Organized Sport Participation, Active Play, Active Transportation, Sedentary Behavior, Physical Fitness, Family and Peers, School, Community and Environment, and Government). A grading scale ranging from A to F was used. A new approach was used to grade the Government indicator according to the Active Healthy Kids Global Alliance guidance. Results: New information was identified and 7 out of 10 indicators were graded, while there were 3 out of 10 indicators with incomplete information to be graded. An gender-based analysis was included in this second Report Card, providing separate grades for 5 of the indicators [girls/boys]: Overall Physical Activity [F/F], Organized Sport Participation [F/D], Active Transportation [C/C], Sedentary Behavior [D+/D+], and Community and Environment [D+/C-]. The comparison between 2018 and 2022 analysis showed a decrease in Overall Physical Activity and Organized Sport Participation, while the sources of influence School and Government obtained a higher grade in comparison with the previous Report Card. Conclusion: Uruguay has developed its second version of the Report Card on physical activity-related indicators in children and adolescents. The gender analysis showed inequalities between girls and boys. In summary, behavioral indicators have decreased while sources of influence have risen along the time.

Monitoring Muscle Oxygen Asymmetry as a Strategy to Prevent Injuries in Footballers.

Purpose: It has been hypothesized that sports injury risk is explained by muscle metabolism. The objective was to evaluate the muscle oxygen saturation slopes (ΔSmO2 slopes) and muscle oxygenation asymmetry (MO2Asy) at rest and to study their associations with injuries during the pre-season. Methods: A total of 16 male and 10 female footballers participated in this study. Injuries were diagnosed and classified by level of severity during the pre-season. The workload was also evaluated using the rate of perceived exertion × training time, from which the accumulated loads. The SmO2 was measured at rest in the gastrocnemius muscle using the arterial occlusion method in the dominant and non-dominant legs. The repeated measures ANOVA, relative risk, and binary logistic regression were applied to assess the probability of injury with SmO2 and workload. Results: Higher MO2Asy and ΔSmO2 Slope 2 were found among footballer who suffered high-severity injuries and those who presented no injuries. In addition, an MO2Asy greater than 15% and an increase in accumulated load were variables that explained a greater probability of injury. Conclusion: This study presents the new concept of muscle oxygenation asymmetry in sports science and its possible application in injury prevention through the measurement of SmO2 at rest.

Effects of Moderate-Intensity Training Under Cyclic Hypoxia on Cardiorespiratory Fitness and Hematological Parameters in People Recovered From COVID-19: The AEROBICOVID Study.

BACKGROUND: Recent studies have indicated that people who live at altitude have a lower incidence of coronavirus disease (COVID-19) and lesser severity in infection cases. HYPOTHESIS: Hypoxia exposure could lead to health benefits, and it could be used in the recovery process as an additional stimulus to physical training to improve cardiorespiratory fitness (CRF). STUDY DESIGN: Randomized controlled clinical trial. LEVEL OF EVIDENCE: Level 2. METHODS: The 43 participants, aged 30 to 69 years, were divided into control group (CG, n = 18) and 2 training groups: normoxia (NG, n = 9) and hypoxia (HG, n = 16). Before and after the intervention were evaluated the lactate threshold 2 (L2), peak oxygen uptake (VO2peak), and a blood sample was collected at rest to evaluate hematological adaptation. Both groups performed an 8-week moderate-intensity physical training on a bike. The HG were trained under normobaric hypoxic conditions (fractional inspired oxygen [FiO2] = 13.5%). RESULTS: The 8-week intervention promoted a similar improvement in CRF of people recovered from COVID-19 in the HG (L2 = 34.6%; VO2peak = 16.3%; VO2peak intensity = 24.6%) and NG (L2 = 42.6%; VO2peak = 16.7%; VO2peak intensity = 36.9%). Only the HG presented differences in hematological variables (erythropoietin = 191.7%; reticulocytes = -32.4%; off-score = 28.2%) in comparison with the baseline. CONCLUSION: The results of the present study provide evidence that moderate-intensity training in normoxia or hypoxia promoted similar benefits in CRF of people recovered from COVID-19. Furthermore, the hypoxia offered an additional stimulus to training promoting erythropoietin increase and hematological stimulation. CLINICAL RELEVANCE: The present exercise protocol can be used for the rehabilitation of people recovered from COVID-19, with persistent low CRF. In addition, this is the first study demonstrating that physical training combined with hypoxia, as well as improving CRF, promotes greater hematological stimulation in people recovered from COVID-19.

Surveillance to improve physical activity of children and adolescents.

The global transition to current low levels of habitual physical activity among children and adolescents began in the second half of the last century. Low physical activity harms health in both the short term (during childhood and adolescence) and long term (during adulthood). In turn, low physical activity could limit progress towards several sustainable development goals, undermine noncommunicable disease prevention, delay physical and mental health recovery from the coronavirus disease 2019 pandemic, increase health-care costs and hinder responses to climate change. However, despite the importance of physical activity, public health surveillance among children and adolescents is very limited globally and low levels of physical activity in children is not on the public health agenda in many countries, irrespective of their level of economic development. This article details proposals for improvements in global public health surveillance of physical activity from birth to adolescence based on recent systematic reviews, international collaborations and World Health Organization guidelines and strategies. Empirical examples from several countries illustrate how improved surveillance of physical activity can lead to public health initiatives. Moreover, better surveillance raises awareness of the extent of physical inactivity, thereby making an invisible problem visible, and can lead to greater capacity in physical activity policy and practice. The time has arrived for a step change towards more systematic physical activity surveillance from infancy onwards that could help inform and inspire changes in public health policy and practice globally.

Durant la seconde moitié du siècle dernier, l'activité physique des enfants et adolescents a commencé à baisser à l'échelle mondiale pour atteindre le faible niveau actuel. La sédentarité a des effets néfastes sur la santé, tant à court terme (pendant l'enfance et l'adolescence) qu'à long terme (à l'âge adulte). Elle peut également entraver la progression vers de nombreux objectifs de développement durable, compromettre les efforts de prévention des maladies non transmissibles, retarder la guérison physique et mentale liée à la pandémie de maladie à coronavirus 2019, accroître les dépenses en soins de santé et freiner les réactions au changement climatique. Pourtant, malgré l'importance que revêt l'activité physique, rares sont les dispositifs de surveillance de la santé publique mis en place pour les enfants et adolescents dans le monde. En outre, la lutte contre la sédentarité chez les plus jeunes ne figure pas parmi les priorités de santé publique dans la plupart des pays, quel que soit le niveau de développement économique de ces derniers. Le présent article détaille une série de propositions visant à améliorer la surveillance de la santé publique en matière d'activité physique de la naissance à l'adolescence, fondées sur des revues systématiques récentes, des collaborations internationales ainsi que des stratégies et lignes directrices de l'Organisation mondiale de la Santé. Des exemples empiriques provenant de plusieurs pays illustrent comment cette amélioration peut déboucher sur des initiatives de santé publique. De plus, une meilleure surveillance permet de sensibiliser à l'ampleur de cette inactivité, donnant ainsi de la visibilité à un problème jusqu'alors invisible, et peut renforcer les capacités politiques et pratiques relatives à l'activité physique. Il est temps de procéder à un changement en profondeur afin de surveiller plus systématiquement l'activité physique dès le plus jeune âge, en vue d'orienter et d'encourager l'évolution des politiques et pratiques en la matière dans le monde.

La transición mundial hacia los niveles bajos actuales de actividad física regular entre niños y adolescentes comenzó en la segunda mitad del siglo pasado. La disminución de la actividad física perjudica la salud tanto a corto plazo (durante la infancia y la adolescencia) como a largo plazo (durante la edad adulta). A su vez, la falta de actividad física podría limitar el progreso hacia varios objetivos de desarrollo sostenible, socavar la prevención de enfermedades no transmisibles, retrasar la recuperación de la salud física y mental tras la pandemia de la enfermedad por coronavirus de 2019, aumentar los costes de la atención sanitaria y dificultar las respuestas al cambio climático. No obstante, a pesar de la importancia de la actividad física, la vigilancia de la salud pública entre los niños y los adolescentes es muy limitada a nivel mundial y los niveles bajos de actividad física en los niños no se incluyen en la agenda de salud pública de muchos países, sea cual sea su nivel de desarrollo económico. En este artículo, se detallan propuestas para mejorar la vigilancia de la actividad física en la salud pública a nivel mundial, desde el nacimiento hasta la adolescencia, a partir de recientes revisiones sistemáticas, colaboraciones internacionales y directrices y estrategias de la Organización Mundial de la Salud. Ejemplos empíricos de varios países ilustran cómo una mejor vigilancia de la actividad física puede conducir a iniciativas de salud pública. Asimismo, una mejor vigilancia aumenta la concienciación sobre el alcance de la inactividad física, haciendo evidente un problema poco visible, y puede conducir a una mayor capacidad en la política y la práctica de la actividad física. Ha llegado el momento de dar un paso adelante hacia una vigilancia más sistemática de la actividad física desde la infancia que podría ayudar a informar e inspirar cambios en la política y la práctica de la salud pública en todo el mundo.

Effectiveness, implementation, and monitoring variables of intermittent hypoxic bicycle training in patients recovered from COVID-19: The AEROBICOVID study.

Hypoxic exposure is safely associated with exercise for many pathological conditions, providing additional effects on health outcomes. COVID-19 is a new disease, so the physiological repercussions caused by exercise in affected patients and the safety of exposure to hypoxia in these conditions are still unknown. Due to the effects of the disease on the respiratory system and following the sequence of AEROBICOVID research work, this study aimed to evaluate the effectiveness, tolerance and acute safety of 24 bicycle training sessions performed under intermittent hypoxic conditions through analysis of peripheral oxyhemoglobin saturation (SpO2), heart rate (HR), rate of perceived exertion (RPE), blood lactate concentration ([La-]) and symptoms of acute mountain sickness in patients recovered from COVID-19. Participants were allocated to three training groups: the normoxia group (GN) remained in normoxia (inspired fraction of O2 (FiO2) of ∼20.9%, a city with 526 m altitude) for the entire session; the recovery hypoxia group (GHR) was exposed to hypoxia (FiO2 ∼13.5%, corresponding to 3,000 m altitude) all the time except during the effort; the hypoxia group (GH) trained in hypoxia (FiO2 ∼13.5%) throughout the session. The altitude simulation effectively reduced SpO2 mean with significant differences between groups GN, GHR, and GH, being 96.9(1.6), 95.1(3.1), and 87.7(6.5), respectively. Additionally, the proposed exercise and hypoxic stimulus was well-tolerated, since 93% of participants showed no or moderate acute mountain sickness symptoms; maintained nearly 80% of sets at target heart rate; and most frequently reporting session intensity as an RPE of "3" (moderate). The internal load calculation, analyzed through training impulse (TRIMP), calculated using HR [TRIMPHR = HR * training volume (min)] and RPE [TRIMPRPE = RPE * training volume (min)], showed no significant difference between groups. The current strategy effectively promoted the altitude simulation and monitoring variables, being well-tolerated and safely acute exposure, as the low Lake Louise scores and the stable HR, SpO2, and RPE values showed during the sessions.