Fitness and fatness in children and adolescents: investigating their role in the association between physical activity and cardiometabolic health.

To verify the role of the combination of fitness and fatness in the relationship between physical activity (PA) and cardiometabolic risk in children and adolescents. This is a cross-sectional study performed with 2786 children and adolescents (6 to 17 years). Fitness was determined by the cardiorespiratory fitness (CRF) six-minute walking and running test. Waist circumference (WC) was considered a fatness indicator. A selfreported questionnaire was used to determine PA practice, whereas the clustered cardiometabolic risk score (cMetS) was calculated by summing z-scores of triglycerides, total cholesterol/HDL-C ratio, systolic blood pressure, glucose, and WC. Considering the combination of CRF (fitness) and WC (fatness), the following phenotypes were created: Fit/Unfat, Fit/Fat, Unfit/Unfat and Unfit/Fat. Moderation analyses were tested using linear regression models. Significant interactions were found between PA and Unfit/Fat category (ß = -0.001; p = 0.001) only for adolescents. The interaction observed in the Unfit/Fat phenotype indicated that adolescents who practise PA for 330 minutes per week presented lower cMetS compared to those who do not practise or practise for 60 minutes respectively. The combination of fitness and fatness moderates the relationship between PA and cardiometabolic risk, suggesting that adolescents, particularly those who are less fit and present high adiposity, should be encouraged to engage in regular PA to improve their metabolic health.

Validity, Reliability, and Sensitivity of Mobile Applications to Assess Change of Direction Speed.

This study aimed to assess the validity, reliability, and sensitivity of mobile applications for assessing change-of-direction speed (CODS) performance. Thirty college athletes performed two Illinois CODS tests during one session. Assessments were carried out simultaneously using six devices (the CODTimer app, Seconds Count app, StopwatchCamera app, two analog stopwatches, and timing gates). Validity analyses included Pearson's product-moment correlation analysis, a linear regression model, and Bland-Altman plots. Reliability analyses included the intraclass correlation coefficient (ICC), the coefficient of variation (CV%), and the paired-sample t test. Sensitivity analyses included the typical error and smallest worthwhile change (SWC). The results showed that validity, reliability, and sensitivity values were higher for the CODTimer app (r = 0.99, R2 = 0.99, mean bias = -0.03 ± 0.10, CV% = 3.21, ICC = 0.89, SWC rating: good, p = 0.84) and the Seconds Count app (r = 0.99, R2 = 0.99, mean bias = -0.03 ± 0.08, CV% = 3.28, ICC = 0.88, SWC rating: good, p = 0.84) relative to the StopwatchCamera app (r = 0.98, R2 = 0.97, mean bias = -0.11 ± 0.22, CV% = 3.43, ICC = 0.86, SWC rating: marginal, p = 0.10), Analog Stopwatch 1 (r = 0.98, R2 = 0.96, mean bias = -0.09 ± 0.42, CV% = 2.95, ICC = 0.90, SWC rating: good, p = 0.91), and Analog Stopwatch 2 (r = 0.99, R2 = 0.97, mean bias = -0.12 ± 0.88, CV% = 3.51, ICC = 0.87, SWC rating: marginal, p = 0.96). In conclusion, compared to timing gates, the CODTimer app and Seconds Count app provided lower measurement bias and higher sensitivity for assessing CODS performance.

Relation between VT1, VT2, and VO2max with the Special Wrestling Fitness Test in Youth Wrestlers: A Short Report.

This study investigated the relationship between peak oxygen uptake and ventilatory threshold 1 (VT1) and 2 (VT2) with the Special Wrestling Fitness Test variables. Thirteen wrestlers (male: six; female: seven) of Olympic freestyle wrestling were assessed. The Pearson's correlation coefficient (p < 0.05) was used to establish the relationship between variables. A positive correlation was found between VT1 with throws in set B (r = 0.77; p = 0.002; 95%CI = 0.37-0.93), total throws (r = 0.73; p = 0.004; 95%CI = 0.30-0.91), heart rate recovery (r = 0.58; p = 0.036; 95%CI = 0.05-0.86), and test index (r = -0.60; p = 0.031; 95%CI = -0.86-0.07); between VT2 and throws in set B (r = 0.57; p = 0.043; 95%CI = 0.01-0.86); and between peak oxygen uptake with throws in set B (r = 0.77; p = 0.002; 95%CI = 0.39-0.93), throws in set C (r = 0.64; p = 0.02; 95%CI = 0.12-0.89), and total throws (r = 0.72; p = 0.006; 95%CI = 0.28-0.91). In conclusion, the peak oxygen uptake and ventilatory thresholds correlated with specific Special Wrestling Fitness Test variables.

A Systematic Review with Meta-Analysis on the Effects of Plyometric-Jump Training on the Physical Fitness of Combat Sport Athletes.

We aimed to assess the athletic performance changes in combat sport athletes (CoSAs) after plyometric-jump training (PJT), compared to control conditions, through a systematic review with meta-analysis. Following PRISMA guidelines, three electronic databases were searched for includable articles, according to a PICOS approach. Using a random-effects model, Hedges' g effects sizes (ES) were calculated. Heterogeneity was assessed using the I2 statistic, with values of <25%, 25-75%, and >75% representing low, moderate, and high levels of heterogeneity, respectively. Statistical significance was set at p ≤ 0.05. The certainty of evidence was assessed using the GRADE approach. Twelve eligible articles were identified for systematic review, seven of high quality and five of moderate quality, according to the PEDro scale. The studies recruited taekwondo, silat, wrestling, judo, fencing, and karate athletes (292 total participants), including specific-active and active controls. Most participants had a mean age of <18 years and were males (n = 225). Compared to the control, PJT programmes, involving 4-12 weeks and 2-3 sessions per week, induced small to moderate improvements (ES = 0.47 to 1.04) in athletes' maximal strength (e.g., 1RM squat), vertical jump height, change-of-direction speed, and specific performance (e.g., fencing movement velocity), although without meaningful effects on body mass, fat mass, and muscle mass (ES = 0.02 to -0.06). Most (7 of 8) outcomes attained low heterogeneity. The outcome-level GRADE analysis indicated a certainty of evidence from low to moderate. In conclusion, PJT, when compared to control conditions, may improve CoSA athletic performance.

Effects of Strength Training on Physical Fitness of Olympic Combat Sports Athletes: A Systematic Review.

This review aimed to identify the effects of strength training programs on the physical fitness of Olympic combat sports (OCS) athletes. The systematic review included peer-reviewed articles that incorporated interventions that included pre- and post-intervention physical fitness assessment. The search was performed in the SCOPUS, PubMed, and Web of Science databases between April and September 2022. PRISMA and the TESTEX checklist were used to select and assess the methodological quality of the studies. Twenty studies with 504 participants (428 males and 76 females) were included. Significant improvements were found in athletes' maximal dynamic and isometric strength, muscle power, flexibility, and balance. In addition, improvements in favor of the training groups in specific actions of judo, karate, fencing, and boxing were observed. In conclusion, interventions aimed at the development of muscle strength in OCS, specifically in judo, boxing, karate, wrestling, and fencing, proved to be beneficial at a physical fitness level, resulting in significant increases in favor of the training groups with OCS, which could be used by trainers and coaches to improve the physical performance of athletes.

Exercise dosing considerations in times of COVID-19 pandemic: A review / Consideraciones sobre la dosificación de ejercicio en tiempos de pandemia de COVID-19: Una revisión

Introduction: During the COVID-19 pandemic, international organizations recommended regular physical exercise to maintain physical and mental health during confinement, however, it is an emerging disease, the evidence is not conclusive regarding the relationship between a physical inactivity and the risk of serious outcomes in patients with COVID-19, therefore, it is essential to identify the contribution of the type of physical exercise modality and the contribution to the immune system. Objective: To demonstrate the immunological response of different physical exercise modality in the population between 18 and 84 years of age, the population identified with the highest number of confirmed cases of COVID-19, in the report n°198 of the World Health Organization. Materials and methods: A review of the literature was carried out between Central Pubmed, Google Scholar and Scielo from January 2016 to December 2021. Results: Of the selected articles, it was possible to identify the main benefits in the immune response with both modalities of physical exercise (aerobic and/or resistance) in the target population. Conclusion: At present, the benefits on the immune response in patients with COVID-19 are completely unknown, which is why it is essential to identify the contribution on the immune response in different modalities of physical exercise in the population between 18-84 years of age.

Introducción: Durante la pandemia de COVID-19, organismos internacionales recomendaron ejercicio físico regular para mantener la salud física y mental durante el confinamiento, sin embargo, al tratarse de una enfermedad emergente, la evidencia no es concluyente en relación a una inactividad física y el riesgo de desenlaces graves en estos pacientes con COVID-19. Es fundamental identificar el aporte del tipo de modalidad de ejercicio físico al sistema inmunológico. Objetivo: Demostrar la respuesta inmunológica de las diferentes modalidades de ejercicio físico en la población de 18 a 84 años, población identificada con mayor número de casos confirmados de COVID-19, en el informe n°198 de la Organización Mundial de la Salud. Materiales y métodos: Revisión de la literatura entre Pubmed Central, Google Scholar y Scielo (enero de 2016 - diciembre de 2021). Resultados: De los artículos seleccionados se identificó los principales beneficios en la respuesta inmune con ambas modalidades de ejercicio físico (aeróbico y/o resistencia) en dicha población. Conclusión: En la actualidad se desconoce por completo los beneficios sobre la respuesta inmune en pacientes con COVID-19, por ello, es fundamental identificar el aporte sobre la respuesta inmune en diferentes modalidades de ejercicio físico en la población entre 18-84 años de edad.

Overweight and Obese Adult Patients Show Larger Benefits from Concurrent Training Compared with Pharmacological Metformin Treatment on Insulin Resistance and Fat Oxidation.

Metformin, a drug widely used to treat insulin resistance, and training that combines aerobic and strength exercise modalities (i.e., concurrent training) may improve insulin sensitivity. However, there is a paucity of clinical trials investigating the effects of concurrent training, particularly on insulin resistance and fat oxidation in overweight and obese patients. Furthermore, only a few studies have compared the effects of concurrent training with metformin treatment. Therefore, the aim of this study was to examine the effects of a 12-week concurrent training program versus pharmaceutical treatment with metformin on maximum fat oxidation, glucose metabolism, and insulin resistance in overweight or obese adult patients. Male and female patients with insulin resistance were allocated by convenience to a concurrent training group (n = 7 (2 males); age = 32.9 ± 8.3 years; body mass index = 30 ± 4.0 kg·m-2) or a metformin group (n = 7 (2 males); age = 34.4 ± 14.0 years; body mass index = 34.4 ± 6.0 kg·m-2). Before and after the interventions, all participants were assessed for total body mass, body mass index, fat mass, fat-free mass, maximum oxygen consumption, maximal fat oxidization during exercise, fasting glucose, and insulin resistance through the homeostatic model assessment (HOMA-IR). Due to non-normal distribution of the variable maximal fat oxidation, the Mann-Whitney U test was applied and revealed better maximal fat oxidization (Δ = 308%) in the exercise compared with the metformin group (Δ = -30.3%; p = 0.035). All other outcome variables were normally distributed, and significant group-by-time interactions were found for HOMA-IR (p < 0.001, Δ = -84.5%), fasting insulin (p < 0.001, Δ = -84.6%), and increased maximum oxygen consumption (p = 0.046, Δ = 12.3%) in favor of the exercise group. Similar changes were found in both groups for the remaining dependent variables. Concurrent training seems to be more effective compared with pharmaceutical metformin treatment to improve insulin resistance and fat oxidation in overweight and obese adult patients with insulin resistance. The rather small sample size calls for more research in this area.

Effects of plyometric training on softer vs. Harder surfaces on jump-related performance in rugby sevens players.

This study aimed to compare jump-related performance after plyometric training on harder vs. softer surfaces in rugby sevens players. Fourteen players were randomly assigned to the harder surface group (H-G, n = 7) and softer surface group (S-G, n = 7). Three times per week, in the morning, the players performed plyometric training on different surfaces and strength training. Before and after the 4-week intervention period, squat jump (SJ), countermovement jump (CMJ), and CMJ with arms (CMJA) tests were performed to measure vertical jump displacement (d), rate of force development (r), and power (p). The main results indicated a significant improvement in S-G for CMJd (∆% = +8.2%; p = 0.029; ES = 0.59) and for CMJAp (∆% = +8.7%; p = 0.035; ES = 0.44). These improvements were significant compared to H-G for CMJAd (F1,12 = 8.50; p = 0.013; η p 2 = 0.41; ES = 0.83) and CMJAp (F1,12 = 7.69; p = 0.017; η p 2 = 0.39; ES = 0.79). This study reveals that performance related to the counter movement jump with arms on softer surfaces after 4-week plyometric training improved vertical jump displacement and lower body power in rugby sevens players.

Effect of a Six Week In-Season Training Program on Wrestling-Specific Competitive Performance.

The effect of multi-component training on specific performance is under-researched in wrestlers. The aim of this study was to determine the effect of six weeks of multi-component training on The Special Wrestling Fitness Test (SWFT) performances of wrestlers who were preparing for an international championship, and to, additionally, determine their inter-individual adaptive variability. The wrestlers (n = 13; 7 females; all international level) underwent technical-tactical and physical fitness training for the six weeks before the championship, 12 sessions per week (i.e., 36 h per week). Before and after the intervention the athletes were assessed with the SWFT, a wrestling-specific competitive performance test that includes measurements for throws, heart rate response to the SWFT, and the SWFT index. Significant pre-post intervention improvements were noted for throws (pre = 23.5 ± 2.9; post = 24.9 ± 3.6; p = 0.022) and SWFTindex (pre = 14.9 ± 2.2; post = 14.1 ± 2.2; p = 0.013. In conclusion, six weeks of multi-component training improved wrestling-specific competitive performances in highly-trained wrestlers, although with a meaningful inter-subject variability.

Can the immunological system of the upper respiratory tract, improved by physical exercise, act as a first immunological barrier against SARS-CoV-2?

INTRODUCTION: The main route of transmission of SARS-CoV-2 is the upper respiratory tract via cell membranes, including angiotensin-converting enzyme 2 (ACE2) and transmembrane host-associated serine protease transmembrane serine protease 2 (TMPRSS2). Both enzymes present in the nasal epithelium are the first direct point of contact for SARS-CoV-2. In this sense, the mucosal immune mechanisms of the upper respiratory tract, including immunoglobulin A (IgA), could be enhanced by physical exercise and be the first defense mechanism against the transmission and infection of SARS-CoV-2. AREAS COVERED: The authors reviewed recent biomedical literature available in databases related to the effects of exercise and training modalities on IgA concentration levels in the upper respiratory tract in different populations. EXPERT OPINION: According to the biomedical literature reviewed, physical exercise can decrease or improve the level of IgA concentrations. However, it is important to take into account factors such as training load, recovery during the exercise session and between training, as well as the exercise modality. Furthermore, the characteristics of the target population should be taken into account to maximize the adaptive immune response to adequately strengthen the upper respiratory tract and potentially be a barrier against SARS-CoV-2 infection.

Effects of High-Intensity Interval Training With Specific Techniques on Jumping Ability and Change of Direction Speed in Karate Athletes: An Inter-individual Analysis.

This study investigated the effect of 4weeks of high-intensity interval training (HIIT) with specific techniques and analyzed inter-individual variability [classified in responders (Rs) and non-responders (NRs)] on jumping ability and change of direction speed (CODS) in youth karate athletes. Athletes of both genders (n=10) were randomly assigned into experimental group (EG; n=5) and the control group (CG; n=5). The EG trained 2-3days per week applying HIIT (three rounds [15 sets of 4s all-out specific efforts with 8s of dynamical pauses] with 3min of recovery between rounds) during their usual training during 4weeks. Assessments included squat jump (SJ) and countermovement jump (CMJ) and CODS by T-test. No significant interaction effect group by time was found. Although, in percentage and effect size (ES) terms increases were reported in both groups for SJ (EG: 15.2%, ES=0.91 vs. CG: 12.4%, ES=0.02) and only in EG for the T-test (-1.7%; ES=-0.35). In turn, a trend toward a higher proportion of Rs was observed in the EG (40% Rs) vs. CG (20% Rs) for SJ and CODS, respectively. In conclusion, the addition to regular training of a HIIT with specific techniques and based on the temporal combat structure after 4weeks was not a sufficient stimulus to increase jumping ability and CODS in karate athletes.

Inter-Individual Variability of a High-Intensity Interval Training With Specific Techniques vs. Repeated Sprints Program in Sport-Related Fitness of Taekwondo Athletes.

This study investigated the effect of 4 weeks of high-intensity interval training (HIIT) with specific techniques (TS-G) vs. repeated sprints (RS-G) and analyzed the inter-individual variability [classified into responders (Rs) and non-responders (NRs)] on sport-related fitness in taekwondo (TKD) athletes. Athletes of both genders (n = 12) were randomly assigned into TS-G and RS-G groups. Both groups trained 3 days/week for 4 weeks [two blocks of three rounds of 2 min of activity (4-s of all-out efforts with 28-s dynamical pauses) with 1 min of recovery in between and 5 min between blocks] during their regular training. The related sport fitness assessments included squat jump (SJ), countermovement jump (CMJ), multiple frequency speed of kick test (FSKTMULT), specifically total kicks and Kick Decrement Index (KDI), and 20-m shuttle run (20MSR). Relevant results indicate a significant effect of the time factor in both groups for SJ performance and a significant decrease for KDI in RS-G. In addition, an improvement in performance according to the effect size analysis in the TS-G in total kicks, KDI, and 20MSR. Complementarily, a higher proportion of athlete Rs was reported in TS-G vs. RS-G for SJ (50% vs. 30.3%, respectively), CMJ, and total kicks (16.6% vs. 0%). In conclusion, the addition to the regular training of a HIIT with specific-techniques and repeated-sprints associated with intervals and similar structure of the combat during 4 weeks of training can improve the concentric characteristics of lower limb performance, although they were not the sufficient stimuli in the other components of TKD-related fitness.

Distanciamiento físico y uso de máscaras faciales durante la actividad física escolar en pandemia covid-19: una breve comunicación / Physical distancing and use of face masks during school physical activity in the covid-19 pandemic: A brief communication

Resumen Azócar-Gallardo, J., Ojeda-Aravena, A., y Báez-San Martín, E. (2021). Distanciamiento físico y uso de máscaras faciales durante la actividad física escolar en pandemia Covid-19: Una breve comunicación. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(2), 1-9. Con el objetivo de reducir la transmisión del virus Síndrome Respiratorio Agudo Severo Coronavirus 2 (SARS-CoV-2) que genera la enfermedad por coronavirus 2019 (COVID-19) a nivel global, los gobiernos han adoptado múltiples políticas sanitarias. Entre las principales medidas potenciales para la disminución del riesgo de contagio se incluyen el distanciamiento físico o social, establecido en 1.5 m, y el uso de máscaras faciales. No obstante, este distanciamiento físico sugerido no es el recomendable durante la actividad física. Por otra parte, la Organización Mundial de la Salud no recomienda el uso de máscara facial durante la actividad física en adultos y en niños. Además, con el retorno a las clases presenciales y, en especial, la realización de actividad física escolar puede implicar un mayor riesgo de contagio al considerar los desplazamientos improvisados y si esta se realiza en espacios reducidos. Por lo tanto, la presente comunicación tiene por objetivo examinar la evidencia en torno al distanciamiento físico o social y el uso de la máscara facial en los escolares durante la realización de las diferentes actividades físicas escolares.

Abstract Azócar-Gallardo, J., Ojeda-Aravena, A., & Báez-San Martín, E. (2021). Physical distancing and use of face masks during school physical activity in the covid-19 pandemic: A brief communication. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(2), 1-9. Governments have adopted multiple health policies in order to reduce the transmission of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that causes the coronavirus disease 2019 (COVID-19) at a global level. The major potential measures for diminishing the risk of infection include physical or social distancing, set at 1.5 m, and the use of face masks. This physical distancing, however, is not the recommended one for physical activity. On the other hand, the World Health Organization does not recommend wearing face masks during physical activity in adults and children. In addition, the return to in-person classes and, especially, carrying out school physical activity may involve a greater risk of contagion, when considering improvised displacements and whether this is carried out in small spaces. The present communiqué, therefore, is aimed at examining the evidence related to physical or social distancing and the use of face masks by schoolchildren when carrying out various school physical activities.

Resumo Azócar-Gallardo, J., Ojeda-Aravena, A., e Báez-San Martín, E. (2021). Distanciamento físico e uso de máscaras faciais durante a atividade física escolar na pandemia covid-19: Uma breve comunicação. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 19(2), 1-9. Com o objetivo de reduzir a transmissão da Síndrome Respiratória Aguda Grave Coronavirus 2 (SARS-CoV-2) que gera a doença coronavírus 2019 (COVID-19) globalmente, os governos adotaram múltiplas políticas de saúde. Entre as principais medidas potenciais para a redução do risco de contágio estão o distanciamento físico ou social, estabelecido em 1,5 m, e o uso de máscaras faciais. No entanto, isso sugere que o distanciamento físico proposto não é o recomendável durante a atividade física. Por outro lado, a Organização Mundial da Saúde não orienta o uso de máscara facial durante a atividade física em adultos e crianças. Além disso, com a volta às aulas presenciais e, em particular, à realização da atividade física escolar pode resultar em um maior risco de contágio ao considerar deslocamentos improvisados e, ainda mais, se forem realizados em espaços pequenos. Portanto, esta comunicação tem como objetivo examinar as evidências em torno do distanciamento físico ou social e o uso de máscaras faciais em estudantes durante a realização de diferentes atividades físicas escolares.

Effects of Olympic Combat Sports on Older Adults' Health Status: A Systematic Review.

The aim of this systematic review was to analyse the studies centered on the effects of Olympic combat sports (OCS [i.e., boxing, fencing, judo, karate, taekwondo, wrestling]) on older adults' physical-functional, physiological, and psychoemotional health status. The review comprised randomised-controlled trials with OCS interventions, including older adults (≥60 years), and measures of physical-functional, physiological, and/or psychoemotional health. The studies were searched through SCOPUS, PubMed/MEDLINE, Web of Science, PsycINFO, and EBSCO databases until 5 January 2021. The PRISMA-P and TESTEX scales were used to assess the quality of the selected studies. The protocol was registered in PROSPERO (code: CRD42020204034). Twelve OCS intervention studies were found (scored ≥ 60% for methodological quality), comprising 392 females and 343 males (mean age: 69.6 years), participating in boxing, judo, karate, and taekwondo. The qualitative analysis revealed that compared to controls, OCS training improved muscle strength, cardiorespiratory capacity, agility, balance, movement, attention, memory, mental health, anxiety, and stress tolerance. Meta-analysis was available only for the chair stand test, and an improvement was noted after OCS training compared to control. In conclusion, OCS interventions improves older adults' physical-functional, physiological, and psychoemotional health. Our systematic review confirms that OCS training has high adherence (greater than 80%) in older adults.

Effects of 4 Weeks of a Technique-Specific Protocol with High-Intensity Intervals on General and Specific Physical Fitness in Taekwondo Athletes: An Inter-Individual Analysis.

The aim of this research was to compare the effects of a technique-specific high-intensity interval training (HIIT) protocol vs. traditional taekwondo training on physical fitness and body composition in taekwondo athletes, as well as to analyse the inter-individual response. Utilising a parallel controlled design, sixteen male and female athletes (five females and 11 males) were randomly divided into an experimental group (EG) that participated in the technique-specific HIIT and a control group (CG) that participated in traditional taekwondo training. Both groups trained three days/week for four weeks. Squat jump (SJ), countermovement jump (CMJ), 5-metre sprint (5M), 20-metre shuttle run (20MSR), taekwondo specific agility test (TSAT), multiple frequency speed of kick test (FSKTMULT), total kicks, and kick decrement index (KDI), as well as body composition were evaluated. Results indicate that there are no significant differences (p > 0.05) in the factors group and time factor and group by time interaction (p > 0.05). Although percentage and effect size increases were documented for post-intervention fitness components in TSAT, total kicks, KDI, and 20MSR, responders and non-responders were also documented. In conclusion, a HIIT protocol based on taekwondo-specific technical movements does not report significant differences in fitness and body composition compared to traditional taekwondo training, nor inter-individual differences between athletes.