Quadriceps muscle reaction time in obese children.

This study aimed to determine the influence of obesity, according to body mass index (BMI) and fat mass percentage, on quadriceps muscle reaction times. The study utilized a cross-sectional design. The sample size consisted of 42 schoolchildren (54.5% girls) aged 11 to 12 years old. Participant measurements included weight and height, which were used to categorize individuals based on BMI. Additionally, the electrical bioimpedance technique was employed to categorize participants based on their body fat percentage. A sudden destabilization test of the lower limb was performed to assess the reaction time of the rectus femoris, vastus medialis, and vastus lateralis muscles. The results show that overweight/obese children have a longer muscle reaction time for both the rectus femoris (ß = 18.13; p = 0.048) and the vastus lateralis (ß = 14.51; p = 0.042). Likewise, when the children were classified by percentage of body fat the results showed that overfat/obese children have a longer muscle reaction time for both the rectus femoris (ß = 18.13; p = 0.048) and the vastus lateralis (ß = 14.51; p = 0.042). Our results indicate that BMI and fat mass classification negativity alter the muscle reaction time in children. Overweight/obese or overfat/obese children showed longer reaction times in the rectus femoris and vastus lateralis muscles compared to children with normal weight. Based on these findings, it is suggested that in overweight and obese children, efforts not only focus on reducing body weight but that be complemented with training and/or rehabilitation programs that focus on preserving the normal physiological function of the musculoskeletal system.

Frailty, Seasonal Sensitivity and Health-related Quality of Life in Older People Living in High Southern Latitudes: a Bayesian Analysis.

Background: In older people, a notable research gap exists regarding the intricate dynamics between frailty, seasonal sensitivity, and health-related quality of life (HRQoL). This study aimed to determine the association between frailty, seasonal sensitivity, and HRQoL in older people from high southern latitudes. Methods: A cross-sectional observational study was conducted. Frailty, seasonal sensitivity, and HRQoL measurements were self-reported by participants through questionnaires. A total of 118 older people were recruited from a local community. The participants were selected through intentional non-probabilistic sampling. Results: The adjusted models showed a trend where lower education was associated with a higher risk of frailty (BF = 0.218). For frailty and HRQoL, we observed a trend suggesting that HRQoL decreases with increasing severity of frailty (BF = 1.76). In addition, we observed a linear effect based on the severity of seasonal sensitivity, meaning that older people with higher perceived severity report a proportional decrease in HRQoL (BF = 6.66). Conclusion: Sociodemographic factors, such as lower education levels, have increased the risk of frailty. At the same time, frailty and seasonal sensitivity perceived severity were associated with a lower HRQoL in older people.

Next steps to advance general physical activity recommendations towards physical exercise prescription: a narrative review.

Physical inactivity is a major health concern, associated with the development of several non-communicable diseases and with an increased mortality rate. Therefore, promoting active lifestyles has become a crucial public health necessity for enhancing overall health and quality of life. The WHO guidelines for physical activity (PA) present valuable contributions in this respect; however, we believe that greater specificity should be added or complemented towards physical exercise (PE) testing, prescription and programming in future recommendations. In this review article, we suggest simple and practical tools accessible to the entire population to improve the specificity of this approach, highlighting aspects of PE programming used by trained subjects. By adopting these suggestions, exercise professionals, clinicians and physical trainers can optimise the current general PA recommendations towards PE prescription to improve fitness status and encourage PE adherence in the general population.

Effectiveness of elastic band training and group-based dance on physical-functional performance in older women with sarcopenia: a pilot study.

BACKGROUND: Sarcopenia is a syndrome associated with aging that causes progressive loss of skeletal muscle mass and muscle function. In this pilot study, we compared the effectiveness of elastic band training regarding group-based dance on fat mass, fat-free mass, handgrip strength (HGS; dominant and non-dominant hand), leg strength, timed up-and-go (TUG) and walking speed in older women with sarcopenia. METHODS: This is a randomized controlled trial, single-blind, repeated measures of parallel groups (elastic band group: EBG, n = 21; group-based dance: GBD, n = 19), and a quantitative methodology. Three 60-minute sessions per week for 12 weeks were dedicated to the interventions with pre- and post-assessments. A two-factor mixed analysis of variance (ANOVA) model with repeated measures was performed to measure the group×time effect. RESULTS: A significant interaction revealed for fat-free mass (F1,16= 18.91; p < 0.001; EBG + 10.9% vs. GBD - 1.97%), HGS dominant hand (F1,16= 7.44; p = 0.014; EBG + 10.9% vs. GBD + 0.59%), HGS non-dominant hand (F1,16= 6.41; p = 0.022; EBG + 10.21% vs. GBD + 3.80%), leg strength (F1,16= 17.98; p < 0.001; EBG + 9.1% vs. GBD + 3.83%), TUG (F1,16= 7.52; p = 0.014; EBG - 14.7% vs. GBD - 1.0%) and walking speed (F1,16 = 6.40; p = 0.019; EBG - 7.6% vs. GBD - 4.35%) in favor of EBG. CONCLUSION: Elastic band training produces significantly greater responses on physical-functional performance regarding group-based dance in older women with sarcopenia. On the other hand, the EBG revealed a significant improvement in fat-free mass and upper and lower limb muscle strength, as well as a significant decrease time in TUG, and walking speed. Elastic band exercise is a safe, easy, affordable, and effective physical activity strategy, according to the findings.

Sleep impairment and altered pattern of circadian biomarkers during a long-term Antarctic summer camp.

Antarctic expeditions include isolation and exposure to cold and extreme photoperiods (with continuous natural light during summer) that may influence psychophysiological responses modulated by luminosity and sleep. We assessed changes in night sleep patterns by actigraphy, salivary biomarkers, and perceptual variables in seven participants in the following time points along a 50-day camping expedition in Antarctica (Nelson Island): Pre-Field (i.e., on the ship before camp), Field-1, Field-2, Field-3, Field-4 (from 1st to 10th, 11th to 20th, 21st to 35th and 36th to 50th days in camp, respectively), and Post-Field (on the ship after camp). We also characterized mood states, daytime sleepiness, and sleep quality by questionnaires. Staying in an Antarctic camp reduced sleep efficiency (5.2%) and increased the number of awakenings and wakefulness after sleep onset (51.8% and 67.1%, respectively). Furthermore, transient increases in time in bed (16.5%) and sleep onset latency (4.8 ± 4.0 min, from Pre- to Field-3) was observed. These changes were accompanied by an altered pattern of the emerging circadian marker ß-Arrestin-1 and a trend to reduce nocturnal melatonin [57.1%; P = 0.066, with large effect size (ES) from Pre-Field to Field-2 (ES = 1.2) and Field-3 (ES = 1.2)]. All changes returned to Pre-Field values during the Post-Field. The volunteers reported sleep-related physical complaints (feeling of cold and pain, discomfort to breathe, and cough or loud snoring), excessive daytime sleepiness, and reduced vigor during the camp. Thus, a 50-day camp alters neuroendocrine regulation and induces physical discomfort, which may explain the impaired sleep pattern and the consequent daytime sleepiness and mood changes.

Cardiac autonomic regulation in response to functional power threshold testing in elite cyclists / Regulación autonómica cardiaca en respuesta a la prueba de umbral de potencia funcional en ciclistas deélite

Objective: To evaluate the impact of a functional power threshold test (FTP) on cardiac autonomic regulation indicators in high performance cyclists.Methods: A total of 12 male elite cyclists (mean age 36.1 ± 11.2 years) were recruited. Body composition parameters were measured usingbioimpedancemetry and heart rate variability (HRV) before and after the application of the FTP assessment. Results: We observed that a greater sympathetic nervous system (SNS) index and Stress index on baseline were correlated with a smaller decrease in theparasympathetic nervous system (PNS) activity in response to the FTP test (ρ= 0.69, p = 0.013). Concerning morphological parameters, the skeletalmuscle index (SMI) was the only one that was inversely correlated with ∆PNS (ρ= -0.69, p = 0.02) whereas the muscle-bone index (MBI) displayed apositive correlation with ∆SNS (ρ = 0.82, p = 0.001). In fully adjusted models we found that waist-to-hip ratio (β= 7.90, CI95%[4.16, 11.63], t(8) = 4.88, p =0.001) and SMI significantly influenced ∆PNS (β = -1.38, CI95%[-1.84, -0.92], t(8) = -6.94, p < 0.001), whereas MBI (β= 10.26, CI95%[8.10, 12.42], t(8) =10.96, p < 0.001) and the interaction between the latter and Power achieved during FTP influenced ∆SNS (β = -0.05, CI95%[-0.09, -4.99e-03], t(8) = -2.56, p= 0.033). Conclusion: Our findings indicate that the SMI had a negative effect on the ∆PNS, while the MBI was positively correlated with the ∆SNS in cyclists. Thesefindings suggest that a higher SMI and MBI could have a detrimental impact on the cardiac autonomic response to maximal aerobic exercise in high-performance cyclists, such as FTP.(AU)

Objetivo: Evaluar el impacto de una prueba de umbral de potencia funcional (FTP) sobre los indicadores de regulación autonómica cardiaca en ciclistasde alto rendimiento. Métodos: Se reclutó a un total de 12 ciclistas de élite masculinos (edad media 36.1 ± 11.2 años). Se midieron los parámetros de composición corporalmediante bioimpedanciometría y la variabilidad de la frecuencia cardiaca (HRV) antes y después de la aplicación de la evaluación del FTP. Resultados: Observamos que un mayor índice del sistema nervioso simpático (SNS) e índice de estrés basalmente se correlacionaron con una menordisminución de la actividad del sistema nervioso parasimpático (PNS) en respuesta a la prueba FTP (ρ= 0.69, p = 0.013). En cuanto a los parámetrosmorfológicos, el índice músculo esquelético (SMI) fue el único que se correlacionó inversamente con el ∆PNS (ρ= -0.69, p = 0.02) mientras que el índicemúsculo-hueso (MBI) mostró una correlación positiva con ∆SNS (ρ = 0.82, p = 0.001). En los modelos totalmente ajustados encontramos que la relacióncintura-cadera (β= 7.90, CI95%[4.16, 11.63], t(8) = 4.88, p = 0.001) y el SMI influían significativamente en el ∆PNS (β= -1.38, CI95%[-1.84, -0.92], t(8) = -6.94,p < 0.001), mientras que el MBI (β = 10.26, CI95%[8.10, 12.42], t(8) = 10.96, p < 0.001) y la interacción entre este último y la Potencia alcanzada durante elFTP influían en el ∆SNS (β= -0.05, CI95%[-0.09, -4.99e-03], t(8) = -2.56, p = 0.033). Conclusión: Nuestros hallazgos indican que el SMI tuvo un efecto negativo sobre el ∆PNS, mientras que el MBI se correlacionó positivamente con el ∆SNSen ciclistas. Estos hallazgos sugieren que un mayor SMI y MBI podrían tener un impacto perjudicial en la respuesta autonómica cardíaca al ejercicioaeróbico máximo en ciclistas de alto rendimiento, como el FTP.(AU)

Hand rehabilitation based on the RobHand exoskeleton in stroke patients: A case series study.

Introduction: The RobHand (Robot for Hand Rehabilitation) is a robotic neuromotor rehabilitation exoskeleton that assists in performing flexion and extension movements of the fingers. The present case study assesses changes in manual function and hand muscle strength of four selected stroke patients after completion of an established training program. In addition, safety and user satisfaction are also evaluated. Methods: The training program consisted of 16 sessions; two 60-minute training sessions per week for eight consecutive weeks. During each session, patients moved through six consecutive rehabilitation stages using the RobHand. Manual function assessments were applied before and after the training program and safety tests were carried out after each session. A user evaluation questionnaire was filled out after each patient completed the program. Results: The safety test showed the absence of significant adverse events, such as skin lesions or fatigue. An average score of 4 out of 5 was obtained on the Quebec User Evaluation of Satisfaction with Assistive Technology 2.0 Scale. Users were very satisfied with the weight, comfort, and quality of professional services. A Kruskal-Wallis test revealed that there were not statistically significant changes in the manual function tests between the beginning and the end of the training program. Discussion: It can be concluded that the RobHand is a safe rehabilitation technology and users were satisfied with the system. No statistically significant differences in manual function were found. This could be due to the high influence of the stroke stage on motor recovery since the study was performed with chronic patients. Hence, future studies should evaluate the rehabilitation effectiveness of the repetitive use of the RobHand exoskeleton on subacute patients. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT05598892?id=NCT05598892&draw=2&rank=1, identifier NCT05598892.

Validity and Reliability of Short-Term Heart Rate Variability Parameters in Older People in Response to Physical Exercise.

BACKGROUND: Currently, and to the best of our knowledge, there is no standardized protocol to measure the effect of low- to moderate-intensity physical exercise on autonomic modulation focused in older people. AIM: Validate a test-retest short-term exercise protocol for measuring the autonomic response through HRV in older people. METHODS: A test-retest study design was used. The participants were selected through intentional non-probabilistic sampling. A total of 105 older people (male: 21.9%; female: 78.1%) were recruited from a local community. The assessment protocol evaluated HRV before and immediately after the 2-min step test. It was performed twice on the same day, considering a time of three chronological hours between the two measurements. RESULTS: The posterior distribution of estimated responses in the Bayesian framework suggests moderate to strong evidence favoring a null effect between measurements. In addition, there was moderate to robust agreement between heart rate variability (HRV) indices and assessments, except for low frequency and very low frequency, which showed weak agreement. CONCLUSIONS: Our results provide moderate to strong evidence for using HRV to measure cardiac autonomic response to moderate exercise, suggesting that it is sufficiently reliable to show similar results to those shown in this test-retest protocol.

A 7-Week Summer Camp in Antarctica Induces Fluctuations on Human Oral Microbiome, Pro-Inflammatory Markers and Metabolic Hormones Profile.

Antarctic camps pose psychophysiological challenges related to isolated, confined, and extreme (ICE) conditions, including meals composed of sealed food. ICE conditions can influence the microbiome and inflammatory responses. Seven expeditioners took part in a 7-week Antarctic summer camp (Nelson Island) and were evaluated at Pre-Camp (i.e., at the beginning of the ship travel), Camp-Initial (i.e., 4th and 5th day in camp), Camp-Middle (i.e., 19th-20th, and 33rd-34th days), Camp-Final (i.e., 45th-46th day), and at the Post-Camp (on the ship). At the Pre-Camp, Camp-Initial, and Camp-Final, we assessed microbiome and inflammatory markers. Catecholamines were accessed Pre- and Post-Camp. Heart rate variability (HRV), leptin, thyroid stimulating hormone (TSH), and thyroxine (T4) were accessed at all time points. Students' t-tests or repeated-measures analysis of variance (one or two-way ANOVA) followed by Student-Newman-Keuls (post hoc) were used for parametric analysis. Kruskal-Wallis test was applied for non-parametric analysis. Microbiome analysis showed a predominance of Pseudomonadota (34.01%), Bacillota (29.82%), and Bacteroidota (18.54%), followed by Actinomycetota (5.85%), and Fusobacteria (5.74%). Staying in a long-term Antarctic camp resulted in microbiome fluctuations with a reduction in Pseudomonadota-a "microbial signature" of disease. However, the pro-inflammatory marker leptin and IL-8 tended to increase, and the angiogenic factor VEGF was reduced during camp. These results suggest that distinct Antarctic natural environments and behavioral factors modulate oral microbiome and inflammation.

Maximal pulmonary ventilation and lactate affect the anaerobic performance in young women exposed to hypobaric hypoxia.

Background: Athletes, tourists, and mining workers from all over the world ascend daily to an altitude greater than 3.000 meters above sea level to perform different activities, all of which demand physical effort. A ventilation increase is the first mechanism once the chemoreceptors perceive hypoxia, and is key to maintaining blood oxygen levels during acute exposure to high altitudes and to buffering lactic acidosis during exercise. It has been observed that gender is a variable that can influence the ventilatory response. Still, the available literature is limited due to the few studies considering women as study subjects. The influence of gender on anaerobic performance and its effects under high altitudes (HA) environments have been poorly studied. Objective: The objectives of this study were to evaluate anaerobic performance in young women exposed to high altitudes and to compare the physiological response to multiple sprints between women and men measured by ergospirometry. Methodology: Nine women and nine men (22.9 ± 3.2 years old) carried out the multiple-sprint anaerobic tests under two conditions, sea level and high altitudes. Results: In the first 24 h of exposure to a high altitudes, lactate levels were higher in women than those in men (2.57 ± 0.4 Mmol/L, 2.18 ± 0.3 Mmol/L, respectively; p < 0.05). Second, women had a decreased ventilatory response in exposure to high altitudes compared to men (p > 0.005). Third, there is a positive correlation between lactate levels prior to an anaerobic test and the ventilatory response developed by subjects at high altitudes (R2 = 0.33, slope = -41.7, and p < 0.05). Lastly, this ventilatory response can influence VO2peak (R2 = 0.60, slope = 0.02, and p < 0.001). Conclusion: This study provides insights into the mechanisms behind the reduced respiratory capacity observed in women during an anaerobic exercise test at high altitudes. An acute response to HA showed a greater work of breathing and increased the drive ventilatory response. It is possible to postulate the differences in the fatigue-induced metaboreflex of the respiratory muscles and aerobic-anaerobic transition between genders. These results on multiple sprint performance and the influences of gender in hypoxic environments deserve further investigation.

Physical Activity, Seasonal Sensitivity and Psychological Well-Being of People of Different Age Groups Living in Extreme Environments.

Physical activity can prevent many organic and mental pathologies. For people living in extreme southern high-latitude environments, weather conditions can affect these activities, altering their psychological well-being and favoring the prevalence of seasonal sensitivity (SS). This study aims to determine the relationships between the practice of physical activity, seasonal sensitivity and well-being in people living in high southern latitudes. A cross-sectional study was conducted, using the Seasonal Pattern Assessment Questionnaire (SPAQ), applying a psychological well-being scale, and determining sports practice according to the recommendations of the World Health Organization (WHO) for the 370 male (n = 209; 55%) and female (n = 173; 45%) participants. The main results indicated that 194 people (52 ± 7.7 years) reported physical activity. High-intensity physical activity practitioners recorded a significantly lower proportion of SS. In terms of psychological well-being, an adverse effect was found between the Seasonal Score Index (SSI) and five subcategories of the Ryff well-being scale. In conclusion, those who perform high-intensity physical activity have a lower SS, and those who have a higher SS have a lower psychological well-being.

Anthropometric Profile and Physical Activity Level as Predictors of Postural Balance in Overweight and Obese Children.

Overweightness and obesity can negatively influence many activities, including postural balance and locomotion, increasing predisposition to injury and risk of falls due to limitations on the biomechanics of daily living. The present study aimed to determine the influence of the anthropometric profile and physical activity level (PAL) on the postural balance of overweight and obese children. The sample included 387 schoolchildren (216 boys and 171 girls). The variables of the anthropometric profile studied were body mass, biped height, BMI, waist circumference, waist-to-hip ratio (WHR), summation of folds, body composition, and somatotype. PAL was measured using the PAQ-C questionnaire. Static and dynamic postural balance were measured through an open-eye (OE) and closed-eye (CE) posturographic test and the SEBTm, respectively. For static balance, the significant models were for mediolateral velocity (R2 = 0.42 in OA; R2 = 0.24 in OC), anteroposterior velocity (R2 = 0.21 in OA; R2 = 0.27 in OC), and mean velocity (R2 = 0.27 in OA; R2 = 0.46 in OC), where the predictors of low performance were younger age, male sex, overweight/obese nutritional status, greater thickness of skin folds, less tendency to mesomorphy, and greater fat mass. On the other hand, for dynamic postural balance, the significant models were observed in the previous direction (R2 = 0.39), posteromedial (R2 = 0.57), and posterolateral (R2 = 0.56), where the variables that predict a low performance were low PAL, overweight/obese nutritional status, and high WHR. Overweight and obese children presented a deficit in static and dynamic postural balance, enhanced by variables such as gender, age, PAL, and anthropometric characteristics related to adiposity.

Factors Associated with Poor Health-Related Quality of Life in Physically Active Older People.

This study aimed to associate morphological variables and physical fitness with health-related quality of life (HRQoL) in physically active older people. A cross-sectional study was carried out that evaluated 470 older people (89.57% female) with a mean age of 70.13 ± 6.57 years, residing in two regions of Chile. Morphological variables (body weight, bipedal height, waist circumference, body mass index, and waist to height ratio), physical fitness through the Senior Fitness Test protocol, and HRQoL using the SF-36 questionnaire were obtained. Logistic regression analysis was used to identify risk factors between morphological variables and physical fitness associated with HRQoL. The main results indicated that overweight (OR = 1.52; p = 0.034), a waist circumference with risk (OR = 1.56; p = 0.021), poor performance in the back scratch tests (OR = 1.02; p = 0.008) and timed up-and-go (OR = 1.19; p = 0.040) increased the probability of having a low general HRQoL. Also, the low performance of chair stand and arm curl tests was associated with poor physical and social dimensions of HRQoL (p < 0.05). In conclusion, a low HRQoL in physically active older people is associated with both morphological and physical fitness factors.

Concurrent training and interindividual response in women with a high number of metabolic syndrome risk factors.

The non-responders (NRs) after exercise training have been poorly studied in populations with morbid obesity. The purpose of this study was to determine the NR prevalence after 20 weeks of concurrent training of morbidly obese women with a high or low number of metabolic syndrome (MetS) risk factors. Twenty-eight women with morbid obesity participated in an exercise training intervention and were allocated into two groups distributed based on a high (≥3, n = 11) or low number (<3, n = 17) of MetS risk factors. The main outcomes were waist circumference (WC), fasting plasma glucose (FPG), high-density lipids (HDL-c), triglycerides (Tg), and systolic (SBP) and diastolic (DBP) blood pressure, and secondary outcomes were body composition, anthropometric and physical fitness, determined before and after 20 weeks of concurrent training. NRs were defined as previously used technical error cut-off points for the MetS outcomes. Significantly different (all p < 0.05) prevalences of NRs between the H-MetS vs. L-MetS groups (respectively) in WC (NRs 18.2 % vs. 41.1 %, p < 0.0001), SBP (NRs 72.7 % vs. 47.0 %, p = 0.022), DBP (NRs 54.5 % vs. 76.4 %, p < 0.0001), FPG (NRs 100% vs. 64.8 %, p < 0.0001), and HDL-c (NRs 90.9 % vs. 64.7 %, p = 0.012) were observed. In addition, the H-MetS group evidenced significant changes on ΔSBP (-10.2 ± 11.4 mmHg), ΔFPG (-5.8 ± 8.2 mg/dl), ΔHDL-c (+4.0 ± 5.9 mg/dl), and ΔTg (-8.8 ± 33.8 mg/dl), all p < 0.05. The L-MetS group only showed significant changes in ΔWC (-3.8 ± 5.0 cm, p = 0.009). Comparing H-MetS vs. L-MetS groups, significant differences were observed in ∆FPG (-5.8 ± 8.2 vs. +0.3 ± 3.2 mg/dl, p = 0.027), but not in other MetS outcomes. In conclusion, 20 weeks of concurrent training promotes greater beneficial effects in morbidly obese patients with a high number of MetS risk factors. However, the NR prevalence for improving MetS outcomes was significantly superior in these more-diseased groups in SBP, FPG, and HDL-c, independent of their major training-induced effects.

Effect of Confinement on Anxiety Symptoms and Sleep Quality during the COVID-19 Pandemic.

Confinement during the COVID-19 pandemic has significantly impacted lifestyles worldwide. The aim of this study was to evaluate the effect of confinement on anxiety symptoms and sleep quality in people living in extreme southern latitudes. The Beck Anxiety Inventory (BAI) and the Pittsburgh Sleep Quality Index (PSQI) were administered to 617 people, 74.2% of whom were women. The sample was grouped according to confinement: the zone of confinement (CZ) (46.5%) and the zone of partial confinement (PZ) (53.5%). In addition, the sample was further categorized into four age subgroups (18-25 years; 26-40 years; 41-50 years; over 50 years). Higher levels of anxiety and worse sleep quality were found in the CZ group than in the PZ group. Women had higher levels of anxiety and worse sleep quality than men. A significant bidirectional relationship between anxiety and sleep quality was observed, even after controlling for sex. This study demonstrated that women and young adults were more vulnerable to the effects of confinement on anxiety symptoms and sleep quality in populations at southern latitudes.

Relationship of cardiorespiratory control and vascular compliance in competitive young athletes / Relación entre el control cardiorrespiratorio y la distensibilidad vascular en atletas jóvenes de competición / Relação entre o controlo cardiorrespiratório e a conformidade vascular em jovens atletas competitivos

Objective: To study the haemodynamic properties of the peripheral circulation and its relationship with cardiorespiratory control, during anaerobicmuscle fatigue test, in young competitive athletes.Method: Nine adolescent of national and international competition level were recruited (age: 15.6 ± 1.9 years; male = 7) and cross-evaluated. Morphological measurements (body mass, percentage of total body fat and height), blood pressure (systolic, diastolic, mean and pulse blood pressure),respiratory measures (spirometry and pimometry), power, and fatigue were recorded through Wingate test.Results: Weight, height, and fat-free mass were positively correlated with the power parameters of the Wingate test (p < 0.05). The respiratoryparameters of forced vital capacity, peak expiratory flow, maximum inspiratory pressure (MIP) and maximum sustained pressure (SMIP) were alsosignificantly correlated with the power parameters. Additionally, the cardiorespiratory parameters of MIP and SMIP were positively correlated with pulsepressure at rest (p < 0.05).Conclusion: The increase in MIP and SMIP is associated with a lower arterial compliance, which indicates that a lower vascular elasticity influences agreater diaphragmatic strength and endurance of the young athlete.(AU)

Objetivo: Estudiar las propiedades hemodinámicas de la circulación periférica y su relación con el control cardiorrespiratorio, durante la prueba de fatiga muscular anaeróbica, en jóvenes atletas de competición.Método: Se reclutaron nueve adolescentes de nivel de competición nacional e internacional (edad: 15.6 ± 1.9 años; hombres = 7) y se evaluaron de forma cruzada. Se registraron medidas morfológicas (masa corporal, porcentaje de grasa corporal total y altura), presión arterial (presión arterial sistólica, diastólica, media y pulso), medidas respiratorias (espirometría y pimometría), potencia y fatiga mediante el test de Wingate. Resultados: El peso, la altura y la masa libre de grasa se correlacionaron positivamente con los parámetros de potencia del test de Wingate (p < 0.05). Los parámetros respiratorios de capacidad vital forzada, flujo espiratorio máximo, presión inspiratoria máxima (MIP) y presión inspiratoria máxima sostenida (SMIP) también se correlacionaron significativamente con los parámetros de potencia. Además, los parámetros cardiorrespiratorios de MIP ySMIP se correlacionaron positivamente con la presión del pulso en reposo (p < 0.05).Conclusión: El aumento de la MIP y SMIP se asocia a una menor compliance arterial, lo que indica que una menor elasticidad vascular influye en una mayor fuerza y resistencia diafragmática del joven atleta.(A)

Objetivo: Estudar as propriedades hemodinâmicas da circulação periférica e sua relação com o controle cardiorrespiratório, durante o teste de fadigamuscular anaeróbica, em jovens atletas competitivos.Método: Nove adolescentes de nível de competição nacional e internacional foram recrutados (idade: 15.6 ± 1.9 anos; masculino = 7) e avaliados de formacruzada. Medidas morfológicas (massa corporal, percentual de gordura corporal total e altura), pressão arterial (sistólica, diastólica, média e pulso),medidas respiratórias (espirometria e pimometria), potência e fadiga foram registradas através do teste Wingate.Resultados: Peso, altura e massa livre de gordura foram correlacionados positivamente com os parâmetros de potência do teste Wingate (p < 0.05). Osparâmetros respiratórios de capacidade vital forçada, pico de fluxo expiratório, pressão inspiratória máxima (MIP) e pressão inspiratória máximasustentada (SMIP) também foram significativamente correlacionados com os parâmetros de potência. Além disso, os parâmetros cardiorespiratórios daMIP e SMIP foram positivamente correlacionados com a pressão de pulso em repouso (p < 0.05).Conclusão: O aumento da MIP e SMIP está associado a uma menor complacência arterial, o que indica que uma menor elasticidade vascular influenciauma maior resistência diafragmática e resistência do jovem atleta.(AU)

[Functional characterization of patients with cerebral palsy living in the Magallanes region and the Chilean Antarctic]. / Caracterización funcional de pacientes con parálisis cerebral que viven en la región de Magallanes y la Antártica Chilena.

OBJECTIVE: To functionally characterize patients with Cerebral Palsy (CP) living in the Magallanes Re gion and the Chilean Antarctic. PATIENT AND METHOD: Descriptive-retrospective observational study of patients with cerebral palsy, registered in the Outpatient Rehabilitation Program of the Corporación de Rehabilitación Club de Leones Cruz del Sur de Punta Arenas between 1986 and 2018. Patients with CP were clinically categorized and then functionally characterized according to gross motor skills (GMFCS), manual ability (MACS), feeding ability (EDACS), and communication function (CFCS). RESULTS: 106 patients were included. Regarding the clinical classification, the most common type of CP was bilateral spastic paralysis, with the highest percentage of functional involvement in each of the evaluated areas, followed by unilateral spastic paralysis, while cases of dystonic CP and other non-classifiable types presented were less frequent. According to the clinical subclassification, spastic diplegia was more frequent, especially affecting manual and communication skills level I compared with hemiplegia, while cases of mixed and unclassifiable quadriplegia were less frequent with greater overall involvement of level I feeding skills. CONCLUSION: The observed results of CP in the Magalla nes Region and the Chilean Antarctic are similar to studies available in the literature. The complete evaluation and classification of patients with CP enable a better understanding of the pathology for future studies.

Heart rate variability, thyroid hormone concentration, and neuropsychological responses in Brazilian navy divers: a case report of diving in Antarctic freezing waters.

Open-water diving in a polar environment is a psychophysiological challenge to the human organism. We evaluated the effect of short-term diving (i.e., 10 min) in Antarctic waters on autonomic cardiac control, thyroid hormone concentration, body temperatures, mood, and neuropsychological responses (working memory and sleepiness). Data collection was carried out at baseline, before, and after diving in four individuals divided into the supporting (n=2) and diving (n=2) groups. In the latter group, autonomic cardiac control (by measuring heart rate variability) was also assessed during diving. Diving decreased thyroid-stimulating hormone (effect size = 1.6) and thyroxine (effect size = 2.1) concentrations; these responses were not observed for the supporting group. Diving also reduced both the parasympathetic (effect size = 2.6) and sympathetic activities to the heart (ES > 3.0). Besides, diving reduced auricular (effect size > 3.0), skin [i.e., hand (effect size = 1.2) and face (effect size = 1.5)] temperatures compared to pre-dive and reduced sleepiness state (effect size = 1.3) compared to basal, without changing performance in the working memory test. In conclusion, short-term diving in icy waters affects the hypothalamic-pituitary-thyroid axis, modulates autonomic cardiac control, and reduces body temperature, which seems to decrease sleepiness.

A 32-day long fieldwork in Antarctica improves heat tolerance during physical exercise.

We evaluated the influence of a 32-day camping in Antarctica on physical performance and exercise-induced thermoregulatory responses. In Brazil, before and after the Antarctic camping, the volunteers performed an incremental exercise at temperate conditions and, two days later, an exercise heat stress protocol (45-min running at 60% of maximum aerobic speed, at 31°C and 60% of relative humidity). In Antarctica, core temperature was assessed on a day of fieldwork, and average values higher than 38.5°C were reported. At pre- and post-Antarctica, physiological (whole-body and local sweat rate, number of active sweat glands, sweat gland output, core and skin temperatures) and perceptual (thermal comfort and sensation) variables were measured. The Antarctic camping improved the participants' performance and induced heat-related adaptations, as evidenced by sweat redistribution (lower in the chest but higher in grouped data from the forehead, forearm, and thigh) and reduced skin temperatures in the forehead and chest during the exercise heat stress protocol. Notwithstanding the acclimatization, the participants did not report differences of the thermal sensation and comfort. In conclusion, staying in an Antarctic camp for 32 days improved physical performance and elicited physiological adaptations to heat due to the physical exertion-induced hyperthermia in the field.

Cardiac Autonomic Modulation in Response to Muscle Fatigue and Sex Differences During Consecutive Competition Periods in Young Swimmers: A Longitudinal Study.

Objective: To study the differences in cardiac autonomic modulation in response to muscle fatigue caused by high-intensity exercise during two consecutive competition periods in young swimmers. Methods: Twenty-six competitive swimmers, selected by their training volume, were separated in two groups, females (n = 12 [46%], age: 13.5 ± 1.4 years) and males (n = 14 [54%], age: 13.9 ± 1.7 years), aged between 10 and 16 years, were evaluated five times as follow: (i) 21 days before the first competition (t-0); (ii) two days before (t-1; t-3); and (iii) two days after (t-2; t-4) of the first and second competitions. Morphological measurements (body mass, percentage of total body fat and height), blood pressure, power, and resting heart rate variability (RR with Polar band) were recorded before and after Wingate test at each time. Results: Body fat was higher in females compared to males. However, no differences were found in other morphological parameters. An intra-subject analysis grouped by sex in cardiovascular parameters shows longitudinal variations in systolic pressure and mean pressure among females. Additionally, females depicted higher, very low frequency (VLF, which is intrinsically generated by the heart and strongly associated with emotional stress) after physical fatigue compared to males at t-1. Further, before the competition, the high frequency (HF) component of HRV (parasympathetic drive) was higher in males than females at t-0 and t-4. Conclusion: Our data revealed that males displayed greater parasympathetic reactivity after an anaerobic muscle fatigue test during their competition periods. Contrarily, females had a less cardiac autonomic modulation when comparing the pre-post Wingate test after two consecutive competition periods.