Influence of physical fitness and weight status on autonomic cardiac modulation in children.

BACKGROUND: This study provides reference values for cardiovascular modulation at rest, during maximal exercise test and recovery after exercise in Caucasian children according to weight status and cardiorespiratory fitness (CRF) level. Additionally, the current study analyzed several correlations between autonomic cardiovascular modulation, cardiorespiratory performance and cardiometabolic risk. The principal goal of this study was to analyze cardiac function at rest, during maximum exercise, and during the recovery phase in children grouped according to weight status and CRF level. METHODS: One hundred and fifty-two healthy children (78 girls) 10-16 years of age were divided into three groups: soccer and basketball players (SBG), endurance group (EG), and sedentary people with overweight and obesity (OOG). A cardiac RR interval monitor recorded the cardiac data and specific software analyzed the cardiac autonomic response through heart rate (HR) and HR variability. The study analyzed resting HR (RHR), HRpeak, and HR recovery (HRR). RESULTS: OOG showed significant poorer performance in the Léger test lower V̇O2 max and higher values of blood pressure at rest and post-exercise than sport groups. The EG presented the best results in CRF and cardiometabolic risk (CMR) in relation to SBG and OOG. The OOG showed higher percentage of HR values, compatible with an unhealthy cardiovascular autonomic modulation than the sport groups, with significant differences in bradycardia, HR reserve, and HRR 5 min. CONCLUSIONS: Aerobic performance, vagal activity, blood pressure, chronotropic competence, and HRR have significant associations with CMR parameters. IMPACT: The current study presents reference values of autonomic cardiac function in Caucasian children according to weight status and cardiorespiratory fitness level. Aerobic performance, vagal activity, blood pressure, chronotropic competence, and heart rate during the recovery period after exercise have significant associations with cardiometabolic risk parameters. Children with overweight and obesity show signs of autonomic dysfunction reflected as low cardiac vagal activity and poor chronotropic competence.

Effect of COVID-19 confinement on physical activity patterns in relation to sociodemographic parameters in Spanish population.

BACKGROUND: The main purpose of the present study was to determine the sociodemographic parameters associated to physical activity (PA) patterns changes during the COVID-19 lockdown in the Spanish population. METHODS: Participants were recruited by sending a survey through various social network channels via the snowball method. A voluntary sample of 2430 individuals consisting of 1203 men and 1227 women (aged between 18 to 73 years old) from the Spanish national territory participated in this study. An online survey was performed to collect the information, which was tested through ad hoc analysis with different sociodemographic variables. Participants were a median of 34 years old (18-73 years old) with a mean BMI of 23.6 kg/m2. RESULTS: The risk factors associated with the change in PA hours during confinement showed that to do sports (ß=-56.88, 95% CI: -79.35 to -34.40, P<0.001), male sex (ß -34.78, 95%CI;-54.02 to -15.52, P<0.001) and the educational level (i.e., elementary school category) (ß=-54.21, 95%CI;-89.10 to -19.32, P=0.002) reported negative changes with hours of PA during confinement. By the contrary, the employment status (passive work) and to be student reported positive association (i.e., increase PA hours per week). CONCLUSIONS: The COVID-19 lockdown led to a reduction PA patterns in Spanish population. Mostly men showed a drastic decrease in hours of PA compared to the women's group. Likewise, the groups of people with elementary and high education showed a decrease in hours of weekly PA, as well as unemployed people.

Comprehensive cardiac evaluation to maximal exercise in a contemporary population of prepubertal children.

BACKGROUND: Heart rate (HR) is a biomarker used to measure physiological function, health status and cardiovascular autonomic function. The purpose of this study was to determine sex- and age-specific reference values for cardiac autonomic function at rest, during maximal exercise and the recovery phase in prepubertal children. METHODS: Five hundred and twelve healthy children 7-11 years of age performed a Léger test. A heart RR-interval monitor recorded the heart data and a specific software analysed the cardiac autonomic response through HR and HR variability (HRV). It analysed HR before the test (resting HR, RHR), during the test (HRpeak) and HR recovery (HRR) in the first minute (HRR1) and the fifth minute (HRR5). The values are mean ± SD. RESULTS: Collectively, 91.2% of girls and 92.3% of boys were within the recommended ranges regarding RHR. The average HRpeak was 199 ± 10.83 b.p.m. and 96.8% of girls and 95.3% of boys were within the minimum threshold value recommended (180 b.p.m.). Boys showed lower values of RHR than girls (p < 0.001) and larger values of HRR 1 and HRR5 (p < 0.001). CONCLUSIONS: This study comprehensively provides a reference set of data for the most important HR variables that can be obtained during exercise testing in prepubertal children regarding age and sex and in a field setting. IMPACT: This is the first study to provide reference values of autonomic cardiac function at rest, during maximal exercise and during the recovery period in prepubertal children aged 7-11 years. Despite the early age of participants, cardiorespiratory fitness, RHR and HRR are different according to sex. Aerobic performance and HRpeak have a negative correlation with body mass index and cardiometabolic risk.