Cardiorespiratory Fitness In Adolescents Research Articles

Eight weeks of high-intensity interval vs. sprint interval training effects on overweight and obese adolescents carried out during the cool-down period of physical education classes: randomized controlled trial.

The aim of this study was to evaluate the effect of sprint interval training (SIT) and [high intensive interval training (HIIT)] carried out during the cool-down period of the physical education classes on body composition, blood pressure variables (BP) and pulse rate (PR), and cardiorespiratory fitness of adolescents who are overweight and obese, and to compare the differences in enjoyment in response to SIT vs. HIIT. For this randomized controlled trial, forty-five adolescents were recruited from a high school and were randomly placed into three groups. SIT and HIIT trained for 8 weeks, twice a week, for 12 min/session. Experimental group (EG) 3 was the control, and they maintained their regular physical education class schedule. The SIT group performed 6 sets of 60 s of work (90-95%HRmax) / 60 s of rest (50-55%HRmax), and the HIIT group performed 3 sets of 2 min of work (80-85%HRmax) / 2 min of rest (50-55%HRmax). Both experimental groups showed a significant improvement in fat mass (FM) (%) and trunk FM (kg). In addition, EG2 reported a significance improvement in lean mass (kg), blood pressure BP (mmHG), systolic blood pressure (SBP) (mmHg), diastolic blood pressure (DBP) (mmHg), PR (bpm), and VO2max (ml/kg/min). The present study found that a HIIT protocol performed during the cool-down period of the physical education classes generated adaptations such as improvement in body composition, BP variables and PR, and cardiorespiratory fitness, in overweight and obese adolescents. In contrast, the group of overweight and obese adolescents who performed SIT showed limited benefits, with changes in fat mass only.

Adolescent Cardiorespiratory Fitness and Future Work Ability

Although research indicates that low fitness in youth is associated with a higher risk of chronic disability in men, the association of fitness in adolescence with work ability in working men and women remains unknown. To examine the associations of adolescent health-related physical fitness with future work ability. This 45-year observational cohort study, conducted in Finland, examined the direct and indirect longitudinal associations of objectively measured health-related fitness in adolescence (in 1976) with self-reported work ability and sickness absence in early middle age (in 2001) and the Work Ability Index in late middle age (in 2021). A countrywide stratified random baseline sample included fitness measurements for cardiorespiratory fitness (CRF) (running 1.5 km for girls and 2 km for boys), musculoskeletal fitness (MF; standing broad jump and sit-ups for both sexes, pull-ups for boys, and flexed-arm hang for girls), and height and weight, from which body mass index (BMI) was calculated. Structural equation modeling-based path analysis, adjusted for age and sex at baseline and for educational level, work-related physical strain, and leisure-time physical activity in late middle age, was conducted. Data analysis was performed from January to July 2023. Self-reported work ability was measured with structured questions in early middle age and with the validated Work Ability Index in late middle age. The final sample from longitudinal analyses (1207 individuals; 579 [48%] male individuals) consisted of participants with fitness measurement from age 12 to 19 years, and work ability assessment from age 37 to 44 years and/or age 57 to 64 years. Higher adolescent CRF was associated with higher work ability (839 participants; β = 0.12; 95% CI, 0.01 to 0.22; P = .03) and lower sickness absence (834 participants; β = -0.07; 95% CI, -0.12 to -0.02; P = .004) in early middle age and, indirectly, mediated by work ability in early middle age, with a higher work ability at the end of working age (603 participants; β = 0.04; 95% CI, 0.001 to 0.08; P = .04). The results remained consistent in both sexes and after adjustment for the confounders. Neither MF nor BMI was associated with work ability (MF, 1192 participants; β = -0.07; 95% CI, -0.17 to 0.03; BMI, 1207 participants, β = 0.09; 95% CI, -0.004 to 0.19) or sickness absence (MF, 1185 participants, β = 0.02; 95% CI, -0.03 to 0.06; BMI, 1202 participants, β = -0.03; 95% CI, -0.09 to 0.03) in early middle age or with late middle age work ability, mediated by work ability in early middle age (MF, 603 participants, β = -0.02; 95% CI, -0.06 to 0.01; BMI, 603 participants, β = 0.03; 95% CI, -0.004 to 0.07). These findings suggest that low CRF in youth is associated with poor work ability at the middle and end of working life, which highlights the informative and prognostic value of CRF assessment early in youth. Enhancing CRF in the first decades of life might contribute to better work capacity and productivity in the labor force, which would have implications for health, quality of life, society, and the economy.

IMPACTO DE EXERGAMES NO IMC E FATORES DE RISCO CARDIOVASCULAR: UMA REVISÃO SISTEMÁTICA

ABSTRACT Introduction: Exergames or active video games are digital platforms with functionality associated with body movement, which dialogue with improving physical activity levels, stimulating pleasure in practice and adherence to change habits, physically active behavior, and better quality of life. Objective: This study aimed to synthesize the available evidence on the contribution of exergame to Body Mass Index, physical activity level, glycemic control, blood pressure, and cardiorespiratory fitness in adolescents. Methods: This is a systematic review, reported following the PRISMA writing recommendations, without language restrictions, for articles indexed in the following databases: MEDLINE / PubMed, Embase, Cochrane Library, and Lilacs. Data extraction was performed analogously in a spreadsheet previously tested and standardized. The assessment of the risk of bias in the included studies was carried out by the RoB 1.0 tool in all of its domains in duplicate of reviewers. Initially, 3.039 studies were found. Results: The studies cover a total of 526 adolescents aged ten to 19. The most used platform in the studies was the Nintendo Wii, followed by the PlayStation, Xbox 360, and Dance Dance Revolution. The results indicated that interventions using exergames were effective for changing BMI, but there was no evidence on cardiovascular outcomes, with no effective changes in glycemic control and blood pressure and a significant response (p <0.05) in cardiorespiratory fitness. Conclusion: The exergame points to satisfactory results in improving health and can be incorporated as a relevant public policy in the adolescent health promotion. (PROSPERO Registration CRD42020181772). Level of evidence II; Therapeutic studies - investigation of treatment results.

Sleep duration and cardiorespiratory fitness in adolescents: Longitudinal analysis from the LabMed study.

We aimed to investigate longitudinal associations between sleep duration and cardiorespiratory fitness, in adolescents. Sleep duration was self-reported and cardiorespiratory fitness was assessed by the 20 m shuttle run test, both at baseline and follow-up (2-year follow-up). Participants were 734 Northern Portuguese adolescents (349 girls), aged 14.6 ± 1.8 years, from the LabMed study. Significant decreases were found between baseline and follow-up for sleep duration, whereas for cardiorespiratory fitness there was an increase. Adolescents with short sleep duration at baseline had lower cardiorespiratory fitness at follow-up, comparing to those meeting the sleep guidelines (odds ratio [OR] = 0.506, 95% confidence interval [CI]: 0.326-0.785; p = .002 for whole week; OR = 0.597, 95% CI: 0.407-0.875; p = .008 for weekdays). Girls who were short sleepers at baseline had lower odds of having a healthy cardiorespiratory fitness at follow-up, comparing to those meeting the sleep guidelines (OR = 0.311, 95% CI: 0.158-0.613; p < .001 for whole week; OR = 0.469, 95% CI: 0.262-0.838; p = .011 for weekdays). No significant associations between sleep duration and cardiorespiratory fitness were found for boys. There was a significant longitudinal association between short sleep duration and lower cardiorespiratory fitness levels, particularly in girls. Future interventions targeting adolescents' sleep duration should acknowledge behavioral differences between genders, as well as different behaviors adopted by boys ang girls, specifically on weekends.

Genetic and Environmental Factors and Cardiovascular Disease Risk in Adolescents

Cardiovascular risk factors in youth have been associated with future cardiovascular disease (CVD), but conventional observational studies are vulnerable to genetic and environmental confounding. To examine the role of genetic and environmental factors shared by full siblings in the association of adolescent cardiovascular risk factors with future CVD. This is a nationwide cohort study with full sibling comparisons. All men who underwent mandatory military conscription examinations in Sweden between 1972 and 1995 were followed up until December 31, 2016. Data analysis was performed from May 1 to November 10, 2022. Body mass index (BMI), cardiorespiratory fitness, blood pressure, handgrip strength, and a combined risk z score in late adolescence. The primary outcome was fatal or nonfatal CVD, as recorded in the National Inpatient Register or the Cause of Death Register before 2017. A total of 1 138 833 men (mean [SD] age, 18.3 [0.8] years), of whom 463 995 were full brothers, were followed up for a median (IQR) of 32.1 (26.7-37.7) years, during which 48 606 experienced a CVD outcome (18 598 among full brothers). All risk factors were associated with CVD, but the effect of controlling for unobserved genetic and environmental factors shared by full siblings varied. In the sibling analysis, hazard ratios for CVD (top vs bottom decile) were 2.10 (95% CI, 1.90-2.32) for BMI, 0.77 (95% CI, 0.68-0.88) for cardiorespiratory fitness, 1.45 (95% CI, 1.32-1.60) for systolic blood pressure, 0.90 (95% CI, 0.82-0.99) for handgrip strength, and 2.19 (95% CI, 1.96-2.46) for the combined z score. The percentage attenuation in these hazard ratios in the sibling vs total cohort analysis ranged from 1.1% for handgrip strength to 40.0% for cardiorespiratory fitness. Consequently, in the sibling analysis, the difference in cumulative CVD incidence at age 60 years (top vs bottom decile) was 7.2% (95% CI, 5.9%-8.6%) for BMI and 1.8% (95% CI, 1.0%-2.5%) for cardiorespiratory fitness. Similarly, in the sibling analysis, hypothetically shifting everyone in the worst deciles of BMI to the middle decile would prevent 14.9% of CVD at age 60 years, whereas the corresponding number for cardiorespiratory fitness was 5.3%. In this Swedish national cohort study, cardiovascular risk factors in late adolescence, especially a high BMI, were important targets for CVD prevention, independently of unobserved genetic and environmental factors shared by full siblings. However, the role of adolescent cardiorespiratory fitness in CVD may have been overstated by conventional observational studies.

The association of adolescent fitness with cardiometabolic diseases in late adulthood: A 45-year longitudinal study.

The aim of this study was to examine the associations of adolescent cardiorespiratory fitness (CRF), muscular fitness (MF), and speed-agility fitness (SA) with middle-aged cardiometabolic disease risk and explore sex differences. This 45-year prospective cohort study examined the associations between objectively measured fitness at adolescence (12-19 years) and physician-ascertained diabetes mellitus, elevated blood pressure (BP), and coronary heart disease reported either in early (37-44 years) or late (57-64 years) middle age, and self-measurement of waist circumference (WC) in late middle age. Fitness measurements for healthy adolescents in baseline included CRF (1.5 km [girls] and 2 km [boys] run), MF (standing broad jump, sit-ups, pull-ups [boys], and flexed-arm hang [girls]), and SA (50 m dash and 4 × 10 m shuttle run). Logistic regression and general linear models were adjusted for baseline age, sex, and body mass index (BMI), involving data from baseline and at least one follow-up measurement (N up to 1358, 47% males). Adolescent CRF was inversely, and regardless of adiposity, associated with middle age accumulated burden of cardiometabolic conditions in the whole sample (N = 562, ß = -0.10, 95% confidence intervals [CI] [-0.18, -0.03], p = 0.006), and elevated BP in females (N = 256, OR = 0.71, 95% CI [0.51, 0.91]). Overall, we observed stronger associations in females than in males. An inverse association of adolescent MF and SA with middle-aged WC was observed, but it did not show as consistent associations as with CRF. In this study, adolescent fitness, particularly CRF, was inversely associated with the burden of cardiometabolic conditions up to 45 years. Promotion of fitness in youth may be beneficial in preventing adulthood cardiometabolic diseases.

Body mass index and fitness in late adolescence and risk of cardiovascular disease, respiratory disease, and overall death after COVID-19.

Since obesity and poor fitness appear to be unfavorable for both cardiovascular health and coping with viral infections such as COVID-19, they are of specific interest in light of the increased risk of cardiovascular and respiratory events now seen after infection with SARS-CoV-2. Therefore, the aim of the present study was to investigate how body mass index (BMI) and cardiorespiratory fitness (CRF) in late adolescence are associated with the risk of cardiovascular disease (CVD), respiratory disease, and mortality after COVID-19. In this study, 1.5 million 18-year-old Swedish men with BMI and CRF measured during enlistment for military service 1968-2005 were included. Hospitalized and non-hospitalized COVID-19 cases were identified through the Patient Register or positive polymerase chain reaction tests, and age-matched with non-infected controls. CVD, respiratory disease, and mortality after COVID-19 were divided into <60days, 60-180days, >180days post-infection. Cox regression models were used. Hospitalized COVID-19 cases (n=9839), compared to controls, had >10-fold, 50 to 70-fold, and >70-fold hazards of CVD, respiratory disease, and mortality over the initial 60days post-infection with little variation across BMI or CRF categories. The elevated risks persisted at declining levels >180days. For non-hospitalized COVID-19 cases (n=181,822), there was a 4- to 7-fold increased acute mortality risk, and high CRF was associated with lower risk of post-infectious respiratory disease. The high hazards of adverse outcomes during the first two months after COVID-19 hospitalization, and across BMI and CRF categories, declined rapidly but were still elevated after six months. Adolescent CRF was associated with respiratory disease after COVID-19 without hospitalization, which gives further support to the health benefits of physical activity.

Lower adiponectin is associated with higher anthropometry and insulin resistance but not with low cardiorespiratory fitness in adolescents.

The aim of this study was to analyze the relationship between adiposity, cardiometabolic risk and cardiorespiratory fitness (CRF) according to different groups of adiponectin concentration. 255 adolescents of both sexes, aged 11-17years old, participated. Anthropometric and biochemical parameters such as body mass, height, abdominal circumference (AC), waist circumference (WC), fat mass, fat-free mass, total cholesterol (TC), high-density lipoprotein (HDL-c), low-density lipoprotein (LDL-c), triglycerides (TG), glucose, insulin, adiponectin, blood pressure, peak oxygen consumption (VO2peak) were measured. Body mass index (BMI), z-score BMI (BMI-z), triponderal mass index (TMI), waist-to-height ratio (WHtR), homeostasis model to assessment insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI) were calculated. Adiponectin was categorized: low adiponectin concentration (LAC ≤ 5.18µg/mL-1), intermediate (IAC = 5.18 and 7.63µg/mL-1) and high (HAC ≥ 7.63µg/ml-1). LAC showed higher BMI, BMI-z and TMI than the other groups (p < 0.05) and higher AC, WC and WHtR that the HAC (p < 0.05). IAC showed lower values of TC, LDL-c and TG, and the LAC presented the highest values of insulin, HOMA-IR and QUICKI (p < 0.05) to the IAC and HAC. HAC presented the lower VO2peak than the other groups (p < 0.01). BMI, TMI, glucose, insulin, HOMA-IR showed inverse, and QUICKI a direct and weak correlation with adiponectin (p < 0.05). No significant association was found between adiponectin and VO2peak (p > 0.05). The LAC group had higher means in the anthropometric variables and the worst results related to insulin resistance and sensitivity. Thus, adiponectin may play an important role in obesity and reduced concentration may be a factor in the development of obesity-associated morbidities.

Cardiorespiratory fitness in adolescents and young adults with Klinefelter syndrome - a pilot study.

Klinefelter syndrome (KS) may be associated with a wide spectrum of phenotypic changes including endocrine, metabolic, cognitive, psychiatric and cardiorespiratory pathologies in adults. However, in adolescence the clinical phenotype of KS is not well described, especially regarding physical fitness. The present study reports on cardiorespiratory function in adolescents and young adults with KS. Adolescents and young adults with KS were recruited in a cross-sectional pilot study. Biochemical parameters of fitness including hormonal status, a body impedance analysis, the grip strength, the amount of physical activity at home for 5 days via trackbands and anamnestic parameters were assessed. In addition, participants underwent an incremental symptom-limited cardiopulmonary exercise test (CPET) on a bicycle ergometer. Nineteen participants with KS aged 15.90 ± 4.12 years (range: 9.00 - 25.00) participated in the study. Pubertal status was Tanner 1 (n = 2), Tanner 2 - 4 (n = 7) and Tanner 5 (n = 10). Seven participants received testosterone replacement therapy. Mean BMI z-score was 0.45 ± 1.36 and mean fat mass was 22.93% ± 9.09. Grip strength was age-appropriate or above normal. 18 participants underwent CPET with subnormal results for maximum heart rate (z-score -2.84 ± 2.04); maximum workload (Wattmax; z score -1.28 ± 1.15) and maximum oxygen uptake per minute (z- score -2.25 ± 2.46). Eight participants (42.1%) met the criteria for chronotropic insufficiency (CI). Data from track-bands showed sedentary behavior for 81.15% ± 6.72 of the wear time. A substantial impairment of cardiopulmonary function can be detected in this group of boys to young adults with KS, including chronotropic insufficiency in 40%. The track-band data suggest a predominantly sedentary lifestyle, despite normal muscular strength as assessed via grip strength. Future studies need to investigate the cardiorespiratory system and its adaption to physical stress in a larger cohort and in more detail. It is feasible that the observed impairments contribute to the avoidance of sports in individuals with KS and may contribute to the development of obesity and the unfavorable metabolic phenotype.

Comparison of Cardiorespiratory Fitness of Chinese Tibetan Adolescents with Their Han Counterparts: A Cross-Sectional Retrospective Study.

Cardiorespiratory fitness (CRF) is a core element of healthy physical fitness. Foreign attention to CRF in adolescents at different altitudes is high, while less research has been conducted on Chinese adolescents. In order to compare the CRF of Chinese Tibetan adolescents with their Han counterparts born and raised at high altitude and Chinese Han adolescents at sea level. A total of 2748 participants, including Chinese Tibetan adolescents, Chinese Han adolescents born and raised at high altitudes, and Chinese Han adolescents at sea level aged 12-18 years old, were obtained using convenience sampling and random cluster sampling. The method of the 20 m shuttle run test (20 m SRT) test was used to derive VO2max by equation. One-way ANOVA and LSD methods were conducted, and effect sizes were calculated to compare the CRF of the three types of adolescents. Regression analysis was used to analyze the relationship between altitude and VO2max. The VO2max scores of Chinese Tibetan adolescents and Chinese Han adolescents at sea level were higher than Chinese Han adolescents born and raised at high altitudes. For both boys and girls, the VO2max scores of Chinese Tibetan adolescents exceeded Chinese Han adolescents at sea level after the age of 16 years old. Regression analysis showed that altitude was inversely associated with VO2max. The pace of lung growth may distinguish Chinese Tibetan adolescents from Chinese Han adolescents born and raised at high altitudes. The results of the study suggest that we should focus on the changes in CRF in adolescents at different altitudes and should adopt different CRF interventions for adolescents at different altitudes.

The Relative Importance of Age at Peak Height Velocity and Fat Mass Index in High-Intensity Interval Training Effect on Cardiorespiratory Fitness in Adolescents: A Randomized Controlled Trial.

Background: This study aimed to evaluate the role of biological age in the relationship between preintervention fat mass and cardiorespiratory fitness effects (CRF) after High-Intensity Interval Training (HIIT) intervention in adolescents. Methods: A total of 141 boys and girls (16 years) were examined as control (CG) and experimental (EG) groups that conducted a 10-week HIIT implemented in physical education. Measurements: body height, body weight, fat mass index (FMI), CRF (Harvard Step Test). Predicted age at peak height velocity (APHV) was calculated. Pathway analyses were conducted to identify the influences of the measured variables. Results: APHV harmed the level of ΔFI (fitness index) (β = −0.270; p = 0.035), while HIIT had a positive effect on changes in ΔFI (β = 0.246; p = 0.002). Sex affected the changes in CRF (β = 0.344; p = 0.011). Two models were designed respective to sex. The effect of the APHV on ΔFI in girls was close to significant (p = 0.053) but was non-significant in boys (p = 0.311). Changes in CRF in girls were positively and close to significance (p < 0.100) affected by FMIbaseline. Conclusion: HIIT is an effective way of exerting positive changes in CRF in adolescents, which is greater in boys than girls. APHV plays a role only in girls. The HIIT should be tailored to girls depending on their maturity status.

Cardiovascular health behavior and cardiorespiratory fitness in adolescents: a longitudinal study.

Cardiorespiratory fitness has been substantially associated with health status. However, longitudinal studies on cardiorespiratory fitness and ideal cardiovascular health behavior (ICHB) in adolescents are scarce. The aim of this study was to evaluate the longitudinal association between ICHB (at baseline) and cardiorespiratory fitness (at follow-up). This is a 2-year prospective analysis of 445 adolescents (232 girls) aged 12–18 years. The ICHB was developed by the American Heart Association as meeting the ideal health behaviors for a healthy diet, physical activity, smoking status, and body mass index. ANCOVAS adjusted by age, sex, pubertal stage, socioeconomic status, and cardiorespiratory fitness showed that the higher the number of ICHB metrics accumulated at baseline (from 1 to 4), the higher the cardiorespiratory fitness levels over a 2-year period (p = 0.038). In logistic regressions, after adjusting for potential confounders, the odds ratios for having high cardiorespiratory fitness at follow-up was 4.9 (95% CI, 1.2–20.1, p = 0.02) for those who accumulated all four metrics of ICHB, when compared to those with 1 or less metrics of ICHB. In addition, the higher the number of ICHB metrics accumulated, the higher the likelihood of having a high cardiorespiratory fitness level over a 2-year period (p for trend = 0.01).Conclusion: We identified a significant association between ICBH and cardiorespiratory fitness in adolescents. Therefore, improving ICBH in adolescence is likely to benefit the cardiorespiratory fitness. What is Known:• Smoking status, body mass index, physical activity, and diet are associated to cardiorespiratory fitness in adulthood.• Lifestyle behaviors such as physical activity, smoking, body weight, and healthy diet are individually linked with cardiorespiratory fitness and, however, have not been examined jointly, as combined health behaviors.What is New:• Accumulation of cardiovascular health behavior metrics was positively associated with cardiorespiratory fitness at a 2-year follow-up, in adolescents.• Meeting all the four metrics of ideal cardiovascular health behavior seems important for healthy cardiorespiratory fitness during adolescence.

Intensity and Duration of Physical Activity and Cardiorespiratory Fitness.

There is no clear guidance on the intensity and duration of physical activity (PA) that adolescents require to maximise cardiorespiratory fitness (CRF). We aimed to determine the strength of associations between each PA intensity and CRF, independently of other intensities, and the PA duration at each intensity associated with maximal CRF. PA and CRF were assessed in 339 adolescents aged 13 to 14 years by wrist-worn accelerometers and 20-m shuttle runs, respectively. Partial regression modeling was used to construct residualized PA variables at each PA intensity that were uncorrelated with each other. Moving average models were optimally fitted to determine relationships between residualized PA variables and CRF. Threshold regression models determined the duration of PA above which CRF improvement was minimal. Greater vigorous PA (VPA) was associated with better CRF until about 20 minutes of daily VPA, when the relationship plateaued. Moderate and light PA, and sedentary time were not associated with CRF in partial models. Adolescents performing 14 (range 12-17) minutes of daily VPA had median CRF. Participants in the upper quartile of VPA had 1.03 z-scores higher CRF than those in the lowest quartile (95% confidence interval: 0.75 to 1.30). Our data suggest that 20 minutes of daily VPA may be best for maximizing CRF in adolescence. As moderate-to-vigorous PA guidelines can be satisfied by only undertaking moderate PA, with no apparent independent benefit, we suggest that future guidelines focus on VPA alone, simplifying public health messaging.

Análise da relação entre broncoespasmo induzido por exercício, aptidão cardiorrespiratória e nível de atividade física de adolescentes

ABSTRACT This study aims to verify the association between exercise-induced bronchospasm (EIB), cardiorespiratory fitness, and physical activity levels in adolescents. To do so, we evaluated 202 healthy adolescents aged from 13 to 18 years, out of which 94 (46.5%) were females and 108 (53.5%) males. Participants performed a bronchial challenge test in a treadmill (Master Super ATL, Inbramed®) to evaluate bronchial hyper-responsiveness; a spirometric test (Microquark, Cosmed®) to evaluate lung function; answered the Baecke’s Questionnaire of Habitual Physical Activity; and performed the progressive aerobic cardiovascular endurance run test. Data were analyzed using Spearman’s correlation, chi-square test, and odds ratio. The significance level adopted was p&lt;0.05. No statistically significant correlations were found between the decrease of the forced expiratory volume in the first second (FEV1), cardiorespiratory fitness, and physical activity levels. Likewise, the chi-squared test revealed no significant differences between classifications of cardiorespiratory fitness (low or adequate) and EIB (presence or absence) (χ2=0.155; p=0.694). Finally, odds ratio showed no increased chances of the presence of EIB in participants who presented low cardiorespiratory fitness (OR=1.130; CI: 0.616-2.073). We concluded that cardiorespiratory fitness and physical activity levels are not associated with the decrease of FEV1 and that there is no relation between the presence of EIB and the classification of cardiorespiratory fitness of adolescents.

Anthropometric indicators of body fat as discriminators of low levels of cardiorespiratory fitness in adolescents

PurposeTo evaluate the discriminatory power of anthropometric indicators of body fat (BF) for identifying low levels of cardiorespiratory fitness, as well as the association between cutoff points and low levels of cardiorespiratory fitness in adolescents. Design and methodsThis is a cross-sectional study involving 1132 students (age 14–19 years). The following anthropometric variables were measured according to international standards: body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), triceps skinfold thickness (TR), subscapular skinfold (SS), suprailiac skinfold (SI), sum of triceps and subscapular skinfolds (∑TR + SS), and sum of triceps, subscapular and suprailiac skinfolds (∑TR + SS + SI). The BF percentage was calculated using the equations of Lohman (1986) (%FL), Slaughter et al. (1988) (%FS), and Boileau et al. (1985) (%FB). ResultsExcept for TR, WC, WHtR and BMI, boys with values for the other anthropometric indicators (SS, SI, ∑TR + SS, ∑TR + SS + SI, %FL, %FS, %FB) above the cutoff point were more likely to have low levels of cardiorespiratory fitness. Girls with values for TR, ∑TR + SS, %FB and %FL above the cutoff points were more likely to have low levels of cardiorespiratory fitness. ConclusionsAnthropometric indicators had discriminatory power to identify low levels of cardiorespiratory fitness. Practice implicationsThe reported anthropometric indicators, indexes and equations can be used by healthcare professionals in clinical practice and by school teachers as a simple, fast and inexpensive alternative to identify low levels of cardiorespiratory fitness.

Decreased ventricular size and mass mediate the reduced exercise capacity in adolescents and adults born premature

BackgroundPremature birth is associated with lower levels of cardiorespiratory fitness (CRF) but the underlying mechanisms responsible remain unclear. This study assessed whether differences in cardiac morphology or function mediate differences in CRF among adolescents and young adults born preterm. MethodsAdolescents and young adults born moderately to extremely premature (gestational age ≤ 32 weeks or birth weight < 1500 g) and age-matched term born participants underwent resting cardiac MRI and maximal exercise testing. Mediation analysis assessed whether individual cardiovascular variables accounted for a significant proportion of the difference in maximal aerobic capacity between groups. ResultsIndividuals born preterm had lower VO2max than those born term (41.7 ± 8.6 v 47.5 ± 8.7, p < 0.01). Several variables differed between term and preterm born subjects, including systolic and diastolic blood pressure, mean pulmonary artery pressure, indexed left ventricular end-diastolic volume (LVEDVi), right ventricular end-diastolic volume (RVEDVi), LV mass (LVMi), LV stroke volume index (LVSVi), and LV strain (p < 0.05 for all). Of these variables, LVEDVi, RVEDVi, LVSVi, LVMi, and LV longitudinal strain were significantly related to VO2max (p < 0.05 for all). Significant portions of the difference in VO2max between term and preterm born subjects were mediated by LVEDVi (74.3%, p = 0.010), RVEDVi (50.6%, p = 0.016), and LVMi (43.0%, p = 0.036). ConclusionsLower levels of CRF in adolescents and young adults born preterm are mediated by differences in LVEDVi, RVEDVi, and LVMi. This may represent greater risk for long-term cardiac morbidity and mortality in preterm born individuals.

School time is associated with cardiorespiratory fitness in adolescents: The HELENA study

ABSTRACT We assessed the association between school time and physical fitness in adolescents. The study included 2,024 adolescents, aged 12.5–17.5 years, who participated in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. Health-related physical fitness components were assessed using the physical fitness tests battery. Cardiovascular risk was categorized using the sex-specific cut-offs for a healthy cardiorespiratory fitness level in adolescents proposed by FitnessGram®. School time was classified as short or long. Multivariate analysis accounted for confounding factors such age, sex, body mass index, time spent in moderate to vigorous physical activity, pubertal status, and parents’ educational level. Cardiorespiratory fitness was higher in adolescents with a long school time than in those with a short school time (42.0 ± 7.6 vs 40.7 ± 7.2 mL.kg–1.min–1, respectively; p < 0.05). The percentage of adolescents at cardiovascular risk in adulthood was higher in the short than in the long time group (45.2% vs 31.7%, respectively) (p < 0.05). These findings suggest that a long school day is associated with higher cardiorespiratory fitness in adolescents and that school time should be considered in interventions and health promotion strategies.

The Relationship Between Cognitive Performance and Cardiorespiratory Fitness in Adolescents

Background. Literature suggests cardiorespiratory fitness as a factor influencing cognitive improvement. The authors of the present study sought to investigate if cardiorespiratory fitness related to cognitive performance after an acute bout of game-based exercise of different intensities in adolescents.&#x0D; Methods. As many as 37 adolescents (24 girls and 13 boys, 15–16 years of age) were assigned to three groups: experimental group 1 (EX 1), experimental group 2 (EX 2), and control (CON) group. The experimental groups experienced different levels of exercise intensity (EX 1 – light intensity, EX 2 – vigorous intensity). The Shuttle Run Test was performed a week before the intervention and VO2peak was calculated. Symbol Digit Modalities Test (SDMT) was evaluated before and after the acute intervention. A 2 x 3 repeated-measures ANOVA was used to analyze the SDMT and Pearson’s correlation coefficient was used to estimate the relationship between the cognitive performance (SDMT) and cardiorespiratory fitness (VO2peak).&#x0D; Results. Comparing the SDMT scores before and after the intervention, there were no differences found between the three groups. Neither in any of the experimental groups nor in the control group was a relationship between the SDMT score and VO2peak observed.&#x0D; Conclusion. Acute game-based exercise intervention did not prove to improve cognitive performance effectively. The authors of the present paper did not confirm the relationship between cardiorespiratory fitness and cognitive performance in adolescents.&#x0D; Keywords: exercise, cognitive performance, cardiorespiratory fitness.

Cardiorespiratory fitness in adolescents before and after the COVID-19 confinement: a prospective cohort study.

Long periods of free-movement restrictions may negatively affect cardiorespiratory fitness and health. The present study investigated changes after the COVID-19 confinement in maximal oxygen intake (VO2 max) levels in a sample of 89 Spanish school children aged 12 and 14 years at baseline (49.8% girls). The 20-m shuttle run test served to estimate VO2 max before and after the COVID-19 confinement. Paired t-tests estimated an overall difference of − 0.5 ml.kg−1.min−1 (SD 0.3) (p = 0.12), whereas the highest significant reductions were observed for girls aged 14 years (− 1.5 ml.kg−1.min−1 (SD 0.6) (p < 0.05)). Boys aged 14 years showed a slight increase (0.4 ml.kg−1.min−1 (SD 0.5) (p = 0.44)), whereas boys aged 12 years presented an important decrease (− 1.2 ml.kg−1.min−1 (SD 0.7) (p = 0.14)). Healthy Fitness Zone (HFZ) levels also experienced a decrease of − 3.4% as regards baseline levels over the examined period. All the examined subgroups showed lower levels in relation to a normal VO2 max rate development, although girls aged 14 and boys aged 12 years accounted for the highest part.Conclusion: The results indicate that COVID-19 confinement might delay the normal development of VO2 max in adolescents. Strategies to tackle this concerning decline are warranted. What is Known:• First study analyzing cardiorespiratory fitness levels in teenagers after COVID-19 confinement.What is New:• Important delay in maximal oxygen intake identified in a sample of Spanish teenagers.• These results should be considered to develop strategies of a more active lifestyle in teenagers during and after confinements.

C-reactive protein is inversely and independently associated with maximal oxygen uptake in adolescents with obesity

The purposes of this study were: 1) investigate whether different markers of infl ammation (CRP and TNF-alpha) are correlated to cardiorespiratory fi tness in adolescents with obesity; 2) examine the association of these variables when adjusted by parameters of body composition. Were selected 57 individuals, 34 girls and 23 boys, with 16.4±1.56 years and body mass index 36.0±4.3 kg/m2. Anthropometric measurements (weight, height and abdominal circunference) and body composition (BMI, visceral fat, body fat) were assessment. Body composition was estimated by analyzer of tetrapolar bioelectrical impedance. Obesity was defi ned as BMI&gt;95th percentile of the curve proposed by the Center for Diseases Control. Plasma TNF-alpha was measured by a quantitative two-site high-sensitivity enzyme immunoassay and CRP was measured by high-sensitivityimmunoturbidimetric assay. Graded maximal exercise testing was performed to obtain the maximum oxygen consumption (VO2max) and velocity associated with the VO2max (vVO2max). Signifi cant correlations of CRP with VO2max and vVO2max were found (r=-0.40 and r=-0,36, respectively). No correlations were observed between TNF-alpha and VO2max e vVO2max. CRP was associated to the VO2max and vVO2max independently of measurements of body composition. The CRP was independently and inversely associated with direct measurement of VO2max and the indirect variable of cardiorespiratory fitness vVO2max, in obese adolescents, even after adjustments in body composition, a potential confounding factor. No association was found between TNF-alpha and the parameters of cardiorespiratory fitness.