Association Of Cardiorespiratory Fitness Research Articles

Associations of Cardiorespiratory Fitness and Adiposity With Arterial Stiffness and Arterial Dilatation Capacity in Response to a Bout of Exercise in Children.

Purpose: To investigate the associations of directly measured peak oxygen uptake ( ) and body fat percentage (BF%) with arterial stiffness and arterial dilatation capacity in children. Methods: Findings are based on 329 children (177 boys and 152 girls) aged 8-11 years. was assessed by a maximal cardiopulmonary exercise test on a cycle ergometer and scaled by lean body mass (LM). BF% and LM were measured by bioelectrical impedance. Stiffness index (measure of arterial stiffness) and change in reflection index (ΔRI, measure of arterial dilatation capacity) were assessed by pulse contour analysis. Data were analyzed by linear regression models. Results: was positively associated with ΔRI in boys adjusted for age and BF% (β = 0.169, P = .03). Further adjustments for systolic blood pressure, heart rate, and the study group had no effect on this association, but additional adjustment for clinical puberty attenuated it (β = 0.171, P = .07). BF% was inversely related to ΔRI in boys adjusted for age and (β = -0.171, P = .03). or BF% was not associated with ΔRI in girls or with stiffness index in either boys or girls. Conclusion: Increasing cardiorespiratory fitness and decreasing adiposity may improve arterial health in childhood, especially among boys.

Association of cardiorespiratory fitness with arterial stiffness and peripheral and central blood pressure in resistant hypertension patients

BackgroundThe relationship between arterial stiffness, blood pressure (BP) and cardiorespiratory fitness (CRF) has been studied in healthy populations and cardiovascular patients, since all of which proved to be independent predictors of all-cause mortality. We aimed to investigate the association of CRF with arterial stiffness and peripheral and central hemodynamics, in patients with resistant hypertension (RT).MethodsIn this cross-sectional study, 30 patients (13 men, 17 women; age, 57.7 ± 8.1 years; weight, 79.2 ± 11.6 kg; body mass index, 29.7 ± 4.0 kg/m2) with resistant hypertension were recruited in the Hospital Infante D. Pedro (Aveiro) and Hospital Pedro Hispano (Matosinhos). Outcome measures included CRF (VO2peak), peripheral and central BP, and carotid-femoral pulse wave velocity (cf-PWV). Correlation analysis was conducted to assess the association between variables.ResultsA significant negative correlation was found between VO2peak (33.7 ± 6.2 mLO2/kg/min) and central (141.0 ± 21.3 mmHg; r = −0.395, p = 0.031) and peripheral systolic BP (148.4 ± 21.3 mmHg; r = −0.363, p = 0.049). VO2 peak was also correlated with pulse pressure (PP) amplification ratio (1.2 ± 0.1 mmHg; r = 0.361, p = 0.050). The association with central systolic BP (r = −0.403, p = 0.035) and PP amplification ratio (r = 0.408, p = 0.033) remained significant after adjusted for age. VO2 peak showed no correlation with PWV (9.4 ± 2.9 m/s; r = −0.075, p = 0.694) and peripheral (88.1 ± 12.2 mmHg; r = −0.138 p = 0.467) and central diastolic BP (88.5 ± 12.7 mmHg; r = −0.133, p = 0.483).ConclusionThis study confirms the inverse relationship between CRF and central systolic BP and PP amplification ratio in RH patients, regardless of age.

Fitness, cortical thickness and surface area in overweight/obese children: The mediating role of body composition and relationship with intelligence

Cortical thickness and surface area are thought to be genetically unrelated and shaped by independent neurobiological events suggesting that they should be considered separately in morphometric analyses. Although the developmental trajectories of cortical thickness and surface area may differ across brain regions and ages, there is no consensus regarding the relationships of physical fitness with cortical thickness and surface area as well as for its subsequent influence on intelligence. Thus, this study examines: (i) the associations of physical fitness components (i.e., cardiorespiratory fitness, speed-agility and muscular fitness) with overall and regional cortical thickness and surface area; (ii) whether body composition indicators (i.e., body mass index, fat-free mass index and fat mass index) mediate these associations; and (iii) the association of physical fitness and cortical thickness with intelligence in overweight/obese children. A total of 101 overweight/obese children aged 8–11 years were recruited in Granada, Spain. The physical fitness components were assessed following the ALPHA health-related fitness test battery. T1-weighted images were acquired with a 3.0 Tesla Siemens Magnetom Tim Trio system. We used FreeSurfer software version 5.3.0 to assess cortical thickness (mm) and surface area (mm2). The main results showed that cardiorespiratory fitness and speed-agility were related to overall cortical thickness (β = 0.321 and β = 0.302, respectively; both P < 0.05), and in turn, cortical thickness was associated with higher intelligence (β = 0.198, P < 0.05). Muscular fitness was not related to overall cortical thickness. None of the three physical fitness components were related to surface area (p > 0.05). The associations of cardiorespiratory fitness and speed-agility with overall cortical thickness were mediated by fat mass index (56.86% & 62.28%, respectively). In conclusion, cardiorespiratory fitness and speed-agility, but not muscular fitness, are associated with overall cortical thickness, and in turn, thicker brain cortex is associated with higher intelligence in overweight/obese children. Yet, none of the three physical fitness components were related to surface area. Importantly, adiposity may hinder the benefits of cardiorespiratory fitness and speed-agility on cortical thickness. Understanding individual differences in brain morphology may have important implications for educators and policy makers who aim to determine policies and interventions to maximize academic learning and occupational success later in life.

Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing

Adverse cardiovascular findings associated with habitual vigorous exercise have raised new questions regarding the benefits of exercise and fitness. To assess the association of all-cause mortality and cardiorespiratory fitness in patients undergoing exercise treadmill testing. This retrospective cohort study enrolled patients at a tertiary care academic medical center from January 1, 1991, to December 31, 2014, with a median follow-up of 8.4 years. Data analysis was performed from April 19 to July 17, 2018. Consecutive adult patients referred for symptom-limited exercise treadmill testing were stratified by age- and sex-matched cardiorespiratory fitness into performance groups: low (<25th percentile), below average (25th-49th percentile), above average (50th-74th percentile), high (75th-97.6th percentile), and elite (≥97.7th percentile). Cardiorespiratory fitness, as quantified by peak estimated metabolic equivalents on treadmill testing. All-cause mortality. The study population included 122 007 patients (mean [SD] age, 53.4 [12.6] years; 72 173 [59.2%] male). Death occurred in 13 637 patients during 1.1 million person-years of observation. Risk-adjusted all-cause mortality was inversely proportional to cardiorespiratory fitness and was lowest in elite performers (elite vs low: adjusted hazard ratio [HR], 0.20; 95% CI, 0.16-0.24; P < .001; elite vs high: adjusted HR, 0.77; 95% CI, 0.63-0.95; P = .02). The increase in all-cause mortality associated with reduced cardiorespiratory fitness (low vs elite: adjusted HR, 5.04; 95% CI, 4.10-6.20; P < .001; below average vs above average: adjusted HR, 1.41; 95% CI, 1.34-1.49; P < .001) was comparable to or greater than traditional clinical risk factors (coronary artery disease: adjusted HR, 1.29; 95% CI, 1.24-1.35; P < .001; smoking: adjusted HR, 1.41; 95% CI, 1.36-1.46; P < .001; diabetes: adjusted HR, 1.40; 95% CI, 1.34-1.46; P < .001). In subgroup analysis, the benefit of elite over high performance was present in patients 70 years or older (adjusted HR, 0.71; 95% CI, 0.52-0.98; P = .04) and patients with hypertension (adjusted HR, 0.70; 95% CI, 0.50-0.99; P = .05). Extreme cardiorespiratory fitness (≥2 SDs above the mean for age and sex) was associated with the lowest risk-adjusted all-cause mortality compared with all other performance groups. Cardiorespiratory fitness is inversely associated with long-term mortality with no observed upper limit of benefit. Extremely high aerobic fitness was associated with the greatest survival and was associated with benefit in older patients and those with hypertension. Cardiorespiratory fitness is a modifiable indicator of long-term mortality, and health care professionals should encourage patients to achieve and maintain high levels of fitness.

The association of cardiorespiratory fitness, body mass index, and age with testosterone levels at screening of healthy men undergoing preventive medical examinations: The Cooper Center Longitudinal Study

BackgroundCurrently, exogenous hormone replacement is used in many men with hypogonadism without clear organic cause. This study examines the contribution of modifiable health behaviors, i.e., physical activity and weight control, to the maintenance of testosterone levels with aging. MethodsIn a cross-sectional study of 2994 healthy men aged 50–79 years examined at a preventive medicine clinic from January 2012 to March 2016, screening morning total testosterone levels were measured and categorized as low (<250 ng/dL), low normal (250–399 ng/dL), and normal (>400 ng/dL). Cardiorespiratory fitness (fitness) was estimated from a maximal exercise treadmill test. Multiple logistic regression models were used to test the associations between low testosterone levels and age, body mass index (BMI), and fitness. FindingsMean testosterone levels were in the normal range for each age group (50–59, 60–69, and 70–79). There was a similar prevalence of low testosterone in each age group (11·3%, 10%, and 10·5%, respectively). The prevalence of low testosterone was positively associated with BMI and negatively associated with fitness but was not associated with age. InterpretationThis study found no evidence that low testosterone is an inevitable consequence of aging. Maintenance of healthy weight and fitness may help maintain normal testosterone levels.

Association of cardiorespiratory fitness with retinal vessel diameters as a biomarker of cardiovascular risk

ObjectiveWe aimed to investigate the association of retinal microvascular health with cardiorespiratory fitness (VO2peak) and cardiovascular risk factors. MethodsIn a population of 260 obesity-enriched participants we investigated the association of retinal vessel diameters with cardiorespiratory fitness (CRF), body mass index (BMI) and blood pressure (BP). Retinal vessel imaging was performed by use of a fundus camera and a semi-automated processing software, calculating the central retinal arteriolar (CRAE) and venular equivalent (CRVE) as well as the arteriolar-to-venular diameter ratio (AVR). ResultsParticipants had a mean age of 45.8 ± 12.5 years and a BMI of 35.8 ± 6.8 kg/m2. 45% of patients were diagnosed with hypertension, 26% with diabetes and 30% with dyslipidemia. Increasing VO2peak was independently associated with lower CRVE (β = −0.600; CI −1.141, −0.060; p = 0.030). Higher BMI and mean arterial pressure were independently associated with narrower CRAE (β = −0.492; CI −0.909, −0.076; p = 0.021 and β = −0.268; CI −0.471, −0.066; p = 0.009, respectively) and lower AVR (β = −0.002; CI −0.003, −0.000; p = 0.026 and β = −0.001; CI −0.002, −0.000; p = 0.001, respectively). ConclusionsHigher cardiorespiratory fitness is associated with beneficial retinal microvascular health. Higher BMI and BP were associated with an impairment of retinal microvascular health. Exercise is known for its potential to improve body composition and reduce BP but may also prove to be an efficient therapy to counteract small vessel disease in cardiometabolic disease.

Associations of Cardiorespiratory Fitness and Percent Body Fat with Health-Related Quality of Life in Elderly

Associations of Cardiorespiratory Fitness and Percent Body Fat with Health-Related Quality of Life in Elderly

Abstract P302: Ethnic Difference of Cardiorespiratory Fitness and Related to Factors in Young Adults: The Nhanes 1999-2004

Background: Cardiorespiratory fitness is a distinct health characteristic that relates to the ability to perform physical activity. Higher cardiorespiratory fitness was reported to have reverse relationship with overall mortality and morbidity rates due to various chronic disease. The assessment of cardiorespiratory fitness was measured by maximal oxygen uptake (VO2max; mL/kg/minute) on a submaximal treadmill test. This study was aimed to examine cardiorespiratory fitness among U.S. adults 20-49 years of age, to describe the distribution of cardiorespiratory fitness and cardiovascular risk factors depends on different ethnicity for without physical limitations or indications of cardiovascular disease. Method: Data from the 1999-2004, National Health and Nutrition Examination Survey were used to describe the distribution of cardiorespiratory fitness for adults 20-49 years of age. 8324 out of 31126 subjects have valid values of cardiopulmonary fitness in the dataset with 5391 in low category of cardiorespiratory fitness (VO 2 max &lt; 27), 2606 in medium category (37.1 &gt; VO 2 max ≥27) and 327 in high category (37.1 ≥ VO 2 max). The risk factors for cardiopulmonary fitness was assessed by using logistic regression after adjusting all cardiovascular risk factors. All data were analyzed using SAS Ver. 9.4. Result: Overall, there is no significant association of cardiorespiratory fitness with ethnicity ( P =0.08). 65.9% of study population was male in all races. Among, non-Hispanic whites, those with 25 m 2 /kg &gt; BMI had better cardiorespiratory fitness (more than 37.1 mL/kg/minute) than those with BMI ≥ 35 [Odds ratio (OR): 0.496, Confidence Interval (CI): 0.258-0.957]. A similar pattern was observed for Mexican Americans. Non-Hispanic black with 25 m 2 /kg &gt; BMI had better cardiorespiratory fitness than ones with BMI ≥ 35 m 2 /kg [OR:0.137, CI:0.059-0.318], 35 m 2 /kg &gt; BMI≥30 m 2 /kg [OR:0.269, CI:0.124-0.583], 30 m 2 /kg &gt; BMI≥25 m 2 /kg [OR: 0.241,0.123-0.318]. Non-Hispanic white with higher diastolic blood pressure over 90 mmHg had tendency to have lower cardiorespiratory fitness. Among metabolic panel, only Mexican American with LDL&lt;100 mg/dl has higher cardiorespiratory fitness [OR:0.559, CI:0.319-0.981]. Discussion: Our findings on cardiorespiratory fitness level among non-Hispanic blacks, non-Hispanic whites and Mexican Americans are similar to previously reported studies, however, non-Hispanic black had different risk factors related to cardiorespiratory fitness, especially significant benefit from lower BMI less than 25 m 2 /kg since other ethnicities with BMI less than 25 m 2 /kg had benefit only compared to BMI&gt; 35 m 2 /kg. These results can be used to improve cardiorespiratory fitness level for future population based on ethnicities. The different risk factors in fitness status can also be used to develop health policies and targeted educational campaigns.

The association of cardiorespiratory fitness with cardiometabolic factors, markers of inflammation, and endothelial dysfunction in Latino youth: findings from the Hispanic Community Children’s Health Study/Study of Latino Youth

PurposeTo evaluate the relationship of cardiorespiratory fitness (CRF) with cardiovascular disease risk factors and a biomarker of endothelial dysfunction (e-selectin) among Hispanic/Latino youth. MethodsThe study included 1380 Hispanic/Latino youths (8–16 years old) from the Hispanic Community Children’s Health Study/Study of Latino Youth that enrolled from four cities (Bronx, Chicago, Miami, and San Diego). CRF was assessed by a 3-minute step test that uses postexercise heart rate to estimate maximal oxygen uptake. Regression models assessed differences in cardiometabolic markers across quartiles of CRF, adjusting for potential confounders. ResultsCRF was higher among boys (mean: 57.6 mL per kg/min, 95% confidence interval, 56.8–58.4) compared to girls (mean: 54.7 mL per kg/min, 95% confidence interval, 53.9–55.5). Higher levels of CRF were associated with more favorable levels of cardiometabolic, inflammation, and endothelial dysfunction factors (P-values <.001) and independently of physical activity and sedentary time. Compared to the lowest quartile of CRF, the odds of having greater than or equal to two cardiovascular disease risk factors was lower at higher quartiles of CRF, after adjustment for potential confounders. ConclusionsAmong Hispanic/Latino youth, CRF appears to be a strong protective factor for endothelial dysfunction and cardiometabolic risk factors. Strategies to improve CRF may be a useful approach for improving cardiovascular health in youth.

Association of Cardiorespiratory Fitness, Visceral Fat and Weight Cycling History in Pre-menopausal Women.

Weight cycling (WC), or repeated bouts of intentional weight fluctuations are common among overweight and obese women and have been linked to various cardiometabolic health risks such as visceral fat (VF) accumulation. Cardiorespiratory fitness (CRF), independent of weight loss, is a known counter measure to health risks and VF. Although, WC has been positively associated with increases in VF, this association may be confounded by age and/or physical activity status. PURPOSE: This cross sectional study explored the association of multiple factors (i.e., AGE, WC and CRF) on VF and investigated WC as a potential moderator on the relationship between CRF and VF among pre-menopausal women. METHODS: 41 overweight and obese (BMI = 30.4 ± 6.2 kg/M2) pre-menopausal (age = 31.0 ± 5.6 yrs) women were assessed. Dichotomous WC groups were established from the number of self-reported WC bouts and total weight lost per bout. WC (n = 19) was defined as ≥ 3 cycles of ≥ 10 lb; and Non-WC (n = 22) was defined as not meeting WC definition. Additionally, a weight cycling index (WCI) was constructed to form a continuous variable. WC due to pregnancy and illness were excluded from the totals. CRF was determined with indirect calorimetry using a cycle ergometer protocol to peak VO2, and VF volume (cm3) was assessed with CoreScan software (iDXA, GE Lunar). Correlation and multiple regression analysis were used to examine the relationship between VF and potential predictors, and possible moderator effects. RESULTS: Significant (p < .001) differences between WC vs. Non-WC groups were found for AGE (33.1 + 3.7 vs. 29.3 + 6.4 yr); BMI (34.6.1 + 5.7 vs. 26.7 + 3.8 kg/M2); VF (1257.2 + 1033.0 vs. 426.6 + 547.0 cm3); and CRF (24.1 + 5.7 vs. 31.0 + 6.5 ml/kg/min). The strongest association was found between CRF and VF (R = -0.718, p < .001). The regression model with four factors (AGE, WCI, CRF, WC x CRF) was significant (R2 = .570, p ≤ .001); however, only CRF significantly predicted VF (p ≤ .001). The WC x CRF interaction was not significant (p = .150) with a [INCREMENT]R2 = .026, predicting only 2% of VF. Thus, no moderator effect was detected. CONCLUSION: These findings suggest the relationship between CRF and VF was independent of WC status and that CRF was the most influential factor predicting VF among overweight and obese pre-menopausal women with a history of weight cycling.

The associations of cardiorespiratory fitness, adiposity and sports participation with arterial stiffness in youth with chronic diseases or physical disabilities.

BackgroundThe evidence on the associations of cardiorespiratory fitness, body adiposity and sports participation with arterial stiffness in children and adolescents with chronic diseases or physical disabilities is limited.MethodsAltogether 140 children and adolescents with chronic diseases or physical disabilities participated in this cross-sectional study. Cardiorespiratory fitness was assessed using maximal exercise test with respiratory gas analyses either using shuttle run, shuttle ride, or cycle ergometer test. Cardiorespiratory fitness was defined as peak oxygen uptake by body weight or fat-free mass. Body adiposity was assessed using waist circumference, body mass index standard deviation score and body fat percentage. Sports participation was assessed by a questionnaire. Aortic pulse wave velocity and augmentation index were assessed by a non-invasive oscillometric tonometry device.ResultsPeak oxygen uptake/body weight (standardised regression coefficient β −0.222, 95% confidence interval (CI) −0.386 to −0.059, P = 0.002) and peak oxygen uptake/fat-free mass (β −0.173, 95% CI −0.329 to −0.017, P = 0.030) were inversely and waist circumference directly (β 0.245, 95% CI 0.093 to 0.414, P = 0.002) associated with aortic pulse wave velocity. However, the associations of the measures of cardiorespiratory fitness with aortic pulse wave velocity were attenuated after further adjustment for waist circumference. A higher waist circumference (β −0.215, 95% CI −0.381 to −0.049, P = 0.012) and a higher body mass index standard deviation score (β 0.218, 95% CI −0.382 to −0.054, P = 0.010) were related to lower augmentation index.ConclusionsPoor cardiorespiratory fitness and higher waist circumference were associated with increased arterial stiffness in children and adolescents with chronic diseases and physical disabilities. The association between cardiorespiratory fitness and arterial stiffness was partly explained by waist circumference.

Abstract P139: The Association of Cardiorespiratory Fitness With Cardiometabolic Risk Factors and Markers of Endothelial Function in the Study of Latino Youth (SOL Youth)

Background: Adult cardiorespiratory fitness (CRF) is associated with lower risk of cardiovascular disease and mortality. However, there is scarce information in youth about the role of CRF in subclinical measures of CVD, such as endothelial function. In this study we tested associations of cardiometabolic factors (CMF) and biomarkers of endothelial function (e-selectin; PAI-1). Methods: We included 1,380 participants (699 girls and 681 boys) aged 8-16 years from SOL Youth. CRF was assessed by a step test and VO2 max was estimated. CMF included fasting glucose, lipids, blood pressure. Inflammatory markers included hs-CRP and adiponectin. Associations of CRF with e-selectin and PAI-1 were assessed with multiple linear regression models, adjusting for potential confounders: actigraphy derived physical activity (PA) and sedentary time (SED), adiposity, and socio-demographic factors. Odds ratios were derived for the association of CRF and having ≥3 CVD risk factors (RF)(defined by elevated age/sex appropriate BP, lipids, glucose, and obesity), adjusted for confounders. Analyses accounted for complex survey design. Results: Boys and US-born youth were more likely to have higher CRF. CRF was positively correlated with PA (r=.23, p&lt;.0001) but inversely correlated with SED (r=-.10, p=.001), BMIz-score (r=-.37, p&lt;.0001), waist circumference (WC)(r=-.38, p&lt;.0001), and %body fat (r=-.43, p&lt;.0001). In multivariate models adjusting for socio-demographic factors, PA and SED (model 1), CRF was strongly and inversely associated with markers of endothelial function, inflammation, and CMF, which were attenuated when adjusting for WC (model 2)(Table 1). The odds of having ≥3 CVD RF was significantly lower at highest quartiles of fitness (ORs Q2=.47, Q3=.68, Q4=.35, p-trend=.001) after adjusting for confounders and WC. Conclusions: Among Latino youth, CRF appears to be a strong protective factor for endothelial dysfunction and CMF. Strategies to improve CRF may be a useful approach for improving cardiovascular health in youth.

Controversies in the association of cardiorespiratory fitness and arterial stiffness in children and adolescents.

The relationship between cardiorespiratory fitness and arterial compliance in children and adolescents remains controversial. The aim of this study was to assess this association with a quantitative approach. A total of 646 healthy children and adolescents (316 females, age 13.9±2.1 years) were cross-sectionally investigated in seven school settings in and around Munich for their cardiorespiratory fitness and demographic, anthropometric and hemodynamic parameters. Surrogates of arterial stiffness, such as pulse wave velocity (PWV), Augmentation Index normalized to a heart rate of 75 (AI@75), and peripheral and central systolic blood pressures were measured in a supine position using the oscillometric Mobil-O-Graph. Cardiopulmonary fitness was measured by 6-min indoor run tests. After correction for age, sex, body weight, body height, heart rate and mean arterial pressure, controversial findings were produced. PWV increased with higher cardiorespiratory fitness (Beta=0.173; P<0.001), which represented an unfavorable relationship, whereas AI@75 declined with higher cardiorespiratory fitness (Beta=-0.106; P=0.025). Therefore, in contrast to PWV, higher cardiorespiratory fitness seems beneficial for AI@75. The third surrogate of arterial stiffness, central systolic blood pressure, showed no association with cardiorespiratory fitness (Beta=0.066; P=0.052). These controversial outcomes remain almost unchanged when the boys and girls were analyzed separately. Different surrogates of arterial stiffness have different relationships with cardiorespiratory fitness in children and adolescents after correcting for multiple confounders. More research is needed in this field to understand the functioning of the juvenile vessels, and measurements and methodological approaches should be reconsidered.

Association of cardiorespiratory fitness and adiposity with inflammatory biomarkers in young adults.

Cardiorespiratory fitness (fitness) has been inversely associated with inflammation, but whether the association is attributed to fitness itself or lower levels of adiposity remains uncertain in young adults. The purpose of this study was to determine the association of fitness and adiposity with inflammation in young adults. A cross-sectional study was conducted with 88 participants aged 20-34 years. Fitness was assessed by a submaximal treadmill walking test. Adiposity was assessed by body mass index (BMI) and waist circumference (WC). Inflammation was measured by plasma C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) levels using immunoassays. Biological data were log10 transformed. A separate multiple regression analysis was conducted with each inflammatory biomarker as a dependent variable. Covariates (sex, oral contraceptive use, and education level) were adjusted. Fitness was inversely associated with log10 CRP after adjustment for covariates but not after adjusting for BMI or WC. Fitness was inversely associated with log10 IL-6 after adjustment for WC and covariates (β = -0.341, P = .049) but not after adjusting for BMI. Fitness × WC interaction (partial eta2 = 0.056, P = .033) indicated that high fitness was more strongly associated with low log10 IL-6 in young adults with high WC than those with low WC. Although adiposity has a stronger association than fitness with CRP and IL-6, higher levels of fitness could be essential for maintaining low levels of IL-6, especially in the presence of high levels of central adiposity.

Obesity, Cardiorespiratory Fitness, and Self-Reported Sleep Patterns in Chilean School-Aged Children

The aims were to examine the association of sleep patterns with being overweight or obese and to analyze the association of cardiorespiratory fitness (CRF) with sleep patterns in children. The study involved 395 schoolchildren (12–13 years old). Sleep patterns were assessed with the Sleep Self-Report (SSR) questionnaire, grouped into four subscales: sleep quality, sleep-related anxiety, bedtime refusal, and sleep routines. CRF was predicted by the 20-m shuttle-run test. Logistic regression models showed that sleep-related anxiety problems predicted being overweight or obese in both sexes, and sleep quality problems predicted being overweight or obese in girls. Also, girls who had better CRF levels were less susceptible to sleep-related anxiety problems. Studies are required to determine if increasing CRF could be a possible strategy for improving sleep quality.

Associations of cardiorespiratory fitness, physical activity, and adiposity with arterial stiffness in children.

Associations of cardiorespiratory fitness (CRF), physical activity (PA), sedentary behavior, and body fat percentage (BF%) with arterial stiffness and dilation capacity were investigated in 160 prepubertal children (83 girls) 6-8 years of age. We assessed CRF (watts/lean mass) by maximal cycle ergometer exercise test, total PA, structured exercise, unstructured PA, commuting to and from school, recess PA and total and screen-based sedentary behavior by questionnaire, BF% using dual-energy X-ray absorptiometry, and arterial stiffness and dilation capacity using pulse contour analysis. Data were adjusted for sex and age. Poorer CRF (standardized regression coefficient β = -0.297, P < 0.001), lower unstructured PA (β = -0.162, P = 0.042), and higher BF% (β = 0.176, P = 0.044) were related to higher arterial stiffness. When CRF, unstructured PA, and BF% were in the same model, only CRF was associated with arterial stiffness (β = -0.246, P = 0.006). Poorer CRF was also related to lower arterial dilation capacity (β = 0.316, P < 0.001). Children with low CRF (< median) and high BF% (≥ median; P = 0.002), low CRF and low unstructured PA (< median; P = 0.006) or children with low unstructured PA and high BF% (P = 0.005) had higher arterial stiffness than children in the opposite halves of these variables. Poor CRF was independently associated with increased arterial stiffness and impaired arterial dilation capacity among children.

The association of cardiorespiratory fitness to health independent of adiposity depends upon its expression

Background: The strong relation between cardiorespiratory fitness (CRF) and adiposity renders their independent associations to metabolic risk factors difficult to ascertain.Aim: To determine the associations of CRF and CRF relative to fat-free mass (CRFFFM) to total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, glucose, insulin and homeostasis model assessment (HOMA) and distinguish these relations from the association to adiposity.Subjects and methods: Anthropometrics, body fat percentage (%Fat) and fat-free mass (from dual energy X-ray absorptiometry) were measured in 127 (66 females) 17 and 23 year-olds. CRF from a maximal workload on a graded bicycle test and fasting blood samples were obtained.Results: CRF was significantly related to total cholesterol, triglycerides, insulin and HOMA (r = −0.24 to −0.49, p < 0.03), as were all adiposity measures (r = 0.21–0.53, p < 0.05). Correcting CRF for %Fat rendered the relation to metabolic risk factors non-significant (p = 0.09–0.21); however, CRFFFM was significantly related to the metabolic risk factors (r = −0.25 to −0.32, p < 0.02).Conclusions: CRFFFM, where adiposity has been removed, is associated with metabolic risk factors, whereas CRF, which is related to adiposity, is not after adjustment for fatness. Previously, independent effects of CRF on health may have been underestimated by using an expression of CRF strongly related to the adiposity measures.

Abstract P283: Association of Cardiorespiratory Fitness and Adiposity with Inflammatory Biomarkers in Young Adults

Introduction: Low grade systemic inflammation plays a key role in the pathogenesis of atherosclerosis. There is evidence that higher cardiorespiratory fitness (CRF) is associated with lower levels of inflammatory biomarkers. However, it remains uncertain whether the negative association between CRF and inflammatory biomarkers is due to CRF itself or results from lower levels of adiposity. Moreover, adiposity, including central adiposity, has not been examined as a moderator of the association between CRF and inflammatory biomarkers in young adults. Hypotheses: 1. Higher level of CRF will be associated with lower levels of inflammatory biomarkers after adjusting for levels of adiposity and confounders. 2. Adjusting for confounders, there will be a significant interaction effect between adiposity (BMI, waist circumference (WC)) and CRF in relation to inflammatory biomarker levels. Methods: A cross-sectional study was conducted in Houston, TX. A sample of 88 asymptomatic young adults aged 20-34 years without diagnosed diseases was accessed. CRF was assessed by a submaximal treadmill walking test. Adiposity was measured using BMI and WC. The inflammatory biomarkers (hs-CRP, IL-6 and TNF-α) were assayed and were log 10 -transformed. A separate multiple regression analysis was conducted with each of inflammatory biomarker as dependent variables for hypothesis one. Analysis of covariance was used for hypothesis two. Confounding variables tested were sex, ethnicity, oral contraceptive use, and education level. Results: Hypothesis 1: CRF was not associated with log 10 hs-CRP after adjustment for BMI (or WC) and confounders. CRF was not associated with log 10 IL-6 after adjustment for BMI and confounders. However, CRF was negatively associated with log 10 IL-6 after adjustment for WC and confounders (Model adjusted R 2 =.273, p &lt; .0001; β = -.341, t = -1.995, p =.049). Hypothesis 2: CRF х BMI (or WC) interaction was not associated with log 10 hs-CRP after adjustment for confounders. CRF х BMI interaction was not associated with log 10 IL-6 after adjustment for confounders. However, CRF х WC interaction was negatively associated with log 10 IL-6 after adjustment for confounders (Model adjusted R 2 = .258, p &lt; .0001; partial eta 2 =.056, F = 4.730, p = .033). There were no associations of CRF, adiposity, and log 10 TNF-α. Conclusions: In young adults, higher level of CRF is associated with lower level of IL-6 after adjustment for central adiposity and confounders. Further, there is a significant interaction between CRF and WC in relation to IL-6 after adjustment for confounders. Higher levels of CRF may play an important role for lowering some inflammatory biomarkers in central adiposity.

The association of cardiorespiratory fitness with endothelial or smooth muscle vasodilator function.

Maximal oxygen consumption (VO2max) is strongly associated with peripheral vasodilator function as determined by exercise-induced vasodilation. However, findings with regard to its relation with non-exercise-stimulated vasodilation are unclear. The purpose of this study was to systematically review published literature reporting associations between VO2max and endothelial function (EF) or smooth muscle function (SMF). We conducted a systematic search of MEDLINE, Cochrane and Web of Science, since their inceptions until April 2014 for articles reporting the association between (a) VO2max during incremental exercise and (b) endothelium-dependent or -independent vasodilator function, by means of correlation and/or regression analysis. Fifty-six articles exploring 88 associations between VO2max and vascular EF or SMF were included, involving a total of 4159 healthy and diseased subjects. VO2max was determined by incremental cycle ergometer (64%), treadmill (33%) and cycle ergometer/treadmill (3%) exercise. Vasodilator function variables were assessed in the upper limb (86%), lower limb (10%) and both upper and lower limbs (3%). Most of the evaluated bivariate associations involved EF stimuli such as flow-mediated dilation (FMD) (n = 29) or blood flow occlusion (BFO) (n = 18). VO2max was significantly associated with FMD and BFO in 59% and 67% of bivariate associations and 46% and 33% of age-independent associations, respectively. Explored bivariate associations regarding SMF involved sodium nitroprusside (SNP) iontophoresis (n = 7) and nitrate-mediated dilation (NMD) (n = 4). VO2max was associated with NMD in 50% of bivariate associations and 50% of age-independent associations. VO2max was not associated with SNP iontophoresis. Results were similar for associations including only healthy subjects. The association between VO2max and EF or SMF is moderately frequent and independent of health status, despite very few studies having assessed vasodilator function in the lower limb.

Association of cardiorespiratory fitness and overweight with risk of type 2 diabetes in Japanese men.

ObjectiveExisting evidence is limited on what extent fitness can counterbalance type 2 diabetes mellitus (T2DM) risk associated with obesity. We investigated the joint association of weight status and estimated VO2max, a marker of fitness, with the risk of developing T2DM among Japanese men using haemoglobin A1c and fasting glucose criterion.MethodsThe present study included 3,523 male employees aged 18–61 years without diabetes who provided health check-up and fitness data in Japan in 2003–2005. We calculated hazard ratios and 95% confidence intervals for incident diabetes using the Cox regression model.ResultsDuring a mean follow-up of 6.0 years, 199 men developed diabetes. Multivariable-adjusted hazard ratios (95% confidence interval) of diabetes were 1.00 (reference), 1.44 (1.01–2.07), and 1.48 (1.03–2.13) for the highest through the lowest tertile of fitness (P for trend = 0.04). Additional adjustment for body mass index largely attenuated the association of fitness with diabetes. Joint analysis showed that adjusted hazard ratios of diabetes were 1.00, 1.32, 2.94, and 1.83 in normal weight high-fit men, normal weight low-fit men, overweight high-fit men, and overweight low-fit men, respectively.ConclusionThe results suggest that weight control is more important than fitness in prevention of type 2 diabetes in Japanese men.