KIJANI App to Promote Physical Activity in Children and Adolescents: Protocol for a Mixed Method Evaluation.

BACKGROUND: The prevalence of physical inactivity among children and adolescents is alarmingly high despite the well-documented and comprehensive benefits of regular physical activity (PA). Therefore, PA promotion should start early in childhood and adolescence. Although reducing recreational screen time in children and adolescents is an urgent concern, digital approaches have the potential to make activity promotion attractive and age appropriate for the target group. KIJANI is a mobile app approach to promote PA in children and adolescents via gamification and augmented reality. OBJECTIVE: This study protocol aims to describe the KIJANI intervention in detail, as well as the evaluation approach. METHODS: KIJANI is based on the concept that virtual coins can be earned through PA, for example, in the form of a collected step count. With these coins, in turn, blocks can be bought, which can be used to create virtual buildings and integrate them into the player's real-world environment via augmented reality. PA of users is detected via accelerometers integrated into the smartphones. KIJANI can be played at predefined play locations that were comprehensively identified as safe, child-friendly, and attractive for PA by the target group in a partner project. The evaluation process will be divided into 2 different stages. The phase-I evaluation will be a mixed methods approach with one-on-one semistructured interviews and questionnaires to evaluate the user experience and receive feedback from the target group. After the implementation of results and feedback from the target group, the phase-II evaluation will proceed in the form of a 2-arm randomized controlled trial, in which the effectiveness of KIJANI will be assessed via objectively measured PA as well as questionnaires. RESULTS: The study received ethical approval from the ethical board of the Technical University of Munich. Participants for the phase-I evaluation are currently being recruited. CONCLUSIONS: The study will help to determine the efficacy, applicability, and user experience of a gamified activity promotion application in children and adolescents. Overall, digital health approaches provide easy and wide reachability at low cost and are age appropriate and attractive for the target group of adolescents. Strategies have to be developed to apply digital health approaches in the best possible way for activity promotion. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/55156.

Effect of Training on Vascular Function and Repair in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Exercise training improves peak oxygen uptake (V.O2peak) in heart failure with preserved ejection fraction (HFpEF). Multiple adaptations have been addressed, but the role of circulating endothelium-repairing cells and vascular function have not been well defined. OBJECTIVES: The authors investigated effects of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) on vascular function and repair in HFpEF. METHODS: This study is a subanalysis of the OptimEx-Clin (Optimizing Exercise Training in Prevention and Treatment of Diastolic Heart Failure) study randomizing patients with HFpEF (n = 180) to HIIT, MICT, or guideline control. At baseline, 3, and 12 months, the authors measured peripheral arterial tonometry (valid baseline measurement in n = 109), flow-mediated dilation (n = 59), augmentation index (n = 94), and flow cytometry (n = 136) for endothelial progenitor cells and angiogenic T cells. Abnormal values were defined as outside 90% of published sex-specific reference values. RESULTS: At baseline, abnormal values (%) were observed for augmentation index in 66%, peripheral arterial tonometry in 17%, flow-mediated dilation in 25%, endothelial progenitor cells in 42%, and angiogenic T cells in 18%. These parameters did not change significantly after 3 or 12 months of HIIT or MICT. Results remained unchanged when confining analysis to patients with high adherence to training. CONCLUSIONS: In patients with HFpEF, high augmentation index was common, but endothelial function and levels of endothelium-repairing cells were normal in most patients. Aerobic exercise training did not change vascular function or cellular endothelial repair. Improved vascular function did not significantly contribute to the V.O2peak improvement after different training intensities in HFpEF, contrary to previous studies in heart failure with reduced ejection fraction and coronary artery disease. (Optimizing Exercise Training in Prevention and Treatment of Diastolic Heart Failure [OptimEx-Clin]; NCT02078947).

Oscillometric pulse wave velocity estimated via the Mobil-O-Graph shows excellent accuracy in children, adolescents and young adults: an invasive validation study.

AIMS: Increased arterial stiffness, measured as arterial pulse wave velocity (PWV) is associated with an elevated cardiovascular risk. Although noninvasive PWV measurement methods have been validated by invasive measurement, there is little such data on pediatric patients. The purpose of this study was to 'fill the gap' by validating PWV obtained by Mobil-O-Graph in children, adolescents in comparison to young adults. METHODS: Sixty patients (25 male, mean age 16.6 years; range 3-35 years) were included in this study. Fifty-one patients underwent cardiac catheterization after a heart transplantation (HTX) and nine for interventional atrial septal defect-closure. Specific invasive pulse wave velocities were assessed for the ascending aorta (aPWV) and entire central aorta (cPWV). These invasive PWV results were compared to simultaneously measured brachial cuff readings using Mobil-O-Graph (oPWV) stratified by age in two groups (PEDIATRICS <18 years|ADULTS ≥18 years). RESULTS: Correlation analysis showed a positive linear relation between both invasive PWV measurements and the oPWV in all ages (cPWV/oPWV: r  = 0.417, aPWV/oPWV: r  = 0.628; P  < 0.001). The oPWV data agreed better with the aPWV in mean-value comparisons and correlations with mean difference in PEDIATRICS was 0.41 ±â€Š0.41 m/s (95% confidence interval 0.27-0.55). We also found the cPWV to be faster than the aPWV particularly in adults. In addition, cPWV correlated closer with age ( r  = 0.393, P  < 0.05). CONCLUSION: Estimated oPWV using the Mobil-O-Graph demonstrated excellent accuracy in adults and pediatric patients. Therefore, the Mobil-O-Graph can be implemented as an ambulatory PWV measuring tool for pediatric cardiovascular risk stratification. CLINICAL TRIAL REGISTRATION: German clinical trial registration, DRKS00015066.

Development and validation of a 1-km cardio-trekking test to estimate cardiorespiratory fitness in healthy adults.

Maximum oxygen uptake (V̇O2max), the gold standard measure of cardiorespiratory fitness (CRF), supports cardiovascular risk assessment and is mainly assessed during maximal spiroergometry. However, for field use, submaximal exercise tests might be appropriate and feasible. There have been no studies attempting a submaximal test protocol involving uphill hiking. This study aimed to develop and validate a 1-km cardio-trekking test (CTT) controlled by heart rate monitoring and Borg's 6-20 rating of perceived exertion (RPE) scale to predict V̇O2max outdoors. Healthy participants performed a maximal incremental treadmill walking laboratory test and a submaximal 1-km CTT on mountain trails in Austria and Germany, and V̇O2max was assessed with a portable spirometry device. Borg's RPE scale was used to control the exercise intensity of the CTT. All subjects wore a chest strap to measure heart rate (HR). A total of 134 participants (median age: 56.0 years [IQR: 51.8-63.0], 43.3 % males) completed both testing protocols. The prediction model is based on age, gender, smoking status, weight, mean HR, altitude difference, duration, and the interaction between age and duration (R2 = 0.65, adj. R2 = 0.63). Leave-one-out cross-validation revealed small shrinkage in predictive accuracy (R2 = 0.59) compared to the original model. Submaximal exercise testing using uphill hiking allows for practical estimation of V̇O2max in healthy adults. This method may allow people to engage in physical activity while monitoring their CRF to avert unnecessary cardiovascular events.

Assessment of Exercise Intensity for Uphill Walking in Healthy Adults Performed Indoors and Outdoors.

BACKGROUND: Borg's rating of perceived exertion (BRPE) scale is a simple, but subjective tool to grade physical strain during exercise. As a result, it is widely used for the prescription of exercise intensity, especially for cardiovascular disease prevention. The purpose of this study was to assess and compare relationships between BRPE and physiological measures of exercise intensity during uphill walking indoors and outdoors. METHODS: 134 healthy participants [median age: 56 years (IQR 52-63)] completed a maximal graded walking test indoors on a treadmill using the modified Bruce protocol, and a submaximal 1 km outdoor uphill cardio-trekking test (1 km CTT). Heart rate (HR) and oxygen consumption (V̇O2) were continuously measured throughout both tests. BRPE was simultaneously assessed at the end of each increment on the treadmill, while the maximal BRPE value was noted at the end of the 1 km CTT. RESULTS: On the treadmill, BRPE correlated very high with relative HR (%HRmax) (ρ = 0.88, p < 0.001) and V̇O2 (%V̇O2max) (ρ = 0.89, p < 0.001). During the 1 km CTT, a small correlation between BRPE and %HRmax (ρ = 0.24, p < 0.05), respectively %V̇O2max was found (ρ = 0.24, p < 0.05). CONCLUSIONS: Criterion validity of BRPE during uphill walking depends on the environment and is higher during a treadmill test compared to a natural environment. Adding sensor-based, objective exercise-intensity parameters such as HR holds promise to improve intensity prescription and health safety during uphill walking in a natural environment.

Valorization of Natural Cardio Trekking Trails Through Open Innovation for the Promotion of Sustainable Cross-generational Health-Oriented Tourism in the Connect2Move Project: Protocol for a Cross-sectional Study.

BACKGROUND: Hiking is one of the most popular forms of exercise in the alpine region. However, besides its health benefits, hiking is the alpine activity with the highest incidence of cardiac events. Most incidents occur due to overexertion or underestimation of the physiological strain of hiking. OBJECTIVE: This project will establish a standardized cardio trekking test trail to evaluate the exercise capacity of tourists within hiking areas and deliver a tool for the prevention of hiking-associated cardiac incidents. Further, individual exercise intensity for a hiking tour will be predicted and visualized in digital maps. METHODS: This cooperation study between Austria and Germany will first validate a 1-km outdoor cardio trekking test trail at 2 different study sites. Then, exercise intensity measures on 8-km hiking trails will be evaluated during hiking to estimate overall hiking intensity. A total of 144 healthy adults (aged >45 years) will perform a treadmill test in the laboratory and a 1-km hiking test outdoors. They will wear a portable spirometry device that measures gas exchange, as well as heart rate, walking speed, ventilation, GPS location, and altitude throughout the tests. Estimation models for exercise capacity based on measured parameters will be calculated. RESULTS: The project "Connect2Move" was funded in December 2019 by the European Regional Development Fund (INTERREG V-A Programme Austria-Bavaria - 2014-2020; Project Number AB296). "Connect2Move" started in January 2020 and runs until the end of June 2022. By the end of April 2022, 162 participants were tested in the laboratory, and of these, 144 were tested outdoors. The data analysis will be completed by the end of June 2022, and results are expected to be published by the end of 2022. CONCLUSIONS: Individual prediction of exercise capacity in healthy individuals with interest in hiking aims at the prevention of hiking-associated cardiovascular events caused by overexertion. Integration of a mathematical equation into existing hiking apps will allow individual hiking route recommendations derived from individual performance on a standardized cardio trekking test trail. TRIAL REGISTRATION: ClinicalTrails.gov NCT05226806; https://clinicaltrials.gov/ct2/show/NCT05226806. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/39038.

Sedentary Behavior in Childhood, Lower Arterial Compliance and Decreased Endothelial Function-Cross Sectional Data From a German School Cohort.

BACKGROUND: Endothelial function by flow-mediated dilatation assesses early markers of atherosclerotic progression. Greater amounts of physical activity and physical fitness in children are associated with cardiovascular health benefits. We aimed to explore factors, influencing endothelial function and arterial compliance in a cohort of healthy school children. METHODS: The 94 participants (41 girls, 53 boys) in the study were young, healthy children from a German school cohort. Anthropometric data, body composition and blood pressure were assessed. Blood was drawn (8 h overnight fast), assessing total cholesterol, high density lipoprotein and low density lipoprotein and triglycerides. Endothelial function was diagnosed by flow-mediated dilatation with ultrasonography (ALOKA/Hitachi, Prosound alpha 6). Tracking gates were set on the intima in B-mode. The waveform of diameter changes over the cardiac cycle was displayed in real time using the FMD-mode of the eTRACKING system. Changes in arterial diameter at baseline, ischaemia and vasodilatation were measured. A symptom limited pulmonary exercise test on a bicycle ergometer was performed to test cardiorespiratory fitness. Physical activity was assessed using GT3x accelerometers (Actigraph, USA), over 4 days (including 1 week-end day), with a minimum wear-time duration of 10 h. RESULTS: The median age was 12.2 years (11.8-12.8). Children were normal weight, blood lipid profiles (cholesterol, high-density lipoprotein, low-density lipoprotein, triglyceride) were in normal range. Baseline measurements during the diagnostics of endothelial function revealed higher arterial compliance of the brachial artery in boys. Boys' cardiorespiratory fitness was higher than compared to girls. Boys met the recommendations of 60 min moderate to vigorous activity, whereas girls were significantly less active and did not meet current recommendations. More time spent in sedentary activity was the main predictor for lower arterial compliance (adjusted for age and sex), accounting for 14% of the variance. No significant model revealed, analyzing the influencing factors such as anthropometric data, blood lipids, physical activity and fitness on endothelial function. CONCLUSION: This is the first study on endothelial function in association to objectively measured physical activity and cardiorespiratory fitness in healthy school children in Germany. The study highlights the importance of reducing time spent being sedentary to maintain endothelial health.

Association Between Physical Activity Intensity Levels and Arterial Stiffness in Healthy Children.

BACKGROUND: Physical activity (PA) has a substantial impact on arterial stiffness in adults; however, evidence regarding children is scarce. The aim of this study was to examine the association between objectively measured PA with different intensities and surrogate measures of arterial stiffness in healthy children. METHODS: Altogether, 80 children (41 girls and 39 boys, ranging from 8-11 y) participated in this prospective, cross-sectional study. Sedentary time and PA of light, moderate, and vigorous intensity levels were measured over a period of 7 days by accelerometry. Arterial stiffness parameters, including pulse wave velocity and central systolic blood pressure (cSBP), were noninvasively assessed by the oscillometric Mobil-O-Graph. Associations were tested using multiple linear regressions with adjustments for potential confounders (α ≤ .05). RESULTS: PA of moderate intensity was negatively associated with cSBP (ß = -0.266, P = .017). PA of vigorous intensity was inversely related to pulse wave velocity (ß = -0.225, P = .045) and cSBP (ß = -0.286, P = .010), respectively. CONCLUSION: Higher time spent in PA of moderate and vigorous intensity is associated with reduced pulse wave velocity and lower cSBP values in children. It suggests that PA is a favorable determinant of arterial health.

Primary Prevention: No Associations of Strength and Cardiorespiratory Fitness Status With Arterial Stiffness in Young School Children.

Pulse wave velocity (PWV) and central systolic blood pressure (CSBP) are well-established biomarkers of arterial stiffness. Further, fitness is known to be an important protective factor in adults in respect of vascular stiffening. However, the association of both muscular and cardiorespiratory fitness (CRF) with arterial properties in younger individuals has been inconsistent. The aim of the present study was to investigate the relationship between anthropometric data, CRF, strength status, and arterial stiffness parameters in German primary school children. A total of 76 children, age 6-11 years (63.2% males) were examined. Peripheral systolic blood pressure (PSBP) [mmHg] and peripheral diastolic blood pressure (PDBP) [mmHg] and PWV [m/s] were measured non-invasively after 10 min of rest with the oscillometric cuff-based Mobil-O-Graph (IEM, Healthcare, Stolberg, Germany). CSBP [mmHg] was calculated using the ARCSolver Algorithm (Austrian Institute of Technology, Vienna, Austria) based on the recorded brachial pulse waves. CRF was measured using the validated Progressive Aerobic Cardiovascular Endurance run (PACER), also called shuttle-run test, for estimating maximal aerobic capacity (VO2max). Hand-grip strength as an indicator of overall muscle strength was determined with the Jamar Analog Hand Dynamometer. The results were recorded in kilograms [kg]. For more detailed analyses, the study group was divided into subcohorts, namely a risk group including children with abnormal blood pressure or high body weight, and a healthy subgroup. Healthy children showed a positive association between PWV and body mass index (BMI) (p = 0.016) and CSBP and BMI (p = 0.033), respectively. Hand-grip strength was positively associated with CSBP (left: p = 0.013, right: p = 0.015) and PWV (left: p = 0.008, right: p = 0.002), as well as the number of shuttle run rounds were positively correlated to PWV (p = 0.038) in the whole cohort. No significant association of converted VO2max with arterial PWV was found. The multivariate regression analysis explained 38.8% (R 2 = 0.388) of the variance and the model was a significant predictor of PWV [F (6, 29) = 3.060, p = 0.019], however, none of the integrated covariates (BMI, number of shuttle run rounds, VO2max, dominant hand-grip strength) contributed significantly to the model. The lack of associations between fitness, strength and arterial stiffness might be explained by the few harmful lifestyle factors influencing vascular changes in the first decade of life.

Vascular health determinants in children.

BACKGROUND: The epidemic of cardiovascular disease (CVD) in the twentieth century generated numerous population-based surveys. These results clearly demonstrate that many factors are causally related to the development of atherosclerosis. Eighty percent of the CVD can be explained by smoking, high blood pressure, deterioration of lipid and glucose metabolism and physical inactivity. CVD is a disease that becomes clinically apparent in adults. However, it is undisputed that this disease develops over a long period of time due to progressive, subclinical changes in the cardiovascular system. The early manifestation of arteriosclerosis correlates with traditional risk factors. METHODS: This brief report focusses on determinates of vascular health. It describes non-invasive diagnostic methods such as oscillometric analysis of pulse wave velocity (PWV), ultrasound measurement of carotid structure and function as well as brachial endothelial function. Special attention is paid to possible correlations with physical activity, fitness and exercise. RESULTS: Non-invasive diagnostic methods to determine vascular health are applicable in children. The influence of physical activity and the relationship between aerobic fitness and arterial compliance (AC) remain controversial. First results in young athletes demonstrated an increased carotid intima-media thickness (cIMT), by revealing arterial elasticity. The mechanism and determinants explaining these adaptations have not been fully explained in young healthy athletes. CONCLUSIONS: Traditional cardiovascular risk factors act early in life and have a major impact on the development of atherosclerosis. The results underline that the prevention strategies and risk factor control should begin in childhood. The emphasis in the present report lied on the determination of vascular health, analyzing arterial structure and function, using non-invasive diagnostic methods. Vascular health and its relation to obesity, hypertension, physical activity and exercise were emphasized. The harmonization of knowledge and methods would greatly increase the comparability of existing results. To further elucidate the clinical relevance, the mechanisms linking arterial structure and compliance function with physical activity, fitness and exercise need further clinical investigation to enhance early preventive intervention strategies.

Postexercise changes in peripheral and central blood pressure during a 24-hour ambulatory blood pressure monitoring in healthy young men.

BACKGROUND: Central systolic blood pressure (cSBP), a measure of arterial stiffness, determines the afterload of the heart and provides greater prognostic significance regarding cardiovascular outcomes than peripheral systolic blood pressure (pSBP). Physical exercise is associated with an acute hypotensive effect on pSBP, but the significance of exercise on cSBP is missing. This study investigates the effect of a single exercise bout on pSBP and cSBP during a 24-hour ambulatory blood pressure monitoring (ABPM). METHODS: In 25 healthy male individuals (27.5±5.5 years) baseline pSBP and cSBP values were determined in a supine position using the oscillometric Mobil-O-Graph device. Afterward, they performed a maximum cardiopulmonary exercise test (CPET) on a bicycle ergometer. The 24-hour ABPM was launched 15 minutes after terminating CPET. RESULTS: Significant dipping of cSBP was found compared to baseline values in the first (-6.8 [-9.9 to -3.7] mmHg; P<0.001) second (-7.4 [-10.6 to -4.2] mmHg; P<0.001) and third hour (-6.4 [-11.5 to -1.3]; P=0.016) after exercise. Afterwards, cSBP continuously increases but remains significant reduced to baseline in the third (-6.4 [-11.5 to -1.3] mmHg; P=0.016), and fifth hour (-4.3 [-8.2 to -0.4] mmHg; P=0.033). There were only significant changes in pSBP compared to baseline values after 10 hours till the night period. The dipping pattern in the night period was similar in pSBP and cSBP. CONCLUSIONS: 24-h postexercise responses of pSBP and cSBP differs significantly. This suggests a different regulatory mechanism of exercise on the peripheral and central arteries that have further be elucidated.

Effects of Mobile Health Including Wearable Activity Trackers to Increase Physical Activity Outcomes Among Healthy Children and Adolescents: Systematic Review.

BACKGROUND: Children and adolescents do not meet the current recommendations on physical activity (PA), and as such, the health-related benefits of regular PA are not achieved. Nowadays, technology-based programs represent an appealing and promising option for children and adolescents to promote PA. OBJECTIVE: The aim of this review was to systematically evaluate the effects of mobile health (mHealth) and wearable activity trackers on PA-related outcomes in this target group. METHODS: Electronic databases such as the Cochrane Central Register of Controlled Trials, PubMed, Scopus, SPORTDiscus, and Web of Science were searched to retrieve English language articles published in peer-reviewed journals from January 2012 to June 2018. Those included were articles that contained descriptions of interventions designed to increase PA among children (aged 6 to 12 years) only, or adolescents (aged 13 to 18 years) only, or articles that include both populations, and also, articles that measured at least 1 PA-related cognitive, psychosocial, or behavioral outcome. The interventions had to be based on mHealth tools (mobile phones, smartphones, tablets, or mobile apps) or wearable activity trackers. Randomized controlled trials (RCTs) and non-RCTs, cohort studies, before-and-after studies, and cross-sectional studies were considered, but only controlled studies with a PA comparison between groups were assessed for methodological quality. RESULTS: In total, 857 articles were identified. Finally, 7 studies (5 with tools of mHealth and 2 with wearable activity trackers) met the inclusion criteria. All studies with tools of mHealth used an RCT design, and 3 were of high methodological quality. Intervention delivery ranged from 4 weeks to 12 months, whereby mainly smartphone apps were used as a tool. Intervention delivery in studies with wearable activity trackers covered a period from 22 sessions during school recess and 8 weeks. Trackers were used as an intervention and evaluation tool. No evidence was found for the effect of mHealth tools, respectively wearable activity trackers, on PA-related outcomes. CONCLUSIONS: Given the small number of studies, poor compliance with accelerometers as a measuring instrument for PA, risk of bias, missing RCTs in relation to wearable activity trackers, and the heterogeneity of intervention programs, caution is warranted regarding the comparability of the studies and their effects. There is a clear need for future studies to develop PA interventions grounded on intervention mapping with a high methodological study design for specific target groups to achieve meaningful evidence.

Reduced arterial stiffness in very fit boys and girls.

Low cardiorespiratory fitness is associated with higher cardiovascular risk, whereas high levels of cardiorespiratory fitness protect the cardiovascular system. Carotid intima-media thickness and arterial distensibility are well-established parameters to identify subclinical cardiovascular disease. Therefore, this study investigated the influence of cardiorespiratory fitness and muscular strength on carotid intima-media thickness and arterial distensibility in 697 children and adolescents (376 girls), aged 7-17 years. Cardiorespiratory fitness and strength were measured with the test battery FITNESSGRAM; carotid intima-media thickness, arterial compliance, elastic modulus, stiffness index ß, and pulse wave velocity ß were assessed by B- and M-mode ultrasound at the common carotid artery. In bivariate correlation, cardiorespiratory fitness was significantly associated with all cardiovascular parameters and was an independent predictor in multivariate regression analysis. No significant associations were obtained for muscular strength. In a one-way variance analysis, very fit boys and girls (58 boys and 74 girls>80th percentile for cardiorespiratory fitness) had significantly decreased stiffness parameters (expressed in standard deviation scores) compared with low fit subjects (71 boys and 77 girls<20th percentile for cardiorespiratory fitness): elastic modulus -0.16±1.02 versus 0.19±1.17, p=0.009; stiffness index ß -0.15±1.08 versus 0.16±1.1, p=0.03; and pulse wave velocity ß -0.19±1.02 versus 0.19±1.14, p=0.005. Cardiorespiratory fitness was associated with healthier arteries in children and adolescents. Comparison of very fit with unfit subjects revealed better distensibility parameters in very fit boys and girls.

Body Segment Kinematics and Energy Expenditure in Active Videogames.

OBJECTIVE: Energy expenditure (EE) in active videogames (AVGs) is a component for assessing its benefit for cardiovascular health. Existing evidence suggests that AVGs are able to increase EE above rest and when compared with playing passive videogames. However, the association between body movement and EE remains unclear. Furthermore, for goal-directed game design, it is important to know the contribution of body segments to EE. This knowledge will help to acquire a certain level of exercise intensity during active gaming. Therefore, the purpose of this study was to determine the best predictors of EE from body segment energies, acceleration, and heart rate during different game situations. MATERIALS AND METHODS: EE and body segment movement of 17 subjects, aged 22.1 ± 2.5 years, were measured in two different AVGs. In randomized order, the subjects played a handheld-controlled Nintendo(®) Wii™ tennis (NWT) game and a whole body-controlled Sony EyeToy(®) waterfall (ETW) game. Body segment movement was analyzed using a three-dimensional motion capture system. From the video data, mean values of mechanical energy change and acceleration of 10 body segments were analyzed. RESULTS: Measured EE was significantly higher in ETW (7.8 ± 1.4 metabolic equivalents [METs]) than in NWT (3.4 ± 1.0 METs). The best prediction parameter for the more intense ETW game was the energy change of the right thigh and for the less intense hand-controlled NWT game was the energy change of the upper torso. Segment acceleration was less accurate in predicting EE. CONCLUSION: The best predictors of metabolic EE were the thighs and the upper torso in whole body and handheld-controlled games, respectively. Increasing movement of these body segments would lead to higher physical activity intensity during gaming, reducing sedentary behavior.

Increased intima-media thickness is not associated with stiffer arteries in children.

OBJECTIVE: Subclinical atherosclerosis can be assessed via sonographic measurement of intima-media thickness and carotid artery distensibility, both may already be pathologically altered in childhood. Therefore, the purpose of this study was to provide reference percentiles and investigate possible associations between alterations of intima-media thickness and distensibility. METHODS: Carotid intima-media thickness and distensibility was measured via B- and M-mode ultrasound. Distensibility was defined by arterial compliance, elastic modulus, stiffness parameter ß, and local pulse wave velocity ß. Age- and height-dependent reference values were calculated separately for boys and girls among 690 (intima-media thickness) and 870 (distensibility) non-obese children aged 7-17 years. RESULTS: Intima-media thickness and distensibility did not increase significantly with age or differ between boys and girls. Systolic blood pressure and body mass index were independent predictors of intima-media thickness, while an increased systolic blood pressure or pulse pressure was associated with stiffer arteries. Increased intima-media thickness was accompanied by higher arterial compliance and lower stiffness. CONCLUSION: Using this healthy cohort, we describe a functional and non-pathological arterial adaptation wherein an increase in intima-media thickness is not associated with stiffer arteries.

Intima-media thickness and arterial function in obese and non-obese children.

BACKGROUND: Obesity is an independent cardiovascular risk factor that contributes to the development of atherosclerosis. Subclinical forms of the disease can be assessed via sonographic measurement of carotid intima-media thickness (cIMT) and distensibility - both may already be altered in childhood. As childhood obesity increases to an alarming extent, this study compares vascular data of obese with normal weight boys and girls to investigate the influence of obesity on cIMT and distensibility of the carotid arteries. METHODS: cIMT and distensibility of 46 obese children (27 girls) aged 7-17 years were compared with measures of 46 sex- and age-matched normal weight controls. cIMT and distensibility were measured by B- and M-mode ultrasound and expressed as standard deviation scores (SDS). Arterial distensibility was defined by arterial compliance (AC), elastic modulus (Ep), stiffness index ß (ß), and local pulse wave velocity ß (PWV ß). RESULTS: Obese girls had significantly stiffer arteries compared with normal weight girls (Ep SDS 0.64 ± 1.24 vs. 0 ± 1.06, ß SDS 0.6 ± 1.17 vs. -0.01 ± 1.06 p < .01, PWV ß 0.54 ± 1.2 vs. -0.12 ± 1.05 p < .05). No significant differences were observed for boys. In multiregression analysis, BMI significantly influenced Ep, ß and PWV ß but not cIMT and AC. CONCLUSIONS: Obese girls seemed to be at higher cardiovascular risk than boys, expressed by stiffer arteries in obese girls compared with normal weight girls. Overall, BMI negatively influenced parameters of arterial stiffness (Ep, ß and PWV ß) but not compliance or cIMT.

Reduction of exercise capacity in children from summer to winter is associated with lower sporting activity: a serial study.

BACKGROUND: Declining activity in children over the past decades is thought to be one of the main risk factors for an early development of exercise intolerance and obesity. Taking this background into account, this prospective study investigated the seasonal change of children's physical activity and its association with objective measures of exercise capacity. METHODS: A total of 96 children from two schools in Munich (42 girls, age 12.4 ± 0.8 y) underwent a cardiopulmonary exercise test (CPET) and an assessment of their daily activities (school sport, club sport, leisure sport) twice. Baseline testing was conducted in summer 2011. Follow-up examination was performed during winter 2012. RESULTS: From summer to winter, self-reported sporting activity decreased from 10.6 ± 4.1 to 8.5 ± 4.3 h/wk (P < 0.001) as school sport (P < 0.001) and leisure sport activities (P = 0.002) decreased, but the activity associated with club sport did not (P = 0.700). In parallel, peak oxygen uptake (VO2) declined from 102.0 ± 17.5 to 96.9 ± 17.9 % of predicted (P < 0.001). This decline in VO2 was associated with a reduction in overall sporting activity (r = 0.234; P < 0.032). CONCLUSION: Enhancing sporting activity in children during winter might be important to maintaining their exercise capacity.

Currently, children with congenital heart disease are not limited in their submaximal exercise performance.

OBJECTIVES: In several former studies, adolescents and adults with congenital heart disease (CHD) had a reduced exercise capacity even with defects considered to be simple. Currently, children might get better medical management and less restrictions concerning an active lifestyle or sports activities. The exercise performance of this new generation of children with CHD has to be evaluated. METHODS: In the year 2010, 88 children (12.7 years, 52 males), 11-14 years old, with various CHD performed a cardiopulmonary exercise test in our institution. These children were matched for age and gender with healthy subjects who underwent the same procedure at a school survey. RESULTS: In comparison with healthy controls, children with CHD had a diminished peak oxygen uptake (CHD: 35.5 ml/min/kg vs controls: 42.4 ml/min/kg; P < 0.001) corresponding to 87.1% (CHD) and 99.5% (Controls) of the reference value, respectively. Peak oxygen uptake decreased with the severity of the heart defect (r = -0.410; P < 0.001). However, there was no difference in oxygen uptake at the ventilatory threshold (CHD: 20.6 ml/min/kg vs controls: 21.5 ml/min/kg; P = 0.68). CONCLUSIONS: Currently, children with CHD are not limited in their submaximal exercise performance. However, there is still a reduction in peak oxygen uptake.

Sex differences of carotid intima-media thickness in healthy children and adolescents.

OBJECTIVES: In pediatric cardiovascular health prevention non-invasive diagnostics of subclinical atherosclerosis is essential for screenings and interventional purposes. Increased carotid artery intima-media thickness (IMT) has been reported in the presence of cardiovascular risk factors in childhood. However, little information exists regarding the age and sex distribution of IMT as stated in adults. This study investigates first, if IMT sonography is reliable and feasible; second, calculates sex- and age-specific percentiles; third, re-confirms IMT associations to cardiovascular risk parameters and analyses predictors for age-adjusted IMT. METHODS: 267 healthy pupils (age 6-17 years) were examined prospectively. Standardized IMT sonography and offline analysis were performed. Anthropometric data, BMI, body composition, blood pressure were taken; Spearman's rank correlation coefficient and multiple stepwise linear regression analyses were calculated. RESULTS: Intra-observer variability: CV was 2.42% (n=132; MD=0.012mm; r=0.849); inter-observer variability: CV was 1.71% (n=75; MD=0.013mm; r=0.780). Age- and sex-specific IMT percentiles for age groups 8/9 to 14/15 years were calculated. IMT values were higher in boys than in girls at the same age. Systolic blood pressure and IMT were positively related in boys (p<0.001, r=0.31) and girls (p=0.005, r=0.24). Predictors for age-adjusted IMT: systolic blood pressure was shown to be a predictor (r(2)=0.10, beta=0.31, p<0.001) in boys; weight emerged as a predictor (r(2)=0.19, beta=0.43, p<0.001) in girls. CONCLUSION: The main study benefit is the provision of IMT percentiles for both sexes for the age groups 8/9 to 14/15 years. The results suggest that sex-specific prevention should be given further attention in a comprehensive and multi-risk parameters approach.

[Interventions for caregivers of stroke patients: need and effectiveness]. / Interventionskonzepte für Angehörige von Schlaganfallpatienten: Bedarf und Effektivität.

After discharge from hospital most stroke patients are being cared for by relatives. In the majority of cases it does mean long-term demands for relatives and often it has also an effect on their health. There is a variety of possibilities for offering support to relatives in accomplishing their tasks and thus contribute to a relief of burden. There has not yet been enough research investigating how various intervention concepts really meet the needs of the relatives and how effective the interventions reduce the burden of the caregivers. Five types of intervention concepts for supporting relatives of stroke patients can be differentiated so far: special services, training, counselling, social support through other caregivers and multi-component interventions. On the basis of 42 intervention studies an attempt is being made to give a preliminary statement about the effectiveness of intervention models. The multi-component interventions combined with psychotherapeutic strategies seem to emerge as a recommendable concept.