An observational study in YPAP Model, sponsored by Hospital Universitario Pedro Ernesto. Active, not recruiting at 1 site in Brazil. Open to participants aged 10 Years to 13 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-03.
Sponsored by Hospital Universitario Pedro Ernesto · Observational
This cross-sectional observational study aims to test the original conceptual diagram of the Youth Physical Activity Promotion Model (YPAP) in Brazilian adolescents. The study evaluates the relationships among predisposing, enabling, and reinforcing correlates described in the YPAP framework and investigates how these correlates interact with one another according to the pathways proposed by the model. A convenience sample of adolescents aged 10 to 13 years will be recruited through broad public dissemination as part of a larger experimental intervention project. Data will be collected at a single time point. Instead of traditional linear analytical strategies, the study will adopt complex, flexible, and non-linear methods such as network analysis to examine how correlates interconnect and influence physical activity behavior. Secondary analyses will explore whether the structure and strength of associations differ across demographic subgroups such as sex and socioeconomic level.
The Youth Physical Activity Promotion Model (YPAP) conceptualizes physical activity behavior in youth as influenced by interacting correlates organized within predisposing, enabling, and reinforcing domains. These domains interact dynamically and collectively shape physical activity, forming a structured diagram originally proposed by Welk and colleagues. This study aims to test this conceptual diagram using data from Brazilian adolescents aged 10-13 years. The objective is to evaluate whether the empirical relationships among correlates follow the directional pathways and interactions proposed by the original YPAP model. This study will analyze baseline data collected as part of a broader experimental intervention, although no intervention or exposure occurs for the purpose of this cross-sectional analysis. Recruitment will occur through broad public dissemination linked to the host project and community outreach strategies. Given the complexity of the model and the expected multilevel interdependencies among correlates, the analysis strategy will rely on flexible, non-linear methods-most prominently network analysis-to explore how variables cluster, how correlates influence one another, and how these structures relate to normative patterns expected from the original YPAP framework. Secondary aims include testing whether observed associations vary by key demographic moderators described in the model (sex, socioeconomic level).
9,798 studies on the registry are indexed under Motor Activity; 1,910 are open to participants now.
This study's planned enrollment of 93 is close to the median of 98 across 1,235 observational studies indexed under Motor Activity.
Browse Motor Activity studies →Hospital Universitario Pedro Ernesto is the lead sponsor of 17 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Brazilian adolescents aged 10 to 13 years, recruited through broad public dissemination as part of a larger intervention project.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
All participants complete the same assessments in two days at a single time point. No arms or exposure groups, as this is an observational study.
Accelerometer-Measured Physical Activity (MVPA)
Minutes per day spent in sedentary, light, moderate, and vigorous intensity, measured using ActiGraph GT3X accelerometers and classified according to Evenson cut-points.
Time frame: Baseline (single assessment)
Total Body Mass
Total body mass will be measured using a digital electronic scale Filizola (model ID 1500; capacity: 150 kg; accuracy: 100 g). Measurements will be recorded in kilograms (kg).
Time frame: Baseline (single assessment)
Standing and Sitting Height
Standing height will be measured using a vertical stadiometer Sanny (model ES2020; millimetric scale; range up to 2.20 m), with the participant standing barefoot in the orthostatic position and the head aligned in the Frankfurt plane. Values will be recorded in centimeters (cm).
Time frame: Baseline (single assessment)
Body Mass Index (BMI)
Body Mass Index (BMI) will be calculated using measured total body mass and standing height, following World Health Organization (WHO) criteria (2007). Participants will be classified according to age- and sex-specific BMI nutritional status categories. Values will be expressed in kg/m².
Time frame: Baseline (single assessment)
Waist Circumference
Waist circumference will be measured using a metal measuring tape. Values will be recorded in centimeters (cm).
Time frame: Baseline (single assessment)
Waist-to-Height Ratio (WHtR)
The waist-to-height ratio will be calculated using measured waist circumference and standing height.
Time frame: Baseline (single assessment)
Body Fat Percentage
Body fat percentage will be assessed by Dual-Energy X-ray Absorptiometry (DXA) using a Lunar scanner from GE Healthcare. The device will be calibrated according to manufacturer guidelines. Participants will remain in the supine position, motionless, with upper and lower limbs aligned. Scans will be performed in high resolution and analyzed by the same trained technician.
Time frame: Baseline (single assessment)
Cardiorespiratory Fitness (Yo-Yo IR1C)
Cardiorespiratory fitness will be assessed using the Yo-Yo Intermittent Recovery Test Level 1 adapted for children (YoYo IR1C). The protocol consists of repeated 16-meter shuttle runs interspersed with a 4-meter active recovery zone and 10-second rest periods. Running pace is controlled by audio cues from a dedicated application, with progressive speed increments until voluntary exhaustion. Maximum heart rate (HRmax) will be recorded using a heart rate sensor Polar Electro (model H10). Test termination will occur when the participant fails to reach the designated line twice consecutively or demonstrates significant fatigue. Results will be used to estimate maximal oxygen uptake (VO2max) and HRmax.
Time frame: Baseline (single assessment)
Motor Competence (KTK)
Motor competence will be assessed using the Körperkoordinationstest für Kinder (KTK), developed by Klaus Kiphard and Friedhelm Schilling. The battery consists of four subtests evaluating distinct components of motor coordination: (1) dynamic balance through walking on beams of different widths; (2) speed and rhythm through two-foot lateral jumps performed for 15 seconds; (3) strength and motor control through single-leg jumps over progressively higher foam obstacles; and (4) lateral agility using two moving platforms over a fixed 20-second interval. Raw scores from each subtest will be converted into age- and sex-adjusted standardized scores and summed to generate a global motor index. All assessments will be conducted by trained evaluators to ensure procedural standardization and data reliability.
Time frame: Baseline (single assessment)
Cognitive Function (Tower of Hanoi)
Cognitive function will be assessed using the three-disk Tower of Hanoi task. The test consists of a base with three pegs and three disks of different sizes and colors, initially stacked on the left peg with the smallest disk on top. Participants must transfer the entire tower to the right peg while following two rules: only one disk may be moved at a time, and a larger disk may not be placed on top of a smaller one. The entire procedure will be video recorded to allow quantification of the total number of moves and the total time required to complete the task.
Time frame: Baseline (single assessment)
Perceived Health Status
Perceived health status will be assessed through a single question using a 5-point Likert scale. Adolescents will classify their health as: (1) poor, (2) fair, (3) good, (4) very good, or (5) excellent. Higher scores indicate better perceived health.
Time frame: Baseline (single assessment)
Motivation for Physical Activity (BREQ-2)
Motivation for physical activity will be assessed using the Behavioral Regulation in Exercise Questionnaire (BREQ-2), adapted for Portuguese. The questionnaire consists of items distributed across subscales evaluating amotivation, external regulation, introjected regulation, identified regulation, integrated regulation, and intrinsic motivation. Participants will respond on a 5-point Likert scale ranging from "Not true for me" to "Very true for me." Scores will be calculated for each regulatory style to characterize participants' motivational profile toward physical activity.
Time frame: Baseline (single assessment)
Self-Perception and Motor Competence (EAPH-A)
Self-perception will be assessed using the Escala de Autopercepção de Harter para Adolescentes (EAPH-A), the Brazilian adaptation of the Self-Perception Profile for Adolescents (SPPA). The instrument comprises five specific domains of self-perception-school competence, social competence, athletic competence, physical appearance, and behavioral conduct-along with a global self-esteem score. The scale uses a structured alternative-response format with four response levels, in which participants first choose which of two hypothetical descriptions best resembles them and then indicate whether the statement is "very true for me" or "somewhat true for me." This response structure reduces social desirability bias and enhances self-reflection.
Time frame: Baseline (single assessment)
Social Support for Physical Activity
Social support for physical activity will be assessed using a 12-item scale that captures different forms of support provided by parents and friends. Considering a typical week, adolescents will report the frequency (never, rarely, often, always) with which parents and friends encourage them, practice together, watch, comment, discuss, invite them to be active, or provide/arrange transportation to physical activity locations. Higher scores reflect greater perceived social support for engaging in physical activity.
Time frame: Baseline (single assessment)
Perceived Environment for Physical Activity
Perception of the environment for physical activity will be assessed using a scale composed of three domains. An overall score will be created by summing the items within each domain. Scores will then be divided into tertiles, with higher tertiles indicating more favorable perceptions of the environment for engaging in physical activity.
Time frame: Baseline (single assessment)
Attitude Toward Physical Activity
Attitude toward physical activity will be assessed using a five-item semantic differential scale. Two items evaluate affective/emotional aspects and three evaluate instrumental aspects. Participants will rate bipolar adjective pairs (safe-unsafe, fun-boring, important-unimportant, healthy-harmful, good-bad) on a 4-point scale. Higher scores indicate a more positive attitude toward physical activity
Time frame: Baseline (single assessment)
Self-Efficacy for Physical Activity
Self-efficacy for physical activity will be measured using a 12-item scale assessing confidence to engage in physical activity when facing commonly reported barriers. Items are rated on a 4-point Likert scale ranging from 1 ("strongly disagree") to 4 ("strongly agree"). Higher scores indicate greater self-efficacy to be physically active.
Time frame: Baseline (single assessment)
Stratified network structure by sex
Examination of whether networks of YPAP correlates differ between boys and girls.
Time frame: Baseline
Stratified network structure by socioeconomic level
Analysis of networks across socioeconomic categories to determine whether demographic moderators influence YPAP pathways. Socioeconomic status will be classified using the Critério Brasil, developed by the Associação Brasileira de Empresas de Pesquisa (ABEP). The instrument assesses household assets, access to services, and the educational level of the head of household, categorizing participants into economic strata ranging from A to E.
Time frame: Baseline
Maturational Status (Maturity Offset / PHV)
Maturational status will be estimated using the Peak Height Velocity (PHV) prediction equation (Maturity Offset), which uses anthropometric variables including standing height, body mass, sitting height, leg length, chronological age, and sex. The method provides an estimate, in years, of the time before or after the individual's PHV.
Time frame: Baseline (single assessment)
Plan to share: No — Individual participant data will not be shared due to ethical restrictions related to research involving minors.
Ran from Apr 2026 to primary completion in Jul 2026, 3 months.
Completion moved once since we started tracking on Sep 25, 2026: Sep 2026 → Dec 2026, on Oct 20, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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Hospital Universitario Pedro Ernesto