The 6-minute walking test (6MWT) is a simple assessment tool to evaluate exercise capacity. The result of the test is the distance that a subject can walk at a constant and normal pace within 6 minutes (6MWD) and reflects the aerobic/fitness performance related to walking function. Use of 6MWT has been relevant to assess exercise tolerance either in healthy children or in patients with, heart, lung and metabolic diseases. Our aim was to find 6MWT reference values in healthy Italian children. The 6MWT was performed in 5614 children aged 6–11 years recruited from primary Italian schools. Age related reference percentiles of the covered distance were gender-modeled. A linear and quadratic regression model was used to predict 6MWT performance. Males walked longer distances than females, respectively 598.8±83.9 m vs 592.1±77.6 m (p = 0.0016). According to the regression analysis, 6MWD was positively related to age, gender and height, while it was negatively related to body weight [(6MWD = -160.16 + 93.35× age (years) -4.05× age2 (years) +7.34× gender (m) +2.12× weight (kg) −2.50× height (cm)]. Reference values were established for the 6MWT in healthy children. The age related 6MWD percentiles provided a useful tool in the assessment of capacity in 6–11 year children, in fact they may be helpful to evaluate the effect of a given treatment or rehabilitation program and represent a feasible measure as to prevention within the primary school context. It was found a substantial difference from other countries for 6mwd values. In our study, factors such as age, weight and height were relevant for the prediction of 6MWD, similarly to other studies. Therefore, these variables should be taken into account in context of exercise performance.

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Six minute walk distance and reference values in healthy Italian children : a cross-sectional study

The study evaluates children in schools that participate in the School Health Program in the Northern region of Brazil with the objective of assessing whether their schools interfered in the development of overweight/obesity and how individual and school environment variables behave according to contextual analysis. The analyses were carried out with 1036 children from 25 municipal public schools in Northern Brazil that participated in the School Health Program. We evaluated both individual characteristics and scholar environment through univariate and multivariate logistic regressions to identify which of these factors were related to overweight/obesity as well as the effect of varying such associations. The considered individuals had an median age of 8 years, being 54.9% female and 27.8% presenting overweight/obesity. In multivariate logistic regression, the overweight/obesity variance in schools was 0.386 (individual variables) and 0.102 (individual and school variables), explaining 23.7% of the variation, reduction of ICC and MOR. The Akaike Information Criterion between the models was reduced and the likelihood ratio indicated better adequacy of the latter model. The investigated children had a greater chance of developing overweight/obesity when they performed 2+ sedentary activities/day, depending on school location as well as whether or not candies were sold in the school surroundings. On the other hand, a lower chance of developing overweight/obesity was identified in children that ate 5+ meals/day and practiced dance at school. We observed that the variables inherent to both individuals and schools favored the development of overweight/obesity in children. It is relevant that scholar curriculums incorporate healthy eating interventions and encourage body practices associated with policies that restrain the sale of ultra-processed food in schools as well as the development of intersectoral actions between education and health to control childhood obesity.

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Multilevel analysis of factors that influence overweight in children: research in schools enrolled in northern Brazil School Health Program.

Background 
Previous studies speculated that the Incremental Shuttle Walking Test (ISWT) is a maximal test in children and adolescents, however comparison between ISWT with cardiopulmonary exercise test has not yet performed. Furthermore, there is no regression equation available in the current literature to predict oxygen peak consumption (VO2 peak) in this population. This study aimed to assesses and correlate the cardiorespiratory responses of the ISWT with the cardiopulmonary exercise (CEPT) and to develop and validate a regression equation to predict VO2 peak in healthy sedentary adolescent boys.


Methods 
Forty-one participants were included in the study. In the first stage, the VO2 peak, respiratory exchange ratio (R peak), heart rate max (HR max) and percentage of predicted HR max (% predicted HR max) were evaluated in CEPT and ISWT (n = 26). Second, an equation was developed (n = 29) to predict VO2 peak. In both phases, the VO2 peak, respiratory exchange ratio R and hearth rate (HR) were evaluated. In the third stage, the validation equation was performed by another 12 participants.


Results 
Similar results in VO2 peak (P>0.05), R peak (P>0.05) and predicted maximum HR (P>0.05) were obtained between the ISWT and CEPT. Both tests showed moderate significant correlations of VO2 peak (r = 0.44, P = 0.002) e R peak (r = -0.53, P < 0.01), as well as the agreement of these measurements by Bland-Altman analysis (VO2 peak, bias = -0.13; R peak, bias = 0.0). Distance walked was the variable that explained 42.5% (R2 = 0.425, p = 0.0001) of the variance in VO2 peak. The equation was VO2 peak (predicted) = 20.94 + (0.02 x distance walked). The results obtained by the equation were not significantly different compared to the values obtained by the gas analyzer and the Bland-Altman analysis showed agreement (bias = 1.6).


Conclusion 
The ISWT produced maximal cardiorespiratory responses comparable to the CEPT, and the developed equation showed viability for the prediction of VO2 peak in healthy sedentary adolescent boys.

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Cardiorespiratory and metabolic responses and reference equation validation to predict peak oxygen uptake for the incremental shuttle waking test in adolescent boys.

Abstract Purpose We investigated respiratory muscle strength, diaphragm mobility, lung function, functional capacity, quality of life, body composition, breathing pattern, and chest wall (V T,CW) and compartmental volumes of Mucopolysaccharidosis (MPS) patients and compared these variables with matched healthy individuals. Methods A cross-sectional study with data analyzed separately according to age group. A total of 68 individuals (34 MPS and 34 matched-healthy subjects) were included. Six-minute walking test assessed functional capacity and ultrasound assessed diaphragm mobility during quiet spontaneous breathing (QB). Optoelectronic plethysmography assessed V T,CW and breathing pattern during QB in two different positions: seated and supine (45° trunk inclination). Results Body composition, lung function, respiratory muscle strength, and functional capacity were reduced in MPS (all p < 0.01). Diaphragm mobility was only reduced in adolescents (p = 0.01) and correlated with body composition and breathing pattern. Upper chest wall compartmental volumes were significantly lower in MPS, while abdominal volume only differed significantly in adolescents. Percentage contribution (%) of upper ribcage compartments to tidal volume was reduced in MPS children, whereas %AB was significantly increased compared with healthy subjects. Conclusion Lung function, respiratory muscle strength, functional capacity, diaphragm mobility, and quality of life are reduced in MPS compared with matched healthy subjects. V T,CW was mainly reduced due to pulmonary and abdominal ribcage impairment. Implications for Rehabilitation Reduction in respiratory muscle strength, functional capacity, diaphragm excursion and low lung volumes were found in individuals with Mucopolysaccharidoses (MPS). Chest wall volumes and the upper chest wall compartmental volumes during quiet spontaneous breathing are reduced in MPS. Assessment and monitoring of the respiratory system for individuals with MPS should be performed periodically through standardized assessments to enable identification of changes and early intervention by rehabilitation protocols. This study may provide the necessary basis for carrying out respiratoty rehabilitation protocols that can improving chest wall mechanics with breathing exercise in this group.

Chest wall volumes, diaphragmatic mobility, and functional capacity in patients with mucopolysaccharidoses

Objective: To validate the six-minute step test (6MST) and evaluate its reproducibility for determining exercise tolerance in healthy children aged 7-11 years. Methods: 66 healthy children, aged between 7 and 11 years old, were included in the research. The volunteers underwent the six-minute walk test (6MWT) and the 6MST. Results: A moderate positive correlation was observed between the distance covered on the 6MWT and the number of climbs on the 6MST (r = 0.43; p <0.001). The reproducibility of the variables in the 6MST was considered excellent in relation to the variables Performance (number of steps) (r = 0.92; CI = 0.87 to 0.87; p <0.001), systolic blood pressure (SBP) immediately after (r = 0, 87; CI = 0.79 to 0.92; p <0.001), SBP-1 'recovery (r = 0.84; CI = 0.74 to 0.90; p <0.001), maximum heart rate (HR) (r = 0 , 90; CI = 0.83 to 0.94; p <0.001), HR-immediately after (r = 0.88; CI = 0.81 to 0.93; p <0.001) and lower limb (LL) fatigue test (3rd min) (0.86; CI = 0.78 to 0.92; p <0.001). They also showed very good reproducibility at SBP-rest (r = 0.75; CI = 0.59 to 0.84; p <0.001), SBP-5 'recovery (r = 0.78; CI = 0.56 at 0.83; p <0.001), diastolic blood pressure (PAD) rest (r = 0.74; CI = 0.58 to 0.84; p <0.001), DBP -immediately after (r = 0.72; CI = 0.55 at 0.83; p <0.001), DBP-1'recovery (r = 0.77; CI = 0.63 to 0.86; p <0.001), DBP-5'recovery (r = 0.73; CI = 0.56 to 0.83; p <0.001), HR-rest (r = 0.73; CI = 0.60 to 0.86; p <0.001), LL fatigue-immediately after (r = 0, 72; CI = 0.54 to 0.83; p <0.001). Conclusion: The 6MST is safe, valid and with good intra-rater reproducibility in the assessment of exercise tolerance in healthy children aged 7-11 years.

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Validação do constructo e reprodutibilidade intra-avaliador do teste de degrau de 6 minutos em crianças saudáveis de 7-11 anos

INTRODUCTION: Brazil is a country with great climatic, socioeconomic, and cultural differences that does not yet have a reference value for the 6-min walk test (6MWT) in healthy children. To avoid misinterpretation, the use of equations to predict the maximum walk distance should be established in each country. OBJECTIVES: We sought to establish reference values and to develop an equation to predict the 6-min walk distance for healthy children in Brazil. METHODS: This is a cross-sectional multi-center study that included 1,496 healthy children, aged 7 to 12 y, assessed across 11 research sites in all regions of Brazil, and recruited from public and private schools in their respective regions. Each child was assessed for weight and height. Walk distance was our main outcome. An open-source software environment for statistical computing was used for statistical analysis. RESULTS: We observed a higher average distance walked by boys (531.1 m) than by girls (506.2 m), with a difference of 24.9 m ( P CONCLUSION: Reference values were established for the 6MWT in healthy children aged 7–12 y in Brazil.

http://rc.rcjournal.com/content/respcare/63/3/339.full-text.pdf

Reference Values for the 6-min Walk Distance in Healthy Children Age 7 to 12 Years in Brazil: Main Results of the TC6minBrasil Multi-Center Study.

Introduction: Cardiorespiratory fitness is markedly reduced in stroke subjects, resulting in patterns of inactivity andsedentary lifestyles. In this sense, tests of aerobic exercises are critical for the prescription of this type of training.Aims: To review the available data regarding the cardiorespiratory, metabolic parameters, and protocols used to assess cardiorespiratory fitness in stroke subjects, and to discuss their relevance for stroke rehabilitation. Method: A literature review was carried out in MEDLINE, CINAHL, EMBASE, and PEDro databases. The articles identified by the initial search strategy were evaluated, according to the following criteria: (1) the target population included stroke subjects, (2) employed a spirometric instrumentation, (3) reported results from randomized clinical trials, experimental,or quasi- experimental designs, and (4) included in the analyses any cardiorespiratory or metabolic parameters to assess cardiorespiratory fitness. Results: The 15 identified studies included a total sample of 665 stroke subjects. Theexperimental groups received training on cycle ergometers, treadmills, mobility, water, and unilateral lower limb exercises with isokinetic dynamometer. Most studies assessed oxygen consumption, two analyzed anaerobic threshold,and one examined heart rate and respiratory exchange ratios. Conclusions: Although differences between the studieswere found regarding the investigated outcomes, the assessment and training protocols, this review found evidencethat cardiorespiratory parameters, mainly oxygen consumption, were sensitive to training.

/pdf/ergospirometric-assessment-relevance-for-rehabilitation-of-3dsymgt877.pdf

Luiza Martins Faria

Papers

Reference Values for the 6-min Walk Distance in Healthy Children Age 7 to 12 Years in Brazil: Main Results of the TC6minBrasil Multi-Center Study.

Ergospirometric assessment: Relevance for rehabilitation of stroke subjects.