Heart rate agreement between the 20-meter shuttle run test and virtual system in healthy children: a cross-sectional study.

BACKGROUND: Earlier studies evaluated the physiological responses to video games in children with different clinical conditions; however, no study has compared active video games with an incremental field test in healthy children. The purpose of this study was to verify the agreement between the 20-m shuttle run test (20 m-SRT) and virtual system (VS). METHODS: This is a cross-sectional study of 235 children (9.0 ± 0.8 years, 109 boys). The two tests were performed one week apart and the children were instructed not to engage in any physical exercise or sports in the 24 h preceding each test. Their resting heart rate was monitored for one minute and then throughout the tests. To evaluate the influence of motivation on the 20 m SRT and (VS), at the end of the tests the children were asked to rate their motivation on a scale of zero to 10, zero being "not cool" and 10 "awesome". Perceived exertion at the end of the tests was assessed using the modified Borg scale. RESULTS: Maximum heart rate (HRmax) did not differ between the 20 m-SRT and VS (194.4 ± 10.2 bpm vs. 193.2 ± 13.8 bpm, respectively). Both tests were similar for intensity > and < 96% HRmax. The children showed greater exertion on the Borg scale and motivation during the VS. The multiple logistic regression model showed that motivation (p = 0.98), sex (p = 0.53), age (p = 0.61), nutritional status (p = 0.65), and speed (p = 0.18) were not predictive factors of the child's reaching HRmax. CONCLUSION: VS can be used as a tool to evaluate the intensity of maximal exercise tests, given that the percentage of children who achieved HRmax did not differ between the VS and 20 m SRT. The perceived exertion scales were correlated, but only the modified Borg scale correlated with HRmax in the 20 m SRT. The tests are motivational, and most children obtained the maximum VS score.

Functional capacity and quality of life in children and adolescents with sickle cell anemia.

OBJECTIVE: To evaluate the functional and exercise capacity, lung function, quality of life of children and adolescents with sickle cell anemia (SCA HbSS) and to test the reproducibility of functional capacity tests in this population. METHOD: Cross-sectional study with volunteers with SCA Hb-SS (SCAG), aged 6-18 years matched in age and gender to the control group (CG) with healthy individuals. Spirometry, 5-repetition sit-to-stand test (5STS-test), modified shuttle test (MST), and Pediatric Quality of Life Questionnaire (PedsQL) were performed. The reproducibility of 5STS-test and MST was evaluated: RESULTS: Forty eight volunteers of SCAG and 48 of CG were evaluated. Lung function of SCAG (FVC: 92 ± 15% pred.; FEV1 /FVC: 84 ± 8% pred.) was worse than the CG (104 ± 15% pred.; FEV1 /FVC: 90 ± 6% pred.) p < 0.05. SCAG had worse functional capacity registered by distance walked: 576 m (515-672 m) and 5STS-test: 8 s (7.4-8.9 s) compared with the CG who showed distance walked: 1010 m (887-1219 m) and 5STS-test: 7 s (7.0-8.1 s), p < 0.001. SCAG had worse quality of life compared to CG, p < 0.05. The reproducibility of MST (ICC 0.99 (0.98-0.99 IC-95%)) and 5STS-test (ICC 0.80 (0.69-0.88) was considered good, p < 0.001. CONCLUSION: Children and adolescents with sickle cell anemia presented worse capacity to walk or run, and to perform sit-to-stand test when compared with their control peers. Additionally, they have poorer quality of life. The MST and 5STS-test showed good reproducibility to be applied in pediatric individuals with SCA.

The PAY test: a new approach for assessing functional performance in children and adolescents with asthma.

OBJECTIVE: To develop, validate, and test the reproducibility of a new test capable of assessing functional performance in children and adolescents (PAY test: Performance Activity in Youth). METHODS: participants without and with asthma were included in the development and validation phases, respectively. The PAY test includes five activities: transition from sitting to standing, walking 10 m, step climbing, shoulder extension and flexion, and star jumps. Participants underwent the Pediatric Glittre test (TGlittre-P test time), modified shuttle test (MST), and cardiopulmonary exercise test (CPET). OUTCOMES: PAY test and TGlittre-P test times, oxygen uptake (VO2peak), and distance walked in the MST. RESULTS: 8 healthy volunteers, aged 12 (7 - 15) years old were included in the development phase and 34 participants with asthma, aged 11 (7 -14) years old, in the validation phase. The PAY test elicited greater physiological responses (VO2peak 33.5 ± 6.9 mL/kg) than the TGlittre-P (VO2peak: 27.4 ± 9.0 mL/kg), but lower than the MST (VO2peak: 48.9 ± 14.2 mL/kg) and CPET (VO2peak: 42.0 ± 8.8 mL/kg), p < .05. Moderate correlation between the PAY test time and the TGlittre-P time (r = 0.70, p < .001) and distance walked in the MST (r = -0.72, p < .001). The PAY test time was longer in participants with asthma than in healthy participants (3.1 [3.0 - 3.3] min vs. 2.3 [2.1 - 2.4 min]), p < .001.; and the test was reproducible (ICC 0.78, CI 95% 0.55-0.90, p < .001). CONCLUSIONS: The PAY test is a valid and reproducible tool for assessing functional performance in children and adolescents with asthma.

Exercise-induced desaturation in subjects with non-cystic fibrosis bronchiectasis: laboratory-based tests versus field-based exercise tests.

OBJECTIVE: To investigate the validity of field walking tests to identify exercise-induced hypoxemia and to compare cardiorespiratory responses and perceived effort between laboratory-based and field-based exercise tests in subjects with bronchiectasis. METHODS: This was a cross-sectional study involving 72 non-oxygen-dependent participants (28 men; mean age = 48.3 ± 14.5 years; and mean FEV1 = 54.1 ± 23.4% of the predicted value). The participants underwent cardiopulmonary exercise testing (CPET) on a treadmill and constant work-rate exercise testing (CWRET) on the same day (1 h apart). In another visit, they underwent incremental shuttle walk testing (ISWT) and endurance shuttle walk testing (ESWT; 1 h apart). Desaturation was defined as a reduction in SpO2 ≥ 4% from rest to peak exercise. RESULTS: CPET results were compared with ISWT results, as were CWRET results with ESWT results. There was no difference in the magnitude of desaturation between CPET and ISWT (-7.7 ± 6.3% vs. -6.6 ± 5.6%; p = 0.10) and between CWRET and ESWT (-6.8 ± 5.8% vs. -7.2 ± 6.3%; p = 0.50). The incremental tests showed an agreement in the magnitude of desaturation in the desaturation and no desaturation groups (42 and 14 participants, respectively; p < 0.01), as did the endurance tests (39 and 16 participants; p < 0.01). The magnitude of desaturation was similar among the participants who did or did not reach at least 85% of the maximum predicted HR. CONCLUSIONS: Field exercise tests showed good precision to detect desaturation. Field tests might be an alternative to laboratory tests when the clinical question is to investigate exercise-induced desaturation in subjects with bronchiectasis.

Validity and reliability of 2-min step test in patients with symptomatic peripheral artery disease.

BACKGROUND: Although 2-min step test (2MST) has been useful in general population, no study has investigated its validity in patients with peripheral artery disease (PAD). OBJECTIVE: To analyze the validity and reliability of the 2MST in patients with PAD and claudication symptoms. METHODS: Twenty-four patients with PAD and claudication symptoms were recruited and performed the 2MST comparing it to the six-minute walk test (6MWT). Test performance, step indicators, and heart rate were measured during the test. Validity was verified using Pearson correlation between the performance of 2MST (number of steps) and 6MWT (distance and number of steps). The reliability was analyzed by the intraclass correlation coefficient and by the limits of agreement of Bland and Altman. RESULTS: A similar performance was observed between the two 2MST (65 ±â€¯10 steps vs. 66 ±â€¯10 steps, p = 0.43) with a significant intraclass coefficient correlation of 0.945. The bias between tests was of 0.79 steps with the limits of agreement between -9.6 and 11.2 steps. The 90% minimum detectable difference was 3.2 steps. The number of steps in 2MST was significantly correlated with the number of steps in 6MWT (r = 0.55, p<0.01). However, the number of steps in 2MST did not correlate with distance in the 6MWT (r = 0.26, p = 0.23). The peak heart rate was lower in 2MST compared to 6MWT (p<0.05). CONCLUSION: The 2MST present adequate reliability and validity in patients with symptomatic PAD.

Systemic Inflammation and Oxidative Stress in Adults with Bronchiectasis: Association with Clinical and Functional Features.

OBJECTIVES: To compare the inflammatory and oxidative stress (OS) states of adults with bronchiectasis with those of healthy controls and correlate inflammatory and OS levels with lung function and physical capacity. METHODS: This study used a cross-sectional design. Seventy-four adults with bronchiectasis (age: 49±15 years, forced expiratory volume in 1 second [FEV1]: 52.5±25.6%) and 42 healthy controls (age: 44±17 years, FEV1: 95.9±14.0%) performed cardiopulmonary exercise tests and incremental shuttle walking tests. Their physical activity in daily life, inflammatory cytokine, and antioxidant levels in plasma were measured. RESULTS: Compared to that of the controls, the levels of interleukin (IL)-6 (p<0.001), IL-10 (p<0.001), carbonylated proteins (p=0.001), and superoxide anions (p=0.046) were significantly increased in adults with bronchiectasis. Catalase activity was also reduced in this group (p<0.001). The inflammatory markers IL-1ß, IL-6, and tumor necrosis factor-α correlated negatively with aerobic capacity (r=-0.408, r=-0.308, and r=-0.207, respectively). We observed similar correlations with OS markers (thiobarbituric acid and carbonyls; r=-0.290 and r=0.379, respectively), and these markers also significantly correlated with the aerobic capacity. CONCLUSIONS: Adults with bronchiectasis presented an increased systemic inflammatory response that correlated negatively with physical capacity.

Effect of transcranial direct current stimulation and multicomponent training on functional capacity in older adults: protocol for a randomized, controlled, double-blind clinical trial.

INTRODUCTION: When physical activity contains training of at least three components such as balance, coordination and strength, among others, it is called multicomponent training. This type of training is recommended for improving the functional capacity in elderly individuals but has no lasting effects. The association of transcranial direct current stimulation (tDCS) with other types of therapy has been shown to facilitate the enhancement and prolongation of therapy outcomes. AIM: The objective of this study is to evaluate the effect of multicomponent training associated with active or sham tDCS on the performance of functional capacity in the elderly before treatment, after treatment and 30 days after the end of treatment. The secondary objective will be to correlate the performance of the primary outcome (functional capacity assessed by the Glittre Daily Life Activity Test) with walking capacity (by 6-min walk test), balance (with the mini-Balance Evaluation Systems Test), functional independence (by the Functional Independence Measure) and quality of life (with the World Health Organization Quality of Life Instrument). METHODS: Twenty-eight elderly people from the community will participate in the study, and will be randomized into two groups: 1) multicomponent training associated with active tDCS; and 2) multicomponent training associated with sham tDCS. The multicomponent training sessions will be held twice a week for 12 weeks, totaling 24 sessions. The tDCS will be administered over the dominant dorsolateral prefrontal cortex at the same time as multicomponent training, with an intensity of 2 mA, for 20 min. The evaluations will be made pretraining, after 24 training sessions and 30 days after the end of the training. DISCUSSION: We hypothesize that tDCS, when associated with multicomponent training, can potentiate and prolong the effects of this training on the functional capacity of the elderly. If this hypothesis is confirmed, this protocol may contribute to a longer-lasting physical rehabilitation of the elderly, encouraging them to maintain their independent daily activities for longer. TRIAL REGISTRATION: The study was registered in the Brazilian Clinical Trial Registry (RBR-2crd42) and received approval from the Human Research Ethics Committee of University Nove de Julho, São Paulo, Brazil (process number 3.077.953).

Physiological Responses During Field Walking Tests in Adults with Bronchiectasis.

BACKGROUND: Field walking tests are commonly used in patients with chronic pulmonary diseases for assessment of functional capacity. However, the physiological demands and magnitude of desaturation on 6-min walk test (6MWT), incremental shuttle walk test (ISWT), and endurance shuttle walk test (ESWT) have not been investigated in patients with bronchiectasis. The objective of this study was to compare the physiological responses and the magnitude of desaturation of subjects with bronchiectasis when performing the 6MWT, ISWT, and ESWT. METHODS: Thirty-two subjects underwent the 6MWT, ISWT, and ESWT on 3 different days. Pulmonary gas exchange, heart rate, and [Formula: see text] were measured in all tests. RESULTS: There were no differences in the peak rate of oxygen uptake, ventilation, dyspnea, and leg fatigue between the tests. Equivalent cardiac demand (ie, heart rate at peak) was observed with the 6MWT (137 ± 21 beats/min) and the ESWT (142 ± 21 beats/min), but this was lower in the ISWT (135 ± 19 beats/min) compared to ESWT (P < .05). Most subjects achieved a vigorous exercise intensity (heart rate of 70-90% of predicted) in all tests. There was no difference in desaturation among the tests (6MWT: -6.8 ± 6.6%, ISWT: -6.1 ± 6.0%, and ESWT: -7.0 ± 5.4%). CONCLUSIONS: The 6MWT, ISWT, and ESWT induced similar physiological responses at the peak of exercise, eliciting a vigorous exercise intensity. The magnitude of desaturation was similar across tests. This means these tests can be used interchangeably for evaluation of exercise-induced desaturation.

The PAY test: a new approach for assessing functional performance in children and adolescents with asthma

Abstract Objective: To develop, validate, and test the reproducibility of a new test capable of assessing functional performance in children and adolescents (PAY test: Performance Activity in Youth). Methods: participants without and with asthma were included in the development and validation phases, respectively. The PAY test includes five activities: transition from sitting to standing, walking 10 m, step climbing, shoulder extension and flexion, and star jumps. Participants underwent the Pediatric Glittre test (TGlittre-P test time), modified shuttle test (MST), and cardiopulmonary exercise test (CPET). Outcomes: PAY test and TGlittre-P test times, oxygen uptake (VO2peak), and distance walked in the MST. Results: 8 healthy volunteers, aged 12 (7 -15) years old were included in the development phase and 34 participants with asthma, aged 11 (7-14) years old, in the validation phase. The PAY test elicited greater physiological responses (VO2peak 33.5 ± 6.9 mL/kg) than the TGlittre-P (VO2peak: 27.4 ± 9.0 mL/kg), but lower than the MST (VO2peak: 48.9 ± 14.2 mL/kg) and CPET (VO2peak: 42.0 ± 8.8 mL/kg), p < .05. Moderate correlation between the PAY test time and the TGlittre-P time (r = 0.70, p < .001) and distance walked in the MST (r = -0.72, p < .001). The PAY test time was longer in participants with asthma than in healthy participants (3.1 [3.0 - 3.3] min vs. 2.3 [2.1 - 2.4 min]), p < .001.; and the test was reproducible (ICC 0.78, CI 95% 0.55-0.90, p < .001). Conclusions: The PAY test is a valid and reproducible tool for assessing functional performance in children and adolescents with asthma.

Determinants of Peripheral Muscle Strength and Activity in Daily Life in People With Bronchiectasis.

Background: Bronchiectasis is characterized by a progressive structural lung damage, recurrent infections and chronic inflammation which compromise the exertion tolerance, and may have an impact on skeletal muscle function and physical function. Objective: The purpose of this study was to compare peripheral muscle strength, exercise capacity, and physical activity in daily life between participants with bronchiectasis and controls and to investigate the determinants of the peripheral muscle strength and physical activity in daily life in bronchiectasis. Design: This study used a cross-sectional design. Methods: The participants' quadriceps femoris and biceps brachii muscle strength was measured. They performed the incremental shuttle walk test (ISWT) and cardiopulmonary exercise testing, and the number of steps/day was measured by a pedometer. Results: Participants had reduced quadriceps femoris muscle strength (mean difference to control group = 7 kg, 95% CI = 3.8-10.1 kg), biceps brachii muscle strength (2.1 kg, 95% CI = 0.7-3.4 kg), ISWT (227 m, 95% CI = 174-281 m), peak VO2 (6.4 ml/Kg/min, 95% CI = 4.0-8.7 ml/Kg/min), and number of steps/day (3,332 steps/day, 95% CI = 1,758-4,890 steps/day). A lower quadriceps femoris strength is independently associated to an older age, female sex, lower body mass index (BMI), higher score on the modified Medical Research Council scale, and shorter distance on the ISWT (R2 = 0.449). Biceps brachii strength is independently associated with sex, BMI, and dyspnea (R2 = 0.447). The determinants of number of daily steps were dyspnea and distance walked in ISWT, explaining only 27.7% of its variance. Limitations: Number of steps per day was evaluated by a pedometer. Conclusions: People with bronchiectasis have reduced peripheral muscle strength, and reduced aerobic and functional capacities, and they also are less active in daily life. Modifiable variables such as BMI, dyspnea, and distance walked on the ISWT are associated with peripheral muscle strength and physical activity in daily life.

Validation and reliability of the Glittre-ADL test to evaluate functional capacity in older adults

INTRODUCTION: The decline in functional capacity (FC) interferes with the functional independence of older adults, so it is important to assess the FC and use appropriate instruments for this. OBJECTIVE: To investigate the Glittre Activities of Daily Living (ADL) test's validity and reliability for assessing functional capacity in older adults. METHODS: Cross-sectional study with a sample of 100 elderly (68 ± 5.16 years). To assess the convergent validity, the Six-Minute Walk Test (6MWT) and the Timed Up and Go Test (TUG) were performed. The intra-examiner test-retest of the Glittre-ADL test was performed on the same day with a 30-minute interval between repetitions and inter-examiner reliability with an interval of seven days. RESULTS: There was a strong correlation between the Glittre-ADL test and the 6MWT (r=-0,75; p<0.001) and the TUG (r=0.77; p<0.001). The intra-examiner and inter-examiner reliability was excellent (ICC)=0.91 and 95% CI=0.14-0.97; p<0.001 and ICC=0.91; 95% CI: 0.86-0.94; p<0.001, respectively). CONCLUSION: The Glittre-ADL test demonstrated that it is valid and that its reliability is adequate to assess functional capacity in older adults.

Does home-based pulmonary rehabilitation improve functional capacity, peripheral muscle strength and quality of life in patients with bronchiectasis compared to standard care?

BACKGROUND: Home-based pulmonary rehabilitation is a promising intervention that may help patients to overcome the barriers to undergoing pulmonary rehabilitation. However, home-based pulmonary rehabilitation has not yet been investigated in patients with bronchiectasis. OBJECTIVES: To investigate the effects of home-based pulmonary rehabilitation in patients with bronchiectasis. METHODS: An open-label, randomized controlled trial with 48 adult patients with bronchiectasis will be conducted. INTERVENTIONS: The program will consist of three sessions weekly over a period of 8 weeks. Aerobic exercise will consist of stepping on a platform for 20min (intensity: 60-80% of the maximum stepping rate in incremental step test). Resistance training will be carried out using an elastic band for the following muscles: quadriceps, hamstrings, deltoids, and biceps brachii (load: 70% of maximum voluntary isometric contraction). CONTROL: The patients will receive an educational manual and a recommendation to walk three times a week for 30min. All patients will receive a weekly phone call to answer questions and to guide the practice of physical activity. The home-based pulmonary rehabilitation group also will receive a home visit every 15 days. MAIN OUTCOME MEASURES: incremental shuttle walk test, quality of life, peripheral muscle strength, endurance shuttle walk test, incremental step test, dyspnea, and physical activity in daily life. The assessments will be undertaken at baseline, after the intervention, and 8 months after randomization. DISCUSSION: The findings of this study will determine the clinical benefits of home-based pulmonary rehabilitation and will contribute to future guidelines for patients with bronchiectasis. TRIAL REGISTRATION: www.ClinicalTrials.gov (NCT02731482). https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S00060X6&selectaction=Edit&uid=U00028HR&ts=2&cx=1jbszg.

Normative values and reference equation for the six-minute step test to evaluate functional exercise capacity: a multicenter study / Valores normativos e equação de referência para o teste do degrau de seis minutos para avaliar a capacidade funcional de exercício: um estudo multicêntrico

ABSTRACT Objective: To establish normative values and a reference equation for the number of steps climbed during the six-minute step test (6MST) in healthy adults, and to assess the reliability of the test and of the equation. Methods: This was a multicenter cross-sectional study involving 468 healthy volunteers (age range: 18-79 years) recruited from the general community in six research laboratories across different regions of Brazil, which is a country with continental dimensions. The 6MST was performed twice (30-min interval), and clinical, demographic, and functional variables were evaluated. An independent sample of 24 volunteers was evaluated to test the reference equation a posteriori. Results: The number of steps had excellent test-retest reliability (intraclass correlation coefficient = 0.96 [95%CI: 0.95-0.97]), and the mean number of steps was 175 ± 45, the number being 14% greater in males than in females. The best performance on the test was correlated with age (r = −0.60), sex (r = 0.28), weight (r = 0.13), height (r = 0.41), BMI (r = −0.22), waist circumference (r = −0.22), thigh circumference (r = 0.15), FVC (r = 0.54), and physical activity level (r = 0.17; p < 0.05 for all). In the regression analysis, age, sex, height, and weight explained 42% of the variability of the 6MST. Normative values were established for the 6MST according to age and sex. There was no difference between the 6MST values from the independent sample and its predicted values (157 ± 29 steps vs. 161 ± 25 steps; p = 0.47; 97% of predicted values). Conclusions: The normative values and the reference equation for the 6MST in this study seem adequate to accurately predict the physical functional performance in adults in Brazil.

RESUMO Objetivo: Estabelecer valores normativos e uma equação de referência para o número de degraus subidos no teste do degrau de seis minutos (TD6) em adultos saudáveis, bem como avaliar a confiabilidade do teste e da equação. Métodos: Estudo transversal multicêntrico com 468 voluntários saudáveis (faixa etária: 18-79 anos) recrutados na comunidade geral em seis laboratórios de pesquisa em diferentes regiões do Brasil, um país de dimensões continentais. O TD6 foi realizado duas vezes (com 30 min de intervalo entre uma e outra), e foram avaliadas variáveis clínicas, demográficas e funcionais. Uma amostra independente composta por 24 voluntários foi avaliada para testar a equação de referência a posteriori. Resultados: O número de degraus subidos apresentou excelente confiabilidade teste-reteste [coeficiente de correlação intraclasse = 0,96 (IC95%: 0,95-0,97)], e a média de degraus subidos foi de 175 ± 45, sendo 14% maior no sexo masculino. O melhor desempenho no teste correlacionou-se com as seguintes variáveis: idade (r = −0,60), sexo (r = 0,28), peso (r = 0,13), estatura (r = 0,41), IMC (r = −0,22), circunferência da cintura (r = −0,22), circunferência da coxa (r = 0,15), CVF (r = 0,54) e nível de atividade física (r = 0,17; p < 0,05 para todos). Na análise de regressão, idade, sexo, estatura e peso explicaram 42% da variabilidade do TD6. Foram estabelecidos valores normativos para o TD6 de acordo com a idade e o sexo. Não houve diferença entre os valores do TD6 na amostra independente e os valores previstos (157 ± 29 vs. 161 ± 25 degraus subidos; p = 0,47; 97% dos valores previstos). Conclusões: Os valores normativos e a equação de referência para o TD6 neste estudo parecem adequados para predizer com precisão o desempenho físico funcional em adultos no Brasil.

Exercise-induced desaturation in subjects with non-cystic fibrosis bronchiectasis: laboratory-based tests versus field-based exercise tests / Dessaturação induzida pelo exercício em pacientes com bronquiectasia não fibrocística: testes laboratoriais versus testes clínicos de campo

ABSTRACT Objective: To investigate the validity of field walking tests to identify exercise-induced hypoxemia and to compare cardiorespiratory responses and perceived effort between laboratory-based and field-based exercise tests in subjects with bronchiectasis. Methods: This was a cross-sectional study involving 72 non-oxygen-dependent participants (28 men; mean age = 48.3 ± 14.5 years; and mean FEV1 = 54.1 ± 23.4% of the predicted value). The participants underwent cardiopulmonary exercise testing (CPET) on a treadmill and constant work-rate exercise testing (CWRET) on the same day (1 h apart). In another visit, they underwent incremental shuttle walk testing (ISWT) and endurance shuttle walk testing (ESWT; 1 h apart). Desaturation was defined as a reduction in SpO2 ≥ 4% from rest to peak exercise. Results: CPET results were compared with ISWT results, as were CWRET results with ESWT results. There was no difference in the magnitude of desaturation between CPET and ISWT (−7.7 ± 6.3% vs. −6.6 ± 5.6%; p = 0.10) and between CWRET and ESWT (−6.8 ± 5.8% vs. −7.2 ± 6.3%; p = 0.50). The incremental tests showed an agreement in the magnitude of desaturation in the desaturation and no desaturation groups (42 and 14 participants, respectively; p < 0.01), as did the endurance tests (39 and 16 participants; p < 0.01). The magnitude of desaturation was similar among the participants who did or did not reach at least 85% of the maximum predicted HR. Conclusions: Field exercise tests showed good precision to detect desaturation. Field tests might be an alternative to laboratory tests when the clinical question is to investigate exercise-induced desaturation in subjects with bronchiectasis.

RESUMO Objetivo: Investigar a validade dos testes de caminhada de campo para identificar dessaturação durante o exercício, comparando os testes de exercício laboratoriais e clínicos de campo quanto às respostas cardiorrespiratórias e percepção de esforço em indivíduos com bronquiectasia não fibrocística. Métodos: Estudo transversal com 72 participantes não dependentes de oxigênio (28 homens; média de idade: 48,3 ± 14,5 anos; média do VEF1: 54,1 ± 23,4% do previsto). Os participantes foram submetidos ao teste de exercício cardiopulmonar (TECP) incremental em esteira e ao constant work-rate exercise testing (CWRET, teste de exercício com carga constante) em esteira, com intervalo de 1 h. Em outra visita, foram submetidos ao incremental shuttle walk test (ISWT, teste de caminhada incremental) e ao endurance shuttle walk test (ESWT, teste de caminhada de resistência), com intervalo de 1 h. A definição de dessaturação foi uma redução da SpO2 ≥ 4% do repouso ao pico do exercício. Resultados: O TECP e o ISWT resultaram em dessaturação de magnitude comparável (−7,7 ± 6,3% vs. −6,6 ± 5,6%; p = 0,10), assim como o fizeram o CWRET e o ESWT (−6,8 ± 5,8% vs. −7,2 ± 6,3%; p = 0,50). Houve concordância entre o TECP e o ISWT quanto ao número de participantes que apresentaram e não apresentaram dessaturação, respectivamente (42 e 14; p < 0,01), bem como entre o CWRET e o ESWT (39 e 16; p < 0,01). A magnitude da dessaturação foi semelhante nos participantes que atingiram ≥ 85% da FC máxima prevista ou não. Conclusões: Os testes de exercício de campo apresentaram boa precisão para detectar dessaturação. Os testes de campo podem ser uma alternativa aos testes de laboratório quando o objetivo é investigar a dessaturação durante o exercício em indivíduos com bronquiectasia.

Systemic inflammation and oxidative stress in adults with bronchiectasis: association with clinical and functional features

OBJECTIVES: To compare the inflammatory and oxidative stress (OS) states of adults with bronchiectasis with those of healthy controls and correlate inflammatory and OS levels with lung function and physical capacity. METHODS: This study used a cross-sectional design. Seventy-four adults with bronchiectasis (age: 49±15 years, forced expiratory volume in 1 second [FEV1]: 52.5±25.6%) and 42 healthy controls (age: 44±17 years, FEV1: 95.9±14.0%) performed cardiopulmonary exercise tests and incremental shuttle walking tests. Their physical activity in daily life, inflammatory cytokine, and antioxidant levels in plasma were measured. RESULTS: Compared to that of the controls, the levels of interleukin (IL)-6 (p<0.001), IL-10 (p<0.001), carbonylated proteins (p=0.001), and superoxide anions (p=0.046) were significantly increased in adults with bronchiectasis. Catalase activity was also reduced in this group (p<0.001). The inflammatory markers IL-1β, IL-6, and tumor necrosis factor-α correlated negatively with aerobic capacity (r=-0.408, r=-0.308, and r=-0.207, respectively). We observed similar correlations with OS markers (thiobarbituric acid and carbonyls; r=-0.290 and r=0.379, respectively), and these markers also significantly correlated with the aerobic capacity. CONCLUSIONS: Adults with bronchiectasis presented an increased systemic inflammatory response that correlated negatively with physical capacity.

Critical vs estimated heart rate in elderly subjects / Frequência cardíaca crítica x estimada em indíviduos idosos / Frecuencia cardíaca crítica x estimada en individuos de la tercera edad

ABSTRACT Introduction: Heart rate (HR) has been a simple and easy-to-use physiological parameter widely used to determine exercise intensity. The critical power fatigue limit model, known as the critical heart rate (CHR), can be extrapolated to HR. However, an estimate for a CHR mathematical model has not yet been extrapolated for upper limb exercise in the elderly. Objective: To compare the mathematical model previously used to estimate CHR with the heart rate values at the critical power (CP) during arm-ergometer exercises in elderly subjects. Methods: After an initial maximum-incremental exercise test on a cycle arm-ergometer, seven elderly people performed four high-intensity constant-load tests to the limit of tolerance (Tlim), to determine CP and critical heart rate (CHR). For each power output, the heart rate of the last five seconds (HRlim) and total time to exhaustion (in minutes) were obtained. The slope coefficients of the regression lines between HRlim and Tlim were defined as CHR, and between Wlim and Tlim as CP. A square-wave test was performed on a different day, in the power determined as equivalent to CP, and the heart rate at CP (CPHR) was assessed. Results: The HR-Tlim relationship was found to be hyperbolic in all subjects, who were able to sustain upper-limb exercise at CP for 20 min. CP attained 66.8±9.4% of peak work rate in the ramp test. The real average HR measured in the CP test was strikingly similar to the CHR calculated by the mathematical model of PC (137.6±16.9 versus 139.7±13.3bpm, respectively, p=0.53). There was strong correlation between the real and the estimated CHR. Conclusion: This study indicated that the maximal sustainable exercise intensity can be based on a physiological variable such as HR, and the CHR test can define exercise endurance, which can be useful in performance assessment and training prescription. Level of evidence II; Diagnostic studies - Investigating a diagnostic test.

RESUMO Introdução: A frequência cardíaca (FC) tem sido um parâmetro fisiológico fácil de usar, amplamente empregado para determinar a intensidade de exercício. O modelo de limiar de fadiga pela potência crítica pode ser extrapolado para a FC, conhecido como frequência cardíaca crítica (FCC). Entretanto, a estimativa para um modelo matemático da FCC ainda não foi extrapolada para o exercício de membros superiores em idosos. Objetivo: Comparar o modelo matemático para estimar a FCC usado anteriormente com os valores da frequência cardíaca na potência crítica (PC) durante exercícios com ergômetro de braço em idosos. Métodos: Depois de exercício inicial máximo incremental em um ciclo de ergômetro de braço, sete idosos realizaram quatro testes de carga constante até o limite de tolerância (Tlim) (para determinar a PC e a frequência cardíaca crítica (FCC). Para cada potência, foram obtidas a frequência cardíaca dos últimos cinco segundos (FClim) e o tempo total de exaustão (em minutos). Os coeficientes de declive das linhas de regressão entre FClim e Tlim foram definidos como FCC e entre CTlim e Tlim como PC. Um teste de onda quadrada foi realizado em um dia diferente, na potência que se determinou equivalente à PC, e a frequência cardíaca na PC (PCFC) foi avaliada. Resultados: Verificou-se que a relação FC-Tlim era hiperbólica em todos os indivíduos, que foram capazes de manter o exercício do membro superior na PC por 20 minutos. A PC atingiu 66,8 ± 9,4% da taxa de pico de trabalho no teste de rampa. A FC média real medida no teste de PC foi notavelmente semelhante à FCC calculada pelo modelo matemático de PC (137,6 ± 16,9 versus 139,7 ± 13,3 bpm, respectivamente, p = 0,53). Houve forte correlação entre FCC real e a estimado. Conclusão: Este estudo indicou que a intensidade máxima de exercício sustentável pode basear-se em uma variável fisiológica, como a FC, e que o teste de FCC pode definir a resistência ao exercício, o que pode ser útil para a avaliação do desempenho e para a prescrição do treinamento. Nível de evidência II; Estudos diagnósticos - Investigação de um exame para diagnóstico.

RESUMEN Introducción: La frecuencia cardíaca (FC) ha sido un parámetro fisiológico fácil de usar, ampliamente empleado para determinar la intensidad de ejercicio. El modelo de umbral de fatiga por la potencia crítica puede ser extrapolado para la FC, conocido como frecuencia cardíaca crítica (FCC). Entretanto, la estimativa para un modelo matemático de la FCC aún no fue extrapolada para el ejercicio de miembros superiores en personas de la tercera edad. Objetivo: Comparar el modelo matemático para estimar la FCC usado anteriormente con los valores de la frecuencia cardíaca en la potencia crítica (PC) durante ejercicios con ergómetro de brazo en personas de la tercera edad. Métodos: Después de ejercicio inicial máximo incremental en un ciclo de ergómetro de brazo, siete ancianos realizaron cuatro tests de carga constante hasta el límite de tolerancia (Tlim) para determinar la PC y la frecuencia cardíaca crítica (FCC). Para cada potencia, fueron obtenidas la frecuencia cardíaca de los últimos cinco segundos (FClim) y el tiempo total de agotamiento (en minutos). Los coeficientes de declive de las líneas de regresión entre FClim y Tlim fueron definidos como FCC y entre CTlim y Tlim como PC. Un test de onda cuadrada fue realizado en un día diferente, en la potencia que se determinó equivalente a la PC, y fue evaluada la frecuencia cardíaca en la PC (PCFC). Resultados: Se verificó que la relación FC-Tlim era hiperbólica en todos los individuos, que fueron capaces de mantener el ejercicio del miembro superior en la PC por 20 minutos. La PC alcanzó 66,8 ± 9,4% de la tasa de pico de trabajo en el test de rampa. La FC promedio real medida en el test de PC fue notablemente semejante a la FCC calculada por el modelo matemático de PC (137,6 ± 16,9 versus 139,7 ± 13,3 bpm, respectivamente, p = 0,53). Hubo fuerte correlación entre FCC real y la estimada. Conclusión: Este estudio indicó que la intensidad máxima de ejercicio sostenible puede basarse en una variable fisiológica, como la FC, y que el test de FCC puede definir la resistencia al ejercicio, lo que puede ser útil para la evaluación del desempeño y para la prescripción del entrenamiento. Nivel de evidencia II; Estudios diagnósticos - Investigación de un examen para diagnóstico.