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J A Neder

Publications and source records attributed to J A Neder.

At least 19 recordsLinked to original sources
PubMed2006

A step test to assess exercise-related oxygen desaturation in interstitial lung disease.

A 6-min step test (6MST) may constitute a practical method for routinely assessing effort tolerance and exercise-related oxyhaemoglobin desaturation (ERD) in the primary care of patients with interstitial lung disease. In total, 31 patients (19 males) with idiopathic pulmonary fibrosis (n = 25) and chronic hypersensitivity pneumonia were submitted, on different days, to two 6MSTs. Physiological responses were compared with those found on maximal and submaximal cycle ergometer tests at the same oxygen uptake (V'(O(2))). Chronic breathlessness was also determined, as measured by the baseline dyspnoea index (BDI). Responses to 6MST were highly reproducible: 1.3+/-2.0 steps x min(-1), +/-5 beats x min(-1) (cardiac frequency), +/-50 mL x min(-1) (V'(O(2))), +/-7 L x min(-1) (minute ventilation) and +/-2% (arterial oxygen saturation measured by pulse oximetry (S(p,O(2)))). The number of steps climbed in 6 min was correlated to peak V'(O(2)) and the BDI. There were significant associations among the tests in relation to presence (change in S(p,O(2)) between rest and exercise > or = 4%) and severity (S(p,O(2)) <88%) of ERD. Four patients, however, presented ERD only in response to 6MST. Resting diffusing capacity of the lung for carbon monoxide and alveolar-arterial oxygen tension difference were the independent predictors of the number of steps climbed. A single-stage, self-paced 6-min step test provided reliable and reproducible estimates of exercise capacity and exercise-related oxyhaemoglobin desaturation in interstitial lung disease patients.

Adult↗
PubMed2006

Inspiratory fraction and exercise impairment in COPD patients GOLD stages II-III.

The inspiratory-to-total lung capacity ratio or "inspiratory fraction" (inspiratory capacity(IC)/total lung capacity (TLC)) may be functionally more representative than traditional indices of resting airflow limitation and lung hyperinflation in patients with chronic obstructive pulmonary disease (COPD). In the present retrospective study, a comparison was made of the individual performance of post-bronchodilator IC, IC/TLC and forced expiratory volume in one second (FEV(1)) in predicting a severely reduced peak oxygen uptake (V'(O(2)); <60% predicted) in 44 COPD patients Global Initiative for Chronic Obstructive Lung Disease stages II-III (post-bronchodilator FEV(1) ranging from 31-79% pred). Patients with lower IC/TLC values (<or=0.28) showed increased lung volumes and reduced exercise capacity as compared with other subjects. Following a multiple linear regression analysis, only IC/TLC and FEV(1) remained as independent predictors of V'(O(2)) (r(2) = 0.33). A receiver operating characteristic (ROC) curve analysis revealed that an IC/TLC <or=0.28 had the highest specificity (89.6%), positive predictive value (80%) and overall accuracy (86.3%) in identifying patients with V'(O(2)) <60% pred. In addition, the area under the ROC curve tended to be higher for IC/TLC than IC. In conclusion, post-bronchodilator total lung capacity-corrected inspiratory fraction provides useful information in addition to forced expiratory volume in one second and inspiratory capacity, to estimate the likelihood of chronic obstructive pulmonary disease patients to present with severely reduced maximal exercise capacity.

Aged↗
PubMed2005

Non-malignant consequences of decreasing asbestos exposure in the Brazil chrysotile mines and mills.

AIMS: To investigate the consequences of improvement in the workplace environment over six decades (1940-96) in asbestos miners and millers from a developing country (Brazil). METHODS: A total of 3634 Brazilian workers with at least one year of exposure completed a respiratory symptoms questionnaire, chest radiography, and a spirometric evaluation. The study population was separated into three groups whose working conditions improved over time: group I (1940-66, n = 180), group II (1967-76, n = 1317), and group III (1977-96, n = 2137). RESULTS: Respiratory symptoms were significantly related to spirometric abnormalities, smoking, and latency time. Breathlessness, in particular, was also associated with age, pleural abnormality and increased cumulative exposure to asbestos fibres. The odds ratios (OR) for parenchymal and/or non-malignant pleural disease were significantly lower in groups II and III compared to group I subjects (0.29 (0.12-0.69) and 0.19 (0.08-0.45), respectively), independent of age and smoking status. Similar results were found when groups were compared at equivalent latency times (groups I v II: 30-45 years; groups II v III: 20-25 years). Ageing, dyspnoea, past and current smoking, and radiographic abnormalities were associated with ventilatory impairment. Lower spirometric values were found in groups I and II compared to group III: lung function values were also lower in higher quartiles of latency and of cumulative exposure in these subjects. CONCLUSIONS: Progressive improvement in occupational hygiene in a developing country is likely to reduce the risk of non-malignant consequences of dust inhalation in asbestos miners and millers.

Adult↗
PubMed2005

Creatine supplementation during pulmonary rehabilitation in chronic obstructive pulmonary disease.

BACKGROUND: Skeletal muscle wasting and dysfunction are strong independent predictors of mortality in patients with chronic obstructive pulmonary disease (COPD). Creatine nutritional supplementation produces increased muscle mass and exercise performance in health. A controlled study was performed to look for similar effects in 38 patients with COPD. METHODS: Thirty eight patients with COPD (mean (SD) forced expiratory volume in 1 second (FEV(1)) 46 (15)% predicted) were randomised to receive placebo (glucose polymer 40.7 g) or creatine (creatine monohydrate 5.7 g, glucose 35 g) supplements in a double blind trial. After 2 weeks loading (one dose three times daily), patients participated in an outpatient pulmonary rehabilitation programme combined with maintenance (once daily) supplementation. Pulmonary function, body composition, and exercise performance (peripheral muscle strength and endurance, shuttle walking, cycle ergometry) took place at baseline (n = 38), post loading (n = 36), and post rehabilitation (n = 25). RESULTS: No difference was found in whole body exercise performance between the groups: for example, incremental shuttle walk distance mean -23.1 m (95% CI -71.7 to 25.5) post loading and -21.5 m (95% CI -90.6 to 47.7) post rehabilitation. Creatine increased fat-free mass by 1.09 kg (95% CI 0.43 to 1.74) post loading and 1.62 kg (95% CI 0.47 to 2.77) post rehabilitation. Peripheral muscle performance improved: knee extensor strength 4.2 N.m (95% CI 1.4 to 7.1) and endurance 411.1 J (95% CI 129.9 to 692.4) post loading, knee extensor strength 7.3 N.m (95% CI 0.69 to 13.92) and endurance 854.3 J (95% CI 131.3 to 1577.4) post rehabilitation. Creatine improved health status between baseline and post rehabilitation (St George's Respiratory Questionnaire total score -7.7 (95% CI -14.9 to -0.5)). CONCLUSIONS: Creatine supplementation led to increases in fat-free mass, peripheral muscle strength and endurance, health status, but not exercise capacity. Creatine may constitute a new ergogenic treatment in COPD.

Administration, Oral↗
PubMed2003

The pattern and timing of breathing during incremental exercise: a normative study.

Clinical evaluation of the pattern and timing of breathing during submaximal exercise can be valuable for the identification of the mechanical ventilatory consequences of different disease processes and for assessing the efficacy of certain interventions. Sedentary individuals (60 male/60 female, aged 20-80 yrs) were randomly selected from >8,000 subjects and submitted to ramp incremental cycle ergometry. Tidal volume (VT)/resting inspiratory capacity, respiratory frequency, total respiratory time (Ttot), inspiratory time (TI), expiratory time (TE), duty cycle (TI/Ttot) and mean inspiratory flow (VT/TI) were analysed at selected submaximal ventilatory intensities. Senescence and female sex were associated with a more tachypnoeic breathing pattern during isoventilation. The decline in Ttot was proportional to the TI and TE reductions, i.e. TI/Ttot was remarkably constant across age strata, independent of sex. The pattern, but not timing, of breathing was also influenced by weight and height; a set of demographically and anthropometrically based prediction equations are therefore presented. These data provide a frame of reference for assessing the normality of some clinically useful indices of the pattern and timing of breathing during incremental cycle ergometry in sedentary males and females aged 20-80 yrs.

Adult↗
PubMed2002

Home based neuromuscular electrical stimulation as a new rehabilitative strategy for severely disabled patients with chronic obstructive pulmonary disease (COPD).

BACKGROUND: Passive training of specific locomotor muscle groups by means of neuromuscular electrical stimulation (NMES) might be better tolerated than whole body exercise in patients with severe chronic obstructive pulmonary disease (COPD). It was hypothesised that this novel strategy would be particularly effective in improving functional impairment and the consequent disability which characterises patients with end stage COPD. METHODS: Fifteen patients with advanced COPD (nine men) were randomly assigned to either a home based 6 week quadriceps femoris NMES training programme (group 1, n=9, FEV(1)=38.0 (9.6)% of predicted) or a 6 week control period before receiving NMES (group 2, n=6, FEV(1)=39.5 (13.3)% of predicted). Knee extensor strength and endurance, whole body exercise capacity, and health related quality of life (Chronic Respiratory Disease Questionnaire, CRDQ) were assessed. RESULTS: All patients were able to complete the NMES training programme successfully, even in the presence of exacerbations (n=4). Training was associated with significant improvements in muscle function, maximal and endurance exercise tolerance, and the dyspnoea domain of the CRDQ (p<0.05). Improvements in muscle performance and exercise capacity after NMES correlated well with a reduction in perception of leg effort corrected for exercise intensity (p<0.01). CONCLUSIONS: For severely disabled COPD patients with incapacitating dyspnoea, short term electrical stimulation of selected lower limb muscles involved in ambulation can improve muscle strength and endurance, whole body exercise tolerance, and breathlessness during activities of daily living.

Aged↗
PubMed2001

Reference values for dynamic responses to incremental cycle ergometry in males and females aged 20 to 80.

Interpretation of incremental cardiopulmonary exercise tests (CPET) might be enhanced by considering the simultaneous rates of change of certain key variables, e.g., Delta oxygen uptake/Delta work rate (Delta VO(2)/Delta WR), Delta heart rate/Delta VO(2) (Delta HR/Delta VO(2)), Delta ventilation/Delta carbon dioxide production (Delta VE/Delta VCO(2)), and the linearized Delta tidal volume/Delta VE (Delta VT/Delta lnVE) relationships. However, there are no published age- and sex-dependent reference values for these relationships that were appropriately obtained in randomly selected subjects. We therefore prospectively evaluated 120 sedentary individuals (60 male, 60 female, age 20 to 80 yr) who were randomly selected from more than 8,000 subjects, and submitted to standard ramp-incremental CPET on an electronically braked cycle ergometer. We found that sex and age significantly influenced several of the dynamic relationships, in addition to anthropometric attributes (p < 0.05). A comprehensive set of linear prediction equations is provided; the limits of normality (at the 95% confidence level) differed substantially from previous recommendations based on single discrete values. These data therefore provide a frame of reference for assessing the normalcy of the response profiles of four standard indices of metabolic, cardiovascular, and ventilatory function during rapidly incremental cycle ergometry in sedentary males and females up to 80 yr of age.

Adult↗
PubMed2001

Peak VO2 correction for fat-free mass estimated by anthropometry and DEXA.

PURPOSE: Anthropometric (ANTHRO) and dual-energy x-ray absorptiometric (DEXA) estimates of total body and leg fat-free masses (FFM) were obtained in 77 randomly selected sedentary men and women, aged 20-80: intermethod limits of agreement and their clinical significance, as inferred from the differences on peak VO2 corrected for FFMANTHRO and FFMDEXA, were determined. METHODS: Limits of agreement were calculated as mean bias +/- 95% confidence intervals: peak VO2 at maximum cycle ergometry was related to FFMANTHRO and FFMDEXA by using both standard (y x x(-1)) and power function ratios (allometry). RESULTS: Data distribution of the ANTHRO-DEXA differences presented significant heteroscedasticity in both sexes, i.e., differences were proportional to the mean (P < 0.05). After logarithmic transformation, the mean bias +/- 95% limits of agreement were expressed as ratios (ANTHRO x DEXA(-1) x// error ratio): these corresponded to 0.95 x// 1.11 or 0.99 x// 1.15 for total body FFM and 0.90 x// 1.10 or 1.02 x// 1.07 for leg FFM in men and women, respectively. In addition, we found different allometric exponents for FFMANTHRO and FFMDEXA: the intermethod differences, therefore, increased after power function expression (P < 0.05). CONCLUSION: Discrepancies between ANTHRO and DEXA measurements of FFM depend on the magnitude of the estimate: differences are typically within 10 to 15%. Importantly, FFM-corrected peak VO2 values can vary according to the method chosen for body composition assessment, especially when allometry is used for peak VO2 correction. These results demonstrate that ANTHRO-DEXA differences in FFM estimation do have relevant practical consequences for the analysis of maximum aerobic capacity in nontrained humans.

Absorptiometry, Photon↗
PubMed2000

The effect of age on the power/duration relationship and the intensity-domain limits in sedentary men.

The time to fatigue (t) in response to high-intensity constant-load exercise decreases hyperbolically with increasing power (W), at least in active and younger individuals [i.e. (W - thetaF)t = W', where thetaF is the critical power asymptote and W' is the curvature constant]. Little is known, however, about the combined effects of age and sedentarity on these parameters. We therefore evaluated 17 non-trained males (9 aged 60-75 years and 8 aged below 30 years) who underwent ramp-incremental cycle ergometry and, on different days, 4 high-intensity constant-load tests to t. Compared to their younger counterparts, the older subjects presented significantly lower maximum oxygen uptake (i.e. the maximum value of oxygen uptake attained at the end of a progressive exercise with the subject exerting a presumably maximal effort, muVO2), estimated lactate threshold (VO2thetaL), VO2thetaF, and W' (P < 0.05). Interestingly, however, both VO2thetaL and VO2thetaF, when expressed as a percentage of muVO2, were higher in older than in younger men [61.8 (6.2)% versus 45.4 (4.6)% and 87.8 (7.3)% versus 79.0 (8.2)%, P < 0.05, respectively]. Therefore, age was associated with an increase in the relative magnitude of the "moderate", sub-thetaL exercise-intensity domain (+30.4%), mainly at the expense of the "very-heavy", supra-thetaF domain (-56%). Our results demonstrate that age and sedentarity are associated with: (1) marked reductions in both the aerobic (thetaF) and anaerobic (W') determinants of the W/t relationship, and (2) changes in either the absolute or relative magnitudes of the exercise-intensity domains. These findings are consistent with the notion that endurance-related parameters are less diminished with ageing than the maximal capacity, thereby mitigating the deleterious effects of senescence in the functional capacity.

Adult↗
PubMed2000

Oxygen cost for cycling as related to leg mass in males and females, aged 20 to 80.

In order to evaluate the determinants of the metabolic cost for cycle ergometry, we analyzed the relationship between VO2 and leg mass (LM) and total body mass (TBM) in 71 randomly-selected sedentary subjects (34 men), aged 20 to 80. Participants performed constant work rate (WR) tests at 0, 25, and 50 W (at 60 rpm) for 6 minutes in a randomized sequence: gross VO2, gross efficiency, and work efficiency were related to TBM and LM as assessed by dual energy x-ray absorptiometry. We found that gross VO2 and gross efficiency were more strongly related to LM than TBM but work efficiency values were independent of both (P>0.05). Significantly higher values of VO2TBM were found in subjects with large LM/TBM ratios and vice-versa; VO2/LM, however, did not change with anthropometric characteristics. Gross VO2 (mL/min) was predicted by a LM-based equation (10.6 [WR, W] + 16.8 [LM, kg] +75) with a mean error below 5%: this equation predicted the cost more accurately than previous TBM-based formulations (P<0.01). We conclude that leg mass actually provides the preferred frame of reference for predicting the oxygen cost for cycle ergometry at 60 rpm in sedentary subjects, independent of age or gender.

Absorptiometry, Photon↗
PubMed2000

Determinants of the exercise endurance capacity in patients with chronic obstructive pulmonary disease. The power-duration relationship.

To characterize the determinants of the power-duration (W-t) relationship in patients with chronic obstructive pulmonary disease (COPD), we evaluated 8 nonhypoxemic patients (FEV(1) = 1.27 +/- 0.26 L) and 10 healthy controls. After an initial maximum-incremental exercise test on cycle ergometer (peak), the subjects underwent four high-intensity constant-load tests to the limit of tolerance (t), each on different days. The W-t relationship was found to be hyperbolic in both groups. Absolute values of both the critical power asymptote (theta(F)) and the curvature constant (W') were lower in patients than in control subjects. However, when expressed as percentage of peak work rate theta(F) was significantly higher in patients compared with control subjects (81.8 +/- 3.3% versus 67.5 +/- 3.7%, respectively, p < 0.01). There were severe reductions in t in the patients that were consistently associated with higher breathlessness scores and V E/MVV ratios. Interestingly, all patients were able to sustain exercise at theta(F) for 20 min despite near-maximum physiological and subjective stresses. We conclude that the reductions of both parameters of the hyperbolic W-t relationship (theta(F) and W') in patients with COPD were due to the ventilatory constraints and their sensory consequences. Importantly, theta(F) separated a "sustainable" from a "nonsustainable" exercise-intensity domain: this parameter consistently occurred closer to peak work rate in patients than the healthy control subjects.

Aged↗
PubMed1999

Maximal aerobic power and leg muscle mass and strength related to age in non-athlethic males and females.

To investigate the relationships between the age-associated decline in peak oxygen uptake (peak VO2), leg muscle mass (LMM) and leg strength (LS) under the modulating effect of gender and level of physical activity (LPA, as assessed by questionnaire), we evaluated 71 sedentary subjects [males(M):females(F), 34:37], aged 20-80 years. Peak VO2 at maximum cycle ergometry was related to LMM (dual energy X-ray absorptiometry) and LS (isokinetic dynamometry) using both standard (y x x(-1)) and power function ratios (allometry). Absolute values of all variables were higher in males and declined with age (P < 0.01). Differences between the genders disappeared after peak VO2 x LS(-1.46(M)or -1.62(F)) adjustment but remained significant between peak VO2 LMM-(-0.51 (M)or -0.45(F)) and LS LMM- (-091(M) or -1.10(F)) corrected values. Allometric correction of peak VO2 and LS by LMM slowed their age-related declines; the flattening effect however, was more evident in the females. Interestingly, while no age-related decrement in peak VO2 LS(-1) was found, power function ratio values also declined with age, and at a slower rate in females. These findings are consistent with those obtained following a multiple regression analysis using LPA as an independent covariate (P < 0.01). We conclude that using adequate scaling methods and controlling by LPA: (1) no gender differences are observed in peak VO2 adjusted for LS, (2) loss of LS and LMM are important determinants of the age-associated reduction in physical fitness in both genders but (3) age per se has an LS- and LMM-independent influence on the functional decline, although this intrinsic effect of senescence is less pronounced in females.

Adult↗
PubMed1999

Short-term effects of aerobic training in the clinical management of moderate to severe asthma in children.

BACKGROUND: Aerobic training has a number of well known beneficial effects in both normal and asthmatic children. However, the impact of training on the clinical management of the underlying bronchial asthma remains controversial, particularly in the most severe patients. METHODS: Clinical evaluation, spirometric tests, symptom limited maximum exercise testing, and exercise challenge tests were performed in a group of children with stable moderate to severe asthma. Forty two patients (24 boys) aged 8-16 were evaluated twice: before and after supervised aerobic training (group 1, n = 26) and two months apart (untrained group 2, n = 16). RESULTS: Spirometric and maximal exercise variables in the initial evaluation were significantly reduced in group 1 (p < 0.05) but medication and clinical scores and the occurrence of exercise induced bronchospasm (EIB) did not differ between the two groups. Aerobic improvement with training (maximal oxygen uptake and/or anaerobic threshold increment > 10% and 100 ml) was inversely related to the baseline level of fitness and was independent of disease severity. Although the clinical score and the occurrence of EIB did not change after training, aerobic improvement was associated with a significant reduction in the medication score and the daily use of both inhaled and oral steroids (p < 0.05). CONCLUSIONS: Aerobic improvement with training in less fit asthmatic children is related to a short term decrease in the daily use of inhaled and oral steroids, independent of the severity of the disease.

Adolescent↗
PubMed1999

Prediction of metabolic and cardiopulmonary responses to maximum cycle ergometry: a randomised study.

All of the most widely-cited studies for the prediction of maximum exercise responses have utilized either volunteers or referred subjects. Therefore, selection bias, with overestimation of the reference values, is a likely consequence. In order to establish a set of predictive equations for the gas exchange, ventilatory and cardiovascular responses to maximum ramp-incremental cycle ergometry, this study prospectively evaluated 120 sedentary individuals (60 males, 60 females, aged 20-80), randomly-selected from >8,000 subjects. Regular physical activity pattern by questionnaire, body composition by anthropometry and dual energy X-ray absorptiometry (n = 75) and knee strength by isokinetic dynamometry were also assessed. Previously reported equations typically overestimated the subjects' peak oxygen uptake (p<0.05). Prediction linear equations for the main variables of clinical interest were established by backward stepwise regression analysis including: sex, age, knee extensor peak torque, bone-free lean leg mass, total and lean body mass, height, and physical activity scores. Reference intervals (95% confidence limits) were calculated: some of these values differed markedly from those formerly recommended. The results therefore might provide a more appropriate frame of reference for interpretation of the responses to symptom-limited ramp incremental cycle ergometry in sedentary subjects; i.e. those usually referred for clinical cardiopulmonary exercise tests.

Adult↗
PubMed1999

Reference values for lung function tests. I. Static volumes.

Static lung volume (LV) measurements have a number of clinical and research applications; however, no previous studies have provided reference values for such tests using a healthy sample of the adult Brazilian population. With this as our main purpose, we prospectively evaluated 100 non-smoking subjects (50 males and 50 females), 20 to 80 years old, randomly selected from more than 8,000 individuals. Gender-specific linear prediction equations were developed by multiple regression analysis with total lung capacity (TLC), functional residual capacity (FRC), residual volume (RV), RV/TLC ratio and inspiratory capacity (IC) as dependent variables, and with age, height, weight, lean body mass and indexes of physical fitness as independent ones. Simpler demographic and anthropometric variables were as useful as more complex measurements in predicting LV values, independent of gender and age (R2 values ranging from 0.49 to 0.78, P < 0.001). Interestingly, prediction equations from North American and European studies overestimated the LV at low volumes and underestimated them at high volumes (P < 0.05). Our results, therefore, provide a more appropriate frame of reference to evaluate the normalcy of static lung volume values in Brazilian males and females aged 20 to 80 years.

Adult↗
PubMed1999

Reference values for lung function tests. II. Maximal respiratory pressures and voluntary ventilation.

The strength of the respiratory muscles can be evaluated from static measurements (maximal inspiratory and expiratory pressures, MIP and MEP) or inferred from dynamic maneuvers (maximal voluntary ventilation, MVV). Although these data could be suitable for a number of clinical and research applications, no previous studies have provided reference values for such tests using a healthy, randomly selected sample of the adult Brazilian population. With this main purpose, we prospectively evaluated 100 non-smoking subjects (50 males and 50 females), 20 to 80 years old, selected from more than 8,000 individuals. Gender-specific linear prediction equations for MIP, MEP and MVV were developed by multiple regression analysis: age and, secondarily, anthropometric measurements explained up to 56% of the variability of the dependent variables. The most cited previous studies using either Caucasian or non-Caucasian samples systematically underestimated the observed values of MIP (P < 0.05). Interestingly, the self-reported level of regular physical activity and maximum aerobic power correlates strongly with both respiratory and peripheral muscular strength (knee extensor peak torque) (P < 0.01). Our results, therefore, provide a new frame of reference to evaluate the normalcy of some useful indexes of respiratory muscle strength in Brazilian males and females aged 20 to 80.

Adult↗
PubMed1999

Reference values for lung function tests. III. Carbon monoxide diffusing capacity (transfer factor).

Carbon monoxide diffusing capacity (DLCO) or transfer factor (TLCO) is a particularly useful test of the appropriateness of gas exchange across the lung alveolocapillary membrane. With the purpose of establishing predictive equations for DLCO using a non-smoking sample of the adult Brazilian population, we prospectively evaluated 100 subjects (50 males and 50 females aged 20 to 80 years), randomly selected from more than 8,000 individuals. Gender-specific linear prediction equations were developed by multiple regression analysis with single breath (SB) absolute and volume-corrected (VA) DLCO values as dependent variables. In the prediction equations, age (years) and height (cm) had opposite effects on DLCOSB (ml min-1 mmHg-1), independent of gender (-0.13 (age) + 0.32 (height) - 13.07 in males and -0.075 (age) + 0.18 (height) + 0.20 in females). On the other hand, height had a positive effect on DLCOSB but a negative one on DLCOSB/ VA (P < 0.01). We found that the predictive values from the most cited studies using predominantly Caucasian samples were significantly different from the actually measured values (P < 0.05). Furthermore, oxygen uptake at maximal exercise (VO2max) correlated highly to DLCOSB (R = 0.71, P < 0.001); this variable, however, did not maintain an independent role to explain the VO2max variability in the multiple regression analysis (P > 0.05). Our results therefore provide an original frame of reference for either DLCOSB or DLCOSB/VA in Brazilian males and females aged 20 to 80 years, obtained from the standardized single-breath technique.

Adult↗