Cardiopulmonary Exercise Testing with Elastic Resistance: A New Reproducible Proposal for Determination of Ventilatory Thresholds and Maximum Oxygen Consumption.

To propose a new Cardiopulmonary Exercise Test with Elastic Resistance (CPxEL) and compare the physiological responses to conventional cardiopulmonary exercise test (CPx) performed on a treadmill. In addition, we tested the reproducibility of the CPxEL. Twenty-four physically active participants completed the CPx (first session) and CPxEL twice (second and third sessions) interspersed by seven days. A treadmill protocol with increments of 1km·h-1 every minute until exhaustion was used in CPx. The CPxEL consisted of performing alternating steps back-and-forth against an elastic resistance attached to a belt and an incremental protocol with 1 stage (S) per minute following a cadence of 200 bpm controlled by a metronome in an 8-stage rubber mat. First analysis: first ventilatory threshold (VT1) occurred at 69.7% and 75.3% of maximal heart rate (HRmax) and 53.5% and 65.7% of maximal oxygen consumption (V̇O2max). Second VT (VT2) occurred at 93.3% and 96.8% of the HRmax and 87.0% and 96.9% of V̇O2max for CPx and CPxEL, respectively. At exhaustion, V̇O2max, perceived exertion (BORG-CR10 and OMNI-RES EB), and test duration presented lower values for CPxEL (P < 0.05). Second analysis: VT1 occurred at warm-up (S0) (P = 0.731), VT2 occurred at S5 (P = 0.912), and the exhaustion occurred at S6 and S7 (P = 0.271) for CPxEL and retest, respectively. The intraclass correlation coefficient (ICC) for V̇O2max was 0.921 and for HRmax was 0.930. The CPxEL has good test-retest reproducibility and represents a possible and interesting add-on to determine maximal oxygen consumption, maximal heart rate, and second ventilatory threshold without using traditional ergometers.

Supervised walking improves cardiorespiratory fitness, exercise tolerance, and fatigue in women with primary Sjögren's syndrome: a randomized-controlled trial.

OBJECTIVE: The aim of this study was to evaluate the safety and effectiveness of a supervised walking program in women with primary Sjögren's syndrome (pSS). METHODS: Forty-five sedentary women fulfilling the American European Consensus Criteria for pSS were randomized to a training group (TG, n = 23) or control group (CG, n = 22). Patients in the TG were submitted to supervise walking three times a week for 16 weeks. The patients of the CG were instructed to not perform any kind of regular physical exercise. Physical fitness [maximum oxygen uptake (VO2max) and distance], EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI), hematological tests, and Medical Outcomes Study 36 (SF-36) were assessed at baseline and week 16. In addition, EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI), Functional Assessment of Chronic Illness Therapy Fatigue Subscale (FACIT-fatigue), and Beck Depression Inventory (BDI) were measured prior to intervention, after 8 and 16 weeks. Patient global assessment of response to therapy was completed at the final assessment. An intent-to-treat analysis was performed. RESULTS: After 16 weeks, the mean change of VO2max (ml/kg/min), distance, and FACIT-fatigue were higher in the TG than in the CG (p = 0.016, p = 0.043 and p = 0.030, respectively). Improved cardiorespiratory fitness was associated with improvements in fatigue scores and physical components of quality of life (SF-36). Furthermore, improved fatigue scores were associated with reduced depression and improvements in the physical and mental components of SF-36. Overall, 95.4% of patients in the TG rated themselves as clinically improved versus 62% of the patients in the CG (p = 0.049). There was no flare in disease activity and no serious adverse events with exercise. CONCLUSIONS: This supervised walking program was demonstrated to be feasible and safe with improvements in cardiorespiratory fitness, exercise tolerance, fatigue, and patient perception of improvement in pSS patients. TRIAL REGISTRATION: Clinical Trials.gov ID, number NCT02370225.

Heart rate at 4 s after the onset of exercise in endurance-trained men.

It has been suggested that the increase in heart rate (HR) at the onset of exercise is caused by vagal withdrawal. In fact, endurance runners show a lower HR in maximum aerobic tests. However, it is still unknown whether endurance runners have a lower HR at 4 s after the onset of exercise (4th-sec-HR). We sought to measure the HR at the onset of the 4 s exercise test (4-sET), clarifying its relationship to heart rate variability (HRV), spectral indices, and cardiac vagal index (CVI) in endurance runners (ER) and healthy untrained controls (CON). HR at 4th-sec-HR, CVI, and percent HR increase during exercise were analyzed in the 4-sET. High frequency spectrum (HF-nu), low frequency spectrum (LF-nu), and low frequency/high frequency band ratio (LF/HF) were analyzed from the HRV. ER showed a significantly higher HF, and both a lower LF and LF/HF ratio compared with the CON. ER presented a significantly lower 4th-sec-HR, although neither CVI nor HR increases during exercise were statistically different from the CON. In conclusion, ER presented a lower 4th-sec-HR secondary to increased vagal influence over the sinus node. CVI seems to be too weak to use for discriminating individuals with respect to the magnitude of HR vagal control.

Active and sedentary behaviours in children aged 7 to 10 years old: the urban and rural contexts, Brazil.

BACKGROUND: Although the effects of physical activity (PA) on health and wellness are well-established, incorporating sedentary behaviours in the daily lives of populations from high- and medium-income countries is becoming increasingly common. Regardless of other factors, the area of residence can influence the physical activity level and sedentary behaviours. The aim of this study was to identify and analyse active and sedentary behaviours and factors associated with physical activity in two different geographical areas in south-eastern Brazil. METHODS: 1.770 schoolchildren aged 7-10 years old were studied. Parents or caregivers completed a validated questionnaire on PA and sedentary behaviours. Screen time (ST) was calculated from the time spent watching television, playing video games and using the computer. The level of active PA (>300 minutes per week) was identified and compared between the areas of study. Parametric and non-parametric tests and Poisson regression model with robust variance were used for statistical analysis. RESULTS: Compared to schoolchildren from the urban area, those from the rural area showed a higher percentage of compliance with the PA recommendations (87 vs. 69.7%) and screen time <2 h (34.8 vs. 18.8%) and less participation in supervised PA. Active commuting to school was more common among schoolchildren from urban areas, although using a bicycle was more common in rural areas. The characteristics of children who do not meet the recommended weekly PA are as follows: being female, living in urban areas, being overweight, not using video games or performing supervised PA. Total ST as well as daily use of television and the computer was not associated with physical activity level in the present sample. Participation in supervised physical activities in both areas was found to increase the prevalence of being active in the areas studied. CONCLUSIONS: The results of the present study suggest that while schoolchildren from rural areas are more active and spend less time on sedentary activities than those from the urban area, the time spent in sedentary behaviors, such as watching television, playing video games and using the computer, is high in both contexts, and it is not associated with physical activity recommendation compliance.

Acute Cardiopulmonary Response of High-Intensity Interval Training with Elastic Resistance vs. High-Intensity Interval Training on a Treadmill in Healthy Adults.

This study aims to describe and compare cardiopulmonary and subjective responses during high-intensity interval training with elastic resistance (EL-HIIT) and traditional high-intensity interval training (HIIT) sessions. Twenty-two healthy adults (27.6 ± 4.4 years) performed an EL-HIIT and a HIIT protocol consisting of 10 × 1 min at ~85% V·O2max prescribed by cardiopulmonary-specific tests. Pulmonary parameters, heart rate (HR), blood lactate, and rate of perceived exertion (RPE) were measured during exercise. Paired t-test and Cohen's d effect size were used to compare peak and average values. Two-way repeated measures ANOVA and mixed model with Bonferroni's post hoc test were used to compare each bout during the session. The EL-HIIT session showed higher peak and average values of HR, ventilation (V·E), relative and absolute oxygen uptake (V·O2), carbon dioxide production (V·CO2), and RPE than HIIT (p < 0.05). The effect size (ES) comparing HIIT and EL-HIIT was large for HR, V·E, and lactate (≥0.8) in peak values. Comparing each bout between HIIT and EL-HIIT, no difference was found in peak values (p > 0.05) during the session (excluding baseline, warm-up, and recovery). EL-HIIT presented a more pronounced cardiopulmonary and subjective response than HIIT.

A Cardiopulmonary Exercise Testing for Prescribing High-Intensity Interval Training Sessions with Elastic Resistance.

This study aims to analyze the agreement of cardiopulmonary variables between a cardiopulmonary exercise test with elastic resistance (CPxEL) and high-intensity interval exercise with elastic resistance (EL-HIIE). METHODS: Twenty-two physically independent participants were recruited. Visit one consisted of conducting a health survey and anthropometric assessment. On visit two, the participants performed CPxEL. After seven days, on visit three, the participants performed EL-HIIE. The CPxEL was carried out on a rubber mat demarcated by lines representing eight stages. The test consisted of alternating back and forth steps against elastic resistance. The increments were performed at a rate of one stage per minute, following a cadence controlled by a metronome calibrated by beats per minute (bpm). The EL-HIIE was performed at the stage corresponding to an intensity of ~85% VO2max, as determined by CPxEL. The EL-HIIE consisted of 10 × 1 min (work):1 min (passive rest), with a cadence of 200 bpm. Cardiopulmonary parameters, heart rate (HR), and oxygen consumption (VO2) were measured during exercise. Bland-Altman was applied to analyze the agreement between the HR and VO2 found in EL-HIIE and the values prescribed by CPxEL (~85-90% VO2max). RESULTS: The HRpeak and VO2peak in the EL-HIIE showed good agreement with the VO2CPxEL and HRCPxEL values, showing an average difference of (-1.7 mL·kg-1·min-1) and (0.3 bpm). CONCLUSIONS: The results of the present study demonstrate the agreement of cardiopulmonary variables between the CPxEL and the EL-HIIE. Therefore, for a more specific prescription of EL-HIIE intensity, CPxEL can be used.

Nutritional extremes among school children in a rural Brazilian municipality.

INTRODUCTION: Latin America is undergoing rapid demographic and nutritional transitions with the accompanying tendency to overweight as is common in countries emerging from poverty. In Brazil, changes due to the nutritional transition have affected the whole population, both urban and rural. Overweight in a large number of Brazilian children is one of the greatest public policy challenges. The objective of this 2009-2010 study was to estimate the prevalence of nutritional extremes among children from 7 to 10 years of age in a rural municipality on the state of Espírito Santo, Brazil. METHODS: The sample consisted of 901 school children. Socio-demographic (sex, school location, age and skin color) and anthropometric (weight and height) data were collected, as well as information on eating habits (breakfast, number of meals and presence of a companion during meals). The nutritional status was classified according to BMI per age with the cut-off points: BMI for age < 3rd percentile = underweight and BMI per age > 97th percentile = obesity. RESULTS: A prevalence of 3.4% underweight and 5% obesity was observed, the latter higher in urban areas (p<0.05). Living in an urban area and the habit of eating four or fewer meals/day were associated with obesity among children. Among urban located children 7.5% obesity was found, approximately twice that of rural children. CONCLUSION: Underweight has been regressing, possibly due to improvements in access to health and better living conditions, even in rural areas. However obesity was associated with this in the urban location of the area studied. Children who studied and lived in rural areas showed a lower prevalence of obesity, possibly due to lower socioeconomic conditions and more intense physical activity in their daily activities. The habit of eating four or fewer meals was associated with obesity. This could be explained by the alteration it causes to biological mechanisms. The promotion of physical activity is proposed, mainly in urban areas, and nutritional education aimed at improve eating habits in both urban and rural areas.

Is There Agreement and Precision between Heart Rate Variability, Ventilatory, and Lactate Thresholds in Healthy Adults?

This study aims to analyze the agreement and precision between heart rate variability thresholds (HRVT1/2) with ventilatory and lactate thresholds 1 and 2 (VT1/2 and LT1/2) on a treadmill. Thirty-four male students were recruited. Day 1 consisted of conducting a health survey, anthropometrics, and Cardiopulmonary Exercise Test (CPx). On Day 2, after 48 h, a second incremental test was performed, the Cardiopulmonary Stepwise Exercise Test consisting of 3 min stages (CPxS), to determine VT1/2, LT1/2, and HRVT1/2. One-way repeated-measures ANOVA and effect size (ηp2) were used, followed by Sidak's post hoc. The Coefficient of Variation (CV) and Typical Error (TE) were applied to verify the precision. Bland Altman and the Intraclass Correlation Coefficient (ICC) were applied to confirm the agreement. HRVT1 showed different values compared to LT1 (lactate, RER, and R-R interval) and VT1 (V̇E, RER, V̇CO2, and HR). No differences were found in threshold 2 (T2) between LT2, VT2, and HRVT2. No difference was found in speed and V̇O2 for T1 and T2. The precision was low to T1 (CV > 12% and TE > 10%) and good to T2 (CV < 12% and TE < 10%). The agreement was good to fair in threshold 1 (VT1, LT1, HRVT1) and excellent to good in T2 (VT1, LT1, HRVT1). HRVT1 is not a valid method (low precision) when using this protocol to estimate LT1 and VT1. However, HRVT2 is a valid and noninvasive method that can estimate LT2 and VT2, showing good agreement and precision in healthy adults.

Profile of blood pressure and glycemic responses after interval exercise in older women attending (in) a public health physical activity program.

BACKGROUND: and purpose: Interval exercise causes a positive impact on health status. Our aim was to evaluate the effects of a feasible and low-cost interval exercise on blood pressure and glycemic responses in people with controlled systemic arterial hypertension. METHODS: Thirteen women with hypertension (HG; age: 60.2 ± 2.8 years) and 11 without hypertension (CG; age: 54.4 ± 3.8 years) were recruited. Groups performed one session of interval exercise with elastic resistance (10 series of 1:1 min/effort:rest). RESULTS: There were slight reductions of absolute systolic blood pressure values for HG at 10, 30, and 60 min (4, 9, and 8 mmHg, respectively) at post-compared to pre-exercise. Glycemia was reduced (respectively, 17.6%, 17.6%, 19.4%, and 23.1%; p < 0.05) at pre-exercise vs. 0 min and 10, 30, and 60 min post-exercise for the HG. CONCLUSION: A single session of a feasible and low-cost interval exercise modifies and promotes significant clinical effects in blood pressure and glycemic levels in female older adults with and without hypertension.

The association between cardiorespiratory fitness and cardiovascular risk in adolescents.

OBJECTIVE: Maximum oxygen uptake is emerging as the measure of preference for expressing cardiorespiratory fitness for the purposes of surveys of physical activity, due to its greater objectivity and lower propensity to errors. Studies indicate that this measure is better correlated with cardiovascular diseases. This paper proposes to relate cardiovascular risk factors in adolescents with their level of cardiorespiratory fitness. METHODS: The study enrolled 380 schoolchildren, 177 boys and 203 girls (10 to 14 years old), who were divided into two groups according to their cardiorespiratory fitness. Anthropometric assessment was carried out, hemodynamic measurements (arterial pressure and heart rate) were taken, cardiopulmonary exercise testing was performed and biochemical tests were run (triglycerides, total and partial cholesterol). RESULTS: Among the boys, significant differences were observed between boys defined as "weak" and those classed as "not weak" in terms of baseline heart rate, maximum oxygen uptake, body mass index and triglycerides. Among the girls, significant differences were detected between baseline heart rates, maximum oxygen uptake and body mass indices. In both sexes, the group classified as "weak" exhibited a significantly greater number of overweight individuals that the "not weak" group (chi2 = 25.242; p = 0.000; chi2 = 12.683; p = 0.000, for boys and girls, respectively). A significant association between cardiorespiratory fitness and triglycerides (chi2 = 3.944; p = 0.047) was observed among the boys only. CONCLUSIONS: A low level of cardiorespiratory fitness appears to have a negative influence on cardiovascular risk factors among adolescents, especially with relation to overweight in both sexes and to biochemical profile in the male sex, providing evidence of the need for early preventative interventions.

Maximum oxygen uptake in adolescents as measured by cardiopulmonary exercise testing: a classification proposal.

OBJECTIVE: The identification of populational levels of maximum oxygen uptake (VO(2max)) is an aid to studies that propose to relate physical fitness to cardiovascular risk, and also for prescribing exercise and analyzing the effects of training. To date, there is no information with which this parameter can be classified in samples of adolescents from the Brazilian population. This study is, therefore, the first to propose the determination of mean VO(2max) levels in a sample of the Brazilian population. METHODS: A sample of 380 schoolchildren (177 boys and 203 girls, aged 10 to 14 years) was selected at random from public schools in Vitória, ES. After anthropometric assessment they underwent cardiopulmonary exercise testing, VO(2max) was measured directly and results were classified according to quintiles calculated from the study sample. RESULTS: The mean VO(2max) values observed ranged from 42.95 to 49.55 mL x kg(-1) x min(-1) for boys and from 36.76 to 38.29 mL x kg(-1) x min(-1) for girls. CONCLUSION: This paper proposes mean VO(2max) ranges as a classification parameter for cardiorespiratory fitness, in addition to contributing to a definition of normal values for the Brazilian population. This classification will also be of use for establishing cutoff points in future studies.

Cardiorespiratory fitness level influences the ventilatory threshold identification / Nível de aptidão cardiorrespiratória influencia a identificação do limiar ventilatório

ABSTRACT We aimed to analyze the influence of cardiorespiratory fitness (CRF) on ventilatory threshold identification (VT1) using the Ventilatory Equivalents (VEq) and V-slope methods. Twenty-two male runners (32.9 ± 9.4 years) were divided into two groups: G1 - group with less cardiorespiratory fitness (CRF: VO2max 40 to 51 ml·kg-1·min-1) and G2 - higher CRF (G1; VO2max ?56,4 to 72 ml·kg-1·min-1) divided by the 50th percentile. An incremental cardiopulmonary exercise test was applied to identify VT1 using VEq and V-slope methods to compare heart rate (HR), oxygen consumption (VO2), and speed. Two-way ANOVA was used to compare HR, VO2, and speed (groups vs. methods). The Effect size was calculated using Cohen's d. The intraclass correlation coefficient, variation coefficient, typical error, and Bland Altman were applied to verify reliability and agreement. No significant differences (p < 0.05) were found between methods for G1 (VO2, HR, and speed), and Bland Altman showed good agreement (mean difference: VO2 0.35ml·kg-1·min-1; HR 2.58bpm; speed 0.33km·h-1). However, G2 presented statistical differences between methods (VO2 and speed) and a more significant mean difference (VO2 2.68ml·kg-1·min-1; HR 6.87 bpm; speed 0.88km·h-1). The small effect size was found in G1 between methods (VO2: 0.06; speed: 0.20; HR: 0.14), and small and moderate effects were found in G2 between methods (VO2: 0.39; speed: 0.43; HR: 0.51). In conclusion, runners with lower CRF have a better agreement for the V-slope and VEq methods than those with a higher CRF.

RESUMO O objetivo deste estudo foi analisar a influência do nível de aptidão cardiorrespiratória (ACR) entre os métodos Equivalente Ventilatório (VEq) e V-slope para determinação do Limiar Ventilatório 1 (LV1). 22 homens corredores (32,9 ± 9,4 anos) foram divididos em dois grupos: G1 - grupo com menor aptidão cardiorrespiratória (ACR:VO2máx 40 a 51 ml·kg-1·min-1) e G2 - maior ACR (VO2máx 56,4 a 72 ml·kg-1·min-1), divididos pelo percentil 50. Foi aplicado um teste incremental cardiopulmonar para identificar o LV1 através dos métodos VEq e V-slope, comparando as seguintes variáveis: Frequência Cardíaca (FC), Consumo de Oxigênio (VO2) e velocidade. Para comparações entre FC, VO2 e velocidade (grupos vs. métodos) empregou-se ANOVA de duas vias. O tamanho do efeito foi calculado utilizando d'Cohen. Para verificar a confiabilidade e a concordância, foram aplicados o coeficiente de correlação intraclasse, coeficiente de variação, erro típico e Bland Altman. Não foram encontradas diferenças significativas (p < 0,05) entre métodos para G1 (VO2, FC e velocidade) e Bland Altman revelou boa concordância (diferença média: VO2 0,35ml·kg-1·min-1; FC 2,58bpm; velocidade 0,33km·h-1). Contudo, G2 apresentou diferenças estatísticas entre métodos (VO2 e velocidade) e maior diferença média (VO2 2,68ml·kg-1·min-1; FC 6,87 bpm; velocidade 0,88km·h-1). Tamanho de efeito pequeno foi encontrado no G1 entre os métodos (VO2: 0,06; velocidade: 0,20; FC: 0,14) e efeitos Pequenos e moderados foram encontrados no G2 entre os métodos (VO2: 0,39; velocidade: 0,43; FC: 0,51). Conclui-se que corredores com menor ACR apresentam melhor concordância para os métodos V-slope e VEq em comparação aqueles com maior ACR.

Oxygen consumption and heart rate obtained in a ramp protocol are equivalent during exercise session of rectangular loading at ventilatory thresholds for athletes / Consumo de oxigênio e frequência cardíaca obtidos em um protocolo de rampa são equivalentes durante sessão de exercícios de carga retangular nos limiares ventilatórios para atletas

Abstract Training near or at ventilatory threshold (VT) is an adequate stimulus to improve the thresholds for sedentary subjects, but a higher intensity is necessary for conditioned subjects. The choice of cardiopulmonary exercise testing (CPx) protocol has an influence on VTs identification and can reduce their reliability for exercise prescription. This study tested if VO2 and heart rate (HR) corresponding to first (VT1) and second ventilatory threshold (VT2) determined during a ramp protocol were equivalent to those observed in rectangular load exercises at the same intensity in runners elite athletes (EA) and non-athletes (NA). Eighteen health subjects were divided into two groups: EA (n = 9, VO2max 68.6 mL·kg-1·min-1) and NA (n = 9, VO2max 47.2 mL·kg-1·min-1). They performed CPx and 48h and 96h later, a continuous running lasting 1 h for VT1 and until exhaustion for VT2. The results showed that EA at VT1 session, presented delta differences for VO2 (+9.1%, p = 0.125) vs. NA (+20.5%, p = 0.012). The Bland-Altman plots for VT1 presented biases of (4.4 ± 6.9) and (5.5 ± 5.6 mLO2·kg-1·min-1) for AE and NA, respectively. In VT2, the VO2 and HR of the NA showed biases of (0.4 ± 2.9 mLO2·kg-1·min-1) and (4.9 ± 4.2 bpm). The ramp protocol used in this study was inappropriate for NA because it underestimates the values of VO2 and HR at VT1 found in the rectangular load exercise. The HR showed good agreement at VT2 with CPx and may be a good parameter for controlling exercise intensity.

Resumo O treinamento no limiar ventilatório (LV) é um estímulo adequado para melhorar os limiares em indivíduos sedentários, entretanto uma maior intensidade é necessária para indivíduos condicionados. A escolha do protocolo de teste de exercício cardiopulmonar (CPx) tem influência na identificação dos LV e pode reduzir sua confiabilidade na prescrição do exercício. Este estudo testouse o VO2 e a frequência cardíaca (FC) correspondentes ao primeiro (LV1) e segundo limiar ventilatório (LV2) determinados durante um protocolo de rampa foram equivalentes àqueles observados em exercícios de carga retangular nas mesmas intensidades em atletas corredores de elite (AE) e não atletas (NA). Dezoito homens saudáveis foram divididos em dois grupos: AE (n = 9, VOmax 68,6 mL·kg-1·min-1) e NA (n = 9, VO2max 47,2 mL·kg-1·min-1). Eles realizaram CPx e 48h e 96h depois, uma corrida contínua com duração de 1 h para o LV1 e até a exaustão para o LV2. O grupo AE na sessão LV1, apresentou diferenças de delta para VO2(+ 9,1%, p = 0,125) vs. NA (+ 20,5%, p = 0,012). Bland-Altman para LV1 apresentaram vieses de (4,4 ± 6,9) e (5,5 ± 5,6 mLO2·kg-1·min-1) para AE e NA, respectivamente. No LV2, o VO2 e a FC do NA apresentaram vieses de (0,4 ± 2,9) mLO2·kg-1·min-1 e (4,9 ± 4,2) bpm. O protocolo de rampa utilizado foi inadequado para NA pois subestima os valores de VO2 e FC em LV1 encontrados no exercício de carga retangular. A FC exibiu boa concordância no LV2 e pode ser um bom parâmetro para controlar a intensidade do exercício.

Long-term intense resistance training in men is associated with preserved cardiac structure/function, decreased aortic stiffness, and lower central augmentation pressure.

OBJECTIVE: There have been contradictory reports regarding resistance exercise and central arterial compliance. The American Heart Association has recommended its use in preventing/treating cardiovascular diseases. We examined the effects of long-term endurance running and intense resistance training on central hemodynamics, compared with healthy control (CON). METHODS: Sixty-nine male participants, 25-50 years [19 intense resistance trained (IRT) group, 21 endurance runners, and 29 CON] were investigated by radial tonometry-pulse wave analysis, pulse wave velocity (PWV), and echocardiogram. Data were expressed as mean ± SE (median). Differences were tested by analysis of variance and analysis of covariance was used to adjust for confounding variables. RESULTS: There were no differences among groups regarding age, height (Ht), brachial and central blood pressure. Resting heart rate (HR) was lower and high-density lipoprotein cholesterol (HDL-C) higher in endurance runners. Weight, peripheral pulse pressure, and pulse pressure amplification were higher and HDL-C lower in the IRT group. Left ventricular mass and creatine phosphokinase were higher in trained participants. Relative wall thickness was similar among groups. The ratio of the velocity of peak E and A waves (E/A) was higher and PWV significantly lower in endurance runners (7.2 ± 0.14 m/s) and IRT (7.5 ± 0.14 m/s) as compared with CON (8.2 ± 0.16 m/s) even after adjustments for age, Ht, HR and mean arterial pressure (MAP), or mean systolic pressure. Differences in central augmentation pressure (cAP) adjusted for age, height, systolic or MAP, PWV, and HR (IRT equal to 0.08 ± 0.9, CON equal to 3.4 ± 0.9 and endurance running equal to 3.6 ± 1) were no longer significant after further adjustments to aortic diameter or weight. CONCLUSION: Long-term resistance training in men is associated with preserved cardiac structure/function, decreased aortic stiffness, and lower cAP.

Level of performance and stability of cardiopulmonary variables in the intensity of the ventilatory anaerobic threshold

AIM: The aim of this study was to describe the behavior of different cardiopulmonary variables in exercise session with constant running speed, corresponding to the intensity of ventilatory anaerobic threshold and identifying the steady state in a different level of performance. METHODS: A cross-sectional study with nine elite athletes (31 ± 5.7 years, 1.7 ± 0.05 meters and O2max 68.6 ± 3.2 mL·kg-1·min-1) and nine non-athletes (32 ± 10 years, 1.8 ± 0.1 meters and O2max 47.2± 4.4 mL·kg-1·min-1). Two visits to the laboratory have been conducted. Firstly, cardiopulmonary exercise testing until voluntary exhaustion took place to identify ventilatory thresholds and maximum oxygen consumption (O2max) and secondly, there was a running session for 1 hour in ventilatory anaerobic threshold speed, with continuous measurement of exhaled gases. A range of 5% (∆5%) for VO2 and PetCO2 was used; 5.5% (∆5.5%) for VE and 3% (∆3%) for respiratory exchange ratio (RER) and one-way ANOVA with statistical significance of p ≤ 0.05 to identify the steady state of results. RESULTS: A session with constant speed related to ventilatory anaerobic threshold intensity showed similarity in the steady state of ventilatory variables except for RER in the NA group (p ≤ 0.05). CONCLUSION: It was possible to identify the steady state from ventilatory variables related to ventilatory anaerobic threshold intensity that occurred independently of the physical performance level.(AU)

Respostas cardiopulmonares agudas ao exercício com kettlebell / Acute cardiopulmonary responses to kettlebell exercise / Respuestas cardiopulmonares agudas al ejercicio con kettlebell

Resumo Com o objetivo de comparar o consumo de oxigênio (VO2) e a frequência cardíaca (FC) alcançados nos exercício swing e clean com kettlebell (KB), em relação ao máximo e ao limiar anaeróbio ventilatório (LAV), foram avaliadas 12 mulheres treinadas em KB (idade 31 ± 7; %G 21 ± 7; VO2máx. 43,5 ± 6,8; FCmáx. 183 ± 7). Foram feitos o teste cardiopulmonar em esteira ergométrica (TCPE) e dois testes de cinco minutos com KB. Não houve diferença significativa entre swing e clean para qualquer das variáveis. O VO2 atingiu valores acima do encontrado no LAV do TCPE, tanto para o swing quanto para o clean, 75% e 77% do VO2máx.(ml.kg-1.min-1) e 93% e 95% da FCmáx (bpm), respectivamente. Os resultados sugerem uma exigência aguda do sistema aeróbio suficiente para possíveis adaptações cardiovasculares em resposta aos exercícios com KB.

Abstract In order to compare the oxygen consumption (VO2) and heart rate (HR) reached the swing exercise and clean with Kettlebell (KB), relative to the maximum and the ventilatory anaerobic threshold (VAT), were evaluated 12 women trained in KB (Age 31 ± 7; %BF 21 ± 7; VO2máx. 43,5 ± 6,8; HRmax 183 ± 7). Cardiopulmonary exercise testing on a treadmill (CPET) and two five-minute tests were performed with KB. There was no significant difference between swing and clean for the variables. VO2 reached values higher than those found in LAV CPET for both the swing and to the clean, 75% and 77% of VO2max. (ml.kg-1.min-1) and 93% to 95% HRmax (bpm), respectively. The results suggest an acute requirement of sufficient aerobic system for possible cardiovascular adaptations in response to exercise with KB.

Resumen Con el fin de comparar el consumo de oxígeno (VO2) y la frecuencia cardíaca (FC) alcanzados en el ejercicio de swing y clean con kettlebell (KB) en relación con el umbral anaeróbico ventilatorio (UAV) y máximo, se evaluó a 12 mujeres entrenadas en KB (edad: 31 ± 7; %G: 21 ± 7; VO2máx.: 43,5 ± 6,8; FCmáx.: 183 ± 7). Se fazeron una prueba de esfuerzo cardiopulmonar (PECP) en cinta sin fin y dos pruebas de 5 minutos con KB. No hubo diferencia considerable entre swing y clean en ninguna de las variables. El VO2 alcanzó valores superiores a los que se hallaron en UAV y PECP, tanto en swing como en clean, es decir, el 75 y el 77% de VO2máx. (ml.kg-1.min-1) y el 93 y el 95% de FCmáx. (lpm), respectivamente. Los resultados sugieren un fuerte requerimiento del sistema aeróbico, suficiente para posibles adaptaciones cardiovasculares en respuesta al ejercicio con KB.

Heart rate as an indicator for exercise prescription for normal, overweight, and obese adolescents

This study aimed to investigate the relationship between heart rate (HR) predicted and VO2max using a CPET (cardiopulmonary exercise testing) among normal weight, overweight, and obese adolescents. The sample comprised 299 adolescents (142 boys), from Vitória (ES, Brazil), aged 10-14 years (12.6±1.4). Adolescents were classified into normal weight (n=236), overweight (n=34), and obese (n=29). Adolescents were subjected to a CPET ramp protocol on a treadmill. It was observed that the reserve heart rate (HRres) was similar to the maximum recommended oxygen uptake (VO2) for the maintenance and improvement of cardiorespiratory fitness. It was also observed that HRres can be used to control the intensity of exercise sessions in physical education classes independent of weight status. In conclusion, the relationship between the HR and VO2 for adolescents is linear, allowing the level of intensity to be determined by the HRres proportion related with the correspondent %VO2max levels of intensity, according to BMI-for-age categories

Vo2max estimadoppor equações preditivas apresena baixa concordância com o obtiido pelo teste cardiopulmonar - padrão ouro / Vo2maxestimated by predictive equatios presents low concordance withh that obtained by cardiopulmonary test - gold standard

RESUMOO objetivo foi avaliar a concordância entre mensurações do VO2maxobtidas em teste cardiopulmonar de exercício versus obtidas por equações preditivas. Homens (21-55 anos) foram agrupados em praticantes de musculação (PM; n=31) e corridas (PC; n=28) e não praticantes (SE; n=35). Testou-se 5 equações, uma delas elaborada a partir de amostra brasileira. A concordância foi avaliada por Bland-Altman e as correlações pelo coeficiente de correlação de Pearson (r). Os r entre medida padrão ouro vs. equações ficaram entre 0,27 a 0,75, com p<0,05 para a maioria. Entretanto, as concordâncias foram baixas. Na equação obtida em brasileiros, os valores menos concordantes foram, em ordem: SE, PM e PC; nas demais equações foram: PC, PM e SE. As piores estimativas foram para VO2maxmais elevados, principalmente >40 mL.kg-1.min1. Conclui-se que as equações preditivas avaliadas nesse estudo geraram medidas de baixa concordância quando comparadas ao padrão ouro, principalmente para VO2max>40 mL.kg-1.min-1.

ABSTRACTThe aim was to evaluate the concordance between measurements of VO2max obtained by exercise cardiopulmonary test (gold-standard) vs. that obtained by predictive equations. Men (21-55 years-old) were grouped into Resistance training (RT; n=31), long-distance runners (R; n=28) and non-exercise practitioners (C; n=35). Five equations were tested, one of them made from Brazilian sample. The concordance was evaluated by Bland-Altman, and correlation analysis by Pearson's coefficient (r). The r between gold-standard vs. equations ranged 0.27 to 0.75, with p<0.05 for the most analysis, however, with low concordance. Regarding the equation obtained in Brazilians, the values with lower concordance were, following the order: C, RT and R. In relation to others equations, again with lower concordance, the order was R, RT and C. The worst estimates were to higher VO2max values, mainly for >40 mL.kg-1.min-1. In conclusion, the predictive equations tested generate low concordance when compared to VO2maxgold-standard test, mainly for VO2max>40 mL.kg-1.min-1.

Transição metabólica no teste progressivo de pessoas treinadas com musculação e corrida / Metabolic transition in trained people in progressive test with resistance training and running / Transición metabólica en personas entrenadas para prueba progresiva con musculación y carrera

INTRODUÇÃO: A especificidade das adaptações cardiorrespiratórias e metabólicas do treinamento aeróbio e de força evocam respostas distintas durante o teste cardiopulmonar de exercício (TCPE). Objetivo: Descrever o comportamento cardiorrespiratório durante a transição metabólica (TM) do TCPE, de praticantes de corrida e musculação, comparados a um grupo controle.MÉTODOS: Homens de 21 a 55 anos foram agrupados em: grupo de corredores (GC, n = 30), grupo de musculação (GM, n = 23) e grupo controle (GCON, n = 38). Foram submetidos à avaliação antropométrica e TCPE com análise do limiar anaeróbio ventilatório (LAV) e do ponto de compensação respiratória (PCR). Calculou-se a economia de corrida pela relação entre VO2 e velocidade do teste (ECINCLINA).RESULTADOS: Na fase de transição metabólica, a carga (km/h) foi superior no GC (4,2 ± 1,6) vs. GCON (2,7 ± 1,6) e GM (2,8 ± 1,0); P < 0,05. O GC apresentou maior VO2LAV; VO2PCR e VO2MÁX.(36 ± 8; 46 ± 8; 51 ± 8 vs. 24 ± 6; 35 ± 5; 40 ± 6 e 26 ± 6; 35 ± 6; 40 ± 7 ml.kg-1.min-1; P < 0,05), comparado com GCON e GM, respectivamente, mesmo após a correção alométrica. A FCREP foi menor entre GC e GCON (CE = 52 ± 6; CON = 60 ± 8 bpm;P < 0,05). Na fase de TM, o GC apresentou maior aumento da carga de trabalho e menor alteração do pulso de oxigênio comparado ao GCON e ao GM. O VO2 durante a TM não difere entre os grupos. O GC apresentou menor ECINCLINA nos instantes finais do teste, comparado a GCON e GM.CONCLUSÃO: O GC apresentou maior eficiência metabólica nas transições progressivas de intensidade de esforço em relação a GCON e GM e o GM não exibe capacidade de transição aprimorada no TCPE, até mesmo quando comparados a indivíduos sedentários.

INTRODUCTION: The specificity of cardiorespiratory and metabolic adaptations of aerobic and strength training evoke different responses during cardiopulmonary exercise testing (CPET). Objective: To describe the cardiorespiratory behavior during metabolic transition (MT) of CPET, runners and bodybuilders compared to a control group. METHODS: Men aged 21-55 years were grouped as follows: runners group (RG, n=30), strength group (SG, n=23) and control group (CG, n=38). The subjects underwent anthropometric and CPET assessment with analysis of ventilatory anaerobic threshold (VAT) and the respiratory compensation point (RCP). We calculated the running economy by the relationship between VO2 and test speed (ECINCLINA). RESULTS: In metabolic transition phase, the running speed (km/h) was higher in the RG group (4.2±1.6) vs. CG (2.7±1.6) and SG (2.8±1.0); P<0.05. The RG had higher VO2LAV, VO2PCR, and VO2MAX (36±8; 46±8, 51±8 vs. 24±6, 35±5, 40 ± 6, and 26±6, 35±6, 40± 7ml.kg-1.min-1; P<0.05) compared to group CG and SG, respectively, even after allometric correction. The resting heart rate was lower among RG and CG (R=52±6; C=60±8 bpm, P<0.05). In the MT phase the RG had a greater increase in workload and less change in oxygen pulse compared to CG and SG. The VO2 during MT did not differ between groups. The RG showed lower ECINCLINA in the closing stages of the test compared to CG and SG. CONCLUSION: The RG showed higher metabolic efficiency in progressive transitions of effort intensity in relation to CG and SG and the SG does not display enhanced transition capacity in CPET, even when compared to sedentary individuals.

INTRODUCCIÓN: La especificidad de las adaptaciones cardiorrespiratorias y metabólicas del entrenamiento aeróbico y de fuerza evoca diferentes respuestas durante la prueba de esfuerzo cardiopulmonar (PECP). Objetivo: Describir el comportamiento cardiorrespiratorio durante la transición metabólica (TM) de la PECP, de corredores y culturistas, en comparación con un grupo control.MÉTODOS: Hombres entre 21 y 55 años fueron agrupados de la siguiente manera: grupo corredores (GC; n = 30), grupo culturistas (GCU; n = 23) y grupo control (GCON; n = 38). Los participantes se sometieron a evaluación antropométrica y PECP, con el análisis de umbral anaeróbico ventilatorio (UAV) y el punto de compensación respiratoria (PCR). Se calculó la economía de carrera mediante la relación entre VO2 y velocidad de la prueba (ECINCLINA).RESULTADOS: En la transición metabólica, la carga (km/h) fue mayor en el GC (4,2 ± 1,6) vs. GCON (2,7 ± 1,6) y GCU (2,8 ± 1,0); P < 0,05. El GC presentó mayor VO2UAV; VO2RCPy VO2MÁX.(36 ± 8; 46 ± 8; 51 ± 8 vs. 24 ± 6; 35 ± 5; 40 ± 6 y 26 ± 6; 35 ± 6; 40 ± 7 ml.kg-1.min-1; P < 0,05), en comparación con GCON y GCU, respectivamente, incluso después de la corrección alométrica. La FCREPfue menor entre GD y GCON (GC = 52 ± 6; GCON = 60 ± 8 bpm; P < 0,05). La fase de TM en el GC presentó mayor aumento de carga de trabajo y menos cambios en el pulso de oxígeno en comparación con GCON y GCU. El VO2 durante la TM no difirió entre los grupos. El GC mostró menor ECINCLINA en los momentos finales de la prueba en comparación con GCON y GCU.CONCLUSIÓN: El GC mostró una mayor eficiencia metabólica en las transiciones progresivas de esfuerzo en comparación con GCON y GCU, y GCU no muestra una mayor capacidad de transición en el PECP, incluso en comparación con los individuos sedentarios.

Efeito do treinamento sobre a eficiência ventilatória de indivíduos saudáveis / Effect of training on ventilatory efficiency in healthy subjects / Efecto del entrenamiento sobre la eficiencia ventilatoria de individuos saludables

Introdução: Diversos índices de eficiência ventilatória (EV) têm fornecido uma medida extra para avaliação do condicionamento cardiorrespiratório em adição ao consumo de oxigênio (VO2) no pico do exercício e no nível do limiar ventilatório (VO2LV). Em indivíduos com insuficiência cardíaca já foi demonstrado que há aumento da EV após treinamento. No entanto, a sensibilidade dessa medida para avaliar o efeito do treinamento em indivíduos saudáveis foi pouco estudada. Objetivo: Testar a hipótese de que um programa de treinamento delineado para melhorar a condição aeróbia, também exerça alterações na eficiência ventilatória em indivíduos saudáveis. Métodos: 48 homens, aparentemente saudáveis e ativos (24±5 anos), foram submetidos a um teste cardiopulmonar de exercício (TCPE), antes e após 13 semanas de treinamento aeróbio, realizado três vezes por semana, durante 30 minutos com a intensidade inicial de 60-65% da FCmáx, gradualmente aumentada até o fim do programa para 85-90% da FCmax. Os parâmetros avaliados incluíram: VO2pico, VO2 no LV e EV determinada através do cálculo do slope da relação entre a ventilação e a produção de dióxido de carbono, por meio de regressão linear. Resultados: Houve um aumento de 12,5% no VO2LV (30,4±4,5 vs. 34,2±4,9 ml.kg-1.min-1, p<0,05) e de 10,9% no VO2pico (53,2±8,3 vs. 59±9,9 ml.kg-1.min-1, p<0,05), acompanhado de uma redução de 4,1% no slope VE-VCO2 (25,2±3,3 vs. 24,2±3,7, p<0,05). Conclusão: A EV aumenta após o treinamento em homens saudáveis sugerindo que o slope da relação VE-VCO2 pode ser utilizado de forma adicional na monitoração ...

Introduction: Several indices of ventilatory efficiency (VE) have provided an extra measure to assess cardiorespiratory fitness in addition to oxygen uptake (VO2) at peak exercise and at the level of ventilatory threshold (VO2VT). In patients with heart failure has been demonstrated that there is increase of ventilatory efficiency after training. However, the sensitivity of this measure to assess the effect of training in health subjects has been little studied. Objective: To test the hypothesis that a training program designed to improve aerobic fitness also changes the ventilatory efficiency in healthy subjects. Methods: 48 men seemingly healthy and active (24±5 years) underwent a cardiopulmonary exercise test (CPET) before and after 13 weeks of aerobic training, performed three times a week for 30 minutes with the initial intensity 60-65% of maximum heart rate (HRmax) gradually increased until the end of program for 85-90% of HRmax. The parameters evaluated included: VO2peak, VO2VT and ventilatory efficiency that was determined by calculating the slope of the relationship between ventilation and production of carbon dioxide by linear regression. Results: There was a 12.5% increase in VO2VT (30.4 ± 4.5 vs. 34.2 ± 4.9 ml.kg-1.min-1, p <0.05) and 10.9% in VO2peak (53.2 ± 8.3 vs. 59 ± 9.9, ml.kg-1.min-1 p<0.05), accompanied by a 4.1% reduction in VE-VCO2 slope (25.2 ± 3.3 vs. 24.2 ± 3.7, p<0.05). Conclusion: Ventilatory efficiency increases after training in healthy men suggesting that the slope of the relationship VE-VCO2 can be used in addition to the monitoring of the effects of training, complementing the interpretation of cardiorespiratory integration of CEPT. .

Introducción: Diversos índices de eficiencia ventilatoria (EV) han suministrado una medida extra para evaluación del condicionamiento cardiorrespiratorio en adición al consumo de oxígeno (VO2) en el pico del ejercicio y en el nivel del umbral ventilatorio (VO2LV). En individuos con insuficiencia cardíaca ya fue demostrado que hay aumento de la EV después del entrenamiento. Sin embargo, la sensibilidad de esa medida para evaluar el efecto del entrenamiento en individuos saludables fue poco estudiada. Objetivo: Probar la hipótesis de que un programa de entrenamiento delineado para mejorar la condición aeróbica, que también ejerza alteraciones en la eficiencia ventilatoria en individuos saludables. Métodos: 48 hombres, aparentemente saludables y activos (24±5 años), fueron sometidos a un test cardiopulmonar de ejercicio (TCPE), antes y después de 13 semanas de entrenamiento aeróbico, realizado tres veces por semana, durante 30 minutos con la intensidad inicial de 60-65% de la FCmax, gradualmente aumentada hasta el fin del programa para 85-90% de la FCmax. Los parámetros evaluados incluyeron: VO2pico, VO2 en el LV y EV determinada a través del cálculo del slope de la relación entre la ventilación y la producción de dióxido de carbono, por medio de regresión lineal. Resultados: Hubo un aumento de 12,5% en el VO2LV (30,4±4,5 vs. 34,2±4,9 ml.kg-1.min-1, p<0,05) y de 10,9% en el VO2pico (53,2±8,3 vs. 59±9,9 ml.kg-1.min-1, p<0,05), acompañado de una reducción de 4,1% en el slope VE-VCO2 (25,2±3,3 vs. 24,2±3,7, p<0,05). Conclusión: La EV aumenta después del entrenamiento en hombres saludables sugiriendo que el slope de la relación VE-VCO2 puede ser utilizado de forma adicional en el monitoreo de los efectos del entrenamiento, complementando la i...