The importance of first and second ventilatory thresholds to define aerobic exercise intensity in cardiac patients and in healthy subjects: what is essential can be visible to the eyes

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
F Anselmi ◽  
L Cavigli ◽  
A Pagliaro ◽  
S Valente ◽  
F Valentini ◽  
...  
Keyword(s):  
Exercise Intensity ◽  
Healthy Subjects ◽  
Ventilatory Threshold ◽  
Cardiopulmonary Exercise Testing ◽  
Cardiac Patients ◽  
Funding Sources ◽  
Peak Vo2 ◽  
Definition Of ◽  
Very High ◽  
Sedentary Subjects

Abstract Funding Acknowledgements Type of funding sources: None. Background. Although structured exercise training is strongly recommended in cardiac patients, uncertainties exist about the methods for determining exercise intensity (EI) and their correspondence with effective EI obtained by ventilatory thresholds. We aimed to determine the first (VT1) and second ventilatory threshold (VT2) in cardiac patients, sedentary subjects and athletes comparing VT1 and VT2 with EI defined by recommendations. Methods. We prospectively enrolled 350 subjects (mean age: 50.7 ± 12.9 years; 167 cardiac patients, 150 healthy sedentary subjects, 33 competitive endurance athletes). Each subject underwent ECG, echocardiography, and cardiopulmonary exercise testing. The percentages of peak VO2, peak heart rate (HR), and HR reserve were obtained at VT1 and VT2, and compared with EI definition proposed by the recommendations. Results. VO2 at VT1 corresponded to high rather than moderate EI in 67.1% and in 79.6% of cardiac patients, applying the definition of moderate exercise by the previous recommendations and the 2020 guidelines, respectively. Most of cardiac patients had VO2 values at VT2 corresponding to very-high rather than high EI (59.9% and 50.3%, by previous recommendations and 2020 guidelines, respectively). A better correspondence between ventilatory-thresholds and recommended EI domains was observed in healthy subjects and in athletes (90% and 93.9%, respectively). Conclusions. EI definition based on percentages of peak HR and peak VO2 may misclassify the effective EI and the discrepancy between the individually determined and the recommended EI is particularly relevant in cardiac patients. A ventilatory threshold-based rather than a range-based approach is advisable in order to define an appropriate level of EI. Abstract Figure.

Abstract 14453: Ventilatory Inefficiency Associated With Stage a Heart Failure

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Elizabeth L Potter ◽  
Mary N Woessner ◽  
Christopher Neil ◽  
Thomas H Marwick ◽  
Erin Howden
Keyword(s):  
Risk Factors ◽  
Heart Failure ◽  
Ventilatory Threshold ◽  
Global Longitudinal Strain ◽  
Prognostic Significance ◽  
Cardiopulmonary Exercise Testing ◽  
Left Ventricular ◽  
Prognostic Information ◽  
Risk Profiling ◽  
Sedentary Subjects

Introduction: Peak oxygen utilisation (VO 2 ) and ventilatory efficiency (VE/VCO 2 slope) provide strong prognostic information in symptomatic heart failure (HF). Transition from subclinical to symptomatic HF is poorly understood. Cardiopulmonary exercise testing (CPET) in subclinical HF may advance risk profiling. Hypothesis: HF risk factors are associated with metabolic and ventilatory abnormalities that may serve as risk markers. Methods: Sedentary subjects (n=81; 67 (66-72) years; 65% female; BMI 29.9[26.6-33.9] kg/m 2 ) with ≥1 HF risk factors (Stage A HF, SAHF) without pulmonary disease and healthy sedentary subjects (controls, n=21; 70 (67-73) years; 52% female; BMI 25.1 [24-25.9] kg/m 2 ) underwent treadmill CPET to determine peak VO 2 , ventilatory threshold (VT, V-slope method) and VE/VCO 2 slope (linear regression). Global longitudinal strain≤16%, diastolic dysfunction or left ventricular hypertrophy defined subclinical left ventricular dysfunction (LVD). Results: LVD was present in 41 (51%) with SAHF. CPET parameters did not differ by presence of LVD. There were no differences in peak RER or VT (% peak VO2) between controls and SAHF. VO 2 peak was higher in controls vs. SAHF (22.1±4.6 vs. 19.9±4.6ml/kg/min, p=0.047). VE/VCO 2 slope was markedly steeper in SAHF vs. controls (40.2±6.2 vs. 29.3±6.1, p<0.001) (Figure). VE/VCO 2 slope was >34 (prognostic in symptomatic HF) in 83% vs. 19% for SAHF vs. controls (p<0.001). BMI was the only independent predictor (β 0.45 (0.19-0.72, p=0.001) (r 2 0.16) of VE/VCO 2 slope (SBP and heart rate reserve were not). BMI was not associated with increment in respiratory rate or tidal volume (β0.18(-0.07-0.42) and β3.9 (-10.8-18.7)). Conclusions: Cardiorespiratory exercise parameters do not differ in SAHF by presence of LVD. Ventilatory inefficiency is pronounced in SAHF compared with healthy controls suggesting it may be a risk marker, but prognostic significance is unknown.

Assessing post-exercise respiratory gas kinetics in clinical sample - a pilot study

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
A Patti ◽  
Y Blumberg ◽  
KJ Moneghetti ◽  
D Neunhaeuserer ◽  
F Haddad ◽  
...  
Keyword(s):  
Heart Failure ◽  
Healthy Subjects ◽  
Cardiopulmonary Exercise Testing ◽  
University Hospital ◽  
Exercise Intolerance ◽  
Early Recovery ◽  
Post Exercise ◽  
Peak Vo2 ◽  
Significant Difference ◽  
Respiratory Gases

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiopulmonary exercise testing (CPX) is established in the evaluation of patients with cardiac and pulmonary diseases, and its clinical utility seems to be expanding.  Currently the most important diagnostic and prognostic ventilatory metrics of CPX rely on the exercise phase. Nevertheless, a consistent body of evidence suggests that important information can be derived from the recovery phase, especially in the first few minutes after exercise. In this context, patients with heart failure (HF) demonstrate a slower recovery of the oxygen consumption (VO2) compared with healthy individuals. Purpose: To comprehensively investigate the behavior of respiratory gases during recovery from CPX in a diverse cohort of HF patients. Methods: All individuals who performed CPX at the department of cardiology of Stanford University Hospital were eligible for the study. Patients were included in the experimental group if they (i) were recorded for five minutes after the exercise phase of CPX and (ii) had documented heart failure. They were excluded if they had other clinical diagnoses which may be responsible for exercise intolerance or symptoms or were unable to give informed consent. Healthy controls were recruited from the local community and were included if they did not have documented or suspected disease. Respiratory gases were collected on a breath-by-breath basis and analysed after applying a 30 second rolling average filter. Metrics were analyzed as absolute values, percentage change from peak and the half-time of recovery (T ½; i.e. the duration until a metric had returned to ½ of its value at peak). Data was analyzed over time within patients and averages between groups using parametric statistical methods. In accordance with previous studies, the amount of change in a metric after exercise is presented as the "magnitude" of overshoot. Results: 32 patients with HF (11 Female, 47 ± 13 yrs) and 30 healthy subjects (14 Female, 43 ± 12 yrs) were included. A comparison of ventilatory metrics during recovery between HF and controls is depicted in Figure 1. Peak VO2 was 1135 ± 419 mL/min (13.5 ± 3.8 mL/Kg/min) vs 2408 ± 787 mL/min (32.5 ± 9.0 mL/Kg/min); P &lt;0.01. A significant difference between patients with HF and healthy subjects was found in T ½ of VO2 (111.3 ± 51.0s vs 58.0 ± 13.2s, p &lt; 0.01) and VCO2 (132.0 ± 38.8s vs 74.3 ± 21.1s, p &lt; 0.01). The magnitude of the overshoot was also found to be significantly reduced in patients with HF for VE/VO2 (41.9 ± 29.1% vs 62.1 ± 17.7%, P &lt; 0.01), RQ (25.0 ± 13.6% vs 38.7 ± 15.1%, p &lt; 0.01) and PETO2 (7.2 ± 3.3% vs 10.1 ± 4.6%, p &lt; 0.01). Finally, the magnitude of the RQ overshoot showed a moderate correlation with peak VO2 (ϱ=0.58, p &lt; 0.01). Conclusions: We observed that ventilatory kinetics measured in early recovery after CPX differ significantly between healthy subjects and patients with HF. The assessment of post exercise respiratory gases in a clinical setting may add to the prognostic and diagnostic value of CPX in heart failure. Abstract Figure.

scholarly journals Oxygen consumption and heart rate obtained in a ramp protocol are equivalent during exercise session of rectangular loading at ventilatory thresholds for athletes

2019 ◽  
Vol 21 ◽  
Author(s):  
Victor Hugo Gasparini Neto ◽  
Paulo Azevedo ◽  
Luciana Carletti ◽  
Anselmo José Perez
Keyword(s):  
Heart Rate ◽  
Exercise Prescription ◽  
Ventilatory Threshold ◽  
Cardiopulmonary Exercise Testing ◽  
Exercise Session ◽  
Cardiopulmonary Exercise ◽  
Adequate Stimulus ◽  
Continuous Running ◽  
Sedentary Subjects ◽  
Good Agreement

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.

scholarly journals The importance of ventilatory thresholds to define aerobic exercise intensity in cardiac patients and healthy subjects

2021 ◽  
Author(s):  
Francesca Anselmi ◽  
Luna Cavigli ◽  
Antonio Pagliaro ◽  
Serafina Valente ◽  
Francesca Valentini ◽  
...  
Keyword(s):  
Aerobic Exercise ◽  
Exercise Intensity ◽  
Healthy Subjects ◽  
Cardiac Patients

scholarly journals Operationalizing the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Cancer Prevention Recommendations: A Standardized Scoring System (P13-034-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Marissa Shams-White ◽  
Alice Bender ◽  
Nigel Brockton ◽  
Susannah Brown ◽  
Lisa Kahle ◽  
...  
Keyword(s):  
Cancer Research ◽  
Cancer Prevention ◽  
Past Research ◽  
Healthy Weight ◽  
National Guidelines ◽  
Physically Active ◽  
Supplement Use ◽  
Funding Sources ◽  
Sweetened Beverages ◽  
Definition Of

Abstract Objectives To develop a standardized AICR/WCRF Score that measures adherence to the 2018 WCRF/AICR Cancer Prevention Recommendations and provide guidance for its application in research. Methods Each of the updated 2018 WCRF/AICR Cancer Prevention Recommendations and the associated goals and statements of advice were examined to inform the definition of a new Score. For each of the weight, physical activity, diet, and breastfeeding-specific recommendations, components and subcomponents were created. Standards for scoring each component were established based on quantitative guidance specified in the recommendations; however, if no specificity was provided, other guidelines (e.g., national guidelines), past research that operationalized 2007 WCRF/AICR recommendations, and expert panel advice were evaluated. Results The proposed AICR/WCRF Score includes eight of the ten WCRF/AICR 2018 recommendations: 1) Be a healthy weight, 2) Be physically active, 3) Eat a diet rich in whole grains, vegetables, fruits, and beans, 4) Limit consumption of fast foods and other processed foods high in fat, starches, or sugars, 5) Limit consumption of red and processed meats, 6) Limit consumption of sugar-sweetened beverages, 7) Limit alcohol consumption, and, optionally, 8) For mothers: breastfeed your baby, if you can. Each of the components are worth one point: 1, 0.5, and 0 points for fully, partially, and not meeting the recommendations, respectively (total Score: 0–7 or 8 points). Two recommendations were not included in the Score due to uncertain intent of supplement use (Do not use supplements for cancer prevention) and the redundancy of the dependent components in the final recommendation (After a cancer diagnosis: follow our Recommendations, if you can). Additional guidance will stress the importance of taking into account other risk factors, such as smoking, in relevant models using the new Score. Conclusions The AICR/WCRF Score is a practical tool operationalizing the 2018 recommendations. Future studies are needed to further examine how adherence to the Score relates to cancer risk and mortality in various populations. Funding Sources None.

scholarly journals Exercise Intensity during Olympic-Distance Triathlon in Well-Trained Age-Group Athletes: An Observational Study

Sports ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 18
Author(s):  
Atsushi Aoyagi ◽  
Keisuke Ishikura ◽  
Yoshiharu Nabekura
Keyword(s):  
Heart Rate ◽  
Observational Study ◽  
Exercise Intensity ◽  
Time Range ◽  
Age Group ◽  
Slow Group ◽  
H 41 ◽  
The Mean ◽  
Aerobic And Anaerobic ◽  
Very High

The aim of this study was to examine the exercise intensity during the swimming, cycling, and running legs of nondraft legal, Olympic-distance triathlons in well-trained, age-group triathletes. Seventeen male triathletes completed incremental swimming, cycling, and running tests to exhaustion. Heart rate (HR) and workload corresponding to aerobic and anaerobic thresholds, maximal workloads, and maximal HR (HRmax) in each exercise mode were analyzed. HR and workload were monitored throughout the race. The intensity distributions in three HR zones for each discipline and five workload zones in cycling and running were quantified. The subjects were then assigned to a fast or slow group based on the total race time (range, 2 h 07 min–2 h 41 min). The mean percentages of HRmax in the swimming, cycling, and running legs were 89.8% ± 3.7%, 91.1% ± 4.4%, and 90.7% ± 5.1%, respectively, for all participants. The mean percentage of HRmax and intensity distributions during the swimming and cycling legs were similar between groups. In the running leg, the faster group spent relatively more time above HR at anaerobic threshold (AnT) and between workload at AnT and maximal workload. In conclusion, well-trained male triathletes performed at very high intensity throughout a nondraft legal, Olympic-distance triathlon race, and sustaining higher intensity during running might play a role in the success of these athletes.

Cardiopulmonary Exercise Testing in Combined Pulmonary Fibrosis and Emphysema

Respiration ◽  
2021 ◽  
pp. 369-377
Author(s):  
Michael Westhoff ◽  
Patric Litterst ◽  
Ralf Ewert
Keyword(s):  
Body Weight ◽  
Pulmonary Fibrosis ◽  
Sensitivity And Specificity ◽  
Exercise Testing ◽  
Cardiopulmonary Exercise Testing ◽  
Arterial Oxygen ◽  
Peak Exercise ◽  
Cutoff Value ◽  
Cardiopulmonary Exercise ◽  
Peak Vo2

Background: Combined pulmonary fibrosis and emphysema (CPFE) is a distinct entity among fibrosing lung diseases with a high risk for lung cancer and pulmonary hypertension (PH). Notably, concomitant PH was identified as a negative prognostic indicator that could help with early diagnosis to provide important information regarding prognosis. Objectives: The current study aimed to determine whether cardiopulmonary exercise testing (CPET) can be helpful in differentiating patients having CPFE with and without PH. Methods: Patients diagnosed with CPFE in 2 German cities (Hemer and Greifswald) over a period of 10 years were included herein. CPET parameters, such as peak oxygen uptake (peak VO2), functional dead space ventilation (VDf/VT), alveolar-arterial oxygen difference (AaDO2), arterial-end-tidal CO2 difference [P(a-ET)CO2] at peak exercise, and the minute ventilation-carbon dioxide production relationship (VE/VCO2 slope), were compared between patients with and without PH. Results: A total of 41 patients with CPET (22 with PH, 19 without PH) were analyzed. Right heart catheterization was performed in 15 of 41 patients without clinically relevant complications. Significant differences in peak VO2 (861 ± 190 vs. 1,397 ± 439 mL), VO2/kg body weight/min (10.8 ± 2.6 vs. 17.4 ± 5.2 mL), peak AaDO2 (72.3 ± 7.3 vs. 46.3 ± 14.2 mm Hg), VE/VCO2 slope (70.1 ± 31.5 vs. 39.6 ± 9.6), and peak P(a-ET)tCO2 (13.9 ± 3.5 vs. 8.1 ± 3.6 mm Hg) were observed between patients with and without PH (p < 0.001). Patients with PH had significantly higher VDf/VT at rest, VT1, and at peak exercise (65.6 ± 16.8% vs. 47.2 ± 11.6%; p < 0.001) than those without PH. A cutoff value of 44 for VE/VCO2 slope had a sensitivity and specificity of 94.7 and 72.7%, while a cutoff value of 11 mm Hg for P(a-ET)CO2 in combination with peak AaDO2 >60 mm Hg had a specificity and sensitivity of 95.5 and 84.2%, respectively. Combining peak AaDO2 >60 mm Hg with peak VO2/body weight/min <16.5 mL/kg/min provided a sensitivity and specificity of 100 and 95.5%, respectively. Conclusion: This study provided initial data on CPET among patients having CPFE with and without PH. CPET can help noninvasively detect PH and identify patients at risk. AaDO2 at peak exercise, VE/VCO2 slope, peak P(a-ET)CO2, and peak VO2 were parameters that had high sensitivity and, when combined, high specificity.

The talk test"s responsiveness to an 8-week exercise-training program in cardiovascular disease patients

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
EM Martins ◽  
LS Silveira ◽  
GS Ribeiro ◽  
AM Vieira ◽  
ABAO Roque ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
Exercise Training ◽  
Training Program ◽  
Ventilatory Threshold ◽  
Rehabilitation Program ◽  
Wilcoxon Test ◽  
Heart Rate Variability Analysis ◽  
Funding Sources ◽  
Exercise Training Program ◽  
6Mwt Distance

Abstract Funding Acknowledgements Type of funding sources: None. Background Talk test (TT) is an alternative and accessible tool for prescribing and monitoring aerobic training intensity. Although the TT is reliable and valid for cardiorespiratory assessment, its responsiveness to exercise training remains unexplored. Purpose To evaluate the responsiveness of TT in cardiovascular disease (CVD) patients who underwent an exercise training program. Methods Twenty-one CVD patients (61.7 ± 8.4 years) performed an exercise-training program on phase II of cardiac rehabilitation (45-min 3-times a week). The six-minute walk test (6MWT) and TT were done to assess functional capacity at baseline and after 8 weeks. In the individualized TT the treadmill’s speed and/or grade were increased every 2-min, with speed changes based on a reference equation for the 6MWT distance (6MWD). The subjects were asked to read a 38 words standard paragraph at the last 30s of each stage and to answer if they could talk comfortably. Answer options were i) YES (TT+), ii) UNCERTAIN (TT±), or iii) NO (TT-). The first ventilatory threshold (VT1) was identified by two reviewers using the heart rate variability analysis. A paired t-test was applied to analyze the TT duration and 6MWD. The VT1 and TT workload were analyzed by the Wilcoxon test. Spearman correlation was adopted to compare the TT± and VT1 stages. Results Improvement in the VT1 (2.9 ± 1.2 vs 4.4 ± 1.4 min; p &lt; 0.001), duration (12.1 ± 4.4 vs 14.9 ± 5.2 min; p &lt; 0.001), workload at TT- (67.8 ± 48.4 vs 104.5 ± 65.9 w; p &lt; 0.001), and in the 6MWD (471.5 ± 100.3 vs 533.7 ± 92.9 m; p &lt; 0.001) were observed. There was strong correlation between TT± and VT1 in pre (r = 0.613; p &lt; 0.05) and post-rehabilitation (r = 0.678; p &lt; 0.05). Conclusion Talk test performed on a treadmill showed responsiveness after eight weeks of exercise training, being sensitive to the physiological changes provided by the rehabilitation program in CVD patients.

Anion packing density: a universal quantity for both dense and porous crystalline inorganic phases

2002 ◽  
Vol 58 (3) ◽  
pp. 457-462 ◽  
Author(s):  
F. Liebau ◽  
H. Küppers
Keyword(s):  
High Pressure ◽  
Packing Density ◽  
Three Dimensional ◽  
Ionic Radii ◽  
Generalized Framework ◽  
Molal Volumes ◽  
Definition Of ◽  
Anion Packing ◽  
Very High ◽  
Framework Density

To compare densities of inorganic high-pressure phases their molal volumes or specific gravities are usually employed, whereas for zeolites and other microporous materials the so-called framework density, FD, is applied. The definition of FD, which refers only to phases with three-dimensional tetrahedron frameworks, is extended to a `generalized framework density' d f, which is independent of the dimensionality of the framework and the coordination number(s) of the framework cations. In this paper the anion packing density, d ap, is introduced as a new quantity which is not only applicable to any inorganic phase but, in contrast to FD and d f, also allows quantitative comparisons to be made for crystalline inorganic phases of any kind. The anion packing density can readily be calculated if the volume and content of the unit cell and the radii of the anions of a phase are known. From d ap values calculated for high-pressure silica polymorphs studied under very high pressure, it is concluded that Shannon–Prewitt effective ionic radii do not sufficiently take into account the compressibility of the anions.

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