scholarly journals Feeding Tolerance, Glucose Availability, and Whole-Body Total Carbohydrate and Fat Oxidation in Male Endurance and Ultra-Endurance Runners in Response to Prolonged Exercise, Consuming a Habitual Mixed Macronutrient Diet and Carbohydrate Feeding During Exercise

2022 ◽  
Vol 12 ◽  
Author(s):  
Christopher E. Rauch ◽  
Alan J. McCubbin ◽  
Stephanie K. Gaskell ◽  
Ricardo J. S. Costa
Keyword(s):  
Steady State ◽  
Exercise Test ◽  
Fat Oxidation ◽  
Incremental Exercise ◽  
Whole Body ◽  
Oxidation Rates ◽  
Incremental Exercise Test ◽  
Carbohydrate Feeding ◽  
Endurance Runners ◽  
Ultra Endurance

Using metadata from previously published research, this investigation sought to explore: (1) whole-body total carbohydrate and fat oxidation rates of endurance (e.g., half and full marathon) and ultra-endurance runners during an incremental exercise test to volitional exhaustion and steady-state exercise while consuming a mixed macronutrient diet and consuming carbohydrate during steady-state running and (2) feeding tolerance and glucose availability while consuming different carbohydrate regimes during steady-state running. Competitively trained male endurance and ultra-endurance runners (n = 28) consuming a balanced macronutrient diet (57 ± 6% carbohydrate, 21 ± 16% protein, and 22 ± 9% fat) performed an incremental exercise test to exhaustion and one of three 3 h steady-state running protocols involving a carbohydrate feeding regime (76–90 g/h). Indirect calorimetry was used to determine maximum fat oxidation (MFO) in the incremental exercise and carbohydrate and fat oxidation rates during steady-state running. Gastrointestinal symptoms (GIS), breath hydrogen (H2), and blood glucose responses were measured throughout the steady-state running protocols. Despite high variability between participants, high rates of MFO [mean (range): 0.66 (0.22–1.89) g/min], Fatmax [63 (40–94) % V̇O2max], and Fatmin [94 (77–100) % V̇O2max] were observed in the majority of participants in response to the incremental exercise test to volitional exhaustion. Whole-body total fat oxidation rate was 0.8 ± 0.3 g/min at the end of steady-state exercise, with 43% of participants presenting rates of ≥1.0 g/min, despite the state of hyperglycemia above resting homeostatic range [mean (95%CI): 6.9 (6.7–7.2) mmol/L]. In response to the carbohydrate feeding interventions of 90 g/h 2:1 glucose–fructose formulation, 38% of participants showed breath H2 responses indicative of carbohydrate malabsorption. Greater gastrointestinal symptom severity and feeding intolerance was observed with higher carbohydrate intakes (90 vs. 76 g/h) during steady-state exercise and was greatest when high exercise intensity was performed (i.e., performance test). Endurance and ultra-endurance runners can attain relatively high rates of whole-body fat oxidation during exercise in a post-prandial state and with carbohydrate provisions during exercise, despite consuming a mixed macronutrient diet. Higher carbohydrate intake during exercise may lead to greater gastrointestinal symptom severity and feeding intolerance.

Reduced Fat Oxidation During Exercise in Post-Menopausal Overweight-Obese Women with Higher Lipid Accumulation Product Index

2018 ◽  
Vol 128 (08) ◽  
pp. 556-562 ◽  
Author(s):  
Elana Stein ◽  
Igor Martins Silva ◽  
Gilson P. Dorneles ◽  
Fabio Santos Lira ◽  
Pedro Romão ◽  
...  
Keyword(s):  
Exercise Test ◽  
Lipid Accumulation ◽  
Fat Oxidation ◽  
Incremental Exercise ◽  
Metabolic Phenotype ◽  
Whole Body ◽  
Obese Women ◽  
Incremental Exercise Test ◽  
Significant Difference ◽  
Post Menopausal

Abstract Background and Aims The main aim of this study was to analyze how the lipid accumulation affects the whole-body fat oxidation over a range of intensities during a submaximal incremental exercise test in post-menopausal overweight-obese women. Patients and Methods The maximal fat oxidation (MFO), the intensity where the MFO occurs (FatMax), fat oxidation were measured over a range of intensities during a submaximal incremental exercise test through indirect calorimetry in 60 postmenopausal overweight-obese women (aged>49 years; body mass index 28.0 to 39.0 kg/m²). The metabolic profile of participants was evaluated and the LAP index was calculated (waist-58×triglycerides [mmol/L]). A cutoff point of 34.5 was adopted and participant were designed as low LAP index (n=30) or high LAP index (n=30). Results During submaximal exercise postmenopausal overweight-obese women with low LAP index showed a higher fat oxidation at 50% (0.53±0.05 vs. 0.45±0.12 g/min; p=0.01), 60% (0.40±0.06 vs. 0.31±0.16 g/min; p=0.02) and 70% (0.34±0.08 vs. 0.25±0.15 g/min; p=0.03) of VO2Peak than those with high LAP index. No significant difference was observed in carbohydrate oxidation between groups (p>0.05) during exercise. Moreover, a significant difference in absolute MFO (p=0.018), MFO relative to free fat mass (p=0.043) and FatMax (p=0.002) was identified. Conclusion Postmenopausal overweight-obese women who showed unhealthy metabolic phenotype evaluated through LAP index presented low fat oxidation during a submaximal incremental exercise.

Maximal oxygen uptake, ventilatory threshold and fat oxidation after an incremental exercise test in triathletes

2017 ◽  
Vol 176 (12) ◽  
Author(s):  
Hanapi M. Johari ◽  
Brinnell A. Caszo ◽  
Victor F. Knight ◽  
Steven A. Lumley ◽  
Aminuddin K. Abdul Hamid ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Exercise Test ◽  
Maximal Oxygen Uptake ◽  
Ventilatory Threshold ◽  
Fat Oxidation ◽  
Incremental Exercise ◽  
Incremental Exercise Test

Evaluation of a graded exercise test to determine peak fat oxidation in individuals with low cardiorespiratory fitness

2018 ◽  
Vol 43 (12) ◽  
pp. 1288-1297 ◽  
Author(s):  
Oliver J. Chrzanowski-Smith ◽  
Robert M. Edinburgh ◽  
James A. Betts ◽  
Keith A. Stokes ◽  
Javier T. Gonzalez
Keyword(s):  
Steady State ◽  
Gas Exchange ◽  
Test Validity ◽  
Endurance Performance ◽  
Fat Oxidation ◽  
Peak Oxygen Consumption ◽  
Intraindividual Variation ◽  
Exercise Tests ◽  
Oxidation Rates ◽  
Ultra Endurance

The maximal capacity to utilise fat (peak fat oxidation, PFO) may have implications for health and ultra-endurance performance and is commonly determined by incremental exercise tests employing 3-min stages. However, 3-min stages may be insufficient to attain steady-state gas kinetics, compromising test validity. We assessed whether 4-min stages produce steady-state gas exchange and reliable PFO estimates in adults with peak oxygen consumption < 40 mL·kg−1·min−1. Fifteen participants (9 females) completed a graded test to determine PFO and the intensity at which this occurred (FATMAX). Three short continuous exercise sessions (SCE) were then completed in a randomised order, involving completion of the graded test to the stage (i) preceding, (ii) equal to (SCEequal), or (iii) after the stage at which PFO was previously attained, whereupon participants then continued to cycle for 10 min at that respective intensity. Expired gases were sampled at minutes 3–4, 5–6, 7–8, and 9–10. Individual data showed steady-state gas exchange was achieved within 4 min during SCEequal. Mean fat oxidation rates were not different across time within SCEequal nor compared with the graded test at FATMAX (both p > 0.05). However, the graded test displayed poor surrogate validity (SCEequal, minutes 3–4 vs. 5–6, 7–8, and 9–10) and day-to-day reliability (minutes 3–4, SCEequal vs. graded test) to determine PFO, as evident by correlations (range: 0.47–0.83) and typical errors and 95% limits of agreement (ranges: 0.03–0.05 and ±0.09–0.15 g·min−1, respectively). In conclusion, intraindividual variation in PFO is substantial despite 4-min stages establishing steady-state gas exchange in individuals with low fitness. Individual assessment of PFO may require multiple assessments.

An equation to predict the maximal lactate steady state from ramp-incremental exercise test data in cycling

2018 ◽  
Vol 21 (12) ◽  
pp. 1274-1280 ◽  
Author(s):  
Danilo Iannetta ◽  
Federico Y. Fontana ◽  
Felipe Mattioni Maturana ◽  
Erin Calaine Inglis ◽  
Silvia Pogliaghi ◽  
...  
Keyword(s):  
Steady State ◽  
Test Data ◽  
Exercise Test ◽  
Incremental Exercise ◽  
Maximal Lactate Steady State ◽  
Incremental Exercise Test

scholarly journals Comparison of the Ramp and Step Incremental Exercise Test Protocols in Assessing the Maximal Fat Oxidation Rate in Youth Cyclists

2021 ◽  
Vol 80 (1) ◽  
pp. 163-172
Author(s):  
Kamil Michalik ◽  
Natalia Danek ◽  
Marek Zatoń
Keyword(s):  
Oxygen Uptake ◽  
Exercise Test ◽  
Oxidation Rate ◽  
Fat Oxidation ◽  
Incremental Exercise ◽  
Step Test ◽  
Exercise Tests ◽  
Incremental Exercise Test ◽  
Ramp Test ◽  
Maximal Fat Oxidation

Abstract The incremental exercise test is the most common method in assessing the maximal fat oxidation (MFO) rate. The main aim of the study was to determine whether the progressive linear RAMP test can be used to assess the maximal fat oxidation rate along with the intensities that trigger its maximal (FATmax) and its minimal (FATmin) values. Our study comprised 57 young road cyclists who were tested in random order. Each of them was submitted to two incremental exercise tests on an electro-magnetically braked cycle-ergometer - STEP (50 W·3 min-1) and RAMP (~0.278 W·s-1) at a 7-day interval. A stoichiometric equation was used to calculate the fat oxidation rate, while the metabolic thresholds were defined by analyzing ventilation gases. The Student’s T-test, Bland-Altman plots and Pearson’s linear correlations were resorted to in the process of statistical analysis. No statistically significant MFO variances occurred between the tests (p = 0.12) and its rate amounted to 0.57 ± 0.15 g·min-1 and 0.53 ± 0.17 g·min-1 in the STEP and RAMP, respectively. No statistically significant variances in the absolute and relative (to maximal) values of oxygen uptake and heart rate were discerned at the FATmax and FATmin intensities. The RAMP test displayed very strong oxygen uptake correlations between the aerobic threshold and FATmax (r = 0.93, R2 = 0.87, p < 0.001) as well as the anaerobic threshold and FATmin (r = 0.88, R2 = 0.78, p < 0.001). Our results corroborate our hypothesis that the incremental RAMP test as well as the STEP test are reliable tools in assessing MFO, FATmax and FATmin intensities.

Changes in physiological, haematological and biochemical parameters in police working dogs during a treadmill incremental exercise test

2020 ◽  
Vol 16 (5) ◽  
pp. 387-394
Author(s):  
J.C. Alves ◽  
A. Santos ◽  
P. Jorge ◽  
M.P. Lafuente
Keyword(s):  
Exercise Test ◽  
Biochemical Parameters ◽  
Complete Blood Count ◽  
Rest Period ◽  
Incremental Exercise ◽  
Total Plasma ◽  
Incremental Exercise Test ◽  
Total Plasma Protein ◽  
Working Dogs ◽  
Stage T1

This study aimed to evaluate the physiological, haematological and biochemical changes during a treadmill incremental exercise test (IET). Animals were submitted to five stages of 6 min each, at 6, 7, 8, 9 and 10 mph, at an inclination of 5%. Blood samples were collected at rest (T0), immediately after exercise (T5) and after a 20 min rest period (T6), to determine complete blood count, urea, creatinine, creatine kinase, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, total plasma protein, albumin, alkaline phosphatase (AP), cholesterol, triglycerides (Trig), Ca2+, Na+, K+ and Cl-. Blood lactate (BL), heart rate (HR), rectal temperature (RT) and glycaemia were measured at rest (T0), after each stage (T1-T5) and after the rest period (T6). Variations were recorded between T0 and T5 in red blood cells, haemoglobin, AP, Na+, K+ (P<0.01), Trig (P<0.05), Ca2+ and Cl- (P<0.02). Differences were observed in BL at T5 (P<0.02) and T6 (P<0.02), RT at T2-T6 (P<0.01), HR at T3-T5 (P<0.01) and glycaemia at T2-T4 (P<0.01) and T5 (P<0.05). This study is a novel description of the shifts of physical fit police working dogs during this IET protocol.

scholarly journals Ventilatory compensation during the incremental exercise test is inversely correlated with air trapping in COPD

F1000Research ◽  
2020 ◽  
Vol 8 ◽  
pp. 1661
Author(s):  
Rottem Kuint ◽  
Neville Berkman ◽  
Samir Nusair
Keyword(s):  
Gas Exchange ◽  
Exercise Testing ◽  
Exercise Test ◽  
Cardiopulmonary Exercise Testing ◽  
Incremental Exercise ◽  
Peak Exercise ◽  
Air Trapping ◽  
Incremental Exercise Test ◽  
Cardiopulmonary Exercise ◽  
Copd Patients

Background: Air trapping and gas exchange abnormalities are major causes of exercise limitation in chronic obstructive pulmonary disease (COPD). During incremental cardiopulmonary exercise testing, actual nadir values of ventilatory equivalents for carbon dioxide (V E/VCO 2) and oxygen (V E/VO 2) may be difficult to identify in COPD patients because of limited ventilatory compensation capacity. Therefore, we aimed in this exploratory study to detect a possible correlation between the magnitude of ventilation augmentation, as manifested by increments in ventilatory equivalents from nadir to peak exercise values and air trapping, detected with static testing.    Methods: In this observational study, we studied data obtained previously from 20 COPD patients who, during routine follow-up, underwent a symptom-limited incremental exercise test and in whom a plethysmography was obtained concurrently. Air trapping at rest was assessed by measurement of the residual volume (RV) to total lung capacity (TLC) ratio (RV/TLC). Gas exchange data collected during the symptom-limited incremental cardiopulmonary exercise test allowed determination of the nadir and peak exercise values of V E/VCO 2 and V E/VO 2, thus enabling calculation of the difference between peak exrcise value and nadir values of  V E/VCO 2 and V E/VO 2, designated ΔV E/VCO 2 and ΔV E/VO 2, respectively. Results: We found a statistically significant inverse correlation between both ΔV E/VCO 2 (r = -0. 5058, 95% CI -0.7750 to -0.08149, p = 0.0234) and ΔV E/VO 2 (r = -0.5588, 95% CI -0.8029 to -0.1545, p = 0.0104) and the degree of air trapping (RV/TLC). There was no correlation between ΔV E/VCO 2 and forced expiratory volume in the first second, or body mass index.  Conclusions: The ventilatory equivalents increment to compensate for acidosis during incremental exercise testing was inversely correlated with air trapping (RV/TLC).

scholarly journals Ventilatory compensation during the incremental exercise test is inversely correlated with air trapping in COPD

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 1661
Author(s):  
Rottem Kuint ◽  
Neville Berkman ◽  
Samir Nusair
Keyword(s):  
Gas Exchange ◽  
Exercise Testing ◽  
Exercise Test ◽  
Cardiopulmonary Exercise Testing ◽  
Incremental Exercise ◽  
Peak Oxygen Consumption ◽  
Air Trapping ◽  
Incremental Exercise Test ◽  
Cardiopulmonary Exercise ◽  
Copd Patients

Background: Air trapping and gas exchange abnormalities are major causes of exercise limitation in chronic obstructive pulmonary disease (COPD). During incremental cardiopulmonary exercise testing, ventilatory equivalents for carbon dioxide (VE/VCO2) and oxygen (VE/VO2) may be difficult to identify in COPD patients because of limited ventilatory compensation capacity. Therefore, we aimed to detect a possible correlation between the magnitude of ventilation augmentation, as manifested by increments in ventilatory equivalents from nadir to peak effort values and air trapping, detected with static testing.    Methods: In this observational study, we studied data obtained previously from 20 COPD patients who, during routine follow-up, underwent a symptom-limited incremental exercise test and in whom a plethysmography was obtained concurrently. Air trapping at rest was assessed by measurement of the residual volume (RV) to total lung capacity (TLC) ratio (RV/TLC). Gas exchange data collected during the symptom-limited incremental cardiopulmonary exercise test allowed determination of the nadir and peak effort values of VE/VCO2 and VE/VO2, thus enabling calculation of the difference between peak effort value and nadir values of  VE/VCO2 and VE/VO2, designated ΔVE/VCO2 and ΔVE/VO2, respectively. Results: We found a statistically significant inverse correlation between both ΔVE/VCO2 (r = -0. 5058, 95% CI -0.7750 to -0.08149, p = 0.0234) and ΔVE/VO2 (r = -0.5588, 95% CI -0.8029 to -0.1545, p = 0.0104) and the degree of air trapping (RV/TLC). There was no correlation between                ΔVE/VCO2 and peak oxygen consumption, forced expiratory volume in the first second, or body mass index.  Conclusions: The ventilatory equivalents increment to compensate for acidosis during incremental exercise testing was inversely correlated with air trapping (RV/TLC) and may be a candidate prognostic biomarker.

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