scholarly journals Evaluation of Oxygen Uptake Kinetic Asymmetries in Patients with Multiple Sclerosis: A Pilot Study

2018 ◽  
Vol 6 (4) ◽  
pp. 21
Author(s):  
Rebecca D. Larson ◽  
Monica Barton ◽  
John W Farrell III ◽  
Gregory S. Cantrell ◽  
David J. Lantis ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Oxygen Uptake ◽  
Peak Oxygen Uptake ◽  
Mineral Density ◽  
Uptake Kinetic ◽  
Mean Response Time ◽  
Vo2 Kinetics ◽  
Constant Work Rate ◽  
Power Peak ◽  
Response To Exercise

Background of Study: Observations of limb to limb differences (bilateral asymmetry) in leg strength, power, peak oxygen uptake (VO2) and bone mineral density has been reported in individuals with Multiple Sclerosis (MS). Objetives: The purpose of this study was to quantify the magnitude of bilateral asymmetries in oxygen uptake (VO2) kinetics response to single leg cycling (SLC) in relapsing-remitting multiple sclerosis (MS) patients. Methods: Five MSpatients (2 men, 3 women; age 43±7 yrs) performed constant work rate SLC trials to determine VO2 kinetics in each leg. Asymmetry scores were used to quantify the magnitude of the bilateral asymmetries. Results: Significant asymmetries were seen in VO2 peak and parameters of VO2 kinetics. VO2peak asymmetry score was significantly different than 0% (p=0.015). Similarly,significant asymmetry for VO2 kinetic response to exercise as mean response time was observed (p=0.03). In addition the VO2 response to exercise resulted in a significant asymmetry in VO2 deficit between legs (p=0.03). No correlation between EDSS scores and any asymmetry scores existed. Conclusions: These findings provide insight into the potential differences in metabolic perturbation and limb specific symptomatic fatigue within the MS population.

scholarly journals Longitudinal Changes in the Oxygen Uptake Kinetic Response to Heavy-Intensity Exercise in 14- to 16-Year-Old Boys

2010 ◽  
Vol 22 (2) ◽  
pp. 314-325 ◽  
Author(s):  
Brynmor C. Breese ◽  
Craig A. Williams ◽  
Alan R. Barker ◽  
Joanne R. Welsman ◽  
Samantha G. Fawkner ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Slow Component ◽  
Uptake Kinetic ◽  
Pulmonary Oxygen Uptake ◽  
Longitudinal Changes ◽  
Age Dependent ◽  
Constant Work Rate ◽  
Exercise Transitions ◽  
The Difference ◽  
Gas Exchange Threshold

This study examined longitudinal changes in the pulmonary oxygen uptake (pV̇O2) kinetic response to heavy-intensity exercise in 14–16 yr old boys. Fourteen healthy boys (age 14.1 ± 0.2 yr) completed exercise testing on two occasions with a 2-yr interval. Each participant completed a minimum of three ‘step’ exercise transitions, from unloaded pedalling to a constant work rate corresponding to 40% of the difference between the pV̇O2 at the gas exchange threshold and peak pV̇O2 (40% Δ). Over the 2-yr period a significant increase in the phase II time constant (25 ± 5 vs. 30 ± 5 s; p = .002, ω2 = 0.34), the relative amplitude of the pV̇O2 slow component (9 ± 5 vs. 13 ± 4%; p = .036, ω2 = 0.14) and the pV̇O2 gain at end-exercise (11.6 ± 0.6 vs. 12.4 ± 0.7 mL·min−1·W−1; p < .001, ω2 = 0.42) were observed. These data indicate that the control of oxidative phosphorylation in response to heavy-intensity cycling exercise is age-dependent in teenage boys.

scholarly journals Box-Jenkins Transfer Function Modelling for Reliable Determination of VO2 Kinetics in Patients with COPD

2019 ◽  
Vol 9 (9) ◽  
pp. 1822 ◽  
Author(s):  
Joren Buekers ◽  
Jan Theunis ◽  
Alberto Peña Fernández ◽  
Emiel F. M. Wouters ◽  
Martijn A. Spruit ◽  
...  
Keyword(s):  
Transfer Function ◽  
Mean Squared Error ◽  
Kinetic Feature ◽  
Reliable Determination ◽  
Exponential Models ◽  
Mean Response Time ◽  
Vo2 Kinetics ◽  
Constant Work Rate ◽  
Function Modelling ◽  
Feature Values

Oxygen uptake (VO2) kinetics provide information about the ability to respond to the increased physical load during a constant work rate test (CWRT). Box-Jenkins transfer function (BJ-TF) models can extract kinetic features from the phase II VO2 response during a CWRT, without being affected by unwanted noise contributions (e.g., phase I contribution or measurement noise). CWRT data of 18 COPD patients were used to compare model fits and kinetic feature values between BJ-TF models and three typically applied exponential modelling methods. Autocorrelation tests and normalised root-mean-squared error values (BJ-TF: 2.8 ± 1.3%; exponential methods A, B and C: 10.5 ± 5.8%, 11.3 ± 5.2% and 12.1 ± 7.0%; p < 0.05) showed that BJ-TF models, in contrast to exponential models, could account for the most important noise contributions. This led to more reliable kinetic feature values compared to methods A and B (e.g., mean response time (MRT), BJ-TF: 74 ± 20 s; methods A-B: 100 ± 56 s–88 ± 52 s; p < 0.05). Only exponential modelling method C provided kinetic feature values comparable to BJ-TF features values (e.g., MRT: 75 ± 20 s). Based on theoretical considerations, we recommend using BJ-TF models, rather than exponential models, for reliable determinations of VO2 kinetics.

scholarly journals Oxygen Uptake On-Kinetics during Low-Intensity Resistance Exercise: Effect of Exercise Mode and Load

2019 ◽  
Vol 16 (14) ◽  
pp. 2524 ◽  
Author(s):  
Victor M. Reis ◽  
Eduardo B. Neves ◽  
Nuno Garrido ◽  
Ana Sousa ◽  
André L. Carneiro ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Resistance Exercise ◽  
Bench Press ◽  
Slow Component ◽  
Kinetics Parameters ◽  
Leg Extension ◽  
Low Intensity ◽  
Vo2 Kinetics ◽  
Exercise Effect ◽  
Constant Work Rate

Oxygen uptake (VO2) kinetics has been analyzed through mathematical modeling of constant work-rate exercise, however, the exponential nature of the VO2 response in resistance exercise is currently unknown. The present work assessed the VO2 on-kinetics during two different sub maximal intensities in the inclined bench press and in the seated leg extension exercise. Twelve males (age: 27.2 ± 4.3 years, height: 177 ± 5 cm, body mass: 79.0 ± 10.6 kg and estimated body fat: 11.4 ± 4.1%) involved in recreational resistance exercise randomly performed 4-min transitions from rest to 12% and 24% of 1 repetition maximum each, of inclined bench press (45°) and leg extension exercises. During all testing, expired gases were collected breath-by-breath with a portable gas analyzer (K4b2, Cosmed, Italy) and VO2 on-kinetics were identified using a multi-exponential mathematical model. Leg extension exercise exhibited a higher R-square, compared with inclined bench press, but no differences were found in-between exercises for the VO2 kinetics parameters. VO2 on-kinetics seems to be more sensitive to muscle related parameters (upper vs. lower body exercise) and less to small load variations in the resistance exercise. The absence of a true slow component indicates that is possible to calculate low-intensity resistance exercise energy cost based solely on VO2 measurements.

Oxygen Uptake Kinetic Response to Exercise in Children

2003 ◽  
Vol 33 (9) ◽  
pp. 651-669 ◽  
Author(s):  
Samantha G Fawkner ◽  
Neil Armstrong
Keyword(s):  
Oxygen Uptake ◽  
Uptake Kinetic ◽  
Oxygen Uptake Kinetic ◽  
Response To Exercise

scholarly journals Longitudinal Changes in the Oxygen Uptake Kinetic Response to Heavy-Intensity Exercise in 14- to 16-Year-Old Boys

2010 ◽  
Vol 22 (1) ◽  
pp. 69-80 ◽  
Author(s):  
Brynmor C. Breese ◽  
Craig A. Williams ◽  
Alan R. Barker ◽  
Joanne R. Welsman ◽  
Samantha G. Fawkner ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Slow Component ◽  
Uptake Kinetic ◽  
Pulmonary Oxygen Uptake ◽  
Longitudinal Changes ◽  
Age Dependent ◽  
Constant Work Rate ◽  
Exercise Transitions ◽  
The Difference ◽  
Gas Exchange Threshold

This study examined longitudinal changes in the pulmonary oxygen uptake (pV̇O2) kinetic response to heavy-intensity exercise in 14–16 yr old boys. Fourteen healthy boys (age 14.1 ± 0.2 yr) completed exercise testing on two occasions with a 2-yr interval. Each participant completed a minimum of three ‘step’ exercise transitions, from unloaded pedalling to a constant work rate corresponding to 40% of the difference between the pV̇O2 at the gas exchange threshold and peak pV̇O2 (Δ). Over the 2-yr period a significant increase in the phase II time constant (25 ± 5 vs. 30 ± 5 s; p = .002, ω2 = 0.34), the relative amplitude of the pV̇O2 slow component (9 ± 5 vs. 13 ± 4%; p = .036, ω2 = 0.14) and the pV̇O2 gain at end-exercise (11.6 ± 0.6 vs. 12.4 ± 0.7 mL·min−1·W−1; p < .001, ω2 = 0.42) were observed. These data indicate that the control of oxidative phosphorylation in response to heavy-intensity cycling exercise is age-dependent in teenage boys.

The impact of age and socioeconomic factors on response to exercise training in patients with ischemic heart disease, heart failure and after valve replacement

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
H.K Rasmusen ◽  
N Mikkelsen
Keyword(s):  
Logistic Regression ◽  
Regression Analysis ◽  
Heart Disease ◽  
Exercise Training ◽  
Oxygen Uptake ◽  
Peak Oxygen Uptake ◽  
Funding Source ◽  
Baseline Characteristics ◽  
Response To Exercise ◽  
The Impact

Abstract   The impact of baseline characteristics on response to exercise training in patients with ischemic heart disease. Background Exercise training improves peak oxygen uptake, an important predictor of mortality in patients with coronary artery disease (CAD). Unfortunately, some patients do not response with an increase in peak oxygen uptake after exercise training. If it is possible to identify these patients it would be possible to tailor their exercise training. Purpose To investigate if baseline characteristics can predict response to exercise training in patients with heart disease. Methods A retrospective analysis of 1443 CAD patients (age 64±11 y (mean (±SD)), 74% male, participated and completed an eight-week supervised outpatient exercise intervention with two weekly training sessions of 1.5 hours with high intensity interval- (&gt;80% of VO2peak) and resistance training. Patient characteristics were entered in the local database as the patients entered cardiac rehabilitation (CR). VO2peak was assessed before and after CR using a cardiopulmonary exercise test (CPET) with a maximal symptom limited bicycle ergometer test. Breathing gases were collected and analysed breath-by-breath. Each test aimed at physical exhaustion and a respiratory exchange ratio of more than 1.1 to ensure the validity of the CPET test. Patients were divided into responders defined as an improvement in aerobic capacity (change in VO2peak) after CR and non-responders if no improvement (change in VO2peak of 0.0ml/kg/min or less) post CR. We performed a multivariable logistic regression analysis using responders vs. non-responders as the endpoint. Explanatory variables were identified according to previous literature and comprised the following variables; age, sex, baseline VO2peak, tobacco use, diabetes, COPD, revascularization, working status, educational attainment, ethnicity and hypercholesteremia. Results 1097 patients were responders and 346 (24%) non-responders to the exercise training despite no difference in attendance. Logistic regression analysis of responders vs. non-responders in relation to baseline characteristics are shown in the table. Conclusion In summarize, 24% of these heart patients were exercise non-responders. High baseline VO2peak, older age, having COPD, being on disability pension, low educational attainment and non-western ethnicity were predictors of training non-response. Identification of patients with a large likelihood of non-response is a beginning towards patient tailored exercise programmes. Baseline characteristics in responders. CABG: coronary artery bypass graft; COPD: chronic obstructive pulmonary disease; PCI: percutaneous coronary intervention; SD: standard deviation; VO2peak: change in peak oxygen uptake. P-values of &lt;0.05 are considered significant and shown in bold. 95% confidence intervals are shown in last column. Funding Acknowledgement Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Helsefonden

Effect of acute nitrate ingestion on V̇O2 response at different exercise intensity domains

2017 ◽  
Vol 42 (11) ◽  
pp. 1127-1134 ◽  
Author(s):  
Thaysa Ghiarone ◽  
Thays Ataide-Silva ◽  
Romulo Bertuzzi ◽  
Glenn Kevin McConell ◽  
Adriano Eduardo Lima-Silva
Keyword(s):  
Oxygen Uptake ◽  
Exercise Intensity ◽  
Slow Component ◽  
Peak Oxygen Uptake ◽  
Time To Exhaustion ◽  
Severe Exercise ◽  
Nitrate Supplementation ◽  
The Difference ◽  
Response To Exercise ◽  
Gas Exchange Threshold

While nitrate supplementation influences oxygen uptake (V̇O2) response to exercise, this effect may be intensity dependent. The purpose of this study was to investigate the effect of acute nitrate supplementation on V̇O2 response during different exercise intensity domains in humans. Eleven men ingested 10 mg·kg−1 body mass (8.76 ± 1.35 mmol) of sodium nitrate or sodium chloride (placebo) 2.5 h before cycling at moderate (90% of gas exchange threshold; GET), heavy (GET + 40% of the difference between GET and peak oxygen uptake (V̇O2peak), Δ 40) or severe (GET + 80% of the difference between GET and V̇O2peak, Δ 80) exercise intensities. Volunteers performed exercise for 10 min (moderate), 15 min (heavy) or until exhaustion (severe). Acute nitrate supplementation had no effect on any V̇O2 response parameters during moderate and severe exercise intensities. However, the V̇O2 slow amplitude (nitrate: 0.93 ± 0.36 L·min−1 vs. placebo: 1.13 ± 0.59 L·min−1, p = 0.04) and V̇O2 slow gain (nitrate: 5.81 ± 2.37 mL·min–1·W−1 vs. placebo: 7.09 ± 3.67 mL·min–1·W−1, p = 0.04) were significantly lower in nitrate than in placebo during the heavy exercise intensity. There was no effect of nitrate on plasma lactate during any exercise intensity (p > 0.05). Time to exhaustion during the severe exercise intensity was also not affected by nitrate (p > 0.05). In conclusion, acute nitrate supplementation reduced the slow component of V̇O2 only when performing heavy-intensity exercise, which might indicate an intensity-dependent effect of nitrate on V̇O2 response.

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