Exercise endurance and arterial desaturation in normobaric hypoxia with increased chemosensitivity

1991 ◽  
Vol 70 (4) ◽  
pp. 1770-1774 ◽  
Author(s):  
G. G. Giesbrecht ◽  
A. Puddy ◽  
M. Ahmed ◽  
M. Younes ◽  
N. R. Anthonisen
Keyword(s):  
Cycle Ergometer ◽  
Normobaric Hypoxia ◽  
Endurance Time ◽  
Almitrine Bismesylate ◽  
Air Breathing ◽  
Warm Up ◽  
Exercise Endurance ◽  
Arterial O2 Saturation ◽  
Hypoxic Exercise ◽  
Rest And Exercise

We studied whether exercise endurance under normobaric hypoxia can be enhanced by increasing hypoxic ventilatory sensitivity with almitrine bismesylate (ALM). On both ALM and placebo (PL) days, resting subjects breathed a hypoxic gas mixture (an inspired O2 fraction of 10.4-13.2%), which lowered resting arterial O2 saturation (SaO2) to 80%. After 15 min of rest there was a 3-min warm-up period of exercise at 50 W (light) on a cycle ergometer, followed by a step increase in load to 60% of the previously determined maximum power output with room-air breathing (moderate), which was maintained until exhaustion. With PL, SaO2 decreased rapidly with the onset of exercise and continued to fall slowly during moderate exercise, averaging 71.0 +/- 1.8% (SE) at exhaustion. With ALM, saturation did not differ from PL during air breathing but significantly exceeded SaO2 with PL, by 3.4% during resting hypoxia, by 4.0% at the start of exercise, and by 5.9% at exhaustion. Ventilation was not affected by ALM during air breathing and was slightly, although not significantly, increased during hypoxic rest and exercise. ALM was associated with an increased heart rate during room air breathing but not during hypoxia. Endurance time was 20.6 +/- 1.6 min with ALM and 21.3 +/- 0.9 min with PL. During hypoxic exercise, the potential benefit of greater saturation with ALM is apparently offset by other unidentified factors.

Neuropeptide Y release from human heart is enhanced during prolonged exercise in hypoxia

1994 ◽  
Vol 76 (3) ◽  
pp. 1346-1349 ◽  
Author(s):  
L. Kaijser ◽  
J. Pernow ◽  
B. Berglund ◽  
J. Grubbstrom ◽  
J. M. Lundberg
Keyword(s):  
Neuropeptide Y ◽  
Coronary Sinus ◽  
Cycle Ergometer ◽  
Air Breathing ◽  
Ergometer Exercise ◽  
The Difference ◽  
Exercise Induced ◽  
Arterial O2 Saturation ◽  
Net Release ◽  
Coronary Sinus Blood

To evaluate the effect of hypoxemia on cardiac release of neuropeptide Y-like immunoreactivity (NPY-LI) and norepinephrine (NE), arterial and coronary sinus blood was sampled and coronary sinus blood flow was measured by thermodilution in nine healthy volunteers at rest and during supine cycle ergometer exercise while they breathed air and 12% O2, which reduced arterial O2 saturation to approximately 68%. Five subjects started to exercise for 30 min breathing air and continued for 30 min breathing 12% O2; four subjects breathed 12% O2 and air in the reverse order. The load was adjusted to give the same heart rate during O2 and air breathing. No significant cardiac net release of NPY-LI or NE was seen at rest. Exercise induced release of NPY-LI and NE. The net release of NPY-LI was 0.7 +/- 0.4 pmol/min during air breathing (average 12 and 30 min) and 2.8 +/- 0.6 pmol/min during 12% O2 breathing. The difference was not influenced by the order of the breathing periods. The NE coronary sinus-arterial difference was not significantly different between 12% O2 and air breathing, whereas the net release was significantly larger during 12% O2 breathing (0.6 +/- 0.1 vs. 0.4 +/- 0.1 nmol/min). Thus, NPY is released with NE from the heart during exercise. Arterial hypoxemia seems to be an additional stimulus of preferential NPY release.

scholarly journals The Wingate Anaerobic Test, a Narrative Review of the Protocol Variables That Affect the Results Obtained

2021 ◽  
Vol 11 (16) ◽  
pp. 7417
Author(s):  
Arkaitz Castañeda-Babarro
Keyword(s):  
Literature Search ◽  
Web Of Science ◽  
Cycle Ergometer ◽  
Narrative Review ◽  
Improve Performance ◽  
Wingate Anaerobic Test ◽  
Warm Up ◽  
Cycling Test ◽  
Anaerobic Test

The Wingate Anaerobic Test (WAT) has been widely used since its creation in 1974. The WAT involves performing a 30 s “all-out” cycling test. The test is currently applied with some modifications, partly due to the evolution of the material used to perform it. The purpose of this text is to act as a guide for the correct use and application of the test, as well as to highlight the importance of controlling many of the variables that may influence its results. Methods: A literature search was conducted in PUBMED/MEDLINE and Web of Science with different combinations of keywords all related to the WAT to obtain a search of 113 papers. Results and discussion: It was observed that variables such as the duration of the test or the resistance used in the cycle ergometer must be adjusted according to the objective and the population evaluated, while others such as the warm-up or the supplementation of different substances can improve performance on the WAT. Conclusions: In order to apply the WAT correctly, variables such as duration, resistance used or warm-up time and intensity must be adjusted according to the evaluated subjects and the aim of the study. Other variables such as position on the bike or equipment used should also be controlled if we want to guarantee its replicability.

scholarly journals Effects of umeclidinium/vilanterol on exercise endurance in COPD: a randomised study

2018 ◽  
Vol 4 (1) ◽  
pp. 00073-2017 ◽  
Author(s):  
John H. Riley ◽  
Chris J. Kalberg ◽  
Alison Donald ◽  
David A. Lipson ◽  
Muhammad Shoaib ◽  
...  
Keyword(s):  
Forced Expiratory Volume ◽  
Chronic Obstructive ◽  
Post Dose ◽  
Double Blind ◽  
Endurance Time ◽  
Obstructive Pulmonary Disease ◽  
Once Daily ◽  
Randomised Study ◽  
Residual Capacity ◽  
Exercise Endurance

This multicentre, randomised, double-blind, placebo-controlled, two-period crossover study assessed the effect of umeclidinium/vilanterol (UMEC/VI) on exercise capacity in patients with chronic obstructive pulmonary disease (COPD) using the endurance shuttle walk test (ESWT).Patients were randomised 1:1 to one of two treatment sequences: 1) UMEC/VI 62.5/25 µg followed by placebo or 2) placebo followed by UMEC/VI 62.5/25 µg. Each treatment was taken once daily for 12 weeks. The primary end-point was 3-h post-dose exercise endurance time (EET) at week 12. Secondary end-points included trough forced expiratory volume in 1 s (FEV1) and 3-h post-dose functional residual capacity (FRC), both at week 12. COPD Assessment Test (CAT) score at week 12 was also assessed.UMEC/VI treatment did not result in a statistically significant improvement in EET change from baseline at week 12 versus placebo (p=0.790). However, improvements were observed in trough FEV1 (206 mL, 95% CI 167–246), 3-h post-dose FRC (−346 mL, 95% CI −487 to −204) and CAT score (−1.07 units, 95% CI −2.09 to −0.05) versus placebo at week 12.UMEC/VI did not result in improvements in EET at week 12 versus placebo, despite improvements in measures of lung function, hyperinflation and health status.

Effect of hypoxic exercise on glucose tolerance in healthy and prediabetic adults

2021 ◽  
Vol 320 (1) ◽  
pp. E43-E54
Author(s):  
Estelle De Groote ◽  
Florian A. Britto ◽  
Estelle Balan ◽  
Geoffrey Warnier ◽  
Jean-Paul Thissen ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Glucose Metabolism ◽  
Glucose Tolerance ◽  
Healthy Subjects ◽  
Molecular Mechanisms ◽  
Acute Exercise ◽  
Normobaric Hypoxia ◽  
Hypoxic Exercise

The molecular mechanisms involved in glucose tolerance after acute exercise in hypoxia have not yet been elucidated in human. Due to the reversible character of their status, prediabetic individuals are of particular interest for preventing the development of type 2 diabetes. The present study is the first to investigate muscle molecular mechanisms during exercise and glucose metabolism after exercise in prediabetic and healthy subjects exercising in normoxia and normobaric hypoxia.

Reliability of Effort Perception for Regulating Exercise Intensity in Children Using the Cart and Load Effort Rating (CALER) Scale

2000 ◽  
Vol 12 (4) ◽  
pp. 388-397 ◽  
Author(s):  
Roger G. Eston ◽  
Gaynor Parfitt ◽  
Laura Campbell ◽  
Kevin L. Lamb
Keyword(s):  
Young Children ◽  
Exercise Intensity ◽  
Intraclass Correlation ◽  
Preliminary Evidence ◽  
Cycle Ergometer ◽  
Limits Of Agreement ◽  
Warm Up ◽  
Effort Perception ◽  
Objective Feedback ◽  
Effort Rating

The purpose of this study was to assess whether young children could reliability regulate exercise intensity production after several practice trials, without reference to objective feedback measures. The study used a new 10-point scale (Cart and Load Effort Rating [CALER] Scale), which depicts a child on a bicycle, at various stages of exertion, towing a cart in which the load increases progressively. After warm-up, 20 children, aged 7–10 years, performed an intermittent, effort production protocol at CALER 2, 5, and 8 on a cycle ergometer. This was repeated on three further occasions in the next 4 weeks. An increase in PO across trials (44, 65, and 79 W at CALER 2, 5, and 8, respectively) confirmed that the children understood the scale. A Bland and Altman limits of agreement (LoA) analysis and an intraclass correlation analysis (ICC) between trials (T) indicated that reliability improved with practice. Intertrial comparisons of overall reliability from T1 to T2 and from T3 to T4 ranged from 0.76 to 0.97 and an improvement in the overall bias ± 95% limits of agreement from −12 ± 19 W to 0 ± 10 W. This study is the first to apply more than two repeated effort production trials in young children and provides strong evidence that practice improves the reliability of effort perception in children. The data also provide preliminary evidence for the validity of the CALER Scale in children aged 7–10 years.

Prior heavy-intensity exercise speeds V̇o2 kinetics during moderate-intensity exercise in young adults

2005 ◽  
Vol 98 (4) ◽  
pp. 1371-1378 ◽  
Author(s):  
Brendon J. Gurd ◽  
Barry W. Scheuermann ◽  
Donald H. Paterson ◽  
John M. Kowalchuk
Keyword(s):  
Young Adults ◽  
Lactate Threshold ◽  
Near Infrared ◽  
Linear Regression Analysis ◽  
Cycle Ergometer ◽  
Moderate Intensity ◽  
Moderate Intensity Exercise ◽  
Warm Up ◽  
Total Hemoglobin ◽  
Concentration Changes

The effect of prior heavy-intensity warm-up exercise on subsequent moderate-intensity phase 2 pulmonary O2 uptake kinetics (τV̇o2) was examined in young adults exhibiting relatively fast (FK; τV̇o2 < 30 s; n = 6) and slow (SK; τV̇o2 > 30 s; n = 6) V̇o2 kinetics in moderate-intensity exercise without prior warm up. Subjects performed four repetitions of a moderate (Mod1)-heavy-moderate (Mod2) protocol on a cycle ergometer with work rates corresponding to 80% estimated lactate threshold (moderate intensity) and 50% difference between lactate threshold and peak V̇o2 (heavy intensity); each transition lasted 6 min, and each was preceded by 6 min of cycling at 20 W. V̇o2 and heart rate (HR) were measured breath-by-breath and beat-by-beat, respectively; concentration changes of muscle deoxyhemoglobin (HHb), oxyhemoglobin, and total hemoglobin were measured by near-infrared spectroscopy (Hamamatsu NIRO 300). τV̇o2 was lower ( P < 0.05) in Mod2 than in Mod1 in both FK (20 ± 5 s vs. 26 ± 5 s, respectively) and SK (30 ± 8 s vs. 45 ± 11 s, respectively); linear regression analysis showed a greater “speeding” of V̇o2 kinetics in subjects exhibiting a greater Mod1 τV̇o2. HR, oxyhemoglobin, and total hemoglobin were elevated ( P < 0.05) in Mod2 compared with Mod1. The delay before the increase in HHb was reduced ( P < 0.05) in Mod2, whereas the HHb mean response time was reduced ( P < 0.05) in FK (Mod2, 22 ± 3 s; Mod1, 32 ± 11 s) but not different in SK (Mod2, 36 ± 13 s; Mod1, 34 ± 15 s). We conclude that improved muscle perfusion in Mod2 may have contributed to the faster adaptation of V̇o2, especially in SK; however, a possible role for metabolic inertia in some subjects cannot be overlooked.

Oxidation rates of orally ingested carbohydrates during prolonged exercise in men

1993 ◽  
Vol 75 (6) ◽  
pp. 2774-2780 ◽  
Author(s):  
A. J. Wagenmakers ◽  
F. Brouns ◽  
W. H. Saris ◽  
D. Halliday
Keyword(s):  
Oxidation Rate ◽  
Prolonged Exercise ◽  
Work Load ◽  
Cycle Ergometer ◽  
Total Carbohydrate ◽  
Warm Up ◽  
Oxidation Rates ◽  
All Solutions ◽  
Glucose Polymer ◽  
S Oxidation

Six male volunteers exercised on a cycle ergometer at 65% of maximal work load for 120 min on six occasions while ingesting water (W) only, four doses of maltodextrin (M) [0.92, 1.85, 2.77, and 3.70 g/kg body wt (4, 8, 12, and 16% M, respectively)], and sucrose (S) [1.85 g/kg body wt (8% S)]. Drinks were given during warm-up (8 ml/kg body wt) and each 15 min during exercise (2 ml/kg body wt). M and S were of high 13C natural abundance. Total carbohydrate (CHO) and fat oxidations were calculated from the nonprotein respiratory exchange ratio. M and S increased total CHO oxidation compared with W; no difference was observed between CHO solutions. Total CHO oxidation decreased continuously with time and more rapidly after W than after M or S. Fat oxidation increased continuously in all treatments. Oxidation rates of ingested CHO were 52 +/- 19, 76 +/- 12, 86 +/- 10, and 91 +/- 9 g/2 h for 4, 8, 12, and 16% M, respectively. The oxidation rate of S was 81 +/- 10 g/2 h (not different from 8% M), which indicated that the glucose polymer had no advantage over S. Oxidation rates of M and S increased to a plateau after 90–120 min of exercise. For all solutions except 4% M, the plateau oxidation rate was close to 1.0 g/min. Differences between 8, 12, and 16% M and 8% S were minimal such that ingestion of 8% M or S may well have had an optimal ergogenic effect.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Effect of combination treatment on lung volumes and exercise endurance time in COPD

2012 ◽  
Vol 106 (10) ◽  
pp. 1413-1420 ◽  
Author(s):  
Helgo Magnussen ◽  
Pierluigi Paggiaro ◽  
Hendrik Schmidt ◽  
Steven Kesten ◽  
Norbert Metzdorf ◽  
...  
Keyword(s):  
Combination Treatment ◽  
Endurance Time ◽  
Lung Volumes ◽  
Exercise Endurance

scholarly journals Effect of morphine on breathlessness and exercise endurance in advanced COPD: a randomised crossover trial

2017 ◽  
Vol 50 (4) ◽  
pp. 1701235 ◽  
Author(s):  
Sara J. Abdallah ◽  
Courtney Wilkinson-Maitland ◽  
Nathalie Saad ◽  
Pei Zhi Li ◽  
Benjamin M. Smith ◽  
...  
Keyword(s):  
Crossover Trial ◽  
Oral Morphine ◽  
Immediate Release ◽  
Acute Effect ◽  
Constant Load ◽  
Chronic Obstructive ◽  
Cycle Exercise ◽  
Endurance Time ◽  
Obstructive Pulmonary Disease ◽  
Exercise Endurance

The objective of the present study was to evaluate the effect of morphine on exertional breathlessness and exercise endurance in advanced chronic obstructive pulmonary disease (COPD).In a randomised crossover trial, we compared the acute effect of immediate-release oral morphineversusplacebo on physiological and perceptual responses during constant-load cardiopulmonary cycle exercise testing (CPET) in 20 adults with advanced COPD and chronic breathlessness syndrome.Compared with placebo, morphine reduced exertional breathlessness at isotime by 1.2±0.4 Borg units and increased exercise endurance time by 2.5±0.9 min (both p≤0.014). During exercise at isotime, morphine decreased ventilation by 1.3±0.5 L·min−1and breathing frequency by 2.0±0.9 breaths·min−1(both p≤0.041). Compared with placebo, morphine decreased exertional breathlessness at isotime by ≥1 Borg unit in 11 participants (responders) and by <1 Borg unit in nine participants (non-responders). Baseline participant characteristics, including pulmonary function and cardiorespiratory fitness, were similar between responders and non-responders. A higher percentage of respondersversusnon-responders stopped incremental CPET due to intolerable breathlessness: 82versus33% (p=0.028).Immediate-release oral morphine improved exertional breathlessness and exercise endurance in some, but not all, adults with advanced COPD. The locus of symptom-limitation on laboratory-based CPET may help to identify patients most likely to benefit from morphine.

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