scholarly journals Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers

1996 ◽  
Vol 81 (5) ◽  
pp. 1901-1907 ◽  
Author(s):  
Roland Favier ◽  
Esperanza Caceres ◽  
Laurent Guillon ◽  
Brigitte Sempore ◽  
Michel Sauvain ◽  
...  
Keyword(s):  
Heart Rate ◽  
Gas Exchange ◽  
Oxygen Uptake ◽  
Metabolic Responses ◽  
Physiological Data ◽  
Respiratory Gas Exchange ◽  
Gum Chewing ◽  
Arterial Blood ◽  
Before And After ◽  
Exercise Induced

Favier, Roland, Esperanza Caceres, Laurent Guillon, Brigitte Sempore, Michel Sauvain, Harry Koubi, and Hilde Spielvogel. Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers. J. Appl. Physiol. 81(5): 1901–1907, 1996.—To determine the effects of acute coca use on the hormonal and metabolic responses to exercise, 12 healthy nonhabitual coca users were submitted twice to steady-state exercise (∼75% maximal O2 uptake). On one occasion, they were asked to chew 15 g of coca leaves 1 h before exercise, whereas on the other occasion, exercise was performed after 1 h of chewing a sugar-free chewing gum. Plasma epinephrine, norepinephrine, insulin, glucagon, and metabolites (glucose, lactate, glycerol, and free fatty acids) were determined at rest before and after coca chewing and during the 5th, 15th, 30th, and 60th min of exercise. Simultaneously to these determinations, cardiorespiratory variables (heart rate, mean arterial blood pressure, oxygen uptake, and respiratory gas exchange ratio) were also measured. At rest, coca chewing had no effect on plasma hormonal and metabolic levels except for a significantly reduced insulin concentration. During exercise, the oxygen uptake, heart rate, and respiratory gas exchange ratio were significantly increased in the coca-chewing trial compared with the control (gum-chewing) test. The exercise-induced drop in plasma glucose and insulin was prevented by prior coca chewing. These results contrast with previous data obtained in chronic coca users who display during prolonged submaximal exercise an exaggerated plasma sympathetic response, an enhanced availability and utilization of fat (R. Favier, E. Caceres, H. Koubi, B. Sempore, M. Sauvain, and H. Spielvogel. J. Appl. Physiol. 80: 650–655, 1996). We conclude that, whereas coca chewing might affect glucose homeostasis during exercise, none of the physiological data provided by this study would suggest that acute coca chewing in nonhabitual users could enhance tolerance to exercise.

Central and regional circulatory adaptations to one-leg training

1982 ◽  
Vol 52 (4) ◽  
pp. 976-983 ◽  
Author(s):  
K. Klausen ◽  
N. H. Secher ◽  
J. P. Clausen ◽  
O. Hartling ◽  
J. Trap-Jensen
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Oxygen Uptake ◽  
Maximal Exercise ◽  
Exercise Heart Rate ◽  
Leg Blood Flow ◽  
Arterial Blood ◽  
Before And After ◽  
Leg Exercise

Six young healthy male subjects performed submaximal and maximal exercise on bicycle ergometers with one leg and two legs before and after 8 wk of one-leg training with each of both legs. The following variables were measured during one- and two-leg exercise: oxygen uptake, heart rate, mean arterial blood pressure, cardiac output, leg blood flow, and iliac arteriovenous differences for oxygen and lactate. After training the maximal oxygen uptake during one- and two-leg exercise was increased by 19 and 11%, respectively. The corresponding cardiac outputs increased by 16 and 11%, respectively. During submaximal one-leg exercise, heart rate decreased by 11%, whereas a decrease of only 2% was seen during submaximal two-leg exercise. Mean blood pressure decreased by about 10 Torr in both types of exercise and during both submaximal and maximal exercise. Maximal leg blood flow increased only by 1.2 l/min during one-leg exercise. Leg blood flow and leg oxygen uptake were smaller during two-leg exercise than during one-leg exercise and more so after training. These findings indicate that one-leg exercise, compared with two-leg exercise, involves circulatory adaptations that respond differently to one-leg training. The findings further imply that oxygen supply to one large muscle group of exercising muscles may be limited by vasoconstriction when another large group of muscles is exercising simultaneously.

Influence of inhaled nitric oxide on gas exchange during normoxic and hypoxic exercise in highly trained cyclists

2001 ◽  
Vol 90 (3) ◽  
pp. 926-932 ◽  
Author(s):  
A. William Sheel ◽  
Michael R. Edwards ◽  
Garth S. Hunte ◽  
Donald C. McKenzie
Keyword(s):  
Nitric Oxide ◽  
Heart Rate ◽  
Gas Exchange ◽  
Inhaled Nitric Oxide ◽  
Metabolic Parameters ◽  
Oxyhemoglobin Saturation ◽  
Arterial Blood ◽  
Hypoxic Fraction ◽  
Exercise Induced ◽  
Hypoxic Exercise

This study tested the effects of inhaled nitric oxide [NO; 20 parts per million (ppm)] during normoxic and hypoxic (fraction of inspired O2 = 14%) exercise on gas exchange in athletes with exercise-induced hypoxemia. Trained male cyclists ( n = 7) performed two cycle tests to exhaustion to determine maximal O2 consumption (V˙o 2 max) and arterial oxyhemoglobin saturation (SaO2 , Ohmeda Biox ear oximeter) under normoxic (V˙o 2 max = 4.88 ± 0.43 l/min and SaO2 = 90.2 ± 0.9, means ± SD) and hypoxic (V˙o 2 max = 4.24 ± 0.49 l/min and SaO2 = 75.5 ± 4.5) conditions. On a third occasion, subjects performed four 5-min cycle tests, each separated by 1 h at their respectiveV˙o 2 max, under randomly assigned conditions: normoxia (N), normoxia + NO (N/NO), hypoxia (H), and hypoxia + NO (H/NO). Gas exchange, heart rate, and metabolic parameters were determined during each condition. Arterial blood was drawn at rest and at each minute of the 5-min test. Arterial Po 2 (PaO2 ), arterial Pco 2, and SaO2 were determined, and the alveolar-arterial difference for Po 2 (A-aDo 2) was calculated. Measurements of PaO2 and SaO2 were significantly lower and A-aDo 2 was widened during exercise compared with rest for all conditions ( P < 0.05). No significant differences were detected between N and N/NO or between H and H/NO for PaO2 , SaO2 and A-aDo 2 ( P > 0.05). We conclude that inhalation of 20 ppm NO during normoxic and hypoxic exercise has no effect on gas exchange in highly trained cyclists.

Pulmonary gas exchange during exercise in women: effects of exercise type and work increment

2000 ◽  
Vol 89 (2) ◽  
pp. 721-730 ◽  
Author(s):  
Susan R. Hopkins ◽  
Rebecca C. Barker ◽  
Tom D. Brutsaert ◽  
Timothy P. Gavin ◽  
Pauline Entin ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Gas Exchange ◽  
Blood Gases ◽  
Random Order ◽  
Pulmonary Gas Exchange ◽  
Male Athletes ◽  
Prediction Limit ◽  
Fast Running ◽  
Arterial Blood ◽  
Exercise Induced

Exercise-induced arterial hypoxemia (EIAH) has been reported in male athletes, particularly during fast-increment treadmill exercise protocols. Recent reports suggest a higher incidence in women. We hypothesized that 1-min incremental (fast) running (R) protocols would result in a lower arterial Po 2 (PaO2 ) than 5-min increment protocols (slow) or cycling exercise (C) and that women would experience greater EIAH than previously reported for men. Arterial blood gases, cardiac output, and metabolic data were obtained in 17 active women [mean maximal O2 uptake (V˙o 2 max) = 51 ml · kg−1 · min−1]. They were studied in random order (C or R), with a fastV˙o 2 max protocol. After recovery, the women performed 5 min of exercise at 30, 60, and 90% ofV˙o 2 max (slow). One week later, the other exercise mode (R or C) was similarly studied. There were no significant differences in V˙o 2 maxbetween R and C. Pulmonary gas exchange was similar at rest, 30%, and 60% of V˙o 2 max. At 90% ofV˙o 2 max, PaO2 was lower during R (mean ± SE = 94 ± 2 Torr) than during C (105 ± 2 Torr, P < 0.0001), as was ventilation (85.2 ± 3.8 vs. 98.2 ± 4.4 l/min btps, P < 0.0001) and cardiac output (19.1 ± 0.6 vs. 21.1 ± 1.0 l/min, P < 0.001). Arterial Pco 2 (32.0 ± 0.5 vs. 30.0 ± 0.6 Torr, P < 0.001) and alveolar-arterial O2 difference (A-aDo 2; 22 ± 2 vs. 16 ± 2 Torr, P < 0.0001) were greater during R. PaO2 and A-aDo 2 were similar between slow and fast. Nadir PaO2 was ≤80 Torr in four women (24%) but only during fast-R. In all subjects, PaO2 atV˙o 2 max was greater than the lower 95% prediction limit calculated from available data in men ( n = 72 C and 38 R) for both R and C. These data suggest intrinsic differences in gas exchange between R and C, due to differences in ventilation and also efficiency of gas exchange. The PaO2 responses to R and C exercise in our 17 subjects do not differ significantly from those previously observed in men.

Comparative study on effect of neutral spinal bath and neutral spinal spray on blood pressure, heart rate and heart rate variability in healthy volunteers

2018 ◽  
Vol 16 (2) ◽  
Author(s):  
Arundhati Goley ◽  
A. Mooventhan ◽  
NK. Manjunath
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Healthy Volunteers ◽  
Group Analysis ◽  
Low Frequency ◽  
Single Session ◽  
Arterial Blood ◽  
Before And After ◽  
Instantaneous Heart Rate

Abstract Background Hydrotherapeutic applications to the head and spine have shown to improve cardiovascular and autonomic functions. There is lack of study reporting the effect of either neutral spinal bath (NSB) or neutral spinal spray (NSS). Hence, the present study was conducted to evaluate and compare the effects of both NSB and NSS in healthy volunteers. Methods Thirty healthy subjects were recruited and randomized into either neutral spinal bath group (NSBG) or neutral spinal spray group (NSSG). A single session of NSB, NSS was given for 15 min to the NSBG and NSSG, respectively. Assessments were taken before and after the interventions. Results Results of this study showed a significant reduction in low-frequency (LF) to high-frequency (HF) (LF/HF) ratio of heart rate variability (HRV) spectrum in NSBG compared with NSSG (p=0.026). Within-group analysis of both NSBG and NSSG showed a significant increase in the mean of the intervals between adjacent QRS complexes or the instantaneous heart rate (HR) (RRI) (p=0.002; p=0.009, respectively), along with a significant reduction in HR (p=0.002; p=0.004, respectively). But, a significant reduction in systolic blood pressure (SBP) (p=0.037) and pulse pressure (PP) (p=0.017) was observed in NSSG, while a significant reduction in diastolic blood pressure (DBP) (p=0.008), mean arterial blood pressure (MAP) (p=0.008) and LF/HF ratio (p=0.041) was observed in NSBG. Conclusion Results of the study suggest that 15 min of both NSB and NSS might be effective in reducing HR and improving HRV. However, NSS is particularly effective in reducing SBP and PP, while NSB is particularly effective in reducing DBP and MAP along with improving sympathovagal balance in healthy volunteers.

scholarly journals Quantitative assessment of the relationship between behavioral and autonomic dynamics during propofol-induced unconsciousness

2020 ◽  
Author(s):  
Sandya Subramanian ◽  
Patrick L. Purdon ◽  
Riccardo Barbieri ◽  
Emery N. Brown
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Prediction Models ◽  
Electrodermal Activity ◽  
Strong Relationship ◽  
Pulse Amplitude ◽  
Physiological Data ◽  
Statistical Tool ◽  
Autonomic Changes ◽  
Before And After

ABSTRACTDuring general anesthesia, both behavioral and autonomic changes are caused by the administration of anesthetics such as propofol. Propofol produces unconsciousness by creating highly structured oscillations in brain circuits. The anesthetic also has autonomic effects due to its actions as a vasodilator and myocardial depressant. Understanding how autonomic dynamics change in relation to propofol-induced unconsciousness is an important scientific and clinical question since anesthesiologists often infer changes in level of unconsciousness from changes in autonomic dynamics. Therefore, we present a framework combining physiology-based statistical models that have been developed specifically for heart rate variability and electrodermal activity with a robust statistical tool to compare behavioral and multimodal autonomic changes before, during, and after propofol-induced unconsciousness. We tested this framework on physiological data recorded from nine healthy volunteers during computer-controlled administration of propofol. We studied how autonomic dynamics related to behavioral markers of unconsciousness: 1) overall, 2) during the transitions of loss and recovery of consciousness, and 3) before and after anesthesia as a whole. Our results show a strong relationship between behavioral state of consciousness and autonomic dynamics. All of our prediction models showed areas under the curve greater than 0.75 despite the presence of non-monotonic relationships among the variables during the transition periods. Our analysis highlighted the specific roles played by fast versus slow changes, parasympathetic vs sympathetic activity, heart rate variability vs electrodermal activity, and even pulse rate vs pulse amplitude information within electrodermal activity. Further advancement upon this work can quantify the complex and subject-specific relationship between behavioral changes and autonomic dynamics before, during, and after anesthesia. However, this work demonstrates the potential of a multimodal, physiologically-informed, statistical approach to characterize autonomic dynamics.

scholarly journals Role of nitric oxide-containing factors in the ventilatory and cardiovascular responses elicited by hypoxic challenge in isoflurane-anesthetized rats

2014 ◽  
Vol 116 (11) ◽  
pp. 1371-1381 ◽  
Author(s):  
James P. Mendoza ◽  
Rachael J. Passafaro ◽  
Santhosh M. Baby ◽  
Alex P. Young ◽  
James N. Bates ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Heart Rate ◽  
Cardiovascular Responses ◽  
Vital Role ◽  
Initial Increase ◽  
Ventilatory Responses ◽  
Arterial Blood ◽  
Anesthetized Rats ◽  
Before And After

Exposure to hypoxia elicits changes in mean arterial blood pressure (MAP), heart rate, and frequency of breathing (fr). The objective of this study was to determine the role of nitric oxide (NO) in the cardiovascular and ventilatory responses elicited by brief exposures to hypoxia in isoflurane-anesthetized rats. The rats were instrumented to record MAP, heart rate, and fr and then exposed to 90 s episodes of hypoxia (10% O2, 90% N2) before and after injection of vehicle, the NO synthase inhibitor NG-nitro-l-arginine methyl ester (l-NAME), or the inactive enantiomer d-NAME (both at 50 μmol/kg iv). Each episode of hypoxia elicited a decrease in MAP, bidirectional changes in heart rate (initial increase and then a decrease), and an increase in fr. These responses were similar before and after injection of vehicle or d-NAME. In contrast, the hypoxia-induced decreases in MAP were attenuated after administration of l-NAME. The initial increases in heart rate during hypoxia were amplified whereas the subsequent decreases in heart rate were attenuated in l-NAME-treated rats. Finally, the hypoxia-induced increases in fr were virtually identical before and after administration of l-NAME. These findings suggest that NO factors play a vital role in the expression of the cardiovascular but not the ventilatory responses elicited by brief episodes of hypoxia in isoflurane-anesthetized rats. Based on existing evidence that NO factors play a vital role in carotid body and central responses to hypoxia in conscious rats, our findings raise the novel possibility that isoflurane blunts this NO-dependent signaling.

Parameters to Be Measured during Exercise

2018 ◽  
pp. 82-105
Author(s):  
Gregory S. Thomas ◽  
Myrvin H. Ellestad
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Myocardial Ischemia ◽  
Oxygen Uptake ◽  
Exercise Duration ◽  
Metabolic Equivalents ◽  
Include Blood Pressure ◽  
Electrocardiographic Changes ◽  
Health And Disease ◽  
Exercise Induced

The chapter Parameters to be Measured During Exercise reviews the physiologic changes with exercise which indicate health and disease. Key parameters include blood pressure, heart rate, electrocardiographic changes, exercise duration, maximum oxygen uptake (VO2max), and anaerobic threshold. An in-depth review and consensus estimate is provided to estimate metabolic equivalents (METs) achieved based on exercise duration on the Bruce and Ellestad protocols. Use of bipolar leads for detection of exercise induced myocardial ischemia is discussed, typified by CM5 which captures up to 90% of patients with an electrocardiographic manifestation of ischemia. Changes in murmurs that occur with exercise are reviewed; walk-through angina and chronotropic incompetence.

Aerobic work capacity in middle-aged Norwegian men

1965 ◽  
Vol 20 (3) ◽  
pp. 432-436 ◽  
Author(s):  
K. Lange Andersen ◽  
Lars Hermansen
Keyword(s):  
Heart Rate ◽  
Oxygen Uptake ◽  
Age Groups ◽  
Older Men ◽  
Work Capacity ◽  
Maximal Heart Rate ◽  
Middle Aged ◽  
Younger Age ◽  
Exercise Induced ◽  
Aerobic Work Capacity

Maximal oxygen uptake and related respiratory and circulatory functions were measured in sedentary and well-trained middle-aged men. Maximal oxygen uptakes averaged 2.63 liter/min in sedentary men and 3.36 liter/min in well-trained men, the latter value being essentially the same as found in young untrained students. The heart rate/ oxygen uptake relationship was found to be the same for sedentary-living men, regardless of age, but maximal heart rate was lower in older men. The maximal heart rate is probably the same in well-trained as in sedentary middle-aged men, this in contrast to what has been observed in younger age groups, where training reduces maximal heart rate. The exercise-induced hyperventilation takes place at an oxygen uptake corresponding to 70–80% of the capacity, this being the same in trained and untrained, and essentially the same as found in young adult subjects. maximal O2 uptake Submitted on March 23, 1964

scholarly journals Contribution of BKCa channels to local metabolic coronary vasodilation: effects of metabolic syndrome

2010 ◽  
Vol 298 (3) ◽  
pp. H966-H973 ◽  
Author(s):  
Léna Borbouse ◽  
Gregory M. Dick ◽  
Gregory A. Payne ◽  
Brittany D. Payne ◽  
Mark C. Svendsen ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Metabolic Syndrome ◽  
Heart Rate ◽  
Atherogenic Diet ◽  
Bkca Channels ◽  
Selective Blockade ◽  
Before And After ◽  
Lactate Uptake ◽  
Exercise Induced ◽  
The Relationship

This investigation was designed to examine the hypothesis that impaired function of coronary microvascular large-conductance Ca2+-activated K+ (BKCa) channels in metabolic syndrome (MetS) significantly attenuates the balance between myocardial oxygen delivery and metabolism at rest and during exercise-induced increases in myocardial oxygen consumption (MV̇o2). Studies were conducted in conscious, chronically instrumented Ossabaw swine fed a normal maintenance diet (11% kcal from fat) or an excess calorie atherogenic diet (43% kcal from fat, 2% cholesterol, 20% kcal from fructose) that induces many common features of MetS. Data were collected under baseline/resting conditions and during graded treadmill exercise before and after selective blockade of BKCa channels with penitrem A (10 μg/kg iv). We found that the exercise-induced increases in blood pressure were significantly elevated in MetS swine. No differences in baseline cardiac function or heart rate were noted. Induction of MetS produced a parallel downward shift in the relationship between coronary venous Po2 and MV̇o2 ( P < 0.001) that was accompanied by a marked release of lactate (negative lactate uptake) as MV̇o2 was increased with exercise ( P < 0.005). Inhibition of BKCa channels with penitrem A did not significantly affect blood pressure, heart rate, or the relationship between coronary venous Po2 and MV̇o2 in lean or MetS swine. These data indicate that BKCa channels are not required for local metabolic control of coronary blood flow under physiological (lean) or pathophysiological (MetS) conditions. Therefore, diminished function of BKCa channels does not contribute to the impairment of myocardial oxygen-supply demand balance in MetS.

Role of sinoaortic reflexes in hemodynamic patterns of natural defense behaviors in the cat

1981 ◽  
Vol 240 (3) ◽  
pp. H421-H429 ◽  
Author(s):  
G. Baccelli ◽  
R. Albertini ◽  
A. Del Bo ◽  
G. Mancia ◽  
A. Zanchetti
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Carotid Sinus ◽  
Emotional Behavior ◽  
Natural Defense ◽  
Arterial Blood ◽  
Hemodynamic Pattern ◽  
Before And After

To evaluate whether sinoaortic afferents contribute to the hemodynamic pattern of fighting, cardiovascular changes associated with fighting were studied in cats before and after sinoaortic denervation. Sinoaortic denervation exaggerates the decrease in heart rate, cardiac output, and arterial pressure during immobile confrontation (hissing, staring but no movement). During nonsupportive fighting (fighting with forelimbs while lying on one side) and supportive fighting ( fighting while standing on four feet) sinoaortic denervation reduces the increase in heart rate and cardiac output, minimizes the mesenteric vasoconstriction, induces a fall in arterial blood pressure, but does not affect iliac vasoconstriction or vasodilatation. The hemodynamic pattern of fighting is similarly changed by temporary inactivation of carotid sinus baroreflexes by common carotid occlusion as by chronic section of sinoaortic nerves. It is concluded that sinoaortic reflexes play an important role in the cardiovascular patterns accompanying natural fighting. They favor cardiac action and allow a marked visceral vasoconstriction to occur, thus minimizing or preventing a fall in blood pressure during emotional behavior.

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