scholarly journals Heart rates and swim speeds of emperor penguins diving under sea ice

1992 ◽  
Vol 165 (1) ◽  
pp. 161-180 ◽  
Author(s):  
G. L. Kooyman ◽  
P. J. Ponganis ◽  
M. A. Castellini ◽  
E. P. Ponganis ◽  
K. V. Ponganis ◽  
...  
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Sea Ice ◽  
Body Mass ◽  
Anaerobic Glycolysis ◽  
Energy Contribution ◽  
Heart Rates ◽  
Emperor Penguins ◽  
The Mean

Heart rate during overnight rest and while diving were recorded from five emperor penguins with a microprocessor-controlled submersible recorder. Heart rate, cardiac output and stroke volume were also measured in two resting emperor penguins using standard electrocardiography and thermodilution measurements. Swim velocities from eight birds were obtained with the submersible recorder. The resting average of the mean heart rates was 72 beats min-1. Diving heart rates were about 15% lower than resting rates. Cardiac outputs of 1.9-2.9 ml kg-1 s-1 and stroke volumes of 1.6-2.7 ml kg-1 were similar to values recorded from mammals of the same body mass. Swim velocities averaged 3 m s-1. The swim speeds and heart rates suggest that muscle O2 depletion must occur frequently: therefore, many dives require a significant energy contribution from anaerobic glycolysis.

Cardiovascular changes in the exercising emu

1983 ◽  
Vol 104 (1) ◽  
pp. 193-201 ◽  
Author(s):  
B. Grubb ◽  
D. D. Jorgensen ◽  
M. Conner
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Oxygen Consumption ◽  
Stroke Volume ◽  
Oxygen Content ◽  
Body Mass ◽  
Fold Increase ◽  
Exercise Heart Rate ◽  
Rate Of Oxygen Consumption ◽  
Cardiovascular Variables

Cardiovascular variables were studied as a function of oxygen consumption in the emu, a large, flightless ratite bird well suited to treadmill exercise. At the highest level of exercise, the birds' rate of oxygen consumption (VO2) was approximately 11.4 times the resting level (4.2 ml kg-1 min-1). Cardiac output was linearly related to VO2, increasing 9.5 ml for each 1 ml increase in oxygen consumption. The increase in cardiac output is similar to that in other birds, but appears to be larger than in mammals. The venous oxygen content dropped during exercise, thus increasing the arteriovenous oxygen content difference. At the highest levels of exercise, heart rate showed a 3.9-fold increase over the resting rate (45.8 beats min-1). The mean resting specific stroke volume was 1.5 ml per kg body mass, which is larger than shown by most mammals. However, birds have larger hearts relative to body mass than do mammals, and stroke volume expressed per gram of heart (0.18 ml g-1) is similar to that for mammals. Stroke volume showed a 1.8-fold increase as a result of exercise in the emus, but a change in heart rate plays a greater role in increasing cardiac output during exercise.

scholarly journals Temperature-dependent development of cardiac activity in unrestrained larvae of the minnow Phoxinus phoxinus

2000 ◽  
Vol 279 (5) ◽  
pp. R1634-R1640 ◽  
Author(s):  
G. Schönweger ◽  
T. Schwerte ◽  
B. Pelster
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Incubation Period ◽  
Body Mass ◽  
Metabolic Activity ◽  
Cardiac Activity ◽  
Swim Bladder ◽  
Phoxinus Phoxinus ◽  
Swim Bladder Inflation

The minnow ( Phoxinus phoxinus) was raised up to the stage of swim bladder inflation at temperatures between 10°C and 25°C, and the time of development significantly decreased at higher temperatures. Accordingly, initiation of cardiac activity was observed at day 2 in 25°C animals and at day 4 in 12.5°C animals. Only a minor increase in body mass was observed during the incubation period, and, at the end of the incubation period, animals raised at 25°C did not have a significantly lower body mass compared with animals raised at 15°C. Metabolic activity, determined as the rate of oxygen consumption of a larva, increased from 3.3 to 19.5 nmol/h during development at 15°C and from 5.6 to 47.6 nmol/h during development at 25°C. Heart rate showed a clear correlation to developmental stage as well as to developmental temperature, but at the onset of cardiac activity, diastolic ventricular volume and also stroke volume were higher at the lower temperatures. Furthermore, stroke volume increased with development, except for the group incubated at 12.5°C, in which stroke volume decreased with development. Initial cardiac output showed no correlation to incubation temperature. Although metabolic activity increased severalfold during development from egg to the stage of swim bladder inflation at 15°C and at 25°C, weight-specific cardiac output increased only by ∼40% with proceeding development. At 12.5°C, cardiac output remained almost constant until opening of the swim bladder. The data support the notion that oxygen transport is not the major function of the circulatory system at this stage of development. The changes in heart rate with temperature appear to be due to the intrinsic properties of the pacemaker; there was no indication for a regulated response.

Use of the cardiopulmonary flow index to evaluate cardiac function in Thoroughbred horses

1991 ◽  
Vol 62 (2) ◽  
pp. 43-47 ◽  
Author(s):  
A. J. Guthrie ◽  
Valerie M. Killeen ◽  
Maria S.G. Mülders ◽  
J. F.W. Grosskopf
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Cardiac Function ◽  
Cardiac Disease ◽  
Clinical Signs ◽  
Simultaneous Recording ◽  
Flow Index ◽  
Heart Rates ◽  
Thoroughbred Horses ◽  
The Mean

The ratio of the cardiopulmonary blood volume to stroke volume is called the cardiopulmonary flow index (CPFI). The CPFI can be determined indirectly from the simultaneous recording of a radio cardiogram and an electrocardiogram. The CPFI and cardiac output were measured simultaneously in horses (n = 10) that were diagnosed as having cardiac disease. The diseased subjects were probably all exposed to feed contaminated with the ionophore, salinomycin, and all showed clinical signs indicative of chronic toxic myocarditis. The results obtained from these subjects were compared with those from control animals and significant differences (P 0,05) were found between the mean CPFI of the control horses and those with macroscopically visible myocardial fibrosis on post mortem examination. No significant differences were found between the means of the cardiac output measured in either of the groups of horses. The effect of pharmacological acceleration of the heart rate on the CPFI was also studied. Significant differences (P 0,05) were found between the mean CPFI and the slopes of the regression lines of CPFI on heart rate of the control and principal groups of horses. These differences were greatest at heart rates near to the resting heart rates of the individuals. The CPFI was found to be a more sensitive measure of cardiac function than cardiac output, in the horses.

Initial hemodynamic responses to mild exercise in trained dogs

1965 ◽  
Vol 20 (3) ◽  
pp. 437-442 ◽  
Author(s):  
Harold Smulyan ◽  
Richard P. Cuddy ◽  
William A. Vincent ◽  
Udomporn Kashemsant ◽  
Robert H. Eich
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Oxygen Consumption ◽  
Stroke Volume ◽  
Right Atrium ◽  
Initial Reaction ◽  
Hemodynamic Responses ◽  
Heart Rates ◽  
Infusion Method ◽  
The Right

The transient changes in cardiac output at the onset of mild exercise were measured in dogs trained to walk on a treadmill. Cardiac output was obtained using a krypton 85 infusion method, which permitted frequent determinations of flow. The first go sec of exercise were marked by a prompt rise and overshoot of heart rate and cardiac output, whereas increases in stroke volume occurred later after the onset of exercise, and to a lesser extent than heart rate. At rest, the right atrium was electrically driven at rates slightly faster than heart rates attained spontaneously with exercise and the studies repeated. Changes in cardiac output with exercise were similar to those in unpaced animals, but when the heart rate was fixed stroke volume increased immediately. These studies show a consistent rise in heart rate and cardiac output in the initial reaction to exercise, but when the prompt rise in heart rate was prevented by pacing from the right atrium, increases in stroke volume provided a comparable response in cardiac output. krypton 85; cardiac output; stroke volume; pacing of heart; oxygen consumption Submitted on September 23, 1964

The Blood Pressure of Giraffes

2021 ◽  
pp. 187-215
Author(s):  
Graham Mitchell
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Cardiac Output ◽  
Hydrostatic Pressure ◽  
Left Ventricle ◽  
Stroke Volume ◽  
Body Mass ◽  
The Brain ◽  
Very High

As discussed in this chapter, giraffes have, compared with any other mammal, a very high mean blood pressure of ~250 mmHg. Human blood pressure is ~90 mmHg. Its size is determined by the length of the neck, the height of the head above the heart, by hydrostatic pressure generated by gravity acting on the column of blood in the carotid artery, and contractions of the heart muscles: blood pressure must be high enough to ensure that blood reaches the brain. Uniquely in giraffes blood pressure is regulated by receptors that are located in both the carotid and occipital arteries. Once thought to be ~2.5% of body mass the heart is smaller (~0.5% of body mass) but its muscle walls, especially of the interventricular wall and left ventricle wall, are exceptionally thick (up to 8 cm). The relative cardiac output is the same as in other mammals (~5 L 100 kg–1 of body mass) through a combination of a higher than predicted heart rate (70 b min–1 vs 50 b min–1) and smaller than predicted stroke volume (~0.7 ml kg–1 body mass vs 1.2 ml kg–1). Stroke volume is small because the left ventricle muscle wall is thick. The origin of high blood pressure is the resistance to blood flow, which is about twice what it is in other mammals. The higher resistance results from a combination of the thick muscular walls and narrow lumens of a giraffe’s blood vessels and unique mechanisms that regulate blood flow to the brain.

Circulation in exercising dogs

1964 ◽  
Vol 19 (1) ◽  
pp. 29-32 ◽  
Author(s):  
P. Cerretelli ◽  
J. Piiper ◽  
F. Mangili ◽  
F. Cuttica ◽  
B. Ricci
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Time Course ◽  
Venous Blood ◽  
Average Maximum ◽  
Blood Pressures ◽  
The Mean ◽  
Maximum Increment ◽  
Measurable Change

The adjustments of the cardiovascular system to muscular exercise were studied in dogs running on a treadmill at different speeds and at the incline of +10%. The cardiac output, measured by the thermodilution method, increased with increasing O2 consumption, reaching 520 ml/kg min at an O2 consumption of 70 ml/kg min. At still higher metabolic levels the cardiac output remained constant and the O2 consumption increased by an increase of the arteriovenous O2 difference only, which was calculated to attain 17 vol % at the highest O2 consumption value reached in this study, 90 ml/kg min. The increase of the cardiac output was mainly due to increase of the heart rate, whereas the average maximum increment of the stroke volume was about 30% only. The mean arterial and the central venous blood pressures increased with exercise. The time course of the adjustment of the cardiac output was measured after the exercise of varied intensity had been abruptly begun or stopped. Both for start and recovery the “half reaction time” was about 20 sec; after 1 min no further measurable change of the cardiac output was detectable. cardiac output and O2 consumption at increasing metabolic levels; heart rate and stroke volume in running dogs recovery following exercise Submitted on July 15, 1963

Physiological factors associated with the lower maximal oxygen consumption of master runners

1989 ◽  
Vol 66 (2) ◽  
pp. 949-954 ◽  
Author(s):  
A. M. Rivera ◽  
A. E. Pels ◽  
S. P. Sady ◽  
M. A. Sady ◽  
E. M. Cullinane ◽  
...  
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Maximal Oxygen Consumption ◽  
Maximal Heart Rate ◽  
Distance Runners ◽  
Physiological Factors ◽  
Factors Associated ◽  
Older Athletes ◽  
Maximal Cardiac Output

We examined the hemodynamic factors associated with the lower maximal O2 consumption (VO2max) in older formerly elite distance runners. Heart rate and VO2 were measured during submaximal and maximal treadmill exercise in 11 master [66 +/- 8 (SD) yr] and 11 young (32 +/- 5 yr) male runners. Cardiac output was determined using acetylene rebreathing at 30, 50, 70, and 85% VO2max. Maximal cardiac output was estimated using submaximal stroke volume and maximal heart rate. VO2max was 36% lower in master runners (45.0 +/- 6.9 vs. 70.4 +/- 8.0 ml.kg-1.min-1, P less than or equal to 0.05), because of both a lower maximal cardiac output (18.2 +/- 3.5 vs. 25.4 +/- 1.7 l.min-1) and arteriovenous O2 difference (16.6 +/- 1.6 vs. 18.7 +/- 1.4 ml O2.100 ml blood-1, P less than or equal to 0.05). Reduced maximal heart rate (154.4 +/- 17.4 vs. 185 +/- 5.8 beats.min-1) and stroke volume (117.1 +/- 16.1 vs. 137.2 +/- 8.7 ml.beat-1) contributed to the lower cardiac output in the older athletes (P less than or equal 0.05). These data indicate that VO2max is lower in master runners because of a diminished capacity to deliver and extract O2 during exercise.

scholarly journals Non-Invasive Scale Measurement of Cardiac Output Compared with the Gold-Standard Direct Fick Method: A Feasibility Study

2021 ◽  
Author(s):  
Daniel Yazdi ◽  
Sarin Patel ◽  
Suriya Sridaran ◽  
Evan Wilson ◽  
Sarah Smith ◽  
...  
Keyword(s):  
Cardiac Output ◽  
Stroke Volume ◽  
Cardiac Function ◽  
Exercise Test ◽  
Gold Standard ◽  
Cardiopulmonary Exercise Test ◽  
Cardiac Monitoring ◽  
Non Invasive ◽  
Cardiopulmonary Exercise ◽  
The Mean

AbstractBackgroundObjective markers of cardiac function are limited in the outpatient setting and may be beneficial for monitoring patients with chronic cardiac conditions.ObjectiveWe assess the accuracy of a scale, with the ability to capture ballistocardiography, electrocardiography, and impedance plethysmography signals from a patient’s feet while standing on the scale, in measuring stroke volume and cardiac output compared to the gold-standard direct Fick method.MethodsThirty-two patients with unexplained dyspnea undergoing level 3 invasive cardiopulmonary exercise test at a tertiary medical center were included in the final analysis. We obtained scale and direct Fick measurements of stroke volume and cardiac output before and immediately after invasive cardiopulmonary exercise test.ResultsStroke volume and cardiac output from a cardiac scale and the direct Fick method correlated with r = 0.81 and r = 0.85, respectively (P < 0.001 each). The mean absolute error of the scale estimated stroke volume was -1.58 mL, with a 95% limits of agreement (LOA) of -21.97 mL to 18.81 mL. The mean error for the scale estimated cardiac output was -0.31 L/min, with a 95% LOA of -2.62 L/min to 2.00 L/min. The change in stroke volume and cardiac output before and after exercise were 78.9% and 96.7% concordant, respectively between the two measuring methods.ConclusionsThis novel scale with cardiac monitoring abilities may allow for non-invasive, longitudinal measures of cardiac function. Using the widely accepted form factor of a bathroom scale, this method of monitoring can be easily integrated into a patient’s lifestyle.

Cardiac Response During Trumpet Playing

2010 ◽  
Vol 25 (1) ◽  
pp. 16-21 ◽  
Author(s):  
Donald U Robertson ◽  
Lynda Federoff ◽  
Keith E Eisensmith
Keyword(s):  
College Students ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Cardiac Output ◽  
Stroke Volume ◽  
Cardiac Response ◽  
Physiological Efficiency ◽  
Rest Periods ◽  
Upper Register

Heart rate, heart rate variability, stroke volume, and cardiac output were measured while six college students and six professionals played trumpet. One-minute rest periods were followed by 1 minute of playing exercises designed to assess the effects of pitch and articulation. Heart rate and heart rate variability increased during playing, but stroke volume decreased. Changes in heart rate between resting and playing were greater for students, although beat-to-beat variability was larger for professionals in the upper register. These results suggest that expertise is characterized by greater physiological efficiency.

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