Validity of dynamical analysis to characterize heart rate and oxygen consumption during effort tests

ABSTRACTPerformance is usually assessed by simple indices stemming from cardiac and respiratory data measured during graded exercise test. The goal of this study is to test the interest of using a dynamical analysis of these data. Therefore, two groups of 32 and 14 athletes from two different cohorts performed two different graded exercise testing before and after a period of training or deconditioning. Heart rate (HR) and oxygen consumption (VO2) were measured. The new dynamical indices were the value without effort, the characteristic time and the amplitude (gain) of the HR and VO2 response to the effort. The gain of HR was moderately to strongly associated with other performance indices, while the gain for VO2 increased with training and decreased with deconditioning with an effect size slightly higher than VO2 max. Dynamical analysis performed on the first 2/3 of the effort tests showed similar patterns than the analysis of the entire effort tests, which could be useful to assess individuals who cannot perform full effort tests. In conclusion, the dynamical analysis of HR and VO2 obtained during effort test, especially through the estimation of the gain, provides a good characterization of physical performance, robust to less stringent effort test conditions.

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The complex relationship between effort and heart rate: a hint from dynamical analysis

10.1101/2020.03.01.971929 ◽

2020 ◽

Author(s):

D. Mongin ◽

C. Chabert ◽

A. Uribe-Caparros ◽

J. F. Vico Guzmán ◽

O. Hue ◽

...

Keyword(s):

Heart Rate ◽

Oxygen Consumption ◽

Ventilatory Threshold ◽

The Body ◽

Metabolic Energy ◽

Dynamical Analysis ◽

Performance Curve ◽

Rate Performance ◽

Power Expenditure ◽

Proper Estimation

AbstractHeart rate during effort test has been previously successfully adjusted with a simple first order differential equation with constant coefficients driven by the body power expenditure. Although producing proper estimation and yielding pertinent indices to analyze such measurement, this approach suffers from its inability to model the saturation of the heart rate increase at high power expenditure and the change of heart rate equilibrium after effort. The objective of the present study is to improve this model by considering that the amplitude of the heart rate response to effort (gain) depends on the power expenditure value. Therefore, heart rate and oxygen consumption of 30 amateur athletes were measured while they performed a maximum graded treadmill effort test. The proposed model was able to predict 99% of the measured heart rate variance during exercise. The gains estimated at the different power expenditures were constant but noisy before the first ventilatory threshold, stable and decreasing slightly with power increase between the two ventilatory thresholds, before decreasing in a more pronounced manner after the second ventilatory threshold. The slope of the decrease of heart rate gain with power expenditure was correlated with the deflection angle of the heart rate performance curve and with the maximum oxygen consumption. These results reflect the changes of metabolic energy systems at play during the effort test and are consistent with the analysis of the heart rate performance curve given by the Conconi method, thus validating our new approach to analyze heart rate during effort test.

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CARDIORESPIRATORY SYSTEM UNDER BICYCLE ERGOMETER TEST IN SKIERS WITH DIFFERENT TRAINING STATUS (KOMI REPUBLIC)

Ulyanovsk Medico-biological Journal ◽

10.34014/2227-1848-2019-1-76-84 ◽

2019 ◽

pp. 76-84

Author(s):

Yu.G. Solonin ◽

T.P. Loginova ◽

I.O. Garnov ◽

A.L. Markov ◽

A.A. Chernykh ◽

...

Keyword(s):

Heart Rate ◽

Oxygen Consumption ◽

Komi Republic ◽

Rate Pressure Product ◽

Training Status ◽

Maximum Oxygen Consumption ◽

Bicycle Ergometry ◽

Cardiorespiratory System ◽

Unit Pulse ◽

Ski Racers

The aim of the study is to examine the impact of training status on ski racers (Komi Republic) at rest and under bicycle ergometry evaluating their cardiorespiratory system parameters. Materials and Methods. The authors examined male ski racers with different training status: 22 first-rank sportsmen, 22 candidates for Master of Sports and 22 Masters of Sports. Athletes underwent bicycle ergometry loads up to refusal. Oxycon Pro system (Germany) was used. Then authors studied the complex of cardiorespiratory parameters, calculating maximum oxygen consumption and unit physiological cost. Results. At rest and under standard physical load (200 W) Masters of Sports demonstrate significantly increased training status among ski racers in such cardiorespiratory system parameters as heart rate, rate pressure product and oxygen pulse. Under standard physical load (200 W) statistically significant differences between first-rank sportsmen and candidates for Master of Sports are detected by heart rate, rate pressure product, respiration rate, respiratory minute volume and oxygen utilization coefficient. Such deviations indicate differences in training status. Under maximum load, the highest training status is found in Masters of Sports: bicycle ergometry load power and duration; unit pulse, pressor and cardiac cost, bulk and unit values of maximum oxygen consumption. Heart rate values, unit pulse and heart-vent cost indicate a high training status in candidates for Master of Sports under load up to refusal, if compared with first-rank sportsmen. Athletes’ organism under load up to refusal works more efficiently than under moderate load (200 W). The training status in ski racers (Komi Republic) is manifested in the saving cardiorespiratory system functions, both at rest and under standard bicycle ergometry, as well as in parameters of unit physiological cost under loads up to refusal and increased values of maximum oxygen consumption. Keywords: ski racers, Komi Republic, training status, bicycle ergometry loads, cardiorespiratory system, maximum oxygen consumption.

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Oxygen Consumption, Heart Rate, and Blood Lactate Responses to an Acute Bout of Plyometric Depth Jumps in College-Aged Men and Women

The Journal of Strength and Conditioning Research ◽

10.1519/jsc.0b013e3181b22b63 ◽

2010 ◽

Vol 24 (9) ◽

pp. 2475-2482 ◽

Cited By ~ 15

Author(s):

Gregory A Brown ◽

Michael W Ray ◽

Bryce M Abbey ◽

Brandon S Shaw ◽

Ina Shaw

Keyword(s):

Heart Rate ◽

Oxygen Consumption ◽

Blood Lactate ◽

Acute Bout ◽

Men And Women

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Accuracy of the Heart Rate Index Equation to Assess Oxygen Consumption in Obese Patients

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000493687.24029.2b ◽

2014 ◽

Vol 46 ◽

pp. 169-170

Author(s):

Roger L. Sacks ◽

Barry Franklin ◽

Judy Boura ◽

James Van Loon

Keyword(s):

Heart Rate ◽

Oxygen Consumption ◽

Obese Patients

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alpha-Adrenergic control of oxygen delivery to myocardium during exercise in conscious dogs

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1982.242.5.h805 ◽

1982 ◽

Vol 242 (5) ◽

pp. H805-H809 ◽

Cited By ~ 17

Author(s):

G. R. Heyndrickx ◽

P. Muylaert ◽

J. L. Pannier

Keyword(s):

Heart Rate ◽

Blood Flow ◽

Oxygen Consumption ◽

Coronary Blood Flow ◽

Coronary Sinus ◽

Oxygen Delivery ◽

Left Ventricular ◽

Conscious Dogs ◽

Adrenergic Blockade ◽

Adrenergic Control

alpha-Adrenergic control of the oxygen delivery to the myocardium during exercise was investigated in eight conscious dogs instrumented for chronic measurements of coronary blood flow, left ventricular (LV) pressure, aortic blood pressure, and heart rate and sampling of arterial and coronary sinus blood. After alpha-adrenergic receptor blockade a standard exercise load elicited a significantly greater increase in heart rate, rate of change of LV pressure (LV dP/dt), LV dP/dt/P, and coronary blood flow than was elicited in the unblocked state. In contrast to the response pattern during control exercise, there was no significant change in coronary sinus oxygen tension (PO2), myocardial arteriovenous oxygen difference, and myocardial oxygen delivery-to-oxygen consumption ratio. It is concluded that the normal relationship between myocardial oxygen supply and oxygen demand is modified during exercise after alpha-adrenergic blockade, whereby oxygen delivery is better matched to oxygen consumption. These results indicate that the increase in coronary blood flow and oxygen delivery to the myocardium during normal exercise is limited by alpha-adrenergic vasoconstriction.

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Respiratory Metabolism During Pregnancy in the Guinea Pig

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1957.190.3.425 ◽

1957 ◽

Vol 190 (3) ◽

pp. 425-428 ◽

Cited By ~ 2

Author(s):

Richard M. Hoar ◽

William C. Young

Keyword(s):

Heart Rate ◽

Oxygen Consumption ◽

Guinea Pig ◽

Metabolic Rate ◽

Adrenal Cortex ◽

Guinea Pigs ◽

Sharp Decrease ◽

Zona Fasciculata ◽

Respiratory Metabolism ◽

Morphological Differences

Oxygen consumption and heart rate during pregnancy were measured in untreated, thyroxin-injected and thyroidectomized guinea pigs given I131. From impregnation until parturition, oxygen consumption increased 7.9% in untreated females. The increase continued until 5 days postpartum when a sharp decrease occurred. The increase is not accounted for by growth of the fetal mass. Comparable increases occurred in thyroxin-injected (16.2%) and thyroidectomized (11.9%) females, although the levels throughout were higher and lower, respectively, than in intact females. Heart rate did not increase. On the contrary, statistically significant decreases occurred in the untreated and thyroxin-injected females. Although the mechanism associated with the increased metabolic rate is not known, the possibility of thyroid participation would seem to be excluded. Involvement of the adrenal cortex is suggested by morphological differences in the cells of the zona fasciculata in pregnant and nonpregnant females and by evidence cited from other studies.

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