Physiological correlates of schedule-induced activities in rats

Oxygen consumption and heart rate as well as a range of behavior variables were tracked continuously as rats adapted to a schedule of food delivery. Over 15 days of observation a majority of the subjects developed characteristic patterns of schedule-induced polydipsia (SIP) in which bouts of drinking reliably followed food delivery. Variations in food tray entries, oxygen consumption, heart rate, and, in the final stage of the experiment, rates of general activity were also time locked to food delivery in both rats exhibiting SIP and nondrinkers. However, the patterns of variation in these measures differed consistently between these two groups. Oxygen consumption varied over a wider range and reached higher levels in drinkers than nondrinkers. Additionally, heart rate was lower in the drinkers, which, in the final stage of the experiment, also exhibited depressed rates of food tray entries and general activity relative to the nondrinkers. Each of these between-subject differences was paralleled by differences within the drinking group between trials on which drinking occurred and trials on which it did not occur. The implications of these results on the utility of unidimensional energetic constructs are discussed.

Download Full-text

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.

Download Full-text

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

Download Full-text

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

Download Full-text

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.

Download Full-text

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.

Download Full-text