Parameters to Be Measured during Exercise

2018 ◽  
pp. 82-105
Author(s):  
Gregory S. Thomas ◽  
Myrvin H. Ellestad

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.

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M Bjorkavoll-Bergseth ◽  
B Auestad ◽  
O Kleiven ◽  
O Skadberg ◽  
T Eftestol ◽  
...  

Abstract Background/Introduction Following prolonged strenuous exercise there is an exercise-induced troponin (cTn) elevation in healthy individuals. The precise mechanisms and clinical consequence of this cTn elevation remain to be determined. It has recently been demonstrated that exercise intensity, exceeding a heart rate (HR) of 150 bpm, is correlated with exercise-induced cTn elevation. Purpose The present work aims to determine if there is a threshold for exercise duration with a HR exceeding 150 bpm associated with an excessive exercise-induced cTn elevation. Methods A total of 177 healthy subjects were included in the present analysis of HR data obtained from sport watches used during a 91-km recreational mountain bike cycle race. Clinical status, cTnI, ECGs, blood pressure and demographics were obtained 24 h prior to- and at 3 h and 24 h after the race. Results are reported as median and 25th and 75th percentile. We used Tree regression to determine the association between elevated cTnI and exercise duration exceeding a HR of 150 bpm. Results Subjects were 82% (n=146) males, 44 (39–51) years, with a race time of 3.5 (3.1–3.9) h. Baseline cTnI was 1.9 (1.6–3.3) ng/L. There was a cTnI elevation in all study participants at 3 h, cTnI: 60.0 (36.0–99.3) ng/L, with a significant (p<0.001) reduction at 24 hours following exercise, cTnI: 10.9 (6.1–22.4) ng/L. Tree regression identified 168 min of exercise, with a HR exceeding 150 bpm, to be associated with an excessive increase in cTnI both at 3 h, and at 24 h following the race (figure). The median cTn values above and below the threshold are presented in the Table. Conclusion The present analysis suggests that exceeding a specific duration of high intensity exercise may be associated with excessive cTn elevation in susceptible individuals. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Western Norway Health authoritites.


1985 ◽  
Vol 56 (13) ◽  
pp. 861-862 ◽  
Author(s):  
Massimo Romano ◽  
Teresa Di Maro ◽  
Giovanni Carella ◽  
Maria Rosaria Cotecchia ◽  
Giuseppe Ferro ◽  
...  

1993 ◽  
Vol 75 (2) ◽  
pp. 663-667 ◽  
Author(s):  
M. Saito ◽  
A. Tsukanaka ◽  
D. Yanagihara ◽  
T. Mano

The aim of this study was to clarify the relationship between sympathetic outflow to skeletal muscle and oxygen uptake during dynamic exercise. Muscle sympathetic nerve activity (MSNA) was recorded from the right median nerve microneurographically in eight healthy volunteers during leg cycling at four different intensities in a seated position for a 16-min bout. Work loads selected were 20, 40, 60, and 75% of maximal oxygen uptake (VO2max). Heart rate and blood pressure were measured during each exercise test. MSNA burst frequency was suppressed by 28% during cycling at 20% VO2max (23 vs. 33 bursts/min for control). Thereafter, it increased in a linear fashion with increasing work rate, with a significantly higher burst frequency during 60% VO2max than the control value. Both heart rate and mean blood pressure rose significantly during 20% VO2max from the control value and increased linearly with increased exercise intensity. During light exercise, MSNA was suppressed by arterial and cardiopulmonary baroreceptors as a result of the hemodynamic changes associated with leg muscle pumping. The baroreflex inhibition may overcome the muscle metaboreflex excitation to induce MSNA suppression during light exercise. These results suggest that during light exercise MSNA is inhibited, perhaps due to loading of the cardiopulmonary and arterial baroreflexes, and that during heavier exercise the increase in MSNA occurs as muscle metaboreflexes are activated.


1959 ◽  
Vol 197 (2) ◽  
pp. 437-440 ◽  
Author(s):  
Paul R. Saunders ◽  
Peter B. Taylor

Extracts prepared from the venomous dorsal spines of lionfish ( Pterois volitans) were investigated in mice and rabbits. Intravenous injection into mice produced death in from less than a minute up to about one-half hour. The primary action in rabbits was a fall in blood pressure, accompanied by increase in respiratory rate; with larger doses there was evidence of myocardial ischemia or injury. After injection of fatal doses a variety of electrocardiographic changes occurred and the blood pressure fell to zero; respiratory arrest occurred terminally, but artificial respiration did not prolong the life of the animal. The active material was nondialyzable and the extracts contained considerable amounts of protein. Extracts retained substantial activity after lyophilization or addition of glycerol when stored for over a year at –20°C. The mean ld50 following intravenous injection into mice was about 1 mg of protein/kg.


1996 ◽  
Vol 81 (5) ◽  
pp. 1901-1907 ◽  
Author(s):  
Roland Favier ◽  
Esperanza Caceres ◽  
Laurent Guillon ◽  
Brigitte Sempore ◽  
Michel Sauvain ◽  
...  

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.


1996 ◽  
Vol 85 (4) ◽  
pp. 706-712 ◽  
Author(s):  
Klaus-Dieter Stuhmeier ◽  
Bernd Mainzer ◽  
Jochen Cierpka ◽  
Wilhelm Sandmann ◽  
Jorg Tarnow

Background Most new perioperative myocardial ischemic episodes occur in the absence of hypertension or tachycardia. The ability of alpha 2-adrenoceptor agonists to inhibit central sympathetic outflow may benefit patients with coronary artery disease by increasing the myocardial oxygen supply and -demand ratio. Methods A randomized double-blind study design was used in 297 patients scheduled to have elective vascular surgical procedures to evaluate the effects of 2 micrograms/kg-1 oral clonidine (n = 145) or placebo (n = 152) on the incidence of perioperative myocardial ischemic episodes, myocardial infarction, and cardiac death. Continuous real-time S-T segment trend analysis (lead II and V5) was performed during anesthesia and surgery and correlated with arterial blood pressure and heart rate before and during ischemic events. Dose requirements for vasoactive and antiischemic drugs to control blood pressure and heart rate as well as episodes of myocardial ischemia (i.e., catecholamines, beta-adrenoceptor antagonists, nitrates, and systemic vasodilators) and fluid volume load were recorded. Results Administration of clonidine reduced the incidence of perioperative myocardial ischemic episodes from 39% (59 of 152) to 24% (35 of 145) (P < 0.01). Hemodynamic patterns, percentage of ischemic time, and the number of ischemic episodes per patient did not differ. Nonfatal myocardial infarction developed after operation in four patients receiving placebo compared with none receiving clonidine (day 2 to 21; P = 0.07). The incidence of fatal cardiac events (1 vs. 2) was not different. Dose requirements for vasoactive and antiischemic drugs did not differ between the groups, but the amount of presurgical fluid volume was slightly greater in patients receiving clonidine (951 +/- 388 vs. 867 +/- 381 ml; P < 0.03). Conclusion A small oral dose of clonidine, given prophylactically, can reduce the incidence of perioperative myocardial ischemic episodes without affecting hemodynamic stability in patients with suspected or documented coronary artery disease.


2003 ◽  
Vol 42 (5) ◽  
pp. 688-696 ◽  
Author(s):  
Jean-Paul Vilaine ◽  
Jean-Pierre Bidouard ◽  
Ludovic Lesage ◽  
Hélène Reure ◽  
Jean-Louis Péglion

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Ana Ellen Queiroz Santiago ◽  
Adriana Machado Issy ◽  
Rioko Kimiko Sakata

Objectives. The aim of this study was to assess the effects of clonidine on intraoperative analgesia, sedation, intraocular and blood pressure, arrhythmia, and ischemia.Methods. Forty patients undergoing cataract surgery were allocated into two groups. They were monitored with Holter machine, the pupil was dilated, and 30 minutes later, 20 patients received clonidine (4 µg/kg), while the other 20 patients were given a 0.9% saline intravenously. Twenty minutes later, 2% lidocaine gel was applied. There were assessed intraoperative analgesia, intraocular pressure, blood pressure, heart rate, and the occurrence of arrhythmias and myocardial ischemia.Results. Pain intensity was lower in G1 during the phacoemulsification, irrigation, aspiration, and intraocular lens implantation. The HR and BP were lower with clonidine. The IOP was lower with clonidine after 15 minutes and at the end of the surgery. Sedation was higher with clonidine. The incidence of arrhythmia was lower at the end of surgery with clonidine. The incidence of myocardial ischemia did not differ between the groups.Conclusions. Clonidine (4 µg/kg) before a phacoemulsification reduced the intensity of pain during cataract surgery. It also induced sedation, reduction of BP, HR, and incidence of arrhythmia at the end of the surgery, and did not alter myocardial ischemia. This trial is registered with Clinicaltrials.govNCT01677351.


1965 ◽  
Vol 20 (3) ◽  
pp. 432-436 ◽  
Author(s):  
K. Lange Andersen ◽  
Lars Hermansen

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


2010 ◽  
Vol 298 (3) ◽  
pp. H966-H973 ◽  
Author(s):  
Léna Borbouse ◽  
Gregory M. Dick ◽  
Gregory A. Payne ◽  
Brittany D. Payne ◽  
Mark C. Svendsen ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document