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The bicycle ergometric test was used to examine exercise tolerance in 73 patients with coronary heart disease following a single remedial plasmapheresis session, which removed an average of 1562.2 ml plasma. A rapid increase in exercise tolerance was significantly revealed in patients with Functional Class IV exertional angina.
Vascular headaches may occur in up to 20% of the population aged 17-40. One subgroup, exertional headaches, has many specific and nonspecific clinical presentations. Knowing the background events preceding the headache and the exact circumstances of the headache can help make a specific diagnosis. Three cases are presented to illustrate the diversity of triggers and their effect on aeromedical decision-making. The headaches are presented within the recently revised nomenclature for head and facial pain by the Headache Classification Committee of the International Headache Society.
A study of 59 patients of stable exertion stenocardia (functional class III) revealed an increased content of lipid hydroperoxide in lipoproteids of low and very low density that was associated with an increased level of malonic dialdehyde in of their functional activity, in particular, during physical loads. Finoptin monotherapy did not effect essentially the level of hydroperoxides in lipoproteids of low density, malonic dialdehyde in thrombocytes. Combination of finoptin and alpha-tocopherol reduced essentially the processes of lipid peroxidation, reducing, thus, the functional activity of thrombocytes at rest and loads.
Determination of the intensity and duration of physical activity with respect to the individual condition of the organism is essential for the effective control of physical training. One of the possible methods of establishing those quantities is making use of the dependence of intensity on the duration of physical exercise. Using semi-logarithmic coordinates (the intensity of exercise is given in the decomal system, the period of time in logarithms) this dependence is of the linear type. The straight line constructed from the limit (highest) intensities of exertion and the relevant times of exercise in any given individual, which must take into account that individual's state of health and fitness, cuts the plane of all conceivable combination of intensity-duration, into two semi-planes. All the actual combinations of those variables exploitable for training purposes are found in the semi-plane situated to the left of this line. With regard to the purpose of physical training it is then possible simply to choose the required intensity of exercise and to find the respective zone of the duration of this exercise, or it is possible to choose the duration of physical exercise and to read from the graph the respective zone of intensity. This intensity can be put either in terms of the speed of movement or, indirectly, in terms of the heart rate. This method of determining the intensity and duration of physical exercise can be used for all activities of the cyclic type, e.g. running, cycling, swimming and so on.
Exertional heatstroke (EH) occurs when heat production, generated by muscular exercise, exceeds the body's heat dissipation capacities. This illness has been reported among young, active individuals, laborers, and religious pilgrims. Although EH includes a rectal temperature above 39.5 degrees C (depending on the timing of the measurement) and elevation of serum enzymes, altered mental status is the universally accepted sign which distinguishes EH from heat exhaustion. Once EH is suspected, cooling therapy should be initiated immediately and investigation of multiple-system involvement should be undertaken. Delay in diagnosis occurs more commonly in moderate environments, when suspicion of EH is low. Complications of EH include the central nervous, cardiovascular, pulmonary, and gastrointestinal systems, often with renal and hematologic involvement. Treatment at the point of collapse should focus on clearing the airway, measurement of rectal temperature, whole body cooling, intravenous therapy, and prompt evacuation. Hospital treatment should emphasize whole body cooling, control of convulsions, monitoring of acid-base status, cardiac function, and renal function. The incidence of EH has been reduced markedly in Israel, by using the following simple guidelines: rest periods during exercise in heat, medical monitoring of strenuous activities, use of meteorological indices, and evaluation of medical history.
The purpose of this study was to analyse characteristic of myocardial infractions that occur during, or immediately after sport-related exertion in subjects who are neither athletes nor professional sportsmen and who undergo coronary angiography. Ten cases where myocardial infraction developed during (n = 3) or immediately after (n = 7) a game were studied retrospectively. All patients were men aged from 21 to 61 years (mean 48.8 years); 8 of them were smokers and 5 had hypercholesterolaemia. The sports practised were tennis (3), cycling (2), football (2), skiing (2) and weight-lifting (1). The infarction was inferior or basal in 5 cases, lateral in 1 case and anterior or anteroseptal in 4 cases. Coronary lesions involved one vessel in 6 and two vessels in 2 patients aged from 47 to 61 years. They were absent in 2 patients aged 24 and 26 respectively, with methylergonovine-induced spasm in one case. The outcome over a 2.9 years follow-up period was favorable, except for one death 6 months after the infarction (patient aged 24, normal coronary arteries, spasm). The outstanding features in this study are: (1) the occurrence of infraction during the recovery period and the noxious role played by smoking; (2) the contrast between the presence of atherosclerotic coronary lesions in middle age subjects and their absence in younger subjects (infarction due to spasm or thrombosis?), and (3) the possible usefulness of an exercise test in sport players of more than 40 years of age.
Needle biopsies from m. gluteus medius of 22 horses which had suffered from repeated attacks of exertional myopathy were studied at various times after an attack, to determine if metabolic alterations can be demonstrated by enzyme histochemistry. Morphological changes and activity of 25 enzymes were studied. Immediately after onset of an attack, some large rounded fibres with a defect of the oxidative phosphorylation were seen. After some hours these fibres lost their glycolytic enzyme activity, followed by disappearance of mitochondrial enzyme activity with accumulation of Ca2+-containing substances. After 16 h inflammatory cells were found in and around necrotic fibres with a strong activity of acid phosphatase and of the 2 oxidative enzymes of the pentose phosphate pathway. The 4th d after onset of the myopathy regenerating fibres could be observed with a strong activity of both NADPH-producing enzymes of the pentose phosphate pathway. The activity of the decarboxylating enzymes NADP+-malate dehydrogenase and NADP+-isocitrate dehydrogenase was increased in these fibres as well. After some month the studied skeletal muscles were completely normal again. Metabolic interpretations based on the histochemical findings are discussed and compared with those given in literature.
This study evaluated the effects of excess body fat on fine motor performance prior to and following moderate and heavy intensities of physical exertion. An attempt was made to demonstrate a reduction in psychomotor performance, postexercise, among obese non-fit subjects who might be seen as occupationally unsuitable for certain military or civilian operational roles. One hundred healthy males (mean age +/- S.D. = 29.1 +/- 6.0 years) volunteered for the study. Motor performance was assessed using the Canadian National Research Council tracometer, a device which integrates choice reaction time and pursuit tracking on a step-input subject-paced pursuit tracking task. These measurements were taken prior to and following moderate and heavy treadmill exercise (at 6 METs and 9 METs, which produced (mean +/- S.D.) heart rates of 130 +/- 15 bpm and 173 +/- 17 bpm, respectively). When the subjects were classified according to % body fat (desirable less than or equal to 14.9%; overfat 15-24.9%; obese greater than or equal to 25%), there were no significant differences in postexercise motor performance among these groups. For all groups, the moderate exercise had no effect on tracometer performance, while heavy exercise led to an immediate deterioration in performance followed by a slight improvement. In this particular experimental protocol, postexercise fine motor performance was not significantly influenced by excess body fat.
A case of exertion-induced heatstroke which illustrates the multiple complications of hyperthermia, including jaundice, coagulopathy and cardiac abnormalities, is reported. The need to increase public awareness of the danger of hyperthermia, and of preventive and first-aid measures, is emphasized.
The purpose of this study was to investigate the effects of state of training and gender on ratings of perceived exertion (RPE) at the lactate threshold (LT), and to determine whether RPE during moderate to heavy sub-maximal exercise is more closely associated with LT or %VO2max. RPE at the LT (RPELT) and at various percentages of VO2max were compared in 10 male and 10 female trained distance runners, and 10 male and 10 female untrained subjects, 18 to 35 yr of age. Mean (+/- SD) VO2max [ml X kg FFW-1 (fat-free weight) X min-1] of the trained men and women (72.3 +/- 1.4 and 73.1 +/- 1.6) was significantly higher (P less than 0.05) than for the untrained men and women (60.2 +/- 1.4 and 53.2 +/- 1.8), confirming their higher cardiorespiratory capacity. Similarly, the mean LTs (%VO2max) of the trained men and women (79.2 +/- 1.7% and 73.3 +/- 1.8%) were significantly higher (P less than 0.05) than for the untrained men and women (66.5 +/- 3.3% and 58.9 +/- 3.3%), and mean values for the men were significantly higher (P less than 0.05) than for the women. The means for RPELT for the four groups, 13.6 +/- 2.1, 13.5 +/- 1.6, 13.5 +/- 1.5, and 12.9 +/- 1.3, respectively, were not significantly different (P greater than 0.05), even though the ratings were given at markedly different levels of VE, VO2 (1 X min-1), heart rate, and %VO2max.(ABSTRACT TRUNCATED AT 250 WORDS)
Preexercise, exercise, and postexercise pressure measurements were performed simultaneously in the tibialis posterior muscle and the deep posterior compartment, to establish a diagnosis of exertional tibialis posterior compartment syndrome. The tibialis posterior muscle occupies its own fascial compartment and therefore should be decompressed at the time of deep posterior compartment fasciotomy.
In amyotrophic lateral sclerosis (ALS), respiratory problems are usually late complications. However, ALS may occasionally present with exertional dyspnea as the primary symptom, as was the case in the patient reported here. On the basis of this case and the literature, the diagnostic and therapeutic aspects of the neurologic causes of dyspnea are discussed. Where there is a discrepancy between severity of blood gas alterations, changes in lung volume determinations and severity of dyspnea, a neuromuscular disorder must be considered in differential diagnosis.
The response of the cardiovascular system to muscular exertion whether dynamic or static, depends on several factors, such as sex, age, position, level of training, etc. If some physiological responses of the heart are well known, others remain debatable, especially the behavior of the telediastolic volume of the left ventricle. The ejection fraction of this ventricle is increased, essentially by improvement of the myocardial contractility. In ischemic cardiopathies, the behavior of the hemodynamic variables is more disputed than in the normal patient, and of course, depends before all on the area of the ischemic zone: the total performance of the heart depends on the interactions between zones which are little or not contractile and normal zones. Physical training could, in addition to its peripheral action have an action on the myocardial function on coronary patients.
Ten male subjects underwent exercise testing in three modes, arms (A), legs (L), and arms + legs (A + L), after ingesting 0.3 g X kg-1 body weight of either NaHCO3 to induce alkalosis or CaCO3 as a placebo (i.e., six exercise trials). Ratings of perceived exertion (RPE: Borg, 15-pt scale) for the arms (RPE-A), legs (RPE-L), chest (REP-C), and overall body (RPE-O) did not differ between acid-base conditions at 20, 40, or 60% VO2max for all three exercise modes. At 80% VO2max, 1) RPE-A was lower (P less than 0.01) during A; 2) RPE-L was lower (P less than 0.01) during L; and 3) RPE-A and RPE-L were lower (P less than 0.01) during A + L under the NaHCO3 as compared to the CaCO3 condition. Differences were not found for RPE-L during A or for RPE-A during L. RPE-C and RPE-O were lower (P less than 0.01) under NaHCO3 during A, L, and A + L. Blood acid-base, VO2, and cardiorespiratory responses were not differentially influenced by exercise mode. Blood pH was significantly higher under NaHCO3 than CaCO3 at pre-exercise and 80% VO2max. VO2, heart rate, and tidal volume did not differ between acid-base conditions at any exercise intensity. VE and respiratory rate did not differ between acid-base conditions at 20, 40, or 60% VO2max but were significantly lower under NaHCO3 at 80% VO2max. RPE-A and L were positively related to blood [H+], and RPE-C was positively related to VE for all exercise modes.
Platelet activation, with the subsequent generation of Thromboxane (Tx) A2, has been implied as a possible cause of resting as well as exercise induced myocardial ischemia. To verify the latter hypothesis, we measured the exercise release of TxB2, the stable metabolite of TxA2, in 9 patients with exertional angina and left anterior descending coronary artery disease. Three of the patients also suffered from angina at rest, due to coronary vasospasm. The great cardiac vein flow, venous efflux from the myocardial territory supplied by the left anterior descending, was determined by the thermodilution technique in the basal conditions, at peak exercise when angina and/or significant ST changes occurred, and 20 min after exercise. Simultaneous blood samples were drawn from the great cardiac vein and a peripheral artery for TxB2 measurements. Regional coronary resistances were calculated as the ratio of mean arterial pressure and coronary flow. At peak exercise the great cardiac vein flow increased and regional coronary resistances decreased in all patients, except in one who showed exercise induced coronary spasm. An increase in TxB2 release was found in 3 patients, a decrease in 3, while the remaining 3 patients did not show significant changes. After exercise the great cardiac vein flow and regional coronary resistances returned to control values in all, whereas both great cardiac vein and arterial TxB2 levels were increased in 6 patients. Our data show that no apparent relation exists between exercise-induced changes in coronary resistances and generation of TxB2.(ABSTRACT TRUNCATED AT 250 WORDS)
Every energy demanding process in the skeletal muscle is associated with the use of adenosinetriphosphate, the essential muscular high-energy phosphate. ATP is rephosphorylated by ADP (= adenosine diphosphate) and this process depends on the type, intensity and duration of the physical exercise. At the beginning of a vigorous physical exercise utilization of intramuscular ATP and phosphocreatine is predominant (= anaerobic-alactacide energy yielding). Then the ATP rephosphorylation based on the conversion of glycogen and glucose to lactate, especially by an exercise duration till 2 min (= anaerobic-alactacide energy yielding). Toward this duration or if the exertion intensity at start has been below 60 to 70% of maximal physical performance, ADP is rephosphorylated during oxidative phosphorylation by the skeletal muscle mitochondria using glycogen, glucose or free fatty acids as energy fuel. Training, age and sex may influence anaerobic and aerobic energy-yielding as well as metabolism and ultrastructure of skeletal muscle.
It is widely accepted that the occurrence of chest pain and/or ST segment elevation during ergonovine testing is a hallmark of abnormal coronary constriction. However, the negativity of this test cannot be considered as an incontrovertible proof of the absence of coronary sensitivity to vasoconstriction. Indeed, it could only indicate that the resulting effect is inadequate to critically reduce coronary blood flow. To test this hypothesis we studied 12 patients with proven coronary artery disease and negative ergonovine test who had complained of chronic exertional angina pectoris and referred variable threshold for the occurrence of pain. They were submitted to atrial pacing (starting from 90 bpm, with 10 bpm increments every 2 min) before (control) and after ergonovine administration (total dose = 0.675 mg). Time, heart rate and rate pressure product were evaluated at the onset of angina and significant ischemia (0.1 mV ST segment depression). After ergonovine, angina was achieved earlier (405 +/- 173 vs 526 +/- 180 sec, p less than 0.005) than during control and at a lower heart rate (116 +/- 15 vs 131 +/- 15 bpm, p less than 0.001) and rate pressure product (15.8 +/- 2.0 vs 18.8 +/- 2.3 X 10(3) U, p less than 0.001). Changes in anginal threshold were widely variable among cases being that the time to onset of pain was dramatically reduced in certain patients but unchanged in one. Similar results were obtained when substituting the ischemic to the anginal threshold. Thus, negativity to ergonovine testing does not imply the absence of coronary constriction which may be revealed when increasing myocardial oxygen demand by atrial pacing.(ABSTRACT TRUNCATED AT 250 WORDS)
In 10 healthy subjects the injection of 10-methyl-1,6-diemthyl-ergoline-8 beta-methanol-(5-bromonicotinate (nicergoline, Sermion) (5 mg i.v.) caused a permanent decrease in blood pressure. This decrease in blood pressure is due to a rapidly occurring alpha-blocking effect and a secondary central alpha-stimulating effect which did not affect the postural regulating mechanisms of the arterial blood pressure in their function. The bradycardia and the elevation of the systolic volume and of the cardiac output are based on this central effect. After oral administration of 30 mg nicergoline the same modifications appeared but to a lesser extent. If nicergoline was administered in a dosage of 30 mg p.o. 1 h before bicyle exercise (100 W for 5 min), the cardiac output and blood flow in the lower extremities increased and the elevation of the systolic pressure was limited. However, the reactive tachycardia remained at the same level. The metabolic consequences of this administration resulted in an inhibited increase in the concentration of lactic acid in the blood, which is normally caused by this exertion. This favourable metabolic effect can be explained by 1. the initial bradycardia and the decrease in the total peripheral resistance whereby the oxygen consumption of the myocardium is reduced; 2. the peripheral vasodilation.