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Results 601 - 650 of 816
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Gottlieb M - - 1989
Muscle fibre recruitment was investigated during draught loaded exercise by studying glycogen depletion patterns from histochemical stains of muscle biopsies from the gluteus and semitendinosus muscles. Three Standardbred trotters performed several intervals of draught loaded exercise on a treadmill with 34 kp at a trot (7 m/sec) and with 34 ...
Sarova-Pinhas I - - 1989
McArdle disease is reported in three generations of a consanguineous Druze family. The diagnosis was established on the basis of a failure of a rise in lactate in the ischemic forearm exercise test, glycogen accumulation in muscle fibers and the lack of myophosphorylase by histochemical and biochemical studies. The inheritance ...
Richter E A - - 1989
The effect of 1 h of dynamic one-legged exercise on insulin action in human muscle was studied in 6 healthy young men. Four hours after one-legged knee extensions, a three-step sequential euglycemic hyperinsulinemic clamp combined with arterial and bilateral femoral vein catheterization was performed. Increased insulin action on glucose uptake ...
Green H J - - 1989
This study examined the question of whether increases in plasma volume (hypervolemia) induced through exercise affect muscle substrate utilization and muscle bioenergetics during prolonged heavy effort. Six untrained males (19-24 yr) were studied before and after 3 consecutive days of cycling (2 h/day at 65% of peak O2 consumption) performed ...
Reed M J - - 1989
The primary purpose of this study was to determine whether gastric emptying limits the rate of muscle glycogen storage during the initial 4 h after exercise when a carbohydrate supplement is provided. A secondary purpose was to determine whether liquid (L) and solid (S) carbohydrate (CHO) feedings result in different ...
Adams J H - - 1989
Liver and muscle glycogen, and blood 3-hydroxybutyrate concentrations were studied during and for 2 h after treadmill running for 1 h, in 144 carbohydrate-starved trained and untrained rats. The resting liver glycogen concentration of the trained animals was 227 +/- 8 (mean +/- S.E.M.) mumol glucosyl units/g wet mass, compared ...
Green H J - - 1989
To investigate the metabolic basis for the reduction in peak blood lactate concentration that occurs with maximal exercise after acclimatization to altitude, eight male subjects [maximal O2 uptake of 51.2 +/- 3.0 (SE) ml.kg-1.min-1] were acclimated to progressive hypobaria over a 40-day period. Before decompression (SL-1), at 380 and 282 ...
Adams J H - - 1989
Post-exercise ketosis is known to be suppressed by physical training and by a high carbohydrate diet. As a result it has often been presumed, but not proven, that the development of post-exercise ketosis is closely related to the glycogen content of the liver. We therefore studied the effect of 1 ...
Hall N A - - 1989
The ceroid-lipofuscinoses (CL) are a group of inherited diseases characterised by the accumulation, in brain, of autofluorescent storage cytosomes which have similar histochemical staining properties to lipofuscin, the neuronal wear and tear pigment of old-age brain. The storage cytosomes stain strongly with periodic acid-Schiff reagent (PAS), indicating the presence of ...
Vissing J - - 1989
The influence of supranormal compared with normal hepatic glycogen levels on hepatic glucose production (Ra) during exercise was investigated in chronically catheterized rats. Supranormal hepatic glycogen levels were obtained by a 24-h fast-24-h refeeding regimen. During treadmill running for 35 min at a speed of 21 m/min, Ra and plasma ...
Hargreaves M - - 1988
Muscle-glycogen breakdown during exercise is influenced by both local and systemic factors. Contractions per se increase glycogenolysis via a calcium-induced, transient increase in the activity of phosphorylase a, and probably also via increased concentrations of Pi. In fast-twitch muscle, increases in the AMP and IMP levels may increase phosphorylase activity. ...
Adams J H - - 1988
1. Experiments were carried out to establish what relationship there is between the concentration of ketone bodies in the blood and the concentrations of glycogen in muscle and liver of thirty-six trained and thirty-six untrained rats exercised at the same absolute load. There were, in addition, non-exercised control animals (of ...
Ivy J L - - 1988
The purpose of this study was to determine whether the rate of muscle glycogen storage could be enhanced during the initial 4-h period postexercise by substantially increasing the amount of the carbohydrate consumed. Eight subjects cycled for 2 h on three separate occasions to deplete their muscle glycogen stores. Immediately ...
Martineau L - - 1988
The purpose of the present study was to clarify the importance of skeletal muscle glycogen as a fuel for shivering thermogenesis in humans during cold-water immersion. Fourteen seminude subjects were immersed to the shoulders in 18 degrees C water for 90 min or until rectal temperature (Tre) decreased to 35.5 ...
Trudeau F - - 1988
The purpose of this study was to further document the role of locally released norepinephrine (NE) in the control of metabolic and endocrine responses to exercise in rats. Post-ganglionic blockade with bretylium (20 mg.kg-1, i.v.) reduced NE release from sympathetic nerve endings and triggered a compensatory increase in epinephrine (E) ...
Gillard D - - 1988
A validation study was conducted of a gas chromatographic procedure for the determination of pentachlorophenol (PCP) in chicken, pork, and beef liver. Five analysts representing 5 laboratories analyzed randomly numbered blind duplicates at 3 fortified tissue concentrations and one incurred tissue on 2 consecutive days. The PCP concentrations ranged from ...
Bye A M - - 1988
A 13-year old boy presented with a 10-year history of severe muscle cramps experienced an hour after prolonged exercise. There was no history of exercise intolerance or myoglobinuria. A muscle biopsy showed a lipid myopathy and a deficiency of muscle carnitine palmityl transferase. He has responded to a high carbohydrate, ...
Kaciuba-Uściłko H - - 1988
Muscle glycogen, glycolytic intermediate and high energy phosphate contents were compared in 5 intact-control (C) and thyroidectomized (THY) dogs after 30 min treadmill exercise of low (40W) and high (70W) intensities. Although after the exercise of relatively low intensity the rate of glycogenolysis and muscle lactate accumulation in THY dogs ...
Allenberg K - - 1988
The effects of obesity, weight reduction, and physical condition on the concentrations of glucose-6-phosphate (G-6-P) and glycogen, and the activities of glycogen synthase (GS) and lactate dehydrogenase (LD) were determined in resting vastus or gastrocnemius muscles of 40 healthy subjects. In obese women the activity of GS was 50% (P ...
Manore M M - - 1988
Pyridoxal 5'-phosphate is an essential co-factor for glycogen phosphorylase and certain enzymes in the alanine-glucose cycle. Glycogen phosphorylase is also proposed as a storage reservoir for vitamin B6. To examine the effect of vitamin B6 and carbohydrate on fuel substrates during exercise, 5 young/trained, 5 young/un-trained, and 5 post-menopausal/un-trained women ...
Norman B - - 1988
To study the relationship between glycogen depletion and IMP accumulation in different fibre types, single fibres were dissected from biopsies taken at rest and after one hour of exercise at 70% of maximal oxygen uptake. These fibres were analysed histochemically for glycogen and fibre types and pooled into classes of ...
Johnson J L - - 1988
To determine whether prior exercise affects the pathways of liver and muscle glycogen synthesis, rested and postexercised rats fasted for 24 h were infused with glucose (200 mumol.min-1.kg-1 iv) containing [6-3H]glucose. Hyperglycemia was exaggerated in postexercised rats, but blood lactate levels were lower than in nonexercised rats. The percent of ...
Lavoie J M - - 1988
Metabolic effects of a selective hepatic vagotomy (HV) were investigated in nonfasted (N) and 24-h fasted (F) rats, at rest and immediately after a 50-min exercise period (26 m/min, 0% grade). In nonfasted rats, no significant differences between HV and sham-operated (SHM) groups were found in blood substrates [free fatty ...
Ivy J L - - 1988
The time of ingestion of a carbohydrate supplement on muscle glycogen storage postexercise was examined. Twelve male cyclists exercised continuously for 70 min on a cycle ergometer at 68% VO2max, interrupted by six 2-min intervals at 88% VO2max, on two separate occasions. A 25% carbohydrate solution (2 g/kg body wt) ...
Gorostiaga E M - - 1988
This study was undertaken to determine the effects of increased substrate availability (glycogen + plasma fatty acids) by glucocorticoids on energy metabolism during exercise to exhaustion. Female rats received a single subcutaneous injection of cortisol acetate (CA) (100 mg.kg body wt-1) 21 h before treadmill running (30.8 m/min). At the ...
Parkhouse W S - - 1988
The purpose of this investigation was to examine the fuels supporting high-intensity progressive exercise and their regulation within rainbow trout. During the sustained swim, red muscle (RM) used 97% (17.5 mumol/g) of its glycogen, whereas white muscle (WM) glycogen only declined 31% (7.3 mumol/g). During the burst swim, WM glycogen ...
Bracken M E - - 1988
To determine the effects of cocaine on exercise endurance, male rats were injected intraperitoneally with cocaine (20 mg/kg body wt) or saline and then run to exhaustion 20 min later at 22 m/min and 15% grade. Saline-injected animals ran 74.9 +/- 16.5 (SD) min, whereas cocaine-treated rats ran only 29 ...
Cartee G D - - 1988
Glycogen utilization during exercise appears to be related to muscle respiratory capacity. Since the decline in hindlimb muscle respiratory capacity that occurs in rats during old age is eliminated when young and old rats undergo an identical exercise training protocol, liver and gastrocnemius glycogen concentrations were determined in identically trained ...
Auclair E - - 1988
The purpose of this study was to test the hypothesis that oral ingestion of lipids could increase endurance by slowing the rate of glycogen depletion. Trained rats were killed after a 2 h run on a rodent treadmill, following an intragastric infusion of water, glucose, medium chain triglycerides (MCT) or ...
Namiot Z - - 1988
The effect of prolonged exercise on the glycogen level in the respiratory muscles (diaphragm--D, external intercostal--IE and internal--II) has been studied in four groups of rats: 1-control, 2-fasted for 24 h, 3-treated with nicotinic acid and 4-treated with propranolol. There was a sharp reduction in glycogen level in each muscle ...
Oyono-Enguelle S - - 1988
Changes in the main physiological parameters and circulating indicators of carbohydrate, protein, lipid (and ketone body) metabolism were measured in ten exercising subjects before L-carnitine (L-carn) loading, after 4 weeks of daily loading with 2 g L-carn, and 6-8 weeks after terminating L-carn administration. Measurements were made on venous blood ...
Hartl W H - - 1988
To evaluate changes of peripheral ketone body (KB) metabolism after operation, muscle metabolism in postsurgical patients was studied at 3 hours (SI) and 24 hours (SII) after surgery by the forearm catheter technique. Data were compared to those of equivalent fasted controls (CI, CII). In a manner consistent with enhanced ...
Kuipers H - - 1987
In 7 male cyclists glycogen synthesis during exercise and rest was studied. Each subject did two exercise trials (A and B), in random order. In both trials, after determining the maximal workload (Wmax), intermittent exercise was given to exhaustion. After the exhaustive exercise and taking a muscle biopsy the subjects ...
Norman B - - 1987
To study changes in muscle energy state during prolonged exercise, especially in relation to fatigue, muscle biopsies were obtained from seven healthy males working until exhaustion on a cycle ergometer at 68% (63-74%) of their maximal oxygen uptake. Biopsies were taken at rest, after 15 and 45 min of exercise ...
Blomstrand E - - 1987
Six male subjects performed intensive cycle exercise to exhaustion after cooling their legs in water at 10-12 degrees C (muscle temperature (Tm) 28 +/- 2.6 degrees C, mean +/- SD). Exercise at exactly the same rate and duration (370 +/- 34 W, 1.5 +/- 0.2 min) was then repeated by ...
Erickson M A - - 1987
Five competitive cyclists were used to determine the effects of fluid intake (16 ml.kg-1) consisting of: (i) non-nutrient control (CON); (ii) fructose (1 g.kg-1) before exercise (FRU); (iii) caffeine (5 mg.kg-1) before exercise (CAF); (iv) glucose (1 g.kg-1) during exercise (GLU); and (v) fructose/caffeine before and glucose during exercise (CFG) ...
Nieman D C - - 1987
Nine male marathon runners were exercised to exhaustion to determine the effects of a 27-h fast on endurance performance. Each subject completed two exercise tests at the same treadmill speed (set at 70% maximal O2 uptake), one following a 27-h fast and one 3 h after a preexercise meal, in ...
Favier R J - - 1987
The importance of gluconeogenic substrates (i.e., lactate, glycerol, and alanine) in the glycogen resynthesis observed in fasting rats after exhausting submaximal exercise [R.D. Fell et al. Am. J. Physiol. 238 (Regulatory Integrative Comp. Physiol. 7): R328-R332, 1980] was examined in muscles and liver in response to pharmacological alterations of gluconeogenic ...
Brzezińska Z - - 1987
In order to provide reference data, adenine nucleotide, creatine phosphate, glycogen, glycolytic intermediates and lactate muscle contents were measured in 49 dogs under resting conditions and during prolonged physical exercise of moderate intensity performed until exhaustion. Both the resting and exercise values of the measured variables were remarkably similar to ...
Brooks G A - - 1987
The integrated use of several energy sources allows high muscular power outputs to be sustained. Muscle glycogen provides the major fuel source for muscular exercise, but other fuels can provide alternative energy sources which allow for muscle glycogen-sparing and an increased potential for prolonged high metabolic rates. Blood-borne glucose, derived ...
Schmidt B - - 1987
A 17-year-old boy had exercise-induced cramps and myoglobinuria. The mother had myalgia and weakness after exercise but the father was asymptomatic. Muscle biopsy was normal in the father but showed glycogen storage and absent or markedly decreased histochemical stain for phosphorylase in mother and son. Autosomal dominant McArdle's disease was ...
Peters Futre E M - - 1987
High-intensity intermittent bicycle exercise was used to deplete muscle glycogen levels by 70% and elevate blood lactate levels to greater than 13.0 mmol/l. Thereafter subjects either cycled with one leg for 45 min followed by 45 min of passive recovery (partially active recovery) or rested for 90 min (passive recovery). ...
McDermott J C - - 1987
The purpose of this study was to investigate whether epinephrine exerts an effect on glycogen metabolism in nonexercising (Non-Ex) as well as in exercising (Ex) skeletal muscle. Rats ran (15 m/min; 8% grade) on their forelimbs while their hindlimbs (Non-Ex) were suspended above the treadmill. Electromyographic records confirmed the lack ...
Kendrick Z V - - 1987
The effect of both physiological and pharmacological doses of estradiol on exercise performance and tissue glycogen utilization was determined in oophorectomized estradiol-replaced (ER) rats. Doses of beta-estradiol 3-benzoate (0.02, 0.04, 0.1, 0.2, 1, 2, 4, or 10 micrograms.0.1 ml of sunflower oil-1.100 g body wt-1) were injected 5 days/wk for ...
Lavoie J M - - 1987
The present study examines the metabolic and hormonal responses of progressive short-term food restriction in rats at rest and during exercise. The night prior to the experiment, previously cannulated rats were assigned to one of three groups: (A) normal diet, (B) 50% food restriction, and (C) 75% food restriction. They ...
Blom P C - - 1987
Muscle glycogen super-compensation, as demonstrated after exhaustive cycling, may be affected by mode of exercise and state of training. Hence, we studied the effect of exhaustive running on post-exercise changes in muscle glycogen concentration in untrained subjects and compared the effect of tapered running with an exhaustive bout of running ...
O'Reilly K P - - 1987
Five healthy untrained young male subjects were studied before, immediately after, and 10 days after a 45-min bout of eccentric exercise on a cycle ergometer (201 W). The subjects were sedentary at all other times and consumed a eucaloric meat-free diet. Needle biopsies of the vastus lateralis muscle were examined ...
Galton V A - - 1987
Conversion of T4 to T3 cannot be demonstrated in vivo in Rana catesbeiana tadpoles until just before metamorphic climax, suggesting that 5'-deiodinase (5'D) activity is not present until this time. In the present study the role of 5-deiodinase (5 D) systems in the metabolism of T4 and T3 in the ...
Kirwan J P - - 1987
Eight men were heat acclimated (39.6 degrees C and 29.2% rh) for 8 days to examine changes in substrate utilization. A heat exercise test (HET), (cycling for 60 min; 50% maximal O2 consumption) was performed before (UN-HET) and after (ACC-HET) the acclimation period. Muscle glycogen utilization (67.0 vs. 37.6 mmol/kg ...
Górski J - - 1987
Effect of adrenalectomy and exercise on skeletal muscle, heart and liver glycogen and triglycerides, blood glucose and plasma free fatty acid level has been studied in the rat. It has been found that exercise-induced mobilization of glycogen in vastus deepest and soleus was diminished whereas utilization of liver glycogen was ...
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