Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to examine the effects of ingesting a carbohydrate-electrolyte solution on endurance capacity during a prolonged intermittent, high-intensity shuttle running test (PIHSRT). Nine trained male games players performed two exercise trials, 7 days apart. On each occasion, they completed 75 min exercise, comprising of five 15-min periods of intermittent running, consisting of sprinting, interspersed with periods of jogging and walking (Part A), followed by intermittent running to fatigue (Part B). The subjects were randomly allocated either a 6.9% carbohydrate-electrolyte solution (CHO) or a non-carbohydrate placebo (CON) immediately prior to exercise (5 ml kg-1 body mass) and every 15 min thereafter (2 ml kg-1 body mass). Venous blood samples were obtained at rest, during and after each PIHSRT for the determination of glucose, lactate, plasma free fatty acid, glycerol, ammonia, and serum insulin and electrolyte concentrations. During Part B, the subjects were able to continue running longer when fed CHO (CHO = 8.9 +/- 1.5 min vs CON = 6.7 +/- 1.0 min; P < 0.05) (mean +/- S.E.M.). These results show that drinking a carbohydrate-electrolyte solution improves endurance running capacity during prolonged intermittent exercise.
 ...
PMID:Influence of ingesting a carbohydrate-electrolyte solution on endurance capacity during intermittent, high-intensity shuttle running. 747 41

The basic scientific achievements of the Department of Biochemistry of Muscles organized at the Academy of Sciences of Ukrainian SSR in 1944 are presented in this short historical overview. The basic guidelines for activities in the scientific field are as follows: study of biochemical processes in the working muscles as well as during misfunctions and disabilities, processes of adenine nucleotides exchange and ammonia creation, biochemical characterization of Ca2+ and H+ transport through the plasma and sarcoplasmic reticulum membranes. It is shown that creatine and creatine phosphate as well as adenine nucleotide content and metabolism affect the muscle functioning, glycogen metabolism proceeds simultaneously with the lowering of content of inorganic phosphate. The facts of glucose phosphorylation and its conversion via glycolytic pathways and the backward reaction of glycolysis (the aerobic synthesis of phosphopyruvate, glycogen synthesis from glucose in the presence of phosphorylase) were determined. After the muscle work up to tiredness adenine nucleotide depletion is not limited by its dephosphorylation, but goes up to formation of inosine acid and ammonia. Deamidation is shown to be in myofibrillar fraction and in sarcoplasmic reticulum of the skeletal muscle. Deamidation activity is not registered in myocardium myofibrillar fraction but it is registered in sarcoplasmic reticulum. AMP-phosphohydrolase and adenosine desaminase were found in membranes of the sarcoplasmic reticulum. The decrease in activity of all enzymes mentioned above is registered during myocardium hypertrophy, because of aorta narrowing. These data permit creating the methods for obtaining substance "adenosine phosphate" for treatment of cardiac pathologies. Glutaminase was found to be active in the muscles. This activity depended on the organism functioning. The ammonia usage by the muscle cells goes with glutamine synthesis and consumption of energy of ATP, e.g. protein amidation. The later is of all-biological significance and is used in the fields of medicine actualls concerned with the following fact: the velocity of hydrolysis of amidated protein is different for such pathology as epilepsia, tuberculosis, poisoning with manganese oxides. The methods for diagnostics of the above pathological states were developed on this basis. It is proved that glutamine nitrogen can be also used in the reaction of transamination, particularly during synthesis of purines, inosine acid and it is stored in a form of glutaminic acid. Changes in carbohydrate and phosphorus metabolism, in nitrogen and energetic exchanges and mitochondria overfilling with calcium were determined under E-avitaminosis dystrophy.(ABSTRACT TRUNCATED)
 ...
PMID:[Department of the Biochemistry of Muscles]. 757 Oct 74

Adenine nucleotide (AN) degradation has been shown to occur during intense exercise in man and in the horse, at or close to the point of fatigue. The aim of the study was to compare plasma ammonia concentration ([NH3]) as a result of intense exercise with plasma [lactate]. Plasma glutamine concentration ([Gln]) was also measured pre- and post-exercise. On separate occasions, nine healthy subjects (two females) exercised on a motorised treadmill for periods of between 30 s and 210 s, at 5.6 m.s-1 (0% incline). On one occasion, running at the same speed, two subjects ran at +4% incline whilst one other subject ran at +7% incline. Blood samples were taken and plasma was analysed for [lactate], [NH3] and [Gln]. Subjects showed varying degrees of AN degradation as indicated by plasma [NH3]. A comparison of plasma [NH3] with that of plasma [lactate] indicated a marked increase in AN degradation, corresponding to a [lactate] of around 14 mmol.l-1 in plasma. The data further support the hypothesis that there is a critical intramuscular pH below which there is a stimulus to AN degradation during intense exercise, possibly as a result of a substantial reduction in the kinetics of adenosine diphosphate (ADP) rephosphorylation provided by phosphocreatine, resulting in an increase in [ADP].
 ...
PMID:Hyperammonaemia in relation to high-intensity exercise duration in man. 785 72

Electrolytes are essential to normal skeletal muscle contraction and are thought to play a role in muscle fatigue. Excess accumulation of ammonia and hydrogen ions after strenuous bouts of physical activity are thought to slow muscle contractions and decrease muscle tension development. Certain disease states cause abnormal levels of such electrolytes as calcium, magnesium, potassium, or sodium. Excessively high or low levels of these ions in the serum are associated with symptoms such as muscle weakness or cramping. Nurses should know the effects of abnormal electrolyte levels on muscle function in the assessment and treatment of their patients.
 ...
PMID:Electrolytes and their relationship to normal and abnormal muscle function. 785 27

1. Exercise and beta-adrenoceptor blockade have important roles in the prevention and treatment of cardiovascular disease, but fatigue and a reduced capacity to exercise are commonly reported side effects of beta-adrenoceptor blockers. The reduced capacity to exercise may be partly caused by a reduction in fat metabolism. 2. We investigated the effects of atenolol 50 mg, metoprolol CR/Z0K 50 mg, metoprolol CR/Z0K 100 mg and placebo, on heart rate, energy expenditure, fat oxidation, plasma free fatty acids, glycerol, glucose, lactate, ammonia and perceived exertion during 2 h of treadmill walking at 40% of maximal oxygen uptake in 20 healthy volunteers. 3. Compared with placebo (38.0%), total fat oxidation was significantly lower on atenolol 50 mg (30.1%) and metoprolol CR/Z0K 100 mg (31.0%), but not on metoprolol CR/Z0K 50 mg (33.7%). Reductions in fat oxidation correlated well (r2 = 0.970) with reductions in exercising heart rate, and probably reflected the degree of beta 1-adrenoceptor blockade. Maximum plasma ammonia concentration was reached after 45 min of exercise on atenolol, 60 min on metoprolol CR/Z0K 100, and 75 min on metoprolol CR/Z0K 50, and was higher than placebo on all active drug treatments. 4. The greater reduction in fat oxidation with atenolol may be a reflection of a peak in plasma concentration, which is avoided with a controlled release preparation.
 ...
PMID:Exercise metabolism in healthy volunteers taking atenolol, high and low doses of metoprolol CR/Z0K, and placebo. 788 87

The purpose of this study was to examine the effect of glutamate-arginine salt (AGs) or placebo (P1) on ammonemia during and after 1 hour exercise on sporting event bicycle under ergonomic device at 80% VO2max in 3 healthy male volunteers (age 18-25 years). Subjects were tested in three sessions, at rest after AGs and during exercise with placebo (Pl) or AGs. The subjects were given 20 g of AGs or Pl orally and 30 min later, exercised at 75-80% VO2max for 30 min. Blood samples were taken at 0, +30, +60, +90, +120 min after AGs and analyzed for ammonemia. Our results show a highly significant increase in plasma ammonia concentration during exercise. The magnitude of this increase was diminished when subjects were given AGs before the exercise session, suggesting that AGs may help reduce physiologic fatigue.
 ...
PMID:Effects of an ingested glutamate arginine salt on ammonemia during and after long lasting cycling. 800 36

The Lymphapress, a pneumatic sequential intermittent device is recognized as one of the most effective conservative treatments for lymphoedema, due to its effective 'milking mechanism'. This led us to hypothesize that accelerated removal of fatigue-causing metabolites by mechanical massage could improve an athlete's performance capacity. We conducted trials with 11 men who exercised at a constant workload, on a cycle ergometer, until exhaustion. During a 20-min recovery period a new modified pneumatic sequential intermittent device (the MISPD) was applied to the subjects' legs. The men then performed a second constant load exercise bout. Cardiorespiratory parameters were measured during exercise and blood was withdrawn during recovery for the determination of lactate, pyruvate, ammonia, bicarbonate and pH. No difference was found in the blood levels of the 'fatigue causing metabolites' during passive recovery (PR) and recovery with the MISPD (MR). However, the MISPD effected a 45% improvement in the subjects' ability to perform the subsequent exercise bout. The accumulation of fluid in the interstitial space after exercise and its disappearance after the use of the MISPD offers one possible explanation for these results, although psychological effects cannot be discounted.
 ...
PMID:The effects of the modified intermittent sequential pneumatic device (MISPD) on exercise performance following an exhaustive exercise bout. 813 Sep 64

Six female subjects, aged 24-34 years, performed shoulder-neck exercise for 1 h or until they were exhausted by holding out their arms horizontally at 60 degrees to the sagittal plane. One continuous and six intermittent protocols were applied, all with a mean load corresponding to the torque of the arms, i.e. about 15% maximal voluntary contraction (MVC). The intermittent protocols varied according to cycle time (10 s, 60 s, 360 s) and duty cycle (0.33, 0.50, 0.67, 0.83). Electromyogram (EMG), mean arterial blood pressure (BPa), heart rate (fc) and perceived fatigue were monitored at regular intervals during exercise. Blood concentrations of potassium, lactate and ammonia were determined in pre- and postexercise samples of venous blood. Before and up to 4 h after exercise, measurements were made of MVC, pressure pain threshold, proprioceptive performance, and of EMG, BPa and fc during 1-min arm-holding at 25% MVC. Endurance times ranged from about 10 min to more than 1 h, significantly relating to both cycle time and duty cycle. The BPa, fc, EMG amplitude and perceived fatigue increased early during all protocols and continued to increase throughout the exercise period. Duty cycle influenced all of these variables, while only BPa and fatigue perception were related to cycle time. Cardiovascular and neuromuscular recovery was incomplete for hours after several of the protocols, as indicated for example by a sensitized response to the 1-min arm-holding. The protocols differed substantially as regards the relationship between different responses. Thus, ranking of the protocols in terms of physiological strain was different, depending on the criterion variable. The result stresses the relevance of applying a comprehensive selection of variables when evaluating the responses to intermittent shoulder-neck exercise.
 ...
PMID:The influence of exercise/rest schedule on the physiological and psychophysical response to isometric shoulder-neck exercise. 814 33

The authors report two cases of hepatic encephalopathy with chronic hepatic failure. Case 1 was a 78-year-old woman with liver cirrhosis, admitted because of general fatigue and loss of appetite. Her electroencephalogram showed frequent slow waves in the theta range with intermittent triphasic waves T1-weighted MR images showed increased signal intensity in the globus pallidus and the putamen. Case 2 was a 71-year-old woman with chronic hepatitis, admitted because of depression. Her electroencephalogram showed frequent slow wave activities in the theta-delta range with intermittent trisphasic waves. Her serum ammonia level was 84 micrograms/dl (normal 12-54 micrograms/dl). T1-weighted MR images showed increased signal intensity in the globus pallidus, the putamen and the hypothalamus. On the basis of these findings, both patients were diagnosed as having hepatic encephalopathy, although disturbance of consciousness was not obvious. The observed MR image abnormalities might be due to the metabolic and pathological changes of chronic hepatic failure. Such MRI findings may be useful for the diagnosis of hepatic encephalopathy.
 ...
PMID:[Two cases of hepatic encephalopathy associated with a high-intensity area in the basal ganglia on T1-weighted MR images]. 823 Jul 86

The influence of increased carbohydrate intake on endurance capacity was investigated following a bout of prolonged exercise and 22.5 hrs of recovery. Sixteen male subjects were divided into two matched groups, which were then randomly assigned to either a control (C) or a carbohydrate (CHO) condition. Both groups ran at 70% VO2max on a level treadmill for 90 min or until volitional fatigue, whichever came first (T1), and 22.5 hours later they ran at the same % VO2max for as long as possible to assess endurance capacity (T2). During the recovery, the carbohydrate intake of the CHO group was increased from 5.8 (+/- 0.5) to 8.8 (+/- 0.1) g kg-1 BW. This was achieved by supplementing their normal diet with a 16.5% glucose polymer solution. An isocaloric diet was prescribed for the C group, in which additional energy was provided in the form of fat and protein. Run times over T1 did not differ between the groups. However, over T2 the run time of the C group was reduced by 15.57 min (p < 0.05), whereas those in the CHO group were able to match their T1 performance. Blood glucose remained stable throughout T1 and T2 in both groups. In contrast, blood lactate, plasma FFA, glycerol, ammonia, and urea increased. Thus, a high carbohydrate diet restored endurance capacity within 22.5 hrs whereas an isocaloric diet without additional carbohydrate did not.
 ...
PMID:Carbohydrate intake and recovery from prolonged exercise. 850 93


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>