Prolonged Muscular Exercise Research Articles

Stress Lymphoscintigraphy for Early Detection and Management of Secondary Limb Lymphedema.

Stress lymphoscintigraphy was performed within 1 year after surgery and the completion of chemotherapy and radiation treatments. All patients were classified by the International Society of Lymphology clinical stages from 0 to 3. A dose of 50 MBq of 99mTc-HSA-nanocolloidal in 0.4mL was injected intradermally at the first and fourth intermetacarpal spaces on the hand, for the upper limb with edema, or at the first intermetatarsal space and at the lateral malleolus for lower extremities. Two planar static scans at rest were acquired immediately after tracer injection. Stress scans were acquired after weight lifting for upper extremity or stepping for 2 minutes for lower-extremity edema. After that, the patients underwent prolonged muscular exercise limited by symptoms, and later scans were acquired at 60 minutes to visualize regional lymph nodes and the effects of sustained muscular exercise. Transport Index was evaluated. Five patterns of lymphoscintigraphy were observed. In our experience, patients with types I to III pattern benefit from an exercise program as a first-line treatment. Patterns IVand V seem to be predictive of lymphedema. The abnormal patterns found may provide the basis for earlier complex physical therapy or microsurgical treatment of lymphatic disorders in patients resulting in improved outcomes.

Age effects on interleukin-6 and interleukin-1β responses to endurance exercise in patients with neuromuscular diseases

Plasma IL-6 before and 20 min after prolonged muscular exercise for 20 min at the individual aerobic/anaerobic threshold was analyzed in patients with neuromuscular diseases and in controls. Patients were assigned to the following diagnostic categories: Controls ( n=18); amyotrophic lateral sclerosis ( n=7); peripheral neuropathy ( n=6); muscular dystrophy ( n=13); mitochondriopathy ( n=3); myopathy (others) ( n=3); inflammatory myopathy ( n=6); mononeuropathy ( n=4). The concentrations of IL-6 before exercise were 5.55±0.94 pg/ml, and 6.52±0.97 pg/ml after exercise ( P=0.0001). We introduced the independent variables age, sex and diagnostic category into a stepwise multiple linear regression model. Age emerged as a significant predictor of the IL-6 ratio (IL-6 post exercise/lL-6 before exercise). The regression equation was: IL-6 ratio=0.87+0.009×age (years), R=0.33, P<0.01, simple linear regression model. All IL-1β concentrations were below the sensitivity of the assay (5 pg/ml). Concerning patients with neuromuscular diseases, the age associated increased IL-6 release after exercise could mean additional muscle damage.

Acute Renal Failure Due to Traumatic Rhabdomyolysis

Between 1990 and 1993, we studied 14 cases of acute renal failure due to prolonged muscular exercise (e.g., squat jumping, sit-ups) and blunt trauma inflicted by law enforcement personnel using sticks or leather belts. None of the patients had a prior history of myopathy, neuropathy, or renal disease. All were critically ill and required renal support in the form of dialysis. Although the morbidity was high, 13 of the patients recovered normal renal function. One patient expired due to sepsis.

Availability of glucose given orally during exercise.

Adequate utilization of glucose given orally during prolonged muscular exercise remains a matter of controversy. The aim of the present study was to investigate whether the time when glucose is ingested during exercise affects exogenous glucose disposal. Nine healthy male volunteers were submitted to a 4-h period of treadmill exercise at about 45% of their maximum O2 consumption. A 100-g load of naturally labeled [13C]glucose was given orally after 120 min (5 subj, group A) or 15 min (4 subj, group B) of exercise. In the 2 h after glucose ingestion, total carbohydrate oxidation (indirect calorimetry) was similar in both groups (A: 147 +/- 12 g/2 h; B: 135 +/- 12 g/2 h) as was lipid oxidation (A: 51 +/- 4 g/2 h; B: 57 +/- 11 g/2 h). Exogenous glucose oxidation was 54 +/- 2 g/h in group A vs. 55 +/- 6 g/2 h in group B. The blood glucose response to oral glucose was similar in the two conditions, whereas the C-peptide response, already modest, was further blunted when glucose was ingested after 2 h of exercise compared with the response observed after 15 min. In conclusion, glucose ingestion during prolonged exercise of moderate intensity is effectively oxidized, 55% of the load given being recovered as expired CO2 within 2 h; utilization of glucose given orally is similar when ingestion takes place 15 or 120 min after initiation of exercise.

Glucose utilization during exercise in normal and diabetic subjects. The role of insulin.

Due to selective isotopic effects occurring during photosynthesis, certain natural sugars are enriched in 13C Using such “naturally labeled 13C-glucose,” we studied glucose oxidation during exercise in seven normal volunteers and in six insulin-dependent diabetics after an overnight fast. In the diabetics, blood glucose was monitored the night before the test and adjusted to about 100 mg/dl by intravenous insulin infusion. The insulin infusion was withheld 15 min before exercise in four diabetics and maintained at 0.9 U/h for 2 h; then it was maintained at 0.6 U/h for 2 h in five diabetics. Three patients underwent both tests. All subjects exercised on a treadmill for 4 h at about 45% of their max. After 15 min adaptation, all received 100 g 13C-labeled glucose orally. Total glucose oxidation was derived from non-protein RQ and exogenous glucose oxidation evaluated as previously described. The diabetics had no residual B-cell function as indicated by negligible plasma C-peptide values and a lack of Cpeptide response to the oral glucose challenge. Total glucose oxidation averaged 230 ± 14 g/4 h in the normal subjects. It was similar (238 ± 19 g/4 h) in the diabetics receiving an intravenous insulin infusion, but decreased to 176 ± 14 g/4 h when no insulin was infused. Exogenous glucose oxidation was 92 ± 3 g/4 h and 84 ± 8 g/4 h (not statistically different) in the controls and in the insulin-infused diabetics, respectively. It was 43 ± 11 g/4 h in the diabetics exercising without being infused with insulin. We conclude that (1) in well-insulinized diabetic patients, prolonged muscular exercise can be performed under metabolic conditions which are basically similar to those of normal subjects; (2) during prolonged exercise, well-insulinized diabetic patients are able to oxidize up to 85–90% of a 100-g exogenous glucose load given orally and oral glucose can thus be ingested during prolonged exercise in well-controlled juvenile insulintreated diabetics; (3) even in the absence of insulin administration during exercise, juvenile diabetics who start exercising when blood glucose is near normal are able to perform a 4-h exercise at 45–50% of their max. Under these conditions, however, they are unable to utilize more than 40–45% of a 100-g glucose load given orally. They rely more upon lipid stores than the normal subjects or the well-insulinized diabetics.

The Change in Physical Working Capacity Shown as PWC&lt;sub&gt;120&lt;/sub&gt;, PWC&lt;sub&gt;150&lt;/sub&gt; and PWC&lt;sub&gt;170&lt;/sub&gt; during Prolonged Muscular Exercise

The purpose of this investigation is to study the relations between the physical working capacity and rectal temperature during muscular exercise.Subjects were six healthy male young adults (Table 1). 60 minutes bicycle exercises were carried out at work rates requiring 30, 40, 50 and 60% of the subjects' maximal oxygen uptake. Heart rate and rectal temperature were measured every ten minutes during the works. Rectal temperatures ranged between 36.95dC and 39.00dC while exercising (Table 2) and were classified into five groups (-37.35dC, 37.36-37.70dC, 37.71-38.05dC, 38.06-38.40dC, 38.41dC-). PWC120, PWC150, and PWC170 were calculated from the regression equations of work rate on heart rate at their respective rectal temperature groups (Table 3). It was observed that PWC150 and PWC170 had a decreasing tendency at the higher rectal temperatures. Analysis of variance confirmed that the rectal temperature effect was nearly significant (Table 4).This result means that the body temperature and working time have to be taken into consideration in evaluating to physical working capacity at least by means of using the relationship between heart rate and work rate.

Effect of glucose ingestion on energy substrate utilization during prolonged muscular exercise.

The distribution of substrates utilized during prolonged exercise was investigated in normal human volunteers with an without ingestion of 100 g exogenous glucose. The energy provided by protein oxidation was derived from urinary nitrogen excretion and the total energy provided by carbohydrates and lipids was calculated from respiratory quotient (RQ) determinations. The contribution of exogenous glucose to the energy supply was determined by an original procedure using "naturally labeled 13C-glucose" as metabolic tracer. Protein oxidation provided between 1 and 2% of the total energy requirement; this amount was not affected by glucose ingestion. In the absence of exogenous glucose ingestion, carbohydrate were progressively replaced by lipids as source of energy. Exogenous glucose contributed markedly to total carbohydrate oxidation and decreased the percentage of energy derived from lipids. In addition, ingestion of exogenous glucose resulted in a significant economy of endogenous carbohydrates and permitted to prolong the duration of exercise.

Serum TSH and prolactin levels during prolonged muscular exercise.

Serum TSH and prolactin levels during prolonged muscular exercise.

Role of growth hormone in lipid mobilization stimulated by prolonged muscular exercise in the rat.

The effects of prolonged muscular exercise (swim in tepid water for 60 min) on blood glucose, plasma FFA and R-GH were studied in a group of normal rats and the effect on blood glucose and plasma FFA in a group of hypophysectomized rats. The data obtained showed that, whereas in normal rats plasma FFA rose after muscular exercise, plasma R-GH fell sharply. In Hypophysectomized rats, however, muscular exercise did not increase plasma FFA levels.

Inhibitory Effect of Amitriptyline on Exercise-Induced Lipid Mobilization in Rats

The effects of administration of Amitriptyline on lipolysis induced by prolonged muscular exercise in rats were investigated.

Adrenocortical activation during long-term exercise in dogs: evidence for a glucostatic mechanism.

Experiments were performed to elucidate the mechanism of changes in plasma 17-OHCS level during prolonged muscular exercise of moderate intensity. Dogs performed 120 min standard treadmill exercise. Plasma level of 17-OHCS increased during exercise. There was no change in the rate of removal of intravenously injected cortisol as compared with resting conditions. Exercise-dependent increase in plasma 17-OHCS level was prevented by continuous intravenous glucose infusion at a rate sufficient to prevent exercise hypoglycaemia. The same result was obtained when systemic hypoglycaemia persisted but glucose supply to the brain or liver was augmented by continuous glucose infusion to the carotid artery or portal vein. The same amount of glucose infused into a peripheral vein failed to abolish the adrenocortical response to exercise. The insulin-evoked hypoglycaemia of the magnitude comparable to that obtained during standard exercise did not significantly affect plasma 17-OHCS in resting animals.

The Influence of Anoxia on Lactate Utilization in Man after Prolonged Muscnlar Work

Summary.A slight modification of Barker and Summerson's method of lactic acid determination is described.The rates of lactate utilization, urinary lactate excretion and blood glycolysis during recovery from prolonged muscular exercise were studied in two subjects working on a bicycle ergometer. The results indicate that under the specified conditions the rate of lactate utilization is not significantly altered by anoxia caused by inhalation of low percentage oxygen mixtures. the rate of blood glycolysis is low compared with the utilization rate of lactate and is independent of the blood lactate level. the rate of urinary lactate excretion is very low compared with the utilization rate of lactate. and is independent of anoxia. The difficulties in determining the chemical order of the lactate utilization processes are discussed.

The effects of prolonged muscular exercise on the metabolism

The Journal of PhysiologyVolume 93, Issue 2 p. 144-158 ArticleFree Access The effects of prolonged muscular exercise on the metabolism J. N. Mills, J. N. MillsSearch for more papers by this author J. N. Mills, J. N. MillsSearch for more papers by this author First published: 14 July 1938 https://doi.org/10.1113/jphysiol.1938.sp003632Citations: 6AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume93, Issue2July 14, 1938Pages 144-158 RelatedInformation

The effects of prolonged muscular exercise on the metabolism

During recent years a great deal of attention has been devoted to the changes in metabolism which result from very hard muscular work, in the main with the idea of correlating the alterations in the respiratory exchange and in the composition of the blood with the chemical changes responsible for the energy of muscular contraction in the isolated muscle under both aerobic and anaerobic conditions, This work, valuable though its results have been, has tended to divert attention away from another aspect of muscular work which is none the less of great practical importance. In everyday life the muscular work which we are called upon to perform is done at a far lower rate than that which is done by the athlete who is pushing himself almost to the limit of his power. It by no means follows that the facts observed during severe exercise, and the deductions made from these, can be applied without alteration when we wish to explain the effects of exercise of far less severity. It is true that there have been in the past many studies of the physiology of moderate muscular work, but when these are examined in detail they prove to be rather incomplete. As a rule those who have undertaken these investigations have devoted themselves to some limited aspect of the problem, such as the efficiency with which the work is performed under a variety of conditions, the influence of alterations of the diet on the capacity of an individual to do muscular work, or the vexed question of the relative importance of carbohydrate and fat as sources of energy during the performance of the work, and whilst much stress has been laid on events during the actual work too little attention has been given to changes which may result from the work and become apparent during a subsequent period of rest. It therefore seemed to us desirable to study in more detail the effects of prolonged though moderate muscular work, in the hope in particular of throwing further light on the significance of changes of the respiratory quotient, the interpretation of which is admittedly always a very difficult and troublesome problem, as may be gathered from the observations of Cathcart and Markowitz (1927) and he recent review of Rapport (1930), although it is one that must be faced if we are to gain an insight into the metabolic changes involved.

Influence of Excessive and Prolonged Muscular Exercise upon the Elimination of Effete Matters by the Kidneys

Influence of Excessive and Prolonged Muscular Exercise upon the Elimination of Effete Matters by the Kidneys