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PubMedDate not supplied

The relationship between physical exercise and distress in a national sample of Canadians.

This paper presents an empirical examination of the relationship between physical exercise and generalized distress within a stress process framework by examining how chronic strains, self-esteem, mastery, and social support influence this relationship. The analysis employed the 1994 wave of the National Population Health Survey consisting of a sample of 12,636 Canadians between 20 and 64 years of age. Findings suggest that physical exercise is a significant predictor of generalized distress independent of chronic strain, self-esteem and social support. However, mastery mediated the association between physical exercise and distress. Moreover, mastery moderated the relationship indicating that it is a more important resource for people who are inactive.

Adolescent↗
PubMed1998

Influence of physical exercise on human preferences for various taste solutions.

The effects of physical exercise on preference for various sapid solutions was studied in 58 healthy university students. After 30 min of exercise using a bicycle ergometer at 50% VO2max (maximal oxygen uptake) intensity, a rating scale test on taste hedonic tone and the triangle test for taste absolute threshold were done. The test solutions were sucrose, NaCl, citric acid, caffeine and monosodium glutamate (MSG). Preference scale values for sucrose and citric acid increased after exercise, whereas the values for NaCl, caffeine and MSG were not changed. The absolute thresholds for all the sapid solutions did not differ for pre- and post-exercise. These findings indicate that in humans preference for sucrose and citric acid increase after physical exercise.

Adult↗
PubMedDate not supplied

Evaluation of nasal volume by acoustic rhinometry before and after physical exercise.

BACKGROUND: The nasal structures generate airflow resistance that can reach -50% of the total respiratory resistance. There are a series of factors that can alter the volume of these structures, among them physical exercise. The objective of this study was to determine the degree of changes in nasal volume at different levels of physical exercise, evaluating the influence of exercise intensity and duration, as well as the duration of the effect of exercise on the nasal mucosa. METHODS: Nineteen individuals were submitted to three distinct physical tests on a cycle ergometer: test 1, exercising for 5 minutes on a cycle ergometer at 50% the maximal load; test 2, exercising for 10 minutes on a cycle ergometer at 50% the maximal load; and test 3, exercising for 5 minutes on a cycle ergometer at 75% the maximal load. In each test, nasal volume was measured by acoustic rhinometry immediately after the end of exercise and 10 and 20 minutes thereafter. RESULTS: The rhinometry results showed a significant increase (p < 0.001) in nasal volume after physical exercise for all tests performed. At 20 minutes, nasal volume had returned close to resting levels in all three tests. Comparison of the degree of improvement of nasal volume between the three physical tests showed a significant difference (p < 0.05) between T1 and T2 (T2 presented gain of 8.3% more in nasal volume than T1). Test 3 showed no significant difference (p > 0.05) compared with the other two tests, with 5.8% higher gain in nasal volume observed compared with T1, while the increase was 2.5% lower than in T2. CONCLUSION: Physical exercise in general causes a significant increase in nasal volume, with the duration of exercise exerting a greater effect on the degree of improvement than intensity.

Adolescent↗
PubMed2006

Impact of the "Planning to be Active" leisure time physical exercise program on rural high school students.

PURPOSE: The purpose of the study was to evaluate the effects of a Social Cognitive Theory-based intervention designed to increase the frequency of leisure time planned moderate and vigorous physical exercise among rural high school students attending physical education class. METHODS: Students in treatment and comparison groups were exposed to an activity-based physical education curricula. The treatment group received eight behavioral skill-building lessons integrated into the existing curriculum. RESULTS: The Social Cognitive Theory-based educational treatment increased levels of moderate physical exercise occurring outside the classroom. CONCLUSIONS: This study demonstrated an impact on adolescent leisure time moderate physical exercise using classroom instruction. The intervention was most effective with students who were previously sedentary. The curricular approaches used to promote regular moderate exercise may be useful for sedentary adolescents.

Adolescent↗
PubMed2005

Physical exercise increases the expression of TNFalpha and GLUT 1 in muscle tissue of diabetes prone Psammomys obesus.

INTRODUCTION: Tumor necrosis factor-alpha (TNFalpha) is a major mediator of insulin resistance. On the other hand, it has been suggested that TNFalpha may facilitate glucose uptake through GLUT 1 expression. We recently found that physical exercise prevented the progression to type 2 diabetes mellitus in diabetes prone Psammomys obesus (sand rat). AIM: The aim of the present study was to characterize the influence of physical exercise on the expression of TNFalpha, its receptor R1 and GLUT 1 in muscle tissue of this animal model. METHODS: Animals were assigned for 4 weeks to four groups: high-energy diet (HC), high-energy diet and exercise (HE), low-energy diet (LC), low-energy diet and exercise (LE). TNFalpha, R1 and GLUT 1 expression were analyzed using Western blot technique. RESULTS: None of the animals in the HE group became diabetic while all the animals in the HC group became diabetic. TNFalpha, its receptor (R1) and GLUT 1 expressions were significantly higher in the two exercising groups (LE and HE) and significantly lower in the HC group compared to the control LC group. CONCLUSIONS: Physical exercise augments the expression of TNFalpha, its receptor R1 and the glucose transporter GLUT 1 in muscle tissue. We suggest that this mechanism may improve glucose uptake through pathways parallel and unrelated to insulin signaling that may include MAPK and/or NO. These biochemical processes contribute to the beneficial effects of physical exercise on the prevention of type 2 diabetes mellitus.

Animals↗
PubMed1988

Effects of voluntary physical exercise on cardiac function and energetics in spontaneously hypertensive rats.

The influence of voluntary physical exercise in running wheels on myocardial function, cardiac oxygen utilization and cardiovascular response to emotional stress was analysed in the spontaneously hypertensive rat. After 6 weeks of exercise, a significant increase in resting cardiac output was found, which was due to an elevation of stroke volume. However, voluntary training for 12 weeks had no effect on resting blood pressure or on the blood-pressure response to mental stress. Cardiac function was also examined in vitro. At a low aortic diastolic pressure, it was markedly augmented in trained spontaneously hypertensive rats. At high aortic diastolic pressure, maximal cardiac function was similar in the two groups. Myocardial oxygen consumption (mumol min-1 g-1) for a given level of external work was reduced in trained, compared with non-exercised control spontaneously hypertensive rats. Chronic physical exercise thus greatly improved myocardial function at a subnormal perfusion pressure, suggesting better nutritional supply to the myocardium, probably created by an increased capillary surface area.

Animals↗
PubMed2004

Growth hormone, cortisol and prolactin responses to physical exercise: higher prolactin response in depressed patients.

This study was designed to compare growth hormone, cortisol and prolactin responses to physical exercise in depressed patients and healthy comparison subjects. Patients fulfilled the DSM-IV diagnostic criteria for current major depressive disorder; subjective depressive symptoms were rated with Montgomery-Asberg Depression Rating Scale (MADRS) immediately before the experiment. Growth hormone, cortisol and prolactin were measured before and immediately after physiologically stressful bicycle cardiopulmonary exercise test. After exercise, there were three additional hormone measurements, with 30-min intervals. No significant difference was found in baseline growth hormone, cortisol or prolactin levels between patients and the control group. Plasma growth hormone and cortisol levels increased significantly during physical exercise in both patients and controls and returned to baseline in 90 min. There was no significant difference in growth hormone or cortisol responses to physical exercise between the two groups. However, prolactin levels increased only in the depressed patients group during the exercise. We hypothesize that acute exercise may have a stronger effect on serotonin (5-HT) release in depressed patients, which is reflected in increased plasma prolactin concentration.

Adult↗
PubMedDate not supplied

[Effect of physical exercise conducted at various times of the day on the regulation of carbohydrate metabolism in patients with diabetes mellitus].

A study was made of the levels of glucose, IRI, STH, ACTH and cortisol in the blood serum (plasma) of 39 patients with diabetes mellitus prior to and after physical exercise testing. 25 patients performed physical exercises on an empty stomach in the morning (8-9 a.m.) 14 patients in the daytime (4-5 p.m.). Exercise therapy in the morning hours resulted in the readjustment of hormonal regulation characterized by the predominance of the activity of the counterinsular systems over the insular one. In the daytime the IRI level in patients with diabetes mellitus increased and the activity of the hypophyseoadrenal system before and after physical exercise testing decreased as compared to morning indices producing a beneficial effect on the carbohydrate metabolic status. Daytime hours seem optimum for exercise therapy of patients with diabetes mellitus of both types.

Adolescent↗
PubMed1996

Effects of voluntary physical exercise on high-fat diet-promoted pancreatic carcinogenesis in the hamster model.

We examined the effect of voluntary physical exercise (running wheels) on pancreatic carcinogenicity of N-nitrosobis-(2-oxopropyl) amine (BOP) in groups of female Syrian hamsters fed a high-fat (HF) diet in which corn oil was 24.6% of the diet or a low-fat (LF) diet in which corn oil was 4.5% of the diet. Each group was divided into an exercising (EX) group (LF-EX and HF-EX) and a sedentary (S) group (LF-S and HF-S). All hamsters were treated with BOP (20 mg/kg body wt) weekly for two weeks beginning four weeks after the experimental diets, which were fed from weaning. A modified glucose tolerance test was performed before the BOP injections and then again at 20 and 40 weeks, and the levels of glucose, insulin-like growth factor I, and insulin were determined in the plasma samples. At the end of the experiment, serum levels of lipid metabolites were also examined in six hamsters from each group. The experiment was terminated 44 weeks after the BOP treatment. Pancreatic ductal/ductular adenocarcinoma incidence was significantly higher in hamsters fed the HF diet (HF-S and HF-EX) than in those fed the LF diet (LF-S and LF-EX). In all groups, glucose and insulin-like growth factor I levels remained within the normal range throughout the experiment, whereas insulin and lipid metabolite levels were significantly elevated in all hamsters fed the HF diet (HF-S and HF-EX). Exercise significantly reduced the insulin level in the group fed the HF diet but did not influence the cancer burden, possibly by the generation of reactive lipid metabolites. Overall, the results showed that voluntary physical exercise does not influence the promotional action of the HF diet on pancreatic carcinogenesis in hamsters. This action could be attributed to the ability of the HF diet to increase the secretion of insulin, which has a growth-promoting and mitogenic effect on pancreatic cells, and to the effect of an HF diet or physical exercise in producing excess free radicals.

Adenocarcinoma↗
PubMed2002

Retained fibrinolytic response and no coagulation activation after acute physical exercise in middle-aged women with previous myocardial infarction.

Sudden physical exertion is associated with an increased risk of acute myocardial infarction (MI) and sudden cardiac death. In addition, activation of the coagulation cascade and/or reduced fibrinolytic capacity after physical exercise has been reported in patients with cardiovascular disease. We investigated the haemostatic responses to an acute submaximal physical exercise in middle-aged women with a history of MI compared with healthy, age-matched controls. Resting plasma von Willebrand factor antigen (vWF Ag) and tissue plasminogen activator (tPA) antigen concentrations and plasminogen activator inhibitor-1 (PAI-1) activity were higher in the patients compared with control subjects. After 30 min of submaximal exercise on a bicycle ergometer, small, but still significant, increases in fibrinogen and vWF Ag concentrations were found in both groups. However, exercise did not induce thrombin generation and fibrin formation, as assessed by thrombin-antithrombin complex and fibrin D-dimer, in either group. Both tPA antigen concentration and activity increased and PAI-1 activity decreased significantly with exercise in both groups. Interestingly, the magnitude of changes in these latter variables did not differ between the groups (P=.99, P=.88 and P=.24, respectively). The present study demonstrates that some middle-aged women with previous MI have no signs of coagulation activation and retained fibrinolytic response after submaximal exercise. The clinical implication of these results might be that women with stable coronary heart disease can participate in rehabilitative exercise training without exhibiting a procoagulative state.

Aged↗
PubMed2006

Physical exercise facilitates motor processes in simple reaction time performance: an electromyographic analysis.

The aim of the current study was to assess the effects of physical exercise on simple reaction time performance. Participants performed a simple reaction time task twice, one time during physical exercise and another time without exercise. Electromyographic signals were recorded from the thumb of the responding hand to fraction reaction time in pre-motor and motor time. The results showed that exercise shortened motor time but failed to affect pre-motor time. This pattern of findings is consistent with previous studies examining the effects of physical exercise on choice reaction time.

Adult↗
PubMed2005

Disparity between dobutamine stress and physical exercise magnetic resonance imaging in patients with an intra-atrial correction for transposition of the great arteries.

BACKGROUND: In patients with an intra-atrial correction for transposition of the great arteries (TGA) an abnormal response to stress testing is common. However, hemodynamic responses may vary substantially when different stress tests are used. We compared the hemodynamic response to dobutamine stress with the response to physical exercise in patients and controls. METHODS: Thirty-nine patients and 25 age/sex-matched control subjects underwent either dobutamine stress (15 microg/kg/min) or submaximal physical exercise cardiovascular magnetic resonance. End-systolic and end-diastolic right ventricular volumes (ESV; EDV) were determined. Five representative patients underwent both stress tests. For these patients, wall thickening reserve was calculated as systolic wall thickening during stress minus systolic wall thickening at rest. RESULTS: In controls, dobutamine stress and physical exercise showed similar responses: stroke volume, cardiac output, and ejection fraction increased significantly, whereas ESV decreased significantly and EDV was unchanged. In patients, stroke volume did not increase with either dobutamine or exercise (-8.6% vs. 2.9%). Ejection fraction increased significantly with dobutamine (16%, p < 0.001) but tended to decrease during exercise (-2.1%, P = NS). EDV and ESV decreased during dobutamine but were unchanged during exercise. (-22% vs. 5.0%, P < 0.001; -36% vs. 9.0%, P < 0.01 respectively). Wall thickening reserve was higher with dobutamine than with exercise (0.9 mm vs. -0.6 mm, P = 0.02). CONCLUSION: Dobutamine stress and physical exercise cannot be used interchangeably for assessment of systolic and diastolic function in patients with an intra-atrial correction for TGA. This may have consequences for the use of different stress CMR approaches in the clinical setting.

Adult↗
PubMedDate not supplied

Creatinine excretion in urine of man under hypokinesia and physical exercise.

It was assumed that creatinine loss in urine of man may increase or decrease under hypokinesia (diminished muscular activity) and physical exercise. Thus the aim of this study was to calculate creatinine excretion in urine of 12 healthy men, aged 19-23, under 100-days' exposure to hypokinesia (HK) and PE. They were divided into two groups, with 6 men in each. The 1st group of men was subjected to pure HK and the 2nd group was submitted to combined HK and PE. For the simulation of the hypokinetic effect both groups of men were kept under 100 days of ad-libitum bedrest protocol. A full nutritions diet was given to both groups of men. The creatinine excretion in urine was measured by conventional methods. By the 18th day of hypokinesia an increase in the rate of excretion of creatinine in urine was demonstrated, and by the 55th day there was a more pronounced increase in creatinine excretion. Physical exercise failed to diminish creatinine excretion. It was concluded that hypokinesia and physical exercise increased creatinine excretion in urine of man.

Adult↗
PubMedDate not supplied

[Hydration status and aerobic capacity: effects on plasmatic volume during strenuous physical exercise].

INTRODUCTION: During exercise, water loss frequently occurs in the intracellular spaces and there is a decrease in the plasmatic volume, with a blood concentration as a secondary characteristic. Plasmatic volume losses provoke a decrease in the blood flow, which directly affects cardiac function. Physical performance decreases and aerobic capacity deteriorates. MATERIAL AND METHODS: An observational, prospective, longitudinal, and comparative study was carried out to evaluate gender influence and the aerobic capacity level upon hydration and the plasmatic volume produced by maximal physical exercise. Twenty four individuals between 18 and 35 years old were included. All participated in aerobic physical exercise and changes in hemoglobin, hematocrit, plasmatic volume, and hydration state were evaluated. RESULTS: Gender showed a significant influence on plasmatic volume but not on the hydration state. The aerobic capacity presented a relationship with plasmatic volume, and the plasmatic volume with the hydration state. Women presented more plasmatic volume loss than men (p < 0.05). Individuals who have adequate aerobic capacity tend to lose less plasmatic volume during exercise. CONCLUSIONS: Maximal physical exercise during a short period also leads to important liquid loss; therefore, it is important that people who engage in exercise understand their liquid losses and re-hydrate themselves appropriately before, during, and after exercise.

Adolescent↗
PubMed1999

Free radical scavenging activity in the nonenzymatic fraction of human saliva: a simple DPPH assay showing the effect of physical exercise.

Free-radicals and other reactive oxygen species (ROS) have been implicated as being major damaging species in pathology and they have been widely investigated. Using 1,1'-diphenyl-2-picrylhydrazyl (DPPH), we estimated total free radical scavenging activity in the low-molecular-weight nonenzymatic fraction (LMNEF) of human whole saliva. The activity of the whole saliva and serum were measured in terms of the rate of decrease in the absorbance at 517 nm in a 40% ethanol DPPH solution (pH 7.4) at room temperature. The DPPH activity of saliva and serum showed a significant linear relationship. The mean DPPH activities of saliva from 257 subjects aged 4-72 was found to be 0.389+/-.190 micromol/ml and bore no relation to age or sex. The activity in saliva of 86 subjects aged 4-11 was significantly different before and after exhaustive aerobic dance exercise for 1 hr. Physical exercise markedly decreased free radical scavenging activity in whole saliva of children. On the basis of the above results, we concluded that DPPH is useful for evaluating the total antioxidant capacity of LMNEF of human saliva.

Adolescent↗
PubMed2006

Low back pain in a general population. Natural course and influence of physical exercise--a 5-year follow-up of the Musculoskeletal Intervention Center-Norrtälje Study.

STUDY DESIGN: A 5-year prospective cohort study was conducted of men and women seeking care for a new period of low back pain (LBP). OBJECTIVES: To study the natural course of pain and disability due to LBP during a 5-year follow-up period, and to investigate the possible influence of regular physical exercise on recovery. SUMMARY OF BACKGROUND DATA: LBP is major health problem, but its natural course is not very well studied. Several studies have investigated the role of physical exercise on LBP disorders, with inconsistent results. METHODS: At baseline, a total of 790 subjects seeking care for LBP were interviewed about physical exercise during leisure time. Over 5 years, 3 follow-up assessments were made by postal questionnaire. At all measuring points, pain intensity ratings and disability scores were compared between men and women, and among 3 exercise categories. RESULTS: The pain intensity and disability scores were improved after 5 years for both men and women. The most prominent improvements occurred after 6 months, but less so thereafter. There were no significant differences between men and women with regard to individual changes at the 5-year follow-up concerning the pain intensity or disability scores. There were no significant differences, either for women or men, between low, median, or high intensity exercise groups regarding pain intensity or disability values for the individual change at the 5-year follow-up. CONCLUSIONS: Over a 5-year period, both men and women who had sought care for LBP reported a decrease in pain and disability; however, only a few were fully restored. In this study, we found no effect of nonspecific physical exercise on recovery from LBP in men and women.

Adult↗