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PubMed1990

Influence of acute physical exercise on glutathione and lipid peroxides in blood of rat and man.

In rats physical exercise (30 min running on a treadmill) lowered total glutathione, oxidized glutathione and lipid peroxide concentration in blood. In man (young healthy male volunteers, moderate to excellent physical condition) running (30 min) did not influence these parameters. It is concluded that by normal life and psychophysical vigilance the moderate oxidative stress could be compensated.

Adult↗
PubMed1997

Physical exercise, endogenous opioids and immune function.

The experimental data available today strongly indicate that various types of physiological stressors, including physical exercise and emotional stress, can influence immune function. Natural immunity represents a first line of defence in viral infections and cytotoxicity to a variety of tumour cells. Natural immunity is strongly influenced by chronic exercise and this regulation includes interaction between the nervous, endocrine and immune systems. Central mechanisms including the endogenous opioids are of great interest. Chronic activation of endogenous opioid systems augments natural cytotoxicity and the possible involvement the opioids in the exercise-induced enhancement of natural immunity is discussed. Also, catecholamines seem to play an important role in the regulation of immune function, both after chronic exercise and emotional stress. The physiological significance of the reported changes in natural cytotoxicity after exercise-training is as yet unclear.

Animals↗
PubMed1997

Effects of acute physical exercise on central serotonergic systems.

This paper reviews data concerning the effects of acute physical exercise (treadmill running) in trained rats. Works from the 1980's have established that acute running increases brain serotonin (5-hydroxytryptamine: 5-HT) synthesis in two ways. Lipolysis-elicited release of free fatty acids in the blood compartment displaces the binding of the essential amino acid tryptophan to albumin, thereby increasing the concentration of the so-called "free tryptophan" portion, and because exercise increases the ratio of circulating free tryptophan to the sum of the concentrations of the amino acids that compete with tryptophan for uptake at the blood-brain barrier level, tryptophan enters markedly in the brain compartment. However, this marked increase in central tryptophan levels increases only to a low extent brain 5-HT synthesis, as assessed by the analysis of 5-hydroxyindoleacetic acid levels, thereby suggesting that exercise promotes feedback regulatory mechanisms. Indirect indices of 5-HT functions open the possibility that acute exercise-induced increases in 5-HT biosynthesis are associated with (or lead to) increases in 5-HT release. Lastly, the hypothesis that training and/or acute exercise triggers changes in 5-HT receptors has been examined in several studies; actually, both positive and negative results have been reached. Taken together, all these data support the need for future studies on the functional effects of exercise on 5-HT, including those related to the hypothesis that the positive mood effects of exercise rely (partly or totally) on central serotonergic systems.

Affect↗
PubMed1990

Effect of physical exercise on cytokines and lymphocyte subpopulations in human peripheral blood.

To examine the effect of intensive physical exercise on interleukin 2 (IL-2), tumor necrosis factor alpha (TNF alpha) and lymphocyte subsets, eleven elite and well-conditioned runners were tested in relation to a five-kilometer race. IL-2 was significantly decreased (p less than 0.01) immediately after the exercise and significantly increased after 24 hours (p less than 0.05), compared to the pre-exercise values taken at steady state. TNF alpha was significantly increased after 2 hours (p less than 0.05), and returned to habitual values after 24 hours. In the steady state at rest, elevation of HLA-DR+ cells was observed in all runners compared with control subjects (p less than 0.05), indicating a persistent activation of lymphoid cells. In connection with exercise a significant increase in NK cells (CD16+) was observed (p less than 0.01). The T-helper/T-suppressor (CD4+/CD8+) ratio was significantly reduced in connection with physical activity (p less than 0.01). In seven runners the ratio was reduced to a value of less than one. This decrease was observed immediately after the exercise, followed by increased ratios 2 hours later (p less than 0.01), due to oppositely directed quantitative changes of the CD4+ and CD8+ cell populations. After 24 hours the ratios returned to habitual levels. Furthermore, we confirmed an increase in the total number of granulocytes in connection with exercise (p less than 0.01), and observed a decrease in absolute numbers of lymphocytes two hours after exercise (p less than 0.01). We emphasize the importance of obtaining information about physical activity within the previous 24 hours before measuring white blood cell parameters.

Adult↗
PubMed1975

Effect of physical exercise on internal carotid artery blood flow after arterial reconstruction.

The effect of physical exercise on internal carotid artery (ICA) blood flow in conscious man was studied with the aid of electromagnetic flowmetry. A flow probe was implanted on the ICA in 25 patients after reconstruction of the artery. ICA mean blood flow and brachial artery mean blood pressure were continuously monitored in supine (25 patients) and sitting (24 patients) position at rest, during 5-6 minutes exercise on a bicycle ergometer and at rest after exercise. Arterial carbon dioxide tension (PaCO2) was studied in 6/25 work tests in supine and 7/24 in sitting position. Cardiac output was measured at rest and during exercise in 10/25 patients in supine and 8/24 patients in sitting position. In the supine group, ICA flow increased significantly within 1 minute and reached a maximal flow 15% above control flow within 2 minutes after the onset of exercise. The ICA flow then gradually declined, but remained almost significantly elevated, 7.5% above control, on termination of exercise. At rest, after exercise, the ICA flow decreased almost significantly to a level of 5% below the control flow within 5 minutes. There was a significant PaCO2 increase of 2.6 mmHg during exercise and a highly significant increase (72%) in cardiac output during exercise. The ICA flow at rest, before exercise, was about 15% lower in the sitting group than in the supine group. It increased in average 11.5% with 2 minutes of exercise and then gradually diminished. At rest, after exercise, ICA flow decreased further to a level of 8% below control flow within 5 minutes. PaCO2 increased significantly in average 1.6 mmHg during exercise. Cardiac output increased highly significantly (85%) during exercise. The ICA flow changes obtained during exercise in the present study indicate the presence of a regulatory mechanism counteracting the increasing perfusion pressure, but it is unable to compensate the decreased perfusion pressure when the body position was altered from supine to sitting. The cerebral vascular bed in the present patient material seems to operate above and below the lower limit of its pressure range for an adequate autoregulation.

Adult↗
PubMed1998

Physical exercise, oxidative stress and muscle damage in racehorses.

Since it has been suggested that lipid peroxidation following free radical overproduction may be one of the causes of physical exercise-induced myopathies and hemolysis in horses, we looked for the possible relationships between these phenomena and muscle fiber damage. We use a homogeneous group of Maremmana stallions which, after a 3-month training period, underwent a series of physical exercises of increasing intensity. We determined the contents of malondialdehyde (MDA), one of the main lipid peroxidation end-products, and glutathione the substrate of one of the most important free radical scavenger enzymes. We also measured creatine phosphokinase and serum lactate dehydrogenase isoenzyme activities whose modification may be indicative of muscle fiber damage. The results obtained indicated that the physical exercise we adopted was able to modify both MDA and glutathione contents in blood. However, its effect on some LDH isoenzyme activities suggested possible damage to tissues other than muscle.

Animals↗
PubMed2024

Acute physical exercise and ambulatory blood pressure in resistant hypertension.

OBJECTIVES: The effects of acute physical exercise in patients with resistant hypertension remain largely unexplored compared with hypertensive patients in general. We assessed the short-term effects of acute moderate-intensity (MICE) and high-intensity interval exercise (HIIE) on the clinic (BP) and 24-h ambulatory blood pressure (ABP) of patients with resistant hypertension. METHODS: Using a crossover randomized controlled design, 10 participants (56&#x200a;&#xb1;&#x200a;7&#x200a;years) with resistant hypertension performed three experimental sessions: MICE, HIIE, and control. MICE consisted of continuous treadmill exercise at an intensity of 3-4 metabolic equivalents of energy (METs) until completing 3&#x200a;kcal/kg and was energy-matched to HIIE (which included six to eight intervals of 3&#x200a;min duration at 6-7 METs interspersed with 1.5-min rests at 3 METs). In the control session, participants remained seated for 50&#x200a;min. Flow-mediated vasodilation, autonomic nervous system balance (heart rate variability), exerkines [interleukin (IL)-6, IL-8, IL-15, vascular endothelial growth factor A, irisin, adiponectin, and angiopoietin] and 71 inflammatory-related proteins were also measured. RESULTS: Compared with baseline, HIIE and MICE reduced clinic SBP immediately ( P &#x200a;<&#x200a;0.001 for both) and 90&#x200a;min ( P &#x200a;=&#x200a;0.001 and P &#x200a;=&#x200a;0.041, respectively) postexercise. HIIE and MICE also reduced clinic DBP immediately postexercise ( P &#x200a;=&#x200a;0.003 and P &#x200a;=&#x200a;0.025). By contrast, no changes were found in the control session. On the other hand, no significant effects were noted for 24&#x200a;h ABP measures or for the rest of variables. CONCLUSION: Although in patients with resistant hypertension, acute aerobic exercise induces short-term reductions in clinic BP, this stimulus does not suffice to reduce 24&#x200a;h ABP or to impact on potential biological mechanisms.

Humans↗
PubMed1991

Effect of low blood glucose on plasma CRF, ACTH, and cortisol during prolonged physical exercise.

The effects of low blood glucose concentration during low-intensity prolonged physical exercise on the hypothalamus-pituitary-adrenocortical axis were investigated in healthy young men. In experiment 1, six subjects who had fasted for 14 h performed bicycle exercise at 50% of their maximal O2 uptake until exhaustion. At the end of the exercise, adrenocorticotropic hormone (ACTH) and cortisol increased significantly. However, this hormonal response was totally abolished when the same subjects exercised at the same intensity while blood glucose concentrations were maintained at the preexercise level. In experiment 2, in addition to ACTH and cortisol, the possible changes in plasma concentration of corticotropin-releasing factor (CRF) were investigated during exercise of the same intensity performed by six subjects. As suggested by a previous study (Tabata et al. Clin. Physiol. Oxf. 4: 299-307, 1984), when the blood glucose concentrations decreased to less than 3.3 mM, plasma concentrations of CRF, ACTH, and cortisol showed a significant increase. At exhaustion, further increases were observed in plasma CRF, ACTH, and cortisol concentrations. These results demonstrate that decreases in blood glucose concentration trigger the pituitary-adrenocortical axis to enhance secretion of ACTH and cortisol during low-intensity prolonged exercise in humans. The data also might suggest that this activation is due to increased concentration of CRF, which was shown to increase when blood glucose concentration decreased to a critical level of 3.3 mM.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Promoting physical exercise in breast cancer care.

This article is intended to promote awareness of physical exercise as a safe, advantageous and feasible intervention for a patient with breast cancer or recovering from it. The numerous and varied benefits of exercise and the implications for nursing practice in light of current research evidence are discussed.

Anxiety↗
PubMed1994

[Evaluation of the effectiveness of a physical exercise program in weight reduction].

OBJECTIVE: To evaluate the effectiveness of a programme of individualised physical exercise in reducing fat weight. DESIGN: A randomised preventive trial. SETTING: Health Centre. PATIENTS: Obese people of both sexes, between 32 and 67 years old and with a fat percentage of 20-45% (men)/25-50% (women), were selected at random from among chronic patients at the Centre, with the exclusion of patients with heart diseases and of others with pathologies which made the programme's completion difficult. Two samples, comparable in gender, age and fat percentage (n1=49, n2=47), were obtained. INTERVENTIONS: THE study lasted 6 months, with 3 evaluations. The Intervention Group (G1) was advised to walk: the frequency, length and intensity of the exercise was calculated individually with a computer programme. Measurements and main results. Weight, height and 4 cutaneous folds were measured in each evaluation, where the Index of corporal mass (ICM), fat percentage and fat weight (FW) were calculated. The programme's acceptance was assessed according to compliance and subjective improvement. In the last evaluation, the GI achieved a 2.9% average decrease in the ICM, with no appreciable changes in the CG (p < 0.001). The FW in the GI decreased by 18%, whereas in the GC it increased by 12% (p < 0.001). Sixteen patients of the GI (32.7%) succeeded in reducing their FW by more than 20%, as against one individual (2.1%) of the GC (p < 0.0001). In the GI, 93.9% noted improvement in their physical, and 75.5% in their mental, well-being. 67.3% stated that they exercised more than three days a week. CONCLUSIONS: An individually tailored and complete prescription of exercise facilitates and improves compliance, achieving greater decrease in fat weight.

Adult↗
PubMedDate not supplied

Apoptosis of skeletal and cardiac muscles and physical exercise.

Besides the well-known reciprocal influences of skeletal muscle and heart during and after physical exercise, a new perspective is emerging on the short- and long-term effects of exercise-induced damage, in particular the pathogenic role of inappropriate apoptosis in skeletal and cardiac muscle. Cells from multicellular organisms self-destruct when they are no longer needed, or have become damaged; they do this by activating a genetically controlled cell suicide machinery that leads to programmed cell death (PCD), or apoptosis. Apoptosis is a specific form of programmed cell death that plays an important role in development, growth regulation and disease. Skeletal muscles in adult animals are fully differentiated syncytial cells. Apoptosis, which is known to be present in tissues that modulate their cellular homeostasis under the influence of growth and/or hormonal factors, has been recently described in early stages of myocardial infarct, and in dystrophic skeletal muscle. The role and the cellular and molecular aspects of muscle cell death and apoptosis are far from clear, particularly following several types of muscle damage (genetic defects, exercise-induced damage, oxidative stress, etc.). It can be predicted that apoptosis plays a major role in regulating myoblast proliferation during muscle regeneration, and in the progression of dystrophinopathies. A particularly important area has recently developed concerning cardiac muscle and reperfusion injury after ischemia; in this case as well, a major role of apoptosis is emerging.

Adult↗
PubMed1981

[Different patterns of latent pulmonary hypertension under physical exercise and their clinical significance].

The investigations pointed out that responses of the pulmonary hemodynamic in patients with COLD on physical exercises are highly different from those in normal subjects. The findings of pulmonary circulation on pink puffers (type A) and blue bloaters (type B) are differing in a specific manner. The lowest capacity of load is observed in patients of type A. Patients with clinical signs of type B show under exercise conditions the ability to approach their physical load capacity rather to that of normal persons. The features of prognosis, therapy and rehabilitation in the different patterns of pulmonary heart disease are discussed.

Cardiac Volume↗
PubMed1996

[Effect of physical exercise in fibromyalgia].

The aim of the present study was to review and discuss the literature on exercise-induced pain and physical fitness training in patients with fibromyalgia. Normal muscle metabolism during exercise and no muscle damage after physical activity are reported from recent studies. However, no rise in blood noradrenaline concentration during exercise was found in fibromyalgia patients as compared with a many-folded rise in healthy subjects. Exercise has been used in the treatment of fibromyalgia. Training has shown little benefit as regards pain, but has improved the physical fitness of the patients. Since pain may be exacerbated by physical activity, many patients become physically inactive, with possible development of reduced physical fitness. In the long run, fibromyalgia patients who exercise report less symptoms than sedentary patients do. Thus, exercise should be aimed at preventing physical inactivity and improving the patients' physical fitness.

Exercise↗
PubMed2001

Effects of physical exercise on anxiety, depression, and sensitivity to stress: a unifying theory.

Until recently, claims for the psychological benefits of physical exercise have tended to precede supportive evidence. Acutely, emotional effects of exercise remain confusing, both positive and negative effects being reported. Results of cross-sectional and longitudinal studies are more consistent in indicating that aerobic exercise training has antidepressant and anxiolytic effects and protects against harmful consequences of stress. Details of each of these effects remain unclear. Antidepressant and anxiolytic effects have been demonstrated most clearly in subclinical disorder, and clinical applications remain to be exploited. Cross-sectional studies link exercise habits to protection from harmful effects of stress on physical and mental health, but causality is not clear. Nevertheless, the pattern of evidence suggests the theory that exercise training recruits a process which confers enduring resilience to stress. This view allows the effects of exercise to be understood in terms of existing psychobiological knowledge, and it can thereby provide the theoretical base that is needed to guide future research in this area. Clinically, exercise training continues to offer clinical psychologists a vehicle for nonspecific therapeutic social and psychological processes. It also offers a specific psychological treatment that may be particularly effective for patients for whom more conventional psychological interventions are less acceptable.

Anxiety↗
PubMed2004

[A survey on the relationship between tobacco use and physical exercise among university students].

OBJECTIVE: To determine the prevalence of tobacco use among university students who participate in sports activities. MATERIALS AND METHODS This was a descriptive, cross-sectional study based on a self-administered questionnaire completed by students who participated in activities at a university sports center. The variables studied were age, sex, tobacco use, cigarettes/day, prior history of physical exercise, awareness of the regulations concerning tobacco use in force on the university campus, opinion on the relationship between smoking and reduced physical performance, and desire to quit smoking. RESULTS: A total of 406 completed questionnaires were received (41.2% of the target population); 71.7% were from women and 28.3% from men. The mean (SD) age of the sample was 22 (3.6) years, and the prevalence of smoking was 30.3%. The mean number of cigarettes smoked per day was 10.5 (6.7) for the sample as a whole, 9.3 (6.1) for women, and 14.7 (7.4) for men; the differences were statistically significant. No significant differences were found with respect to the relationship between exercise and tobacco use. A total of 98.8% of the subjects were of the opinion that smoking reduced physical performance, and 46.3% expressed a desire to quit. CONCLUSIONS: The practice of physical exercise during adolescence as part of a prevention program might interfere with the factors that lead young people to start smoking and thereby contribute to a reduction in the prevalence of tobacco use in the population as a whole.

Adolescent↗
PubMed2001

Physical exercise and normobaric hypoxia: independent modulators of peripheral cholecystokinin metabolism in man.

The purpose of the present investigation was to determine the independent effects of hypoxia and physical exercise on peripheral cholecystokinin (CCK) metabolism in humans. Thirty-two physically active men were randomly assigned in a double-blind manner to either a normoxic (N; n = 14) or hypoxic (H; n = 18) group. During the acute study, subjects in the H group only participated in two tests, separated by 48 h, which involved a cycling test to exhaustion in normobaric normoxia and normobaric hypoxia (inspired O(2) fraction = 0.21 and 0.16, respectively). In the intermittent study, N and H groups cycle-trained for 4 wk at the same relative exercise intensity in both normoxia and hypoxia. Acute normoxic exercise consistently raised plasma CCK during both studies by 290-723%, which correlated with increases in the plasma ratio of free tryptophan to branched chain amino acids (r = 0.58-0.71, P < 0.05). In contrast, acute hypoxic exercise decreased CCK by 7.0 +/- 5.5 pmol/l, which correlated with the decrease in arterial oxygen saturation (r = 0.56, P < 0.05). In the intermittent study, plasma CCK response at rest and after normoxic exercise was not altered after physical training, despite a slight decrease in adiposity. We conclude that peripheral CCK metabolism 1) is more sensitive to acute changes than chronic changes in energy expenditure and 2) is potentially associated with acute changes in tissue PO(2) and metabolic precursors of cerebral serotoninergic activity.

Adult↗
PubMed1998

Physical exercise: a pillar for cancer prevention?

Both epidemiological and experimental studies have shown that physical exercise deserves particular attention in any consideration of approaches to the prevention of neoplasia, especially since it also exerts consistent beneficial effects on the other major chronic diseases prevalent in the Western world, atherosclerosis and non-insulin dependent diabetes mellitus (NIDDM). The organ sites for which strong evidence has been gained for a protective influence of exercise or an elevated risk with a sedentary existence include the colon, prostate, breast and endometrium. The underlying mechanisms appear to centre on the hormones insulin and oestrogen, serum elevation of both of these endocrine factors being associated with increased risk of neoplastic development. The immense potential benefit of an increased level of exercise in the general population suggests that commensurate measures should be taken in the field of cancer education.

Chronic Disease↗