PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Physical exercise”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources

Using social cognitive theory to explain discretionary, "leisure-time" physical exercise among high school students.

PURPOSE: To examine whether knowledge of high school students' actions of self-regulation, and perceptions of self-efficacy to overcome exercise barriers, social situation, and outcome expectation will predict non-school related moderate and vigorous physical exercise. METHODS: High school students enrolled in introductory Physical Education courses completed questionnaires that targeted selected Social Cognitive Theory variables. They also self-reported their typical "leisure-time" exercise participation using a standardized questionnaire. Bivariate correlation statistic and hierarchical regression were conducted on reports of moderate and vigorous exercise frequency. RESULTS: Each predictor variable was significantly associated with measures of moderate and vigorous exercise frequency. All predictor variables were significant in the final regression model used to explain vigorous exercise. After controlling for the effects of gender, the psychosocial variables explained 29% of variance in vigorous exercise frequency. Three of four predictor variables were significant in the final regression equation used to explain moderate exercise. The final regression equation accounted for 11% of variance in moderate exercise frequency. CONCLUSIONS: Professionals who attempt to increase the prevalence of physical exercise through educational methods should focus on the psychosocial variables utilized in this study.

Adolescent↗

Physical exercise and antioxidant defenses in the heart.

Cardiac muscle relies highly on aerobic metabolism. Heart muscle has a high oxygen uptake at resting conditions, which increases many fold during exhaustive physical exercise. Such a high rate of oxidative metabolism is often associated with enhanced production of reactive oxygen metabolites. A single bout of strenuous exercise has been demonstrated to induce oxidative damage in heart. Such oxidant insult may lead to adaptive responses and strengthen antioxidant defenses in the heart tissue. Endurance exercise training has indeed been shown to upregulate heart tissue antioxidant defenses. Recently, we have observed that even predominantly anaerobic sprint training regimens may enhance cardiac antioxidant defenses. Regular physical exercise may beneficially influence cardiac antioxidant defenses and promote overall cardiac function.

Animals↗

Role of GABA and opioids in the regulation of the vasopressin response to physical exercise in normal men.

The present study was undertaken in order to establish the possible involvement of GABAergic and/or opioid pathways in the mechanism underlying the arginine-vasopressin (AVP) response to physical exercise. After fasting overnight, seven subjects were tested on four mornings at least 1 week apart. Exercise was performed on a bicycle ergometer. The workload was gradually increased at 3 min intervals until exhaustion and lasted about 15 min in all subjects. Tests were carried out under administration of placebo, the opioid antagonist naloxone (10 mg as an i.v. bolus injection), the GABAergic agonist sodium valproate (600 mg in three divided doses orally) or naloxone plus sodium valproate. Plasma AVP levels rose 4-fold during exercise. The administration of naloxone did not modify, whereas sodium valproate completely abolished the plasma AVP rise during exercise. When naloxone was given together with sodium valproate, AVP rose 3-fold in response to exercise. These data suggest the involvement of a GABAergic mechanism in regulation of the AVP response to physical exercise in men. Furthermore, the data argue against a role of naloxone sensitive endogenous opioids in the control of AVP during exercise, whereas they suggest a partial opioid mediation of the GABAergic inhibitory action.

Adult↗

[Stimulation of growth hormone (HGH) secretion by physical exercise (author's transl)].

Authors study forty eight children with severe lineal growth retardation. The more frequent causes of a stunted growth were ruled out previously (systemic and chronic diseases, metabolic disorders, genetic alterations, etc.). As a screening test, physical exercise was used to detect growth hormone (HGH) deficiency. A normal response was considered when HGH levels rose more than 7,0 ng./ml. after 20 minutes of continuous exercise. In those cases in which this level was not attained. insulin-hypoglycemia alone and followed by insulin plus an arginine infusion were used as stimuli, to confirm the lack of HGH response. A correct response to the exercise was found in 81% of the cases. It is concluded that the physical exercise as HGH stimulus is a good screening test. It presents a high degree of confidence with some other qualities, mainly: little disturbances to the patients, a rapid performance, lack of unpleasant colateral effects, and the possibility that it can be carried out by sanitary non-medical personnel.

Child↗

Inhibition of platelet aggregability by moderate-intensity physical exercise: a randomized clinical trial in overweight men.

It has been postulated that platelet function plays an important role in the initiation of atherosclerosis. Currently there are no definitive data on the longer-term effects of regular physical exercise on platelet function in humans. We assessed the influence of regular moderate-intensity physical exercise (brisk walking to slow jogging) on platelet aggregation in a population-based sample of middle-aged, overweight, mildly hypertensive men in eastern Finland. In this controlled study, we evaluated the net effect of exercise on platelet aggregation by studying changes in optical density and ATP release in platelet-rich plasma. A significant inhibition of secondary platelet aggregation from 27% to 36% was observed in the men taking regular exercise. These findings give new insight into the possible protective effects of exercise against the risk of ischemic heart disease.

Adenosine Triphosphate↗

Cystic fibrosis: physical exercise versus chest physiotherapy.

Twelve children with cystic fibrosis were admitted to a paediatric rehabilitation hospital for 17 days to take part in a training programme of vigorous physical exercise and sport. The daily inhalation-physiotherapy routine was stopped. Ventilatory status was assessed by spirometry and measurement of lung volumes one day before admission, one day after the end of the hospital stay, and 8 weeks later. Flow measurements of forced expiration had improved appreciably by the end of the course, but most of them returned to pretraining levels 8 weeks later. Lung volumes did not change significantly. Daily recordings of peak flow indicated improvement of airways function plus some ventilatory muscle training. Regular physical exercise could replace the inhalation-physiotherapy routine in some children with cystic fibrosis.

Adolescent↗

Levels of complement receptor type one (CR1, CD35) on erythrocytes, circulating immune complexes and complement C3 split products C3d and C3c are not changed by short-term physical exercise or training.

The effect of heavy short-term physical exercise on the levels of complement receptor type one (CR1, CD35) on erythrocytes, the concentrations of circulating immune complexes (IC), and the complement C3 split products C3c and C3d were examined in young healthy males. Fourteen untrained volunteers underwent a 60-min bicycle exercise test at 75% of maximal oxygen uptake (VO2max). Six of the volunteers were exercised twice with an interval of at least one month. Before the second bicycle test they received oral indomethacin. With an interval of at least 1 week, 6 also went through a 60-min back-muscle exercise at up to 30% of VO2max. Blood samples were collected before and during the last few minutes of exercise as well as 2 h and 24 h afterwards. The same parameters were examined once in 29 highly trained racing cyclists. There were no consistent or significant exercise-induced changes in the levels of erythrocyte CR1, circulating IC, C3c nor C3d as measured by an enzyme-linked immunosorbent assay, polyethylene glycol precipitation complement consumption method, and by intermediate gel rocket immunoelectrophoresis, respectively. Neither did these parameters differ from controls in the highly trained group. The results indicate that CR1 on erythrocytes, circulating immune complexes and complement cleavage products C3c and C3d in healthy subjects remain unaffected by short-term heavy physical activity and training.

Adult↗

Glucose metabolism and catecholamine responses during physical exercise in non-insulin-dependent diabetes.

Blood glucose, lactate, insulin, C-peptide, norepinephrine and epinephrine concentrations were determined in non-insulin-dependent diabetic patients and in healthy controls before, during and after moderate exercise, to evaluate the effects of physical exercise on glucoregulation. Ten diabetic and ten healthy control females bicycled 14 minutes at 60% of their maximal heart rates. In the diabetic patients, there were no significant changes in blood glucose levels post-exercise, while in controls the 60 minute post-exercise levels were higher than those measured in mid-exercise (p < 0.05). Lactate concentrations increased with exercise in both groups in a similar manner, with highest values at the end of exercise. No significant changes in insulin and C-peptide levels were induced with exercise in either group. Norepinephrine and epinephrine concentrations increased 2.5-3 fold with exercise in both groups (p < 0.05 for all values) but in the diabetics an earlier and prolonged catecholamine response was observed. We propose that catecholamines prevent hypoglycaemia during exercise when changes in insulin and C-peptide do not occur. In diabetic patients with good metabolic control, the glucoregulatory response to exercise is not worse than in anthropometrically similar controls with similar levels of fitness.

Blood Glucose↗

Mucus clearance with three chest physiotherapy regimes in cystic fibrosis: a comparison between postural drainage, PEP and physical exercise.

The effects of three different regimes of chest physiotherapy were compared in this cross-over study. Mucus clearance was monitored in nine clinically stable cystic fibrosis (CF) patients. The patients performed: 1) postural drainage with thoracic expansion exercises + forced expiration technique (FET) in the left decubitus position; 2) positive expiratory pressure (PEP)-mask breathing + FET; and 3) physical exercise on a bicycle ergometer + FET. All treatments had the same duration and FET was standardized. Mucus clearance was assessed using a technique based on measurement of the elimination of inhaled radiolabelled particles. Mean clearance of tracer from the right lung by postural drainage, PEP and physical exercise was 18% (range 10-29%), 20% (12-43%), 16% (8-25%), respectively, and from the left lung 20% (8-42%), 15% (5-23%) and 13% (5-17%), respectively. The differences were not statistically significant. Surprisingly, postural drainage (PD) was the most effective technique in the left, dependent lung in 7 of the 9 patients.

Adult↗

The response of the ageing heart to regular physical exercise. An echo and Doppler study.

In upper middle age healthy subjects the functional cardiac reserve is known to be decreased (Port et al., 1980; Aubert et al., 1994). On the other hand regular physical exercise improves the cardiovascular function (Nishimura et al., 1980). The aim of this study was to establish whether regular physical exercise is associated with a significant change in the ageing process of the cardiovascular system.

Aging↗

Contribution of tonic vagal modulation of heart rate, central respiratory drive, respiratory depth, and respiratory frequency to respiratory sinus arrhythmia during mental stress and physical exercise.

This study tested various sources of changes in respiratory sinus arrhythmia (RSA). Twenty-two healthy participants participated in three experimental conditions (mental stress, relaxation, and mild physical exercise) that each consisted of three breathing parts (normal breathing, breathing compressed room air, and breathing compressed 5% CO2-enriched air). Independent contributions to changes in RSA were found for changes in tonic vagal modulation of heart rate, central respiratory drive (i.e., PaCO2), respiratory depth, and respiratory frequency. The relative contributions to changes in RSA differed for mental stress and physical exercise. It is concluded that uncorrected RSA will suffice to index within-subject changes in tonic vagal modulation of heart rate in most situations. However, if the central respiratory drive is expected to change, RSA should ideally be corrected for changes in PaCO2, respiratory depth, and respiratory frequency.

Adult↗

Activation of leukocytes during prolonged physical exercise.

Previous studies have demonstrated an increment of circulating leukocytes and enhanced secretion of interleukin-1 by monocytes and macrophages during physical exercise. In the present study the effect of physical exertion on the activity of polymorphonuclear (PMN) leukocytes was investigated. Following both short-term (running 2,000 meters) and long-term (running 10,000 meters) exertion, phorbol-stimulated chemiluminescence, as an indicator of leukocytic oxygen radical formation and release of leukocytic elastase, as a parameter of degranulation, were determined immediately after running. The number of circulating leukocytes increased both after short-term (+21%) and long-term (+61%) exercise. There was a minor release of PMN elastase following short-term activity causing plasma levels of this compound to rise from 100 +/- 4.0 ng/ml to 116 +/- 12.3 ng/ml. Long-term exercise, on the other hand, induced a significant increase of elastase plasma levels from 107 +/- 9.1 ng/ml to 300 +/- 23.4 ng/ml, suggesting a remarkable release of this proteinase from neutrophils. Based on these findings we conclude that during physical exercise degranulation of PMN leukocytes occurs. Moreover, the fact that phorbol-stimulated chemiluminescence is decreased after running demonstrates an impaired capability of white cells to generate oxygen radicals.

Adult↗

Effects of smoking and physical exercise on platelet free cytosolic calcium in healthy normotensive volunteers.

Platelet free cytosolic calcium (PFCC) was measured in 21 healthy volunteers before and after cigarette smoking or physical exercise. The aim was to investigate whether acute blood pressure changes and increases in circulating levels of catecholamines and vasopressin modify PFCC. PFCC was determined using the Quin-2 method. Following cigarette smoking, significant increases in blood pressure, heart rate, plasma epinephrine (35 +/- 18 pg/ml before versus 51 +/- 31 pg/ml after smoking, P less than 0.05, mean +/- s.d.) and vasopressin levels (0.8 +/- 0.3 pg/ml before and 4.2 +/- 4.1 pg/ml after smoking, P less than 0.001) were observed. However, despite these acute hormonal and hemodynamic changes, PFCC remained stable at 156 +/- 55 nmol/l prior to the study and 157 +/- 29 nmol/l and 156 +/- 38 nmol/l at 20 and 80 min post-smoking, respectively. Acute physical exercise led to an increase in heart rate and systolic blood pressure but to a decrease in diastolic pressure. Moreover, a marked increase in plasma norepinephrine levels was observed after exercise (213 +/- 71 pg/ml before versus 747 +/- 501 pg/ml after exercise, P +/- 0.001). Again, PFCC was stable at 185 +/- 56 nmol/l at baseline versus 188 +/- 51 nmol/l at 20 min and 155 +/- 26 nmol/l at 80 min after exercise. These results therefore demonstrate that PFCC is not influenced acutely either by blood pressure increases, or by elevations in circulating catecholamine and vasopressin concentrations.

Adult↗

Status of physical exercise and its association with obesity and hypertension in two urban assembly constituencies of East Delhi.

In a community based study using systematic random sampling in two urban Assembly constituencies in East Delhi, 420 subjects above the age of 30 years were interviewed to find out their status regarding physical exercise. People doing regular exercise were found to be only 44.8%. The commonest reason associated for not doing/irregular physical exercise was nonavailability of time (63.3%), followed by no need felt by the respondents to exercise (23.3%). The prevalence of obesity in the group doing regular exercise was much lower than the group that was not doing regular exercise and the results were statistically significant. Though a similar association was found with hypertension also, the results were not statistically significant.

Adult↗

Longevity of men capable of prolonged vigorous physical exercise: a 32 year follow up of 2259 participants in the Dutch eleven cities ice skating tour.

OBJECTIVE: To compare the long term survival of a group of athletes taking prolonged vigorous physical exercise to that of the general population. DESIGN: Follow up of a cohort of participants in the Dutch eleven cities ice skating tour (a race and recreational tour) over a distance of 200 kilometers. SETTING: Data on participation from the organising committee and data on mortality from all municipalities in The Netherlands. SUBJECTS: 2259 Male athletes. MAIN OUTCOME MEASURES: Comparison of all cause mortality in male participants in the tour with that in the general population of The Netherlands. RESULTS: The standardised mortality ratio for all participants during 32 years of follow up was 0.76 (95% confidence interval 0.68 to 0.85), and 0.90 (0.48 to 1.44) for participants in the race, and 0.72 (0.60 to 0.86) for participants in the recreational tour who finished within the time limit. CONCLUSIONS: The capacity for prolonged and vigorous physical exercise, particularly if the exercise is recreational, is a strong indicator of longevity.

Adult↗

Plasma renin activity, aldosterone and cortisol levels during physical exercise in essential hypertension.

Plasma renin activity, aldosterone and cortisol levels, as well as renal blood flow were studied in borderline and established hypertensive patients and in healthy control subjects at rest and following graded dynamic upright exercise. Resting plasma renin activity was elevated in established hypertension, renal blood flow at rest was decreased in patients with borderline hypertension but its per cent decrease during exercise was similar in all groups. Following exercise, plasma renin activity increased in all groups but a step-wise increase with graded exercise occurred only in borderline hypertension. Resting plasma aldosterone and cortisol levels were similar in all groups. In the hypertension patients physical exercise was associated with disproportional changes of plasma renin activity and aldosterone levels. Plasma cortisol displayed patterns which were roughly similar to those or aldosterone in the control group an in established hypertension, but not in the borderline group, where the most pronounced increased of aldosterone level was associated with the lowest level of cortisol. It is concluded that the physiological response of the renin-angiotensin-aldosterone system to physical exercise is altered in essential hypertension.

Adult↗

[Evaluation of physical exercise and fatigue sensation by CFSI (Cumulative Fatigue Symptoms Index)].

Cumulative Fatigue Symptoms Index (CFSI) is used for workers' subjective assessment of feeling of fatigue and of symptoms. Until now, this index has been used in the analysis of members of the same occupation. The purpose of this study is to examine fatigue symptoms in workers and to assess by CFSI the effect of regular physical exercise. Study participants were an exercise group (n = 67) and a non-exercise group (n = 115) of older workers, aged from 30 to 69 years. The CFSI questionnaire was distributed to all participants and the former group (exercise) answered two descriptive questions concerning the aim and subjective effects of physical exercise. As a result, it was found that mental fatigue symptoms decreased in the exercise group even after considering the differences in managerial position, subjective senses on health and marital status which are related to degree of feelings of fatigue. Weakened vitality was significantly less in the exercise group than the non-exercise group. Therefore, we concluded that weakened vitality would be needed to be regarded on an assessment scale for effects caused by exercise. It has also been considered that we should investigate general fatigue in assessing physical fatigue relating to one's lifestyle.

Adult↗

Action plans and coping plans for physical exercise: A longitudinal intervention study in cardiac rehabilitation.

OBJECTIVES: The aim of the present study was to test two brief planning interventions designed to encourage cardiac patients to engage in regular physical exercise following discharge from rehabilitation. The interventions comprised action plans on (a) when, where, and how to act, and (b) coping plans on how to deal with anticipated barriers. DESIGN AND METHOD: An experimental longitudinal trial was conducted to test two interventions that either focused on action planning alone, or on a combination of action planning and coping planning. A total of 211 participants completed assessments at baseline and 2 months after discharge. Participants were randomly assigned to either one of the intervention groups or a standard-care control group. RESULTS: Participants in the combined planning group did significantly more physical exercise 2 months post-discharge than those in the other groups. CONCLUSIONS: The theoretical distinction between action planning and coping planning as introduced in the present study has proven useful in explaining changes in health-related behaviour. The combined planning intervention can be applied in the context of cardiac rehabilitation programmes.

Adaptation, Psychological↗