Effects Of Moderate Exercise Research Articles

Decision Making in Elite White-Water Athletes Paddling on a Kayak Ergometer

The present study investigated the effects of acute paddling on performance in a typical decision-making task. It was aimed at assessing whether the effects of moderate exercise can be replicated using the feet as response effectors when physical exercise essentially solicits upper-body muscles. Twelve national-level paddling athletes performed a Simon task while paddling at a moderate (75% of maximal heart rate, HRmax) and at very light (40% of HR(max)) intensities. The results showed that the effects of moderate exercise can be generalized to exercises involving different response effectors and upper-body muscle groups. They suggest (1) that the activation-suppression hypothesis (Ridderinkhof, 2002) holds when the task is performed with the feet, and (2) that moderate exercise speeds up reaction time and impairs the suppression of direct response activation.

The effect of moderate exercise on growth and aggression depending on social rank in groups of Arctic charr ( Salvelinus alpinus L.)

Several studies have shown that prolonged moderate exercise improve conditions for the farming of salmonids, by reducing aggressive interactions and resulting in enhanced growth and reduced size variation. The present study focuses on the effect of forced moderate exercise on growth and aggression depending on the individual social rank, compared to non-exercised controls in groups of Arctic charr ( Salvelinus alpinus L.). Social screening was done prior to the trial in each of 24 groups with five charr, where every fish was ranked into one of five social ranks by successive removal of individuals displaying a dominant or aggressive behaviour. Four ranking groups (= 20 fish) were then merged into one experimental group (= 6 groups), each with four tagged individuals of ranks 1–5. After 62 days with or without forced exercise, no significant difference in mean Daily Growth Coefficient (DGC) in the exercised (DGC = 1.25 ± 0.46) and non-exercised (DGC = 1.39 ± 0.47) groups were found. A significant relationship between rank and size at the start remained significant in the non-exercised groups but became insignificant in the exercised groups. It was the highest ranked fish that gained by not being forced to exercise. They had a significantly higher weight gain than the highest ranked fish in the exercised groups and all lower ranked fish independent of treatment. The observed aggression was significantly higher in the non-exercised groups and higher in between than during feeding sessions.

Effects of moderate exercise on the kinetics of triglyceride-rich lipoproteins in overweight/obese middle-aged men

Prior moderate exercise reduces plasma triglycerides (TG), mainly in the large very low-density lipoprotein (VLDL1) fraction, but the mechanism is unclear. We investigated the effects of brisk walking on VLDL1-TG and -apolipoprotein (apo) B kinetics using a novel ‘Intralipid (IL) method’ [Al-Shayji et al. J. Lipid Res. 2007;48:2086–95]. Twelve men, aged 44.0±8.4 years and BMI 31.3±5.1kgm−2 (mean±S.D.), each underwent two IL infusion tests in random order. Subjects were given a bolus IL dose of 0.1gkg−1 body mass, followed by 75-min IL infusion of 0.1gkg−1h−1.

Effect of l-arginine on circulating endothelial progenitor cells and VEGF after moderate physical training in mice

Alteration of levels and functional activities of circulating endothelial progenitor cells (EPCs) induced by risk factors for coronary heart disease (CHD) profoundly influence their role in the regeneration of tissue ischemia and angiogenesis. Among antioxidant nutrients in the prevention of CHD, l-arginine is particularly effective in enhancing the protection afforded by moderate physical exercise. Here, we aimed to evaluate the effects of l-arginine on EPC levels in C57BL/6J mice subjected to moderate physical exercise. Results showed that supplementation with l-arginine potentiates the effects of moderate physical exercise by increasing significantly EPCs ( P < 0.001) and VEGF serum levels ( P < 0.001). Our report highlights the beneficial effect of l-arginine in the modulation of EPC levels and VEGF secretion.

Exercise intensity: Platelet function and platelet–leukocyte conjugate formation in untrained subjects

Strenuous and exhaustive exercise intensifies platelet activity as shown in the literature but effects of moderate exercise are still in discussion. The present study investigated effects of two different standardised exercise intensities controlled by individual anaerobic threshold (IAT) on platelet function and conjugate formation. 20 healthy male non-smokers underwent two exercises at 80% (moderate) of IAT which corresponded to about 57% of peak oxygen consumption (peak VO(2)) in our subjects and 100% (strenuous) of IAT, corresponding to about 69% peak VO(2). Blood samples were taken after 30 min rest and immediately after exercise. CD62P expression and differentiated platelet-leukocyte conjugates (CD45, CD14, CD41) as well as microparticles and platelet-platelet aggregates were detected flow cytometrically with and without TRAP-6-stimulation. CD62P expression and the number of aggregates were increased (P< or =0.05) after exercise in the TRAP-stimulation experiment independent of exercise intensity. The number of platelet-granulocyte (rest 5.7+/-1.8 to post 8.1+/-1.7 (80%) vs. 6.2+/-1.9 to 10.3+/-2.0 (100%)), platelet-monocyte (5.3+/-3.6 to 8.5+/-3.7 (80%) vs. 7.4+/-3.5 to 11.7+/-4.8 (100%)), and platelet-lymphocyte conjugates (4.4+/-1.2 to 6.4+/-1.3 (80%) vs. 4.6+/-1.7 to 7.8+/-1.8% positive cells (100%)) were also higher after both exercises but increased significantly weaker (P< or =0.05) after moderate exercise. These results were confirmed by the TRAP-stimulation experiment. Although moderate exercise led to an increase in platelet reactivity and platelet-leukocyte conjugate formation the changes in conjugate formation were significantly weaker compared to strenuous exercise. Therefore it is recommended that submaximal endurance performance should be individually developed in order for everyone to be able to carry out normal daily activities and also to exercise well below the IAT.

Positive Effects of Moderate Exercise on Glycosaminoglycan Content in Knee Cartilage: A Four-Month, Randomized, Controlled Trial in Patients at Risk of Osteoarthritis

Positive Effects of Moderate Exercise on Glycosaminoglycan Content in Knee Cartilage: A Four-Month, Randomized, Controlled Trial in Patients at Risk of Osteoarthritis

Effects of Moderate Exercise and Circadian Rhythms on Human Memory

The effects of exercise and circadian rhythms on memory function were explored in a group of shift workers (mean age 32 yrs). A variant of the Auditory-Verbal Learning Test was used to test memory for word lists at 9:30 a.m. and 12:30, 3:30, and 6:30 p.m. in a repeated-measures design. Without exercise there was clear evidence of a circadian rhythm in memory performance, with peak performance occurring at 12:30 and poorest performance at 3:30. A brisk 10-min walk followed by a 15- to 30-min recovery period resulted in significant improvement in memory recall at all time periods except 12:30. The results of the AVLT task suggest an improvement in both working memory and long-term memory performance. Rhythmic changes in serotonin, epinephrine, norepinephrine, and acetylcholine levels all affect cortical arousal and cognitive function. Exercise may have resulted in altered levels of these neurotransmitters, increased glucose, oxygen, or nutrient levels, or from temporary changes in growth hormone or brain-derived neurotropic factor levels resulting in increased synaptogenesis and neurogenesis. The physiological basis of this temporary improvement in memory remains to be determined, but this simple behavioral intervention may have widespread application in improving memory function in all sections of the population including children and the elderly.

Effect of moderate physical exercise on plasma and tissue levels of insulin-like growth factor–1 in adult rats

The aim of the present study was to evaluate the influence of moderate physical exercise on muscle, liver, and plasma insulin-like growth factor–1 (IGF-1) levels and to analyze certain protein and carbohydrate metabolism patterns related to this physiological state. Adult male rats were subjected to physical exercise consisting of swimming for a period of 6 weeks. The animals were divided into two groups, a trained (T) and a sedentary (S) group, with both groups receiving a 12% casein diet. The following parameters were analyzed: body weight, food intake, muscle and liver weight, plasma IGF-1, glucose, insulin, urea and creatinine, muscle protein, glycogen, and muscle and liver IGF-1. Group T showed lower body weight, food intake, and glucose and insulin levels than group S. The other parameters did not differ between groups. These results suggest that moderate physical exercise does not alter IGF-1 levels and therefore cannot be considered a regulating factor of IGF-1 under these experimental conditions.

Effect of moderate physical exercise on plasma and tissue levels of insulin-like growth factor–1 in adult rats

The aim of the present study was to evaluate the influence of moderate physical exercise on muscle, liver, and plasma insulin-like growth factor–1 (IGF-1) levels and to analyze certain protein and carbohydrate metabolism patterns related to this physiological state. Adult male rats were subjected to physical exercise consisting of swimming for a period of 6 weeks. The animals were divided into two groups, a trained (T) and a sedentary (S) group, with both groups receiving a 12% casein diet. The following parameters were analyzed: body weight, food intake, muscle and liver weight, plasma IGF-1, glucose, insulin, urea and creatinine, muscle protein, glycogen, and muscle and liver IGF-1. Group T showed lower body weight, food intake, and glucose and insulin levels than group S. The other parameters did not differ between groups. These results suggest that moderate physical exercise does not alter IGF-1 levels and therefore cannot be considered a regulating factor of IGF-1 under these experimental conditions.

Facilitating effects of exercise on information processing

The aim of this study was to examine the facilitating effects of moderate physical exercise on the reaction process to gain a better understanding of the interaction between physiological and cognitive processes. Sixteen participants with specific expertise in decision-making sports performed a double task consisting of choice reaction time while cycling. Signal quality, stimulus–response compatibility and time uncertainty were manipulated. Participants were tested at rest and while cycling at 20% and at 50% of their maximal aerobic power. A mood assessment questionnaire and a critical flicker fusion test were administered before and after the choice reaction time task. The results showed that moderate-intensity exercise (50% maximal aerobic power) improves cognitive performance and that low-intensity exercise (20% maximal aerobic power) enables participants to compensate the negative dual-task effect.

Effects of Moderate Exercise on Susceptibility to Respiratory Infection in Aged Mice

Effects of Moderate Exercise on Susceptibility to Respiratory Infection in Aged Mice

Effect of sub-elite competitive running on bone density, body composition and sexual maturity of adolescent females.

The attainment of optimal peak bone mass during adolescence is important in the primary prevention of osteoporosis. Exercise may contribute to skeletal development and bone density during growth, although competitive exercise is suggested to have an adverse effect. This study assesses the effect of moderate exercise on the bone density of adolescent females. Additionally, other factors which significantly influence attainment of peak bone mass were identified. This was a cross-sectional study of 42 adolescent females, classified as runners (n=15) or non-runners (n=27). Nutrient intake, energy expenditure, menstrual history and pubertal stage were recorded. Bone age, skinfold thickness, body composition and bone mineral density (BMD) of total body, lumbar spine and proximal femur were measured. Statistical analyses used Student's t-test, Pearson correlation and multiple regression analyses. Runners had lower fat mass and higher lean mass, with a trend to higher BMD in all sites measured. There were no significant differences in menstrual cycle regularity, age at menarche or number who had attained menarche. Pubic hair development was similar in both groups. Breast development was delayed in runners, although this may have been a function of lower fat mass in this group. When subjects were categorized according to menarchal status, postmenarchal girls were significantly taller and heavier, with higher fat mass and significantly higher total body and lumbar spine BMD. There was no significant relationship between BMD at any site and dietary nutrient intake. Multiple regression analyses, using BMD as the dependent variable, identified running status, pubertal stage, fat mass and lean mass as significant determinants. When BMD/height was used, significant determinants in total body BMD were fat mass, pubertal stage and running status, while in the lumbar spine, only the latter two variables remained significant. In conclusion, body composition, physical activity and sexual maturity were identified as significant determinants of bone density during adolescence. Runners had significantly lower body fat than non-runners, but this did not interfere with hormonal cyclicity, and caused no detriment to their bone density. The results of this study are reassuring, since they indicate that sub-elite competitive athletics has no detrimental effect on bone mass accrual in adolescent females.

Effect of exercise on immunologic factors in breast milk.

Although it is well documented that breast milk provides optimal nutrition and immune benefits to the infant, factors that influence the immunologic composition of breast milk are less understood. A recent study reported that immunoglobulin A (IgA) levels in breast milk are lower after exercise compared with resting concentrations. However, the women exercised until exhaustion. The effect of moderate exercise on immunologic components in breast milk has not been reported. Therefore, the purpose of this study was to 1) compare the levels of immunologic compounds in breast milk of exercising women with the milk of sedentary women and 2) determine whether 30 minutes of moderate exercise affects immunologic properties of breast milk. Exclusively lactating women were studied at 3 months' postpartum. Women in the exercise group (EG; n = 29) reported exercising aerobically at least 30 minutes/d for 3 days/wk, and women in the sedentary group (SG; n = 24) had exercised once a week or less during the previous 6 weeks. Cardiovascular fitness levels and concentrations of IgA, lactoferrin, and lysozyme in milk were measured. A subsample of the EG (n = 17) participated in a 30-minute exercise session at 75% of maximum heart rate and a rest session of 30 minutes of sitting rest on 2 separate days. Breast milk samples were collected before and 10 and 60 minutes after exercise and rest sessions. IgA, lactoferrin, and lysozyme concentrations were measured. Women in the EG had a higher level of cardiovascular fitness than women in the SG (39.7 +/- 1.0 vs 32.4 +/- 1.0 mL O(2)/kg/min). Milk concentrations of IgA, lactoferrin, or lysozyme were not significantly different between groups. In addition, there were no significant differences in the concentrations of IgA, lactoferrin, or lysozyme after moderate exercise compared with sitting rest. Moderate exercise during lactation improves cardiovascular fitness without affecting levels of IgA, lactoferrin, or lysozyme in breast milk.

Effects of moderate exercise on metabolic responses and respiratory exchange ratio (RER).

To counteract insulin resistance, it is necessary to increase the utilization rate of fatty acids in blood and adipose tissue. The aim of the present study was to determine the relation between metabolic responses and exercise duration from changes in the respiratory exchange ratio (RER). The mean RER during 30 minutes of moderate exercise (mean pulse 115 beats/min) was 0.89 +/- 0.02, indicating no major change. Significant changes were observed in the levels of plasma glucose (PG), plasma free fatty acid (FFA), and plasma immunoreactive insulin (IRI) before and after exercise, demonstrating a decrease in PG and IRI, and an increase in FFA levels. However, the RER value indicated that carbohydrate was the dominant metabolic substrate; therefore, prolonged or repetitive brief and mild to moderate exercise is necessary to increase the utilization of fatty acids.

Effect of moderate exercise on immune senescence in men.

The purpose of this study was to examine the relationship between active compared to inactive lifestyles and immunocompetence in men. Subjects, all male volunteers, regularly exercising moderately were separated into three age groups: young (20-39 years), middle-aged (40-59 years) and elderly (more than 60 years). Age-matched sedentary male subjects served as controls in each group. Immunological assessments were, total leucocyte count, lymphocyte subpopulation counts, natural killer cell activity and neutrophilic phagocytosis. Total leucocyte and T-cell (CD3+) counts were not significantly different among the groups. Among T-cell subsets, there was a slight increase in helper T-cell (CD3+CD4+) and a decrease in cytotoxic/suppressor T-cell (CD3+CD8+) concentrations in the older sedentary subjects, resulting in an age-associated significant increase in the CD4:CD8 ratio among those control groups. However, among the exerciser groups, no such increase and decrease in the T-cell subpopulations or an age-related increase of the CD4:CD8 ratio were observed. Considering the components of innate immunity, the concentration of NK-cells (CD16+CD56+) significantly increased in the elderly exercisers, compared to that of the age-matched control subjects, or of the young group. The phagocytotic activity of neutrophils showed an age-associated decline, but of lesser degree in the elderly exercisers than in the elderly controls. Taken together, these results suggest that habitual and moderate training in later life is associated with a lesser age-related decline in certain aspects of circulating T-cell function and innate immunity.

有機酸の嗜好性に及ぼす中等度運動の影響

有機酸の嗜好性に及ぼす中等度運動の影響

Effect of moderate physical exercise on noninvasive cardiac autonomic tests in healthy volunteers

Background: In addition to the assessment of extreme cardiovascular reserve, new methodology is needed which is sensitive enough to detect subtle improvement in cardiovascular fitness in cardiac patients. Aim: This study modelled subtle clinical improvement by a moderate physical activity programme in healthy volunteers and investigated whether the improved fitness is detectable by non-invasive tests of cardiac autonomic status. Methods: Twenty healthy volunteers (ten women, mean age 39.6±7.8 years) were divided into two groups of five women and five men in each. One group (the active group) was subjected to a moderate physical training programme for 6 months. The other group (the passive group) served as controls and continued with a predominantly sedentary lifestyle. Twice before commencing the exercise programme and regularly afterwards, subjects were investigated by a series of non-invasive autonomic tests including controlled respiration, active postural change, isometric handgrip, and Valsalva manoeuvre. A continuous three lead semi-orthogonal electrocardiogram and continuous blood pressure monitoring was obtained. Statistical descriptors of heart rate and blood pressure, spectral descriptors of their modulation, and baroreflex index giving the proportion between simultaneous heart rate and blood pressure changes were obtained from each test. Results: Although the exercise programme was not extensive enough to be detected in changes of the baseline heart rate, the minimum RR interval during the Valsalva manoeuvre prolonged significantly with exercise in the active group. The mean arterial diastolic pressure decreased significantly. High frequency components of RR interval modulations decreased in supine controlled respiration and increased in standing controlled respiration and a trend towards an increase of both high frequency and low frequency components of diastolic arterial pressure modulations was noted with exercise. Baroreflex index assessed from Valsalva manoeuvre increased significantly. Conclusion: The study suggests that a selected set of non-invasive autonomic tests is sensitive enough to depict moderate improvement in cardiovascular fitness and that a multivariate assessment of cardiovascular fitness based on these tests might be applicable to monitoring chronic cardiac patients subjected to different clinical management modes.

Effects of moderate exercise and nutritional guidance on body composition of obese adolescents assessed by bone densithometer (dexa)

Este estudo foi desenvolvido com a finalidade de avaliar o efeito da atividade física moderada, associada à orientação nutricional, sobre a composição corporal de adolescentes obesos, para esse propósito, 11 adolescentes (7 = 12,8 anos) foram submetidos a exercício aeróbio (cicloergômetro - 60% FC máx), em duas sessões semanais, durante nove meses, sendo avaliada a composição corporal por Densitometria Óssea antes e após o período de treinamento. Os valores iniciais (I) e finais (F) para as variáveis antropométricas e da composição corporal foram: IMC (I: 33,3 ± 5,2; F: 31,8 ± 6,9* kg/m2); percentual de gordura corporal (I: 48,5 ± 6,7; F: 47,2 ±5,1* %); peso de massa magra (I: 40,6 ± 4,9; F- 42,5 ± 5,4* kg). Tais resultados indicam que, houve um aumento significativo no peso da massa magra e reduções na porcentagem de gordura corporal e no índice de Massa Corpórea (IMC). Isto sugere um provável efeito do programa de treinamento e da orientação nutricional. As adaptações observadas no presente estudo nos permitem sugerir que o exercício aeróbio e a orientação nutricional podem promover importantes adaptações sobre a composição corporal de adolescentes obesos, atenuando os efeitos adversos decorrentes da obesidade

Effect of moderate exercise on the severity of clinical signs associated with influenza virus infection in horses.

The purpose of this experiment was to determine if exercising horses, infected with influenza virus, exacerbates the severity of clinical disease. Eight horses were trained on a treadmill for 42 days and then challenged with aerosolised influenza A/equine/Kentucky/91 (H3N8). Following challenge, 4 horses (exercise group) continued training for 28 days, while the other 4 horses (nonexercise group) were confined to their stalls. All horses developed clinical signs within 36 h of challenge (fever, coughing, and mucopurulent nasal discharge) and clinical scores were greater in the exercise group. Horses developed fever from Days 1-11 post challenge (PC) and were tachypnoeic and tachycardic from Days 1-14 PC. All horses lost weight within 4 days PC, but the exercise group lost an average of 20 kg more than the nonexercise group. All horses developed pneumonia, and ultrasonography revealed pulmonary consolidation and oedema by Day 7 PC that was resolving by Day 14 PC. Endoscopy and transtracheal aspirates showed airway inflammation for up to 21 days PC. While the exercise group exhibited more severe signs of clinical disease, resolution occurred for both groups on approximately Day 14 PC, and no adverse effects were noted at the end of the study. However, the potential long term effects of exercising horses acutely infected with influenza virus are unknown. Until further research is conducted in this area, it appears prudent not to exercise affected horses.

Effect of Moderate Exercise on Blood Flow in the Gastrointestinal Tract in Trained Conscious Miniature Swine

Aim: To examine how moderate exercise affects the blood flow in the gastrointestinal tract. Materials and Methods: Twelve miniature swine weighing 38–43 kg were used. All animals were trained on a cardiac exercise treadmill. Blood flow measurements were done on conscious animals using labeled microspheres with a diameter of 16.5 ± 0.1 (SD) µm. The first flow was measured while the animal was awake and resting, the second flow after 15 min of exercise, the third flow after 30 min of rest. Results: Flow in the oesophagus at rest was 19.5 ± 1.3 (SEM) ml/min/100 g. During exercise the flow decreased to 13.3 ± 1.2 (SEM) ml/min/100 g (ns). After 30 min of rest the flow was 9.9 ± 1.2 (SEM) ml/min/100 g (p < 0.05 when comparing the flow before and after exercise). Flow in the cardia at rest was 23.1 ± 1.3 (SEM) ml/min/100 g. During exercise the flow decreased to 14.0 ± 1.2 (SEM) ml/min/100 g (p < 0.05). After 30 min of rest the flow was 15.0 ± 1.2 (SEM) ml/min/100 g. Flow in the pylorus at rest was 38.9 ± 1.1 (SEM) ml/min/100 g. During exercise the flow decreased to 24.6 ± 1.1 (SEM) ml/min/100 g (p < 0.01). After 30 min of rest the flow was 26.9 ± 1.2 (SEM) ml/min/100 g. Blood flow in the small and large intestine was mainly unaffected by moderate exercise. Conclusion: Under moderate exercise, blood flow in the upper part of the gastrointestinal tract declines while it is mainly unaffected in the duodenum, small and large intestine.