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Susan Shore and Roy J. Shephard

Immune responses have been examined in 11 children aged 10.3 ± 0.6 years before and after 12 weeks of aerobic training. Initial resting data showed high total lymphocyte, CD3+ and CD8+ counts, a low CD4+/CD8+ ratio and a low CD25+ count relative to young adults. Acute exercise (30 min at ventilatory threshold) initially increased CD4+, CD8+, and CD56+ counts, and decreased CD4+/CD8+ ratio, but CD56+ count did not decrease during recovery. After training, relative aerobic power remained unchanged at 50 ±3 ml · kg−1 · min−1. However, resting leukocyte, CD3’ and CD25’ counts were decreased, and acute exercise induced smaller changes in leukocyte and subset counts. We conclude that immune responses to exercise are generally similar in children and young adults.

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Jeffrey A. Woods and Brandt D. Pence

Exercise immunology is a relatively new discipline in the exercise sciences that seeks to understand how exercise affects the immune system and susceptibility to infectious and chronic diseases. This brief review will focus on three major observations that have driven the field to date including: (1) acute exercise-induced leukocytosis, (2) the observation that intense, prolonged exercise results in upper respiratory tract symptoms, and (3) the paradoxical effect of acute and chronic exercise on inflammation. This framework will be used to examine the mechanisms and implications behind these seminal observations. Data generally support the conclusion that moderate intensity exercise enhances immune function, whereas prolonged, intense exercise diminishes immune function.

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Fiona Barnett

Background:

This study examined the self-efficacy and affective responses to an acute exercise bout in sedentary older and younger women to determine whether aging has an effect on affective states.

Methods:

Twenty-five sedentary younger (mean age = 19.9 yrs) and 25 older (mean age = 55.7 yrs) women completed an acute bout of exercise. Affective responses were measured before, during, and immediately following exercise. Self-efficacy responses were measured before and immediately following exercise.

Results:

Positive engagement, revitalization, tranquility, Felt Arousal and Feeling Scale responses, and self-efficacy were all higher immediately following compared with before or during exercise for both groups of women. In addition, older women experienced higher overall positive engagement and lower physical exhaustion compared with younger women as well as higher tranquility and Feeling Scale responses immediately following exercise.

Conclusions:

This investigation found that an acute bout of moderate-intensity exercise produced more positive and fewer negative affective states in both younger and older women.

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Caterina Pesce, Lucio Cereatti, Rita Casella, Carlo Baldari and Laura Capranica

This study investigated the visual attention of older expert orienteers and older adults not practicing activities with high attentional and psychomotor demands, and considered whether prolonged practice of orienteering may counteract the age-related deterioration of visual attentional performance both at rest and under acute exercise. In two discriminative reaction time experiments, performed both at rest and under submaximal physical workload, visual attention was cued by means of spatial cues of different sizes followed, at different stimulus-onset asynchronies, by compound stimuli with local and global target features. Orienteers, as compared to nonathletes, showed a faster reaction speed and a complex pattern of attentional differences depending on the time constraints of the attentional task, the demands on endogenous attentional control, and the presence or absence of a concomitant effortful motor task. Results suggest that older expert orienteers have developed attentional skills that outweigh, at least at rest, the age-related deficits of visual attentional focusing.

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Brian C. Focht and Heather A. Hausenblas

The primary purpose of the present study was to examine psychological responses of 50 young women following single episodes of aerobic exercise (AE) performed in a naturalistic exercise setting and quiet rest (QR). Given the salience of self-presentational qualities in a naturalistic exercise setting, a secondary purpose was to examine whether psychological responses to acute exercise varied as a function of social physique anxiety (SPA). The dependent measures of state anxiety, positive engagement, revitalization, tranquility, and physical exhaustion were assessed immediately prior to and then at 5 and 30 minutes following each condition. It was found that (a) AE and QR were associated with decreases in state anxiety and increases in tranquility; (b) AE was associated with increases in positive engagement and revitalization; and (c) these changes did not vary as a function of SPA level.

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Margaret Schneider, Andrea Dunn and Daniel Cooper

Many adolescents do not meet public health recommendations for moderate-to-vigorous physical activity (MVPA). In studies of variables influencing adolescent MVPA, one that has been understudied is the affective response to exercise. We hypothesized that adolescents with a more positive affective response to acute exercise would be more active. Adolescents (N = 124; 46% male) completed two 30-min exercise tasks (above and below the ventilatory threshold [VT]), and wore ActiGraph accelerometers for 6.5 ± 0.7 days. Affective valence was assessed before, during, and after each task. A more positive affective response during exercise below the VT was associated with greater participation in MVPA (p < .05). The results are consistent with the hypothesis that individuals who have a more positive affective response to exercise will engage in more MVPA. To promote greater participation in MVPA among adolescents, programs should be designed to facilitate a positive affective experience during exercise.

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Marcin Baranowski, Jan Górski, Barbara Klapcinska, Zbigniew Waskiewicz and Ewa Sadowska-Krepa

We have previously shown that acute exercise increases the level of sphingosine-1-phosphate (S1P) in plasma and ceramide in erythrocytes of untrained subjects. The aim of the current study was to examine the effect of ultramarathon run on the plasma and erythrocyte levels of the following bioactive sphingolipids: S1P, sphinganine-1-phosphate (SA1P), sphingosine, sphinganine, and ceramide. Blood samples were collected from seven male amateur runners participating in a 48-hr ultramarathon race before the run, after 24 and 48 hr of running, and following 24 and 48 hr of recovery. The sphingolipids were quantified by means of HPLC. Sustained running for 48 hr resulted in a progressive decline in plasma S1P to a level significantly lower than at prerace, and then remained stable over the next 48 hr of recovery. In erythrocytes, S1P content was stable until 24 hr of recovery, then rose abruptly to reach peak values after 48 hr of recovery. The plasma level of SA1P decreased progressively during the competition and remained unchanged over the recovery. In erythrocytes, the level of SA1P increased after 24 hr running and normalized thereafter. The level of ceramide, both in plasma and erythrocytes, was not significantly affected by the ultraendurance run. We speculate that reduction in plasma level of S1P during and after the run reduces its biological actions and might be responsible for some negative side-effects of the ultraendurance effort.

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Keith Tolfrey, Julia K. Zakrzewski-Fruer and James Smallcombe

Three publications were selected based on the strength of the research questions, but also because they represent different research designs that are used with varying degrees of frequency in the pediatric literature. The first, a prospective, longitudinal cohort observation study from 7 to 16 years with girls and boys reports an intrinsic reduction in absolute resting energy expenditure after adjustment for lean mass, fat mass, and biological maturity. The authors suggest this could be related to evolutionary energy conservation, but may be problematic now that food energy availability is so abundant. The second focuses on the effect of acute exercise on neutrophil reactive oxygen species production and inflammatory markers in independent groups of healthy boys and men. The authors suggested the boys experienced a “sensitized” neutrophil response stimulated by the exercise bout compared with the men; moreover, the findings provided information necessary to design future trials in this important field. In the final study, a dose-response design was used to examine titrated doses of high intensity interval training on cardiometabolic outcomes in adolescent boys. While the authors were unable to identify a recognizable dose-response relationship, there are several design strengths in this study, which was probably underpowered.

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Alfredo Córdova, Antoni Sureda, María L. Albina, Victoria Linares, Montse Bellés and Domènec J. Sánchez

The aim was to determine the levels and activities of the oxidative stress markers in erythrocytes, plasma, and urine after a flat cyclist stage. Eight voluntary male professional trained-cyclists participated in the study. Exercise significantly increased erythrocyte, leukocyte, platelet, and reticulocyte counts. The exercise induced significant increases in the erythrocyte activities of catalase (19.8%) and glutathione reductase (19.2%), while glutathione peroxidase activity decreased significantly (29.3%). Erythrocyte GSSG concentration was significantly increased after exercise (21.4%), whereas GSH was significantly diminished (20.4%). Erythrocyte malondialdehyde levels evidenced a significant decrease 3 h after finishing the stage (44.3%). Plasma malondialdehyde, GSH and GSSG levels significantly decreased after 3 hr recovery (26.8%, 48.6%, and 31.1%, respectively). The exercise significantly increased the F2-isoprostane concentration in urine from 359 ± 71 pg/mg creatinine to 686 ± 139 pg/mg creatinine. In conclusion, a flat cycling stage induced changes in oxidative stress markers in erythrocytes, plasma, and urine of professional cyclists. Urine F2-isoprostane is a more useful biomarker for assessing the effects of acute exercise than the traditional malondialdehyde measurement.

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Désirée B. Maltais, Claire Gane, Sophie-Krystale Dufour, Dominik Wyss, Laurent J. Bouyer, Bradford J. McFadyen, Karl Zabjek, Jan Andrysek and Julien I.A. Voisin

Little is known about the effects of acute exercise on the cognitive functioning of children with cerebral palsy (CP). Selected cognitive functions were thus measured using a pediatric version of the Stroop test before and after maximal, locomotor based aerobic exercise in 16 independently ambulatory children (8 children with CP), 6–15 years old. Intense exercise had: 1) a significant, large, positive effect on reaction time (RT) for the CP group (preexercise: 892 ± 56.5 ms vs. postexercise: 798 ± 45.6 ms, p < .002, d = 1.87) with a trend for a similar but smaller response for the typically developing (TD) group (preexercise: 855 ± 56.5 ms vs. postexercise: 822 ± 45.6 ms, p < .08, d = 0.59), and 2) a significant, medium, negative effect on the interference effect for the CP group (preexercise: 4.5 ± 2.5%RT vs. postexercise: 13 ± 2.9%RT, p < .04, d = 0.77) with no significant effect for the TD group (preexercise: 7.2 ± 2.5%RT vs. postexercise: 6.9 ± 2.9%RT, p > .4, d = 0.03). Response accuracy was high in both groups pre- and postexercise (>96%). In conclusion, intense exercise impacts cognitive functioning in children with CP, both by increasing processing speed and decreasing executive function.