Although many cytokines recruiting and priming neutrophils and monocytes were secreted and functional after exhaustive exercise, overwhelming antioxidant and antiinflammatory defenses were induced, preventing exercise-induced oxidative stress.

To investigate the mechanisms of exercise-induced immune perturbations, we measured promising immunomodulatory hormones and cytokines in plasma of 16 male marathon runners before and after a competitive 42.195-km race. Interleukin 1-beta (IL-1beta) and interferon gamma (IFN-gamma) concentrations remained unchanged after the marathon. The cytokines IL-12, IFN-alpha and tumour necrosis factor alpha (TNF-alpha) could not be detected even using highly sensitive specific immunoassays, indicating at least that overshooting responses of these cytokines had not occurred after exercise. As mechanisms for the small changes in these cytokines, we demonstrated for the first time a significant rise in concentrations of inhibitory cytokine IL-10 in addition to the immunosuppressive hormone cortisol, although concentrations of IL-4 and transforming growth factor-beta (TGF-beta) were unaffected by the race. Furthermore, concentrations of IL-1 receptor antagonist (IL-1ra) and IL-6, which are negative-feedback inhibitors of cytokine production, increased by more than 100 times. As for humoral mediators of neutrophil mobilization, concentrations of growth hormone (GH), cortisol and granulocyte colony-stimulating factor (G-CSF) increased significantly. In addition, concentrations of neutrophil-priming substances (IL-6, IL-8, G-CSF, GH and prolactin) also increased significantly and the induction of IL-8 and G-CSF with exercise was demonstrated for the first time in the present study. In contrast, IL-2 concentration decreased, by 32%, and this was correlated with the induction of nitric oxide (NO) production. Muscle damage, monitored using changes in concentrations of creatine kinase and myoglobin, was also observed. These results suggested that exercise-induced pathogenesis including previously reported immunosuppression and neutrophil hyper-reactivity might be attributed, at least partly, to the systemic dynamics of the above bioactive substances.

A full marathon is the longest running race in official track events and is a form of acute exercise. However, no studies have examined the acute neutrophil function response to a competitive marathon race. Thirty-six male athletes who had just completed the 42.195 km course of the 50th Beppu-Oita Mainichi Marathon were enrolled in this study. Neutrophil oxidative burst activity, phagocytic activity and expression of CD11b and CD16 per cell were measured by flow cytometry immediately before and after the marathon. Total leukocyte/neutrophil counts increased significantly (p < 0.001), whereas total oxidative burst activity per neutrophil cell decreased significantly after the race (p < 0.001). Furthermore, total phagocytic activity per neutrophil cell also decreased after the race, although it was not significant (p = 0.08). Although CD11b expression per cell did not change, the expression of CD16 per cell significantly decreased (p < 0.001) after the race. In conclusion, a competitive marathon race decreased neutrophil functions (oxidative burst activity and phagocytic activity), which may be partly due to a decrease in CD16 expression. The increase in total neutrophil counts might reflect a compensatory response to counteract the decrease in neutrophil functions.

Exhaustive exercise such as long-distance running has been shown to increase susceptibility to infection. In order to investigate whether serum opsonic activity plays a role in such conditions, we utilized luminol-dependent and lucigenin-dependent chemiluminescence (LmCL and LgCL). We took serum samples from 24 male marathon runners before and after running 30 km. Neutrophils were isolated from the peripheral blood of healthy volunteers. Serum opsonic activity was examined by measuring neutrophil ROS stimulated with zymosan particles opsonized by the serum samples. Immunoglobulin and complement levels in the serum were also measured. After a 30 km run, the maximum light emission was increased and the time to reach the maximum light emission was shortened significantly (p < 0.05) in LmCL. However, there were no significant changes in the immunoglobulin and complement levels. The increase of ROS production may suggest that serum opsonic activity is accelerated after running 30 km. Thus, serum opsonic activity might not play a significant role in the susceptibility to infection after long-distance running.

We studied changes in physical characteristics: body composition; muscle and physical strength; hematological parameters; and nutrients and food intake in 22 male college judoists who were losing weight purposefully. Nutritional parameters in blood, such as triglyc.erides, decreased immediately before matches and rebounded after matches. Free fatty add increased before matches and returned to previous levels 10 days after matches. IgM and complements decreased before matches and did not return to previous levels even 10 days after matches. These changes were noted in the marked weight reduction group (weight lost / body weight before weight reduction, weight reduction rate>6%). In contrast, creatine kinase increased before matches in the slight and moderate weight reduction groups (weight reduction rate< 3%, 3~-and<6%, respectively). The marked weight reduction group showed no changes in creatine kinase, however, indicating inadequate exercise due to excessive weight reduction. Muscle strength (grip) and nutrients and food intake decreased significantly before matches. These changes were noted in the marked weight reduction group. These findings suggested that a weight reduction rate of 6% or more adversely affected the performance and health of the judoist.

Although it is generally thought that habitual exercise protects an individual from infections, few careful scientific studies have been conducted. To clarify the influences of physical training on non-specific humoral immunity, both serum opsonic activity, which is a more direct indicator for the strength of non-specific humoral immunity to infections, and serum immunoglobulin and complement levels of 18 healthy male volunteers were assayed before and after a 10-week of training as indices of immuno defense.The serum levels of three immunoglobulins (IgG, IgA and 1gM) and one complement(C3) were compared prior to and immediately after exercise both before and after training. Paired t-test revealed that before training exercise-induced increases in IgG and C 3 were significant and after training increases in IgG, IgA, IgM and C 3 were significant. But baseline (prior to exercise) levels of these immunoglobulins and complement were significantly suppressed during the training period.Serum opsonic activity was compared with each other in the same way as serum protein levels. The noutrophilic chemiluminescence Peak Height (PH), which is one of the indicators of serum opsonic activity, was significantly decreased immediately after exercise at the beginning stage of the training. After the training period, serum opsonic activity showed no noteworthy exercise-induced variations and baseline levels were slightly increased during the training period.These findings suggest that resistance and reactivity to the physical stress are improved and the non-specific humoral immunity, self-defense ability against infections, is considered to be improved by the training.(Jpn. J. Phys. Fitness Sports Med. 1994, 43 : 7583)

No abstract

The principal objective of this paper is to develop a simple and rapid method of estimating levels of fatigue so that chronic fatigue can be prevented. Long-distance runners belonging to a successful corporate team (Group A; 25 males) and representative runners at the prefectural level (Group B; 14 males) participated in this study. We examined the effects of strenuous physical exercise on serum enzyme activity and the fatigue level felt by the runners (subjective fatigue).The following parameters were measured on two consecutive mornings during a training period: physical characteristics, serum-biochemistry using the dry-chemistry method, and subjective fatigue determined using the questionnaire regarding subjective symptoms authorized by the Japan Association of Industrial Health and the Profile of Mood State (POMS). Group A was divided into A-Senior (17 males; highest performance level) and AFreshman (8 males) subgroups according to the length of employment within the corporation (one year or more and less than one year, respectively).The levels of serum aspartate aminotransferase (AST) and creatine kinase (CK) were significantly lower in the A-Senior group than the other groups and this group displayed the "iceberg" POMS profile at both examinations. Some significant correlations between the elements of POMS and serum enzyme activity levels were observed among all three groups during both examinations. The decline of serum CK levels tended to accompany a decrease in "Fatigue" according to POMS among 9 of 17 members of the A-Senior group. This tendency between the A-Senior and the A-Freshman groups statistically differed according to the Xsquare analysis.Our results suggest that the effects of physical stress on serum enzyme activity levels and subjective fatigue are affected by performance levels. Physical fatigue seemed to be reflected by serum CK levels. Monitoring subjective fatigue while measuring serum enzyme activity levels using the dry-chemistry method immediately provides dinical value to players and coaches on site, and should therefore help to prevent a shift from "overreaching" to "overtraining".