Effect of water polo practice on cytokines,growth mediators,and leukocytes in girls

PURPOSE: The effects of exercise on growth and development are mediated through a complex interaction between the endocrine, immune, and nervous systems. Very little is known about how these systems respond to exercise in children or adolescents. Moreover, there are few studies that have examined growth factors, inflammatory cytokines, and leukocyte responses to "real-life" or field exercise solely in girls. Thus, the goal of the present study was to determine the acute exercise-induced alterations in the growth hormone --> insulin-like growth factor-I axis, inflammatory cytokines, and certain aspects of immune function in a group of adolescent girls after a typical water polo practice. METHODS: Ten, healthy, high-school female subjects, 14-16 yr old, performed a single, typical, 1.5-h water polo practice session. Blood was sampled before and after the session. RESULTS: The exercise resulted in an increase in HR (from 82 +/- 2 to 161 +/- 5 beats.min(-1) at 30 min, P < 1.4.10(-6) ), as well as in circulating lactate levels (375 +/- 66%, P < 0.0005). Significant increases where noted in circulating IL-6 (396 +/- 162%, P < 0.005) and IL-1ra (71 +/- 20%, P < 0.015). A substantial increase in the level of IGFBP-1 (1344 +/- 344%, P < 0.001) was also observed. Interestingly, TNF-alpha levels decreased after the exercise (-10.4 +/- 3.8%, P < 0.04) as did insulin (55 +/- 12%, P < 0.005). The exercise led to significant increases in granulocytes, monocytes, and lymphocytes. The exercise significantly influenced adhesion molecules (such as CD62L and CD54), which has not been previously studied in adolescent girls. CONCLUSIONS: These data demonstrate that an intense "real-life" exercise bout in adolescent females leads to profound increases in inflammatory cytokines and reductions in anabolic mediators with substantial alterations in white blood cell subpopulations and adhesion molecules. The role of these frequent, almost daily immune and cytokine changes on growth and development have yet to be determined.     

Differences in the cellular and humoral immune system between middle-aged men with different intensity and duration of physically training

AIM: The effects of acute exercise on immune system and serum magnesium and iron have been investigated in recent years. However, data related to the comparisons of long-term physical training with different intensity and duration are limited. METHODS: The association between long-term physical training and cellular (lymphocyte phenotyping) and humoral immune parameters (serum immunoglobulins) and serum magnesium and iron values in the middle-aged men was investigated. Eleven male master athletes (MA) performing high intensity and long duration training, 11 male recreational athletes (RA) performing moderate intensity and duration training (>10 years) participated. Eleven male sedentary individuals were enrolled as control group (CG). RESULTS: The percentages of total CD3+ T cells, CD4+ T helper, CD8+ T suppressor/cytotoxic, CD19+ B cells, natural killer cells, HLA-DR+ active T cells and CD4/CD8 ratios did not show any significant difference among 3 groups. In MA, VO2max values showed a significant negative correlation with CD4+ T helper cells. There were no significant differences among MA, RA and CG in terms of IgG, IgA, and IgM concentrations. There was a significant correlation between VO2max and IgG in RA. Iron, iron binding capacity and ferritin were found similar in all groups, but serum magnesium level in MA was significantly lower than RA and CG. CONCLUSION: No exact data to support immunosuppression or immunostimulation could be obtained except a significant negative correlation between CD4+ T helper cells and VO2max values in MA and a positive correlation between serum IgG and VO2max ivalues in RA. These findings may be the indirect markers of cellular immune system suppression by intensive exercises and stimulation of IgG production by moderate exercises.     

Immune status of physically active women during lactation

PURPOSE: The purpose of this study was to provide baseline data on immune status of exercising and sedentary exclusively lactating women. Dietary intake and body composition were also investigated to determine whether they related to immune function. METHODS: Healthy, exclusively breastfeeding women with a body mass index between 20 and 30 kg x m were studied at 3 months postpartum. Participants in the exercise group (EG; N = 27) exercised aerobically at least 30 min x d, 3x wk, and women in the sedentary group (SG; N = 23) exercised once a week or less during the previous 6 wk. Immune status while at rest was determined by measuring: 1) a complete blood cell count and differential leukocyte count; 2) percentages and absolute counts of peripheral blood T cells (CD3+), cytotoxic T cells (CD3+CD8+), helper T cells (CD3+CD4+), B cells (CD19+), and natural killer cells (CD56+); 3) neutrophil bacterial killing and oxidative burst activity; and 4) in vitro mitogenic responsiveness of lymphocytes. Cardiorespiratory fitness, body composition, and dietary intake were also measured. RESULTS: Participants in the EG had a significantly higher level of mean predicted cardiorespiratory fitness than women in the SG (39.5 +/- 1.1 vs 32.5 +/- 1.0 mL O2 x min x kg; P < 0.05); however, there were no significant differences in body composition or dietary intake. There were no significant differences in any of the indicators of immune status between groups. In addition, there were no significant relationships between body composition or dietary intake and immune status. CONCLUSIONS: The results of this study suggest that women may exercise moderately during lactation and increase their fitness level without impairing their immune function.     

Changes in lymphocyte subpopulations after prolonged exercise

In order to assess the changes in the cellular immune system, 27 healthy male subjects were selected who participate in leisure-time sports and in whom measurements of the lymphocyte subsets in venous blood were carried out before and after a standardized endurance exercise test (EI, 60 minutes in length, intensity: 63% of maximum performance). The percentages of the following parameters were measured: total T-lymphocytes, B-lymphocytes and O-lymphocytes as well as T4-lymphocytes (helper T-lymphocytes, CD4+) and T8-lymphocytes (cytotoxic/suppressor T-lymphocytes, CD8+). In a subgroup consisting of 8 subjects, the parameters indicated above were measured again 24 hours following E. In order to check the reproducibility of the findings, the endurance exercise test was repeated 21/2 weeks later (EII).     

Immune function during and after 60 min of moderate exercise wearing protective clothing

INTRODUCTION: As exercise while wearing protective clothing exacerbates body heat storage compared to exercise in the heat, and as exercise alters immune responses, it appeared worthwhile to examine immune and stress responses while wearing protective clothing during moderate exercise. METHODS: Eight subjects completed two bouts of exercise at 45% Vo2(max) in a thermoneutral environment: once while wearing shorts only (Control trial, CON) and again while wearing protective clothing (PRO). Venous blood samples were taken to analyze TNF-alpha mRNA by RT-PCR in LPS stimulated blood, plasma catecholamines, and cortisol. Blood cell count was analyzed by flow cytometry. Rectal temperature (T(re)) was monitored continuously. RESULTS: Exercise with PRO resulted in significantly greater increases in T(re) (39.2 +/- 0.2 degrees C in PRO vs. 38.0 +/- 0.1 degrees C in CON) and plasma epinephrine and norepinephrine (+70% and 150%, respectively). Plasma cortisol increased only at the end of PRO exercise (+33%). Leukocyte and lymphocyte cell count was 14% and 18% higher, respectively, but there were no significant changes in T cytotoxic and NK cell counts compared to the CON trial. Only T helper lymphocyte count was lower (-29%). During both exercise trials, T helper lymphocytes were significantly decreased at the end of exercise and recovery. With or without protective clothing, exercise was associated with an inhibition of TNF- alpha expression in stimulated monocytes (approximately -50% at min 20 and 40, and approximately -30% at min 60). DISCUSSION: Protective clothing wearing induces significant thermal challenge during exercise. The inhibition of TNF-alpha appears to be mediated primarily by exercise and not the added thermal load associated with protective clothing.     

The effects of moderate exercise training on immune response

The relationship between moderate exercise training (ET) (five 45-min sessions per week, brisk walking at 60 heart rate reserve for 15 wk) and changes in immune system variables and function was investigated in a group of 36 sedentary, mildly obese women. The study was conducted using a two (exercise (EX) and nonexercise (NEX) groups) by three (baseline, 6 wk, and 15 wk testing sessions) factorial design, with data analyzed using repeated measures ANOVA. The pattern of change over time between groups for number of peripheral blood lymphocytes (total), T cells (CD5), B cells (CD20), and serum IgG, IgA, and IgM levels was significantly different. This was not the case for spontaneous blastogenesis or number of T helper/inducer cells (CD4) or T cytotoxic/suppressor cells (CD8). Within-EX-group changes were characterized by significant decreases in percentage and number of total lymphocytes, and in T cell number after 6 wk, and significant increases in each of the serum immunoglobulins after both 6 and 15 wk of training. B cell number increased significantly in NEX subjects relative to baseline values at both 6 and 15 wk, with no significant changes experienced in EX subjects. In summary, these data suggest that moderate ET is not associated with an improvement in lymphocyte function but is associated with a 20% increase in serum immunoglobulins and several small changes in circulating numbers of immune system variables, highlighted by significant decreases in circulating numbers of lymphocytes, particularly the T cell subpopulation. These changes were especially apparent after 6 wk of training, with some attenuation by 15 wk.     

High-Intensity Training Reduces CD8+ T-cell Redistribution in Response to Exercise

PURPOSE: We examined whether exercise-induced lymphocytosis and lymphocytopenia are impaired with high-intensity training. METHODS: Eight trained cyclists (V˙O2max = 64.2 ± 6.5 mL·kg·min) undertook 1 wk of normal-intensity training and a second week of high-intensity training. On day 7 of each week, participants performed a cycling task, consisting of 120 min of submaximal exercise followed by a 45-min time trial. Blood was collected before, during, and after exercise. CD8 T lymphocytes (CD8TLs) were identified, as well as CD8TL subpopulations on the basis of CD45RA and CD27 expression. RESULTS: High-intensity training (18,577 ± 10,984 cells per microliter × ～165 min) was associated with a smaller exercise-induced mobilization of CD8TLs compared with normal-intensity training (28,473 ± 16,163 cells per microliter × ～165 min, P = 0.09). The response of highly cytotoxic CD8TLs (CD45RACD27) to exercise was smaller after 1 wk of high-intensity training (3144 ± 924 cells per microliter × ～165 min) compared with normal-intensity training (6417 ± 2143 cells per microliter × ～165 min, P < 0.05). High-intensity training reduced postexercise CD8TL lymphocytopenia (-436 ± 234 cells per microliter) compared with normal-intensity training (-630 ± 320 cells per microliter, P < 0.05). This was driven by a reduced egress of naive CD8TLs (CD27CD45RA). High-intensity training was associated with reduced plasma epinephrine (-37%) and cortisol (-15%) responses (P < 0.05). CONCLUSIONS: High-intensity training impaired CD8TL mobilization and egress in response to exercise. Highly cytotoxic CD8TLs were primarily responsible for the reduced mobilization of CD8TLs, which occurred in parallel with smaller neuroendocrine responses. The reduced capacity for CD8TLs to leave blood after exercise with high-intensity training was accounted for primarily by naive, and also, highly cytotoxic CD8TLs. This impaired CD8TL redistribution in athletes undertaking intensified training may imply reduced immune surveillance.     

Expression of lymphocyte subsets after exercise and dexamethasone in high and low stress responders

PURPOSE: Recent work indicates that among the normal population, persons can be classified as low (LR) or high (HR) stress responders based on hypothalamic-pituitary-adrenal (HPA) axis responses to high-intensity exercise. We studied whether differential activation of the HPA axis affected cytokine production and expression of selected lymphocyte subsets in HR and LR in response to high-intensity exercise after placebo and dexamethasone (DEX; 4 mg). METHODS: Healthy HR (N = 12) and LR (N = 10) underwent two exercise tests at 90% of VO2max, 8 h after placebo or DEX. Expression of lymphocyte surface markers (CD3+, CD4+, CD8+, CD56+), adhesion molecule markers (intercellular adhesion molecule-1/ICAM-1: CD54+ and L-selectin: CD62L+), and concentrations of plasma interleukin 6 (IL-6) were examined before and after exercise. RESULTS: Baseline percentages of CD8+ and CD56+ cells were significantly higher, and concentrations of IL-6 and percentages of CD4+ cells were significantly lower in HR as compared with LR. The percentage of CD54+ and CD62L+ cells was not significantly different in HR and LR. DEX significantly reduced the percentage of CD3+ and CD4+ and increased the percentage of CD8+ and CD56+ subsets; the percent of cells expressing CD54+ increased, whereas CD62L+ decreased. Exercise-induced changes in the percentage of lymphocyte subsets were similar to those induced by DEX. CONCLUSION: In summary, HR and LR have different baseline patterns of IL-6 and lymphocyte subsets, which may reflect differential sensitivity to endogenous glucocorticoids. However, exogenous glucocorticoids induced similar patterns of lymphocyte expression in HR and LR.     

Naive and memory T cell subsets are differentially mobilized during physical stress

This study examined the naive and memory phenotypic profiles of CD4+ and CD8hi T cells that were mobilized to the peripheral circulation during a combination of aerobic exercise and heat stress, determining expression of the adhesion molecules CD62L and CD11a on the recruited cells. Twelve recreationally active males (age 27.1 +/- 5.3 yr, height 1.77 +/- 0.08 m, mass 76.9 +/- 12.0 kg, VO2peak 43.9 +/- 6.7 mL x kg(-1) x min(-1)) completed a 40 min bout of cycle ergometry at 65 % of VO2peak while immersed to mid-chest in a water bath at 39 degrees C. Venous blood samples were collected before (T0), during (T40) and 30 min after (T70) exposure to combined exercise and heat stress. Specimens were analyzed by three-colour flow cytometry for CD4+ and CD8hi T cell expression of CD45RO, CD11a and CD62L. Some 80 % of the CD4+ T cells that were mobilized were of the CD45RO memory phenotype, with the numbers of CD11alo and CD62L+ cells increasing more than those of CD11ahi and CD62L- cells. For the CD8hi cells, there was a more equal recruitment of CD45RO- naive (43 %) and CD45RO+ memory (57 %) cells. The majority (84 %) of recruited CD8+ cells were CD11ahi; there was a trend to predominance of CD62L- cells (57 %) for the memory subset, but with almost equal recruitment of CD62L+/- for the naive subset. We conclude that the exercise + heat stress induced trend to an increase in CD4+ T cells is linked in some way to memory phenotype; it cannot be explained simply by a high density expression of CD11a and lack of the lymph node homing receptor (CD62L). Furthermore, although mobilization of CD8hi T cells is not linked to memory phenotype, a high density expression of CD11a and a lack of the lymph node homing receptor are important determinants of CD8hi T cell mobilization.     

Immune system alteration in response to increased physical training during a five day soccer training camp

Leukocyte and monocyte subpopulations were investigated in ten elite male soccer players before and after a 5-day training camp. It was hypothesized that with increased training intensity and duration, the immune system would show signs of depression. Blood samples were taken at rest before and after the training camp and cell surface antigens were investigated by four-colour flow cytometry. After five days of intensified training, there was a significant decrease in the number of T helper, T cytotoxic and B cells, the expression of CD11 b on leukocytes increased and the NK cell population did not change significantly. It is concluded that after a period of intensified training, soccer players may experience decreased T and B cell numbers in circulation, possibly affecting their capability to activate the immune system and resist infections. However, in contrast to the acute decrease in the number of circulating NK cells commonly observed after physical exercise, no change in this cell population was observed at rest after a period of intensified physical training. Exercise-induced immunological changes were highly differentiated between different leukocyte subpopulations.     

Novel nutritional immune formula maintains host defense mechanisms

Military combat and training stress induce immune changes that increase the risk of infection and ultimately influence soldiers' performance and readiness. Strenuous military training/assessment provides a uniform stress and the opportunity to evaluate nutritional strategies to minimize stress-induced immune changes that predispose soldiers to infection. Immunological changes and effects of a novel nutritional immune formula (NNIF) were examined prospectively in a double-blind, controlled study of 200 soldiers attending Special Forces Assessment and Selection School. Immune function was measured by skin delayed-type hypersensitivity, lymphocyte phenotyping, mitogenic proliferative responses, and granulocyte function. Approximately 50% of soldiers completed the study (control, n = 57; NNIF, n = 50). Several stress-induced lymphocyte changes were observed (decreased mitogen-induced proliferation, T and total lymphocytes, and interferon-gamma-producing lymphocytes and increased percentage of neutrophils). NNIF modified several changes, including delayed-type hypersensitivity responses (NNIF, 78%; control, 59%; p < 0.05), increased proportions of helper T cells, activation of B cells, enhanced neutrophil phagocytosis, and attenuation of declines in certain functional subpopulations (i.e., cytotoxic/ suppressor lymphocytes). Soldiers who consumed NNIF experienced less stress-induced immune impairment, thereby lowering the risk of infection.     

Serum amino acid responses to three different exercise sessions in male power athletes

BACKGROUND: The purpose of this study was to investigate serum amino acid responses to 3 different exercise sessions in male power athletes (sprinters and jumpers; n=11). METHODS: All subjects performed 2 running exercise sessions: a short run session (SRS) of 3 x 4 x 60 m with recoveries of 120 and 360 sec, and a long run session (LRS) of 20 sec runs with recoveries of 100 sec until exhaustion. Ten subjects performed a strength exercise session (SES) of 90 min. Serum amino acids (n=21) were assayed 10 min before and 10 min after the sessions. Peak blood lactate was analyzed from fingertip blood samples taken 1 and 5 min after the sessions. RESULTS: The before-after comparisons showed that the essential amino acids (EAAs) decreased by 8.7% (p<0.01) and alanine increased by 26.7% (p<0.001) after SRS. Following LRS the EAAs decreased also by 8.7% (p<0.01) and alanine increased by 25.3% (p<0.001). In the sum of all amino acids there were no changes after SRS and LRS but a significant decrease (14.8%; p<0.01) was observed after SES. Also the EAAs decreased (20.6%; p<0.001) but alanine, taurine and citrulline were the only single amino acids with no changes after SES. The peak blood lactate concentrations after SRS, LRS and SES were 13.8+/-1.9, 16.4+/-1.3 and 2.5+/-0.4 mmol/L, respectively. The lactate value after SES differed (p<0.001) from the values observed after SRS and LRS. The comparison of the changes in the serum amino acid concentrations following the 3 exercise sessions revealed that SRS and LRS were very similar but SES differed from SRS and LRS strongly (p<0.01) in the sum of all amino acids. CONCLUSIONS: The current data indicate that the sum concentrations of all amino acids in serum decrease after the strength exercise session but not after the lactic anaerobic running exercises.     

The effects of acute moderate exercise on leukocyte and lymphocyte subpopulations

The extent and duration of changes in circulating leukocyte and lymphocyte subpopulations, cortisol, and catecholamines were examined in 12 women who walked 45 min at 60% VO2max in a laboratory setting. A two-factor, 2 x 6 design with repeated measures on both factors was utilized. The first factor was condition (exercise and rest), and the second factor was time (six points of measurement over a 24-h period), with treatment order counterbalanced. The 45-min walk, in comparison with rest in a seated position, was associated with a significant but moderate leukocytosis and lymphocytosis immediately following the walk. The leukocytosis was still evident after 3 h of recovery and was primarily due to a neutrophilia. The change in lymphocyte count, relative to baseline levels and the control condition, lasted less than 1.5 h, with an increase in the natural killer (CD16 and/or CD56) and cytotoxic T cell component (CD3 and CD16 and/or CD56) (NKCT) representing approximately two-thirds of the lymphocytosis and T cells (CD5) the other third. A significant decrease in the CD4:CD8 ratio was seen, with cytotoxic/suppressor (CD8) cells increasing and helper/inducer (CD4) cells demonstrating little change in comparison with baseline. This seems to have been due to a subpopulation of CD8 (low density antigen) cells, probably natural killer cells. The 45-min walk had no effect on plasma cortisol and epinephrine levels relative to the rest condition but was associated with a moderate increase in norepinephrine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Occupational exposure to ionizing radiation has no effect on T‐ and B‐cell total counts or percentages of helper,cytotoxic and activated T‐cell subsets in the peripheral circulation of male radiation workers

Purpose: To investigate changes in immune cell subsets in the peripheral circulation of a male population occupationally exposed to ionizing radiation.

Materials and methods: Peripheral blood samples were taken from 194 male workers with cumulative exposures of >200?mSv (mean exposure 331.5?mSv, mean age 51 years) and from a reference population of 131 male workers with cumulative exposures of <27.5?mSv (mean exposure 13.9?mSv, mean age 47 years). Samples were analysed by flow cytometry for T‐ and B‐cell total counts and for the T‐cell subset percentages of CD4⁺ (helper T‐cells), CD8⁺ (cytotoxic T‐cells) and CD3⁺/HLA‐DR⁺ (activated T‐cells).

Results: Comparison of the >200 and <27.5?mSv exposure groups using linear regression analysis showed no statistically significant differences between the two groups for T‐cell total count, B‐cell total count or for percentages of the T‐cell subsets CD4⁺, CD8⁺ or CD3⁺/HLA‐DR⁺ and CD4⁺:CD8⁺. However, statistically significant increases in both T‐ and B‐cell total counts were observed within the two exposure groups and data pooled from both groups when non‐smokers (never and ex‐smokers) were compared with current smokers. For pooled data T‐cell total count increased in smokers by 35% (p=0.0001) and B‐cell total count increased by 37% (p=0.0004).

Conclusions: No significant immunological effects were observed in male radiation workers with cumulative exposures of >200?mSv when compared with a reference population with cumulative exposures of <27.5?mSv, although highly significant increases in both T‐ and B‐cell total counts were observed in smokers compared with non‐smokers.     

Immunological impact of Taekwondo competitions

Immunological changes in elite adolescent female athletes during Taekwondo competitions were investigated on-field. 6 female athletes (16.7 ± 0.8 year-old) volunteered and performed 5 bouts of demonstration Taekwondo competitions simulating real tournaments in intensity, duration, and break-time intervals on the same day. Blood samples were taken before, after the competitions and during the recovery, respectively. Immunological changes and oxidative stress in peripheral blood mononuclear cells were evaluated by flow-cytometry. During the competitions, exercise intensity was 92.2 ± 3.8% (86.1~95.7) of the maximal heart rate. Blood lactate increased immediately after the competitions (p=0.0165) and decreased to baseline during recovery. Intracellular reactive oxygen species (ROS) in the peripheral blood increased continuously during recovery (p<0.05, respectively). Natural killer cells increased immediately after the competitions (p=0.0006), and decreased during recovery. B and T cells increased immediately after the competitions and remained elevated throughout recovery (p<0.05, respectively). CD4/CD8 ratio after the competitions was decreased (p=0.0091) and returned to baseline during recovery. These results suggest that the immunological function of the elite female adolescent athletes could be attenuated after Taekwondo competitions. Further large-scaled Taekwondo studies on immunologic and apoptotic changes related to oxidative stress should be performed for improving and protecting the health of adolescent athletes.     

Immunological changes in response to exercise: influence of age, puberty, and gender

PURPOSE: This study tested the hypothesis that exercise-induced perturbation and recovery of the immune system would vary with age, puberty, and gender in healthy children and adolescents. METHODS: Twelve-year-old girls (YG; N = 14) and boys (YB; N = 20), and 14-yr-old girls (OG; N = 11) and boys (OB; N = 13) cycled for 60 min at 70% VO2max. Blood was collected before, at 30 and 60 min of exercise, and at 30 and 60 min of recovery to measure total leukocytes, leukocyte and lymphocyte subsets, and cytokines. Age and pubertal (Tanner stage) effects within genders and gender effects within age and pubertal groups were determined. RESULTS: Exercise-induced increases in lymphocytes, CD3-CD16+CD56+ counts, and IL-6 were approximately 83, 90, and 390% greater in OG versus YG (P < 0.05). Recovery leukocytosis and neutrophilia were approximately 56 and 35% greater in OB versus YB (P < 0.05). Pubertal stage did not have a statistically significant influence on responses in girls, but the lowest pubertal stage consistently showed smaller changes in lymphocytes and CD3-CD16+CD56+ counts. Recovery neutrophilia was approximately 120% greater in postpubertal boys versus prepubertal or pubertal boys (P < 0.05). Responses of lymphocytes and CD3-CD16+CD56+ counts, respectively, were approximately 120 and 82% greater in OG versus OB (P < 0.05), with no differences between YG and YB. Exercise-induced increases in total leukocytes, lymphocytes, and CD3-CD16+CD56+ counts were at least 35% greater in girls versus boys of similar pubertal status (P < 0.05). Regardless of age, puberty, or gender, IL-8 levels were significantly higher during recovery versus rest (P < 0.05). CONCLUSION: These results highlight the need to control for age, puberty, and gender when interpreting immunologic responses to exercise in a pediatric population.     

Regular tai chi chuan exercise enhances functional mobility and CD4CD25 regulatory T cells

Background

The duration and vigour of physical exercise are widely considered to be critical elements that may positively or negatively affect physical health and immune response.

Objectives

To investigate the effect of a 12 week programme of regular tai chi chuan exercise (TCC) on functional mobility, beliefs about benefits of exercise on physical and psychological health, and immune regulation in middle aged volunteers.

Methods

This quasi‐experimental research design involving one group with testing before and after the programme was conducted to measure the effect of 12 weeks of TCC exercise in 14 men and 23 women from the normal community.

Results

Regular TCC exercise had a highly significant positive effect on functional mobility (p  =  0.001) and beliefs about the health benefits of exercise (p  =  0.013) in the 37 participants. Total white blood cell and red blood cell count did not change significantly, but a highly significant (p<0.001) decrease in monocyte count occurred. A significant (p  =  0.05) increase in the ratio of T helper to suppressor cells (CD4:CD8) was found, along with a significant (p  =  0.015) increase in CD4CD25 regulatory T cells. Production of the regulatory T cell mediators transforming growth factor β and interleukin 10 under specific antigen stimulation (varicella zoster virus) was also significantly increased after this exercise programme.

Conclusions

A 12 week programme of regular TCC exercise enhances functional mobility, personal health expectations, and regulatory T cell function.     

Weight lifting training and left ventricular function in adolescent subjects

AIM: Training during adolescence may influence the myocardium's adaptation. Effects of exercise training on left ventricular function differ depending whether they result from pressure or volume overload. Accordingly, the present study was designed to examine, by echocardiography studies, the effects of endurance versus weight lifting training modes on left ventricular contractility in healthy adolescent boys. METHODS: Sixty healthy adolescent boys were randomly and evenly divided into 3 groups: weightlifting training, run-training, and control. Exercising groups underwent 28-week training programs, 3-4 times a week, 35 min each session. The weight lifting program for consisted of training on 6 dynamic resistive machines at resistance corresponding to 6-repetition maximum. The running program was composed of aerobic exercise training at 65% of their VO(2max). RESULTS: At rest, only in the runners end diastolic volume and end systolic pressure-volume ratio differed significantly (P<0.05) from pre- to post-testing. During post-testing session at peak exercise, runners compared to weightlifters demonstrated improvement respectively in: wall stress (245+/-42 and 290+/-35 103 dyn.cm(2)), end systolic pressure-volume ratio (7.2+/-.7 and 6.4+/-.5 ratio) and ejection fraction (82+/-5% and 76+/-5%). Maximal oxygen uptake (48.2+/-3.2 and 43.8+/-3.5 mL.kg(-1).min(-1)), also improved significantly (P<0.05). Maximal load was significantly (P<0.05) higher in the runners and weight lifters than in the control group with significantly (P<0.05) higher values for the weight lifters than runners. CONCLUSION: This study has showed that in adolescent boys the mode of exercise training leads to significant differences in left ventricular function and contractility, related to differences in volume-after-load relationship and not to fundamental differences in the properties of the myocardium.     

Cytokines and growth factors during and after a wrestling season in adolescent boys

PURPOSE: Brief periods of aerobic exercise training lead to reductions, rather then the expected increases in circulating IGF-I. We hypothesized that intense exercise training in adolescents initially leads to simultaneous increases in proinflammatory cytokines and decreases in activity of the GH/IGF-I axis; and that as exercise training proceeds, levels of proinflammatory cytokines become reduced, and a rebound in IGF-I ensues leading to the higher IGF-I levels. METHOD: To test this, we evaluated the GH/IGF-I axis and levels of inflammatory cytokines (IL-6, TNF-alpha, IL-1beta, IL-1ra), body composition, and fitness in 13 healthy adolescent boys (mean age 15.9 +/- 0.3 yr) over the course of a high-school wrestling season. Subjects were tested preseason, midseason (6 wk), peak season (12-14 wk), and 4 wk postseason. RESULTS: No significant weight loss was noted throughout the season. During the wrestling season (mid and peak) both total (P < 0.046) and free (P < 0.002) IGF-I levels decreased, whereas proinflammatory cytokines (IL-1ra, P < 0.005; IGFBP-1, P < 0.013; and IGFBP-2, P < 0.025) increased. GHBP (P < 0.018) levels also decreased during the season. In the postseason, there were significant increases in GHBP, and free and total IGF-I, whereas proinflammatory cytokines decreased. CONCLUSIONS: An initial catabolic-type hormonal response occurs with intense exercise training in adolescents. This is followed by a rebound in circulating growth factors when the period of heavy training ceases.     

An exploratory study into the effect of exhausting bicycle exercise on endocrine and immune responses in post-menopausal women: relationships between vigour and plasma cortisol concentrations and lymphocyte proliferation following exercise.

It is well-established that bicycle exercise alters the endocrine and immune responses in men, but little information is available for women, especially middle-aged, post-menopausal women. The purpose of our study was to document the endocrine and immune reactivity to exhausting bicycle exercise in post-menopausal women, and to explore whether complaints of fatigue or low vigour are related to these exercise-induced responses. Thirteen healthy post-menopausal women participated in this study. We used a graded exercise protocol to study the kinetics of activation of the endocrine and immune system. We chose to examine hormones related to the hypothalamus-pituitary-adrenal (HPA) system such as adrenocorticotropin hormone (ACTH) and cortisol and hormones related to the pituitary such as prolactin (PRL) and growth hormone (GH). With regard to the immune system, we examined the natural killer (NK) cell activity and pokeweed (PWM)-induced lymphocyte proliferation in addition to changes in peripheral blood cell counts. Our results demonstrate that acute physical stress results in a strong release of ACTH, cortisol, GH and PRL. The bicycle test significantly increased the number of CD3+, CD4+, CD16/56+ (NK cells) and CD8+ cells in our group of post-menopausal women. Interestingly, NK activity did not increase significantly despite an increase in NK cell numbers. PWM-induced lymphocyte proliferation did not change either. In addition, our data support the hypothesis that low vigour in post-menopausal women interferes with the endocrine and immune responses to exhausting exercise. In women with complaints of low vigour we found lower cortisol responses and higher increments in the proliferative capacity of lymphocytes as compared to those with high vigour scores. NK activity was unrelated to exhaustive mood states. These data indicate that endocrine as well as immune system activity changes in response to exhausting exercise in middle-aged, post-menopausal women. In addition, exhaustive mood states may contribute to cortisol responses and function of peripheral immune cells in post-menopausal women following exhausting exercise.