The main neutrophil and neutrophil-related functions may compensate for each other following exercise-a finding from training in university judoists.

In order to clarify the relationship between exercise and neutrophil function, we measured three major neutrophil and neutrophil-related functions, viz. the reactive oxygen species (ROS) production capability and phagocytic activity (PA) of neutrophils and serum opsonic activity (SOA), simultaneously before and after a unified loading exercise under three different sets of conditions. Thirteen female collegiate judoists were examined with a unified exercise loading (2 h) immediately before and after a 64 day training period. Immediately thereafter, the athletes took part in a 6 day intensified training camp, following which the same exercise loading was repeated. Responses from circulating neutrophils were estimated by comparing the two sets of values obtained before and after the two instances of exercise loading. The parameters assessed included neutrophil count, SOA, PA and ROS production capability. ROS production increased after the exercise loading performed immediately before and after the 64 day training period just before the camp, (p < 0.01) but decreased following the exercise loading performed after the camp (p < 0.05). This suggested depressed bacteriocidal capability of the circulating neutrophils. PA decreased after the exercise loading sessions imposed prior to and after the 64 day training period (p < 0.01) but did not change in the loading session after the camp. No changes were seen in SOA produced with the loading exercise either before the 64 day exercise period or before the camp, but increased significantly following the post-camp session (p < 0.05). In conclusion, athletic training-induced changes in immune functional activities of neutrophils, such as ROS production and PA, and neutrophil-related factors, such as SOA, may compensate for each other to maintain the overall integrity of the neutrophil immune function.

Gender differences in the psychological response to weight reduction in judoists.

We examined gender-related differences in the psychological response to weight reduction in 43 judoists. Twenty-two males and 8 females who required weight reduction [weight reduction (WR) group] (the average percentages of weight reduction observed for males and females were 3.4% and 4.9%, respectively), and 5 males and 8 females who did not require weight reduction (non-WR group). The POMS scores were measured before and after weight reduction. The TMD (total mood disturbance) score in POMS significantly increased after weight reduction only in WR group males. In the female WR group, the anger and depression scores decreased after weight reduction, and the pre-value of the TMD score in thisgroup was relatively high. The psychological stress may be caused by anxiety engendered by the overall concept of weight reduction before actual weight reduction in females, whereas in males it may be caused by the actual weight reduction.

Comparison of the amount of pectin in the human terminal ileum with the amount of orally administered pectin.

OBJECTIVE: Dietary fiber by definition is resistant to digestion and absorption in the human small intestine, and it should naturally reach the large intestine. To date, there have been several reports that have examined in vivo how much dietary fiber actually reaches the terminal ileum in human subjects using glucose, with large differences in results. We compared the amount of pectin in the human terminal ileum with that of orally administered pectin. METHODS: Seven healthy male volunteers ages 20 to 27 y were given a test meal containing 4.05 g of pectin. A double-lumen tube was placed in the terminal ileum by using the endoscopic retrograde bowel insertion method, and the ileal contents were aspirated through the tube. Amounts of pectin orally administered and collected from the terminal ileum were estimated as galacturonic acid concentrations (Englyst's method) and were compared with each other. RESULTS: The mean +/- standard deviation amount of pectin collected in the terminal ileum was 3.58 +/- 0.43 g, or 88.4 +/- 10.5% of pectin administered. Further, there were large individual differences in recovery, ranging from 76.8% to 105.1%. CONCLUSIONS: Approximately 90% of ingested pectin was recovered in the terminal ileum in this study. Ten percent may have been degraded by bacteria within the digestive tract, especially the terminal ileum.

Confounding by dietary factors in case-control studies on the efficacy of cancer screening in Japan.

Evaluation of cancer screening using case-control studies is less valid in comparison to randomized controlled trails, due to the intrusion of a possible self-selection bias in the former. The randomized controlled trial approach, however, may be difficult in developed countries where mass cancer screening programs are already being performed nationally. Accordingly, case-control studies are often performed instead of randomized controlled trials. In case-control studies, no reports could be found in the literature using dietary habit, an important influencing factor in carcinogenesis, as an adjusting item. We surveyed nutrition and food intake status through a nutrition survey using the weighing method, and smoking prevalence and alcohol consumption with questionnaires in the general population in northern Japan, in subjects over 30 years of age. We then compared these results among non-participants and participants in cancer screening programs, and evaluated how any differences between the two groups might affect the results of case-control studies. Non-participants had a significantly lower intake of vegetables, carotene, vitamin C, and dietary fiber, which are thought to be beneficial factors in the prevention of carcinogenesis. Non-participants had a significantly higher cigarette smoking prevalence than participants. In relation to the intake of vegetables, a difference between participants and non-participants was evident, as proper adjustment for vegetable intake led to an odds ratio closer to the null value. The value of the odds ratio will probably not decrease, but it might increase when other dietary factors or smoking are taken into consideration.

Effect of 6 months' training on the reactive oxygen species production capacity of neutrophils and serum opsonic activity in judoists.

The effects of long-term training on the production of reactive oxygen species (ROS) from neutrophils and serum opsonic activity (SOA) remain to date unknown. The aim of this study was to evaluate the effect of 6 months training on ROS production and SOA in judoists. Fifty-six judoists were enrolled this study. White blood cell counts, serum creatine kinase (CK), asparate aminotransferase (ASAT), alanine aminotransferase (ALAT), lactate dehydrogenase (LDH) and ROS production from neutrophils, and serum opsonic activity (SOA) using the lucigenin and luminol probes, were measured before and after daily judo exercise (2 h) in March and September. The subjects started their training from March after no exercise for three months, and continued it for 6 months (until September). In March, myogenic enzymes such as CK, ASAT, LDH and neutrophil counts increased and immunoglobulins, complements and SOA decreased after daily judo exercise. Such significant changes were not seen in September. On the other hand, ROS significantly increased after daily judo exercise in both March and September, with no significant difference in the rates of change. In conclusion, 6 month training minimized the changes in SOA as well as muscle enzymes, neutrophil counts, serum immunoglobulins and complements. This could be categorized as a long-term training effect. However, no such change was seen in ROS.

Seasonal changes in mortality rates from main causes of death in Japan (1970--1999).

BACKGROUND: It is well recognized that the season of the year exerts an influence on some diseases and causes of death such as coronary heart diseases, stroke, infectious diseases and so on. METHODS: We evaluated the influence of seasonal changes on diseases and causes of death in Japan using the Japan Vital Statistics from 1970 to 1999 and recorded weather data (mean temperature), by a Fourier decomposition in a log linear regression model. RESULTS: Major influences of seasonal change with the highest rates in winter were seen on the following: the overall causes of death; infectious and parasitic diseases including tuberculosis; respiratory disease, including pneumonia and influenza; heart and cerebrovascular diseases; diabetes; and digestive diseases and accidents. Two peaks were seen in suicides, a large peak in April and a small peak in autumn. Cancer and homicides were little or not at all influenced by seasonality. There was no major difference in changes between the years studied, except for respiratory disease and tuberculosis, which showed a clear reduction in the seasonality effect from 1970 to 1999. CONCLUSIONS: To reduce the overall mortality rate and to prolong life expectancy in Japan, measures must be taken to reduce those mortality rates associated with seasonal differences, especially those causes of death which show a strong correlation with seasonal change: respiratory, heart, cerebrovascular, diabetes and infectious diseases.

A tube-fed liquid formula diet containing dietary fiber increased stool weight in bed-ridden elderly patients.

OBJECTIVE: The number of bedridden elderly patients who need a liquid diet has been increasing. We evaluated the usefulness of a tube-fed liquid diet containing cellulose and oligosaccharide for elderly bedridden patients. METHODS: Twenty-two elderly bedridden patients were given a liquid diet containing cellulose and lafinose for 4 wk. Parameters associated with blood and stool weight were measured during this period. RESULTS: Stool weight increased by 32.0 g in men and 8.8 g in women at 2 wk and remained at these weights up to 4 wk (P < 0.05 before and after 2 wk, 3 wk, and 4 wk in men, and P < 0.05 before and after 3 wk in women). Body weight increased in men (0.5 kg) and women (0.7 kg) 15 d after starting the diet and then remained at these values up to 29 d thereafter, and statistically significant differences were not seen. There were no changes in nutritional parameters such as total protein. CONCLUSION: No significant changes were observed in the general condition of elderly patients, with the exception of a positive increase in fecal weight, by 30-d supplementation of a liquid diet containing cellulose and lafinose.

[Effects of gender-related weight reduction on the physical condition of male and female college judoists].

OBJECTIVE: In order to study the gender-related effects of weight reduction on the physical condition of male and female college judoists during weight reduction periods, we examined changes in anthropometric, nutritional intake and biochemical parameters in 43 male and female college judoists 20 days (pre-weight reduction) before and one day (post-weight reduction) before the game. METHODS: Subjects were divided into two groups. Thirty subjects (22 males, 8 females) who required weight reduction were defined as the weight reduction (WR) group, and the remaining 13 subjects (5 males, 8 females) were defined as the non-reduction (non-WR) group. RESULTS: In both WR groups, anthropometric parameters and nutritional intake significantly decreased after weight reduction compared to the pre-values. The change ratios of nutritional intake during the weight reduction period in the female WR group were higher than those in the male WR group. Serum lipids and electrolytes significantly decreased after the weight reduction compared to the pre-values in both WR groups. In the female WR group, Cr and UA significantly increased after the weight reduction compared to the pre-values. Although it was not significant, Ht increased after the weight reduction compared to the pre-values only in the female WR group. TP, Cr, UA, BUN, CK, LDH and IgA significantly increased after the weight reduction compared to the pre-values in the weight reduction compared to the pre-values in the male WR group. In contrast, in both non-WR groups, these parameters did not change significantly during the research period. CONCLUSIONS: Our findings suggest that nutritional exhaustion and dehydration may be the major effects brought about by energy and fluid restriction in female college judoists during a weight reduction period. On the other hand, in male college judoists undergoing weight reduction, the data suggest that muscle damage and myogenic protein catabolism may be caused chiefly by exercise. These differences may be due to the difference in the method of weight reduction for the different genders, namely, mainly exercise in males and mainly energy and fluid restriction in females.

The fermentation of different dietary fibers is associated with fecal clostridia levels in men.

Only a few reports have compared the fermentation of pectin and cellulose using the hydrogen-breath test, and no studies have examined the relation between the hydrogen breathing pattern and colonic microflora. Using breath-hydrogen measurements, we investigated whether different dietary fibers (DFs) were fermented differently and whether there were individual differences after ingestion of the same DF; we also examined the relation between individual fecal microflora and the fermentation of DF. Results of hydrogen tests in 14 men were compared after they had ingested 20 g of pectin, 20 g of cellulose, or 6 g of lactulose (a DF-like substance). We examined the relation between the breath hydrogen results and the subjects' fecal microflora. We defined significant fermentation (i.e., positive cases) as a continuous rise in hydrogen in the expiratory air of >19 ppm. The subjects were divided into 3 groups according to their hydrogen breath test pattern, i.e., positive for lactulose and pectin (Group LP, n = 4); positive for lactulose alone (Group L, n = 7); and negative for pectin, cellulose, and lactulose (Group N, n = 3). Individual differences were noted in subjects from Group LP and Group L. The detection frequency of lecithinase-negative clostridia was higher in Group LP than in the other groups (P < 0.05), and the detection frequency and the number of lecithinase-positive clostridia were higher in Groups LP and L than in Group N (P < 0.05). These findings suggest that the Clostridium species are associated with hydrogen production. The hydrogen breath test results of DFs depend on both the type of DF and the individual colonic microflora. The amount and constitution of colonic microflora might be predicted by the hydrogen-breath test using different DFs.

A population-based study on defecatory conditions in Japanese subjects: methods for self-evaluation.

We examined the defecatory conditions in a population of Japanese subjects and analyzed the measured parameters as a means for self-evaluation of defecation. Subjects (n=1195) were residents of northern Japan and were all aged over 40 years. The state of defecation and fecal characteristics were assessed with regard to nine parameters including "self-reported bowel habit" and "bowel movement frequency." Logistic regression analysis was carried out to analyze the association between the complaint of constipation and other eight parameters. A higher tendency for constipation was noted in women than in men. The highest value of the odds ratio was "bowel movement frequency"; especially the value "once per three days or more" was noted in both genders (odds ratio: 13.38 and 42.46 in men and women, respectively). In addition, "stool appearance", "length of time for bowel movement", "straining after bowel movement", "alternating diarrhea/constipation/disorder" and "travel-related changes in bowel movements" were significantly related with the complaint of constipation ("self-reported bowel habits") in both genders. In conclusion, the study elucidated that personal and subjective evaluation of bowel habits in normal subjects consisted of various factors under the heading of "bowel movement frequency".

Nutritional effects of supplementing liquid-formula diet with dietary fiber on elderly bed-ridden patients.

In the past few decades, the number of bed-ridden elderly patients has been increasing. This group of patients is frequently fed with a liquid formula diet. The aim of this study was to evaluate the usefulness of a liquid formula diet containing dietary fiber (DF) for elderly bed-ridden patients. Eighteen elderly, bed-ridden patients were given L-3 Fiber, a DF-containing liquid formula diet (DF-LFD), for 4 weeks, while a number of parameters were monitored, including serum levels of total cholesterol, triglyceride, total protein, creatinine, uric acid, glucose, sodium, potassium, and calcium, urine protein/sugar, and defecation frequency. Total protein, albumin and total cholesterol significantly increased following the administration of the DF-LFD, associated with an average increase in body weight of 1.94 kg (5.0%). Defecation frequency significantly increased one week after DF-LFD administration was started, but this effect was transient. Although a few patients complained of nausea, vomiting or abdominal pain, no severe side effects were seen. In conclusion, DF-LFD supplementation appears to be beneficial for elderly bed-ridden patients, and can increase nutritional-related parameters, such as body weight, total protein, albumin and total cholesterol, without severe side effects.

Adverse effects of energy restriction on myogenic enzymes in judoists.

In this study, we examined the effects of weight reduction by restricting energy intake on muscle function and serum concentrations of myogenic enzymes in judoists. Twenty-seven male judoists aged 19.3 +/- 0.6 years (mean +/- s) were divided into three groups based on the extent of body weight reduction: high weight reduction (height 1.70 +/- 0.05 m, body mass 78.5 +/- 13.6 kg), low weight reduction (height 1.70 +/- 0.05 m, body mass 80.7 +/- 13.1 kg) and a group that maintained body weight while continuing to perform exercise training (height 1.78 +/- 0.07 m, body mass 78.7 +/- 8.8 kg). Body composition, blood biochemistry, energy intake and anaerobic power were assessed on four occasions: 20 days (baseline data), 4 days and 1 day before and 7 days after competition. Compared with baseline, body mass and fat-free mass were significantly lower 1 day before competition in the high and low weight reduction groups (both P < 0.01); these changes persisted for 7 days after competition in the high weight reduction group. Serum creatine kinase was significantly elevated 1 day before competition in all groups (all P < 0.05), and remained higher 7 days after competition in both the high and low weight reduction groups. Compared with baseline, maximal anaerobic power was significantly lower 1 day before competition only in the high weight reduction group (P < 0.01). Our results suggest that energy restriction in addition to intense exercise training before major competition has an adverse effect on anaerobic power and elevates serum creatine kinase concentration, leading to an impairment of muscular function and an increased susceptibility of muscle tissue to injury.

Firm measures are required to effect any significant decrease in the Japanese age-adjusted mortality rate from malignant neoplasms for the 21st century.

The Japanese have the longest lifespan worldwide, but this has been mostly due to reductions in the mortality rates from diseases other than malignant neoplasms. Changes in the age-adjusted mortality rates (AMRs) for malignant neoplasms in Japan from 1950 to 2000 are analyzed to elucidate the overall trend. The overall AMRs for all malignant neoplasms in men increased from 1950 to 2000, and decreased slowly in women during the same period. Changes since 1990 have been small in both genders, but show a hopeful trend towards a decrease in the total AMR since 1995. These trends reflect a balance between the decreased AMR from gastric (both male and female) and uterine cancers and increases in many other malignant neoplasms. However, in the period 1990-2000, the decrease in the AMR from gastric and uterine cancers has shown a trend towards leveling off. Therefore, improving the trend towards reductions in cancer incidence and mortality in the 21st century and beyond will depend on achieving changes in other cancer sites, which can only be realized through the twofold approach of preventative medicine and research as well as improvements in the levels of diagnosis and therapy. Much more emphasis must therefore be placed on primary prevention, in particular on anti-smoking campaigns, as well as stepping-up research into the etiology of, and novel treatments for other malignant neoplasms, especially colorectal and breast cancers.

The prevention of colon carcinogenesis in rats by dietary cellulose is greater than the promotive effect of dietary lard as assessed by repeated endoscopic observation.

We developed a method which we used in the current study to observe the rat colon endoscopically. Our goal was to evaluate the entire course in the development of experimental large bowel tumors through serial observations in the same rat. We compared the effects of dietary lard and cellulose on rat colon tumorigenesis in a 2 x 3 factorial design. Sprague-Dawley rats (n = 90) were divided into 6 diet groups: rats were fed a diet without cellulose that contained 5, 10, and 15 g/100 g lard, or diets containing 15% cellulose diet (15 g cellulose/100 g diet) and the same concentrations of lard. The development of large bowel tumors induced by the administration of 1,2-dimethylhydrazine (25 mg/kg body weight) for 19 wk was examined endoscopically. Tumor induction rates in the 15% cellulose groups were lower than in the 0% cellulose groups (P = 0.008), independent of the lard concentration. These results suggest that the preventive effect of cellulose against large bowel tumorigenesis is greater than the promotive effect of fat under the current experimental conditions.

Defoliation effects on the community structure of arbuscular mycorrhizal fungi based on 18S rDNA sequences.

The effects of defoliation on arbuscular mycorrhizal (AM) associations in the field were investigated in terms of the community structure of AM fungi colonizing roots of grassland plants; the carbohydrate balance of the host plants was also determined. We focused on two plant species dominating Japanese native grasslands: the grazing-intolerant species Miscanthus sinensis and the grazing-tolerant species Zoysia japonica. Community structures of AM fungi were determined from 18S rRNA gene sequences. The dominant fungal group in both plant species was the Glomus clade, which was classified into several phylogenetic groups based on genetic distances and topology. In Miscanthus roots, the Glomus-Ab, Glomus-Ac, and Glomus-Ad groups were detected almost equally. In Zoysia roots, the Glomus-Ab group was dominant. Defoliation effects on the community structure of AM fungi differed between the plant species. In Miscanthus roots, the percentage of root length colonized (%RLC) by the Glomus-Ac and Glomus-Ad groups was significantly reduced by defoliation treatment. On the other hand, AM fungal group composition in Zoysia roots was unaffected by defoliation except on the last sampling date. Decreased %RLC by Glomus-Ac and Glomus-Ad coincided with decreased non-structural carbohydrate (NSC) levels in host plants; also, significant positive correlations were found between the %RLC and some NSC levels. On the other hand, the %RLC by Glomus-Ab in both plant species was unaffected by the NSC level. These results suggest that AM fungal groups have different carbohydrate requirements from host plants.

Exhaustive exercise and type-1/type-2 cytokine balance with special focus on interleukin-12 p40/p70.

It is known that interleukin (IL)-12 p70 promotes the differentiation of type-1 helper T (Th1) cells, which produce type-1 cytokines such as IL-2 and interferon (IFN), thereby supporting cellular immunity, whereas IL-12 p40 acts as an antagonist of IL-12 p70. In contrast, IL-4 and IL-6 promote the differentiation of Th2 cells, which produce type-2 cytokines IL-4, IL-6 and IL-10, induce humoral immunity and are involved in allergic reactions. Exhaustive exercise causes the suppression of T lymphocyte activity while asthmatic and allergic diseases are subclinically more prevalent in athletes. One of the mechanisms behind these observations might be a lower type-1 and higher type-2 cytokine balance, which we previously demonstrated to occur after exhaustive exercise. In the present study, we investigated the type-1/type-2 cytokine balance by measuring plasma concentrations of IL-2, IL-4, IL-5, IL-10, tumor necrosis factor (TNF)-alpha and IFN-gamma with microparticle-based flow cytometric technology. IL-5, IL-6 and IL-13 were measured by enzyme-linked immunosorbent assay (ELISA). IL-12 p40 and p70 were measured separately, also by ELISA. Plasma IL-12 p40 concentration rose significantly after maximal exercise and to an even greater extent after a marathon race. Conversely, plasma IL-12 p70 could not be detected even using two different assays. The marathon race caused a marked increase in the plasma concentrations of IL-6 and IL-10. Their responses were correlated (r = 0.78, p < 0.01), indicating that IL-6 is an inducer of IL-10, and may partly induce the type-1 < type-2 cytokine balance. With the exception of one study involving maximal exercise, other studies have failed to show any change in circulating IL-12 concentration with exercise. The present study demonstrated that IL-12 p40 was present in excess of p70 especially after exercise. This may be one of the mechanisms behind several phenomena including cellular immunosuppression, an increase in the relative proportion of type-2 cytokines following exhaustive exercise, and the higher incidence of infections and allergic disorders in regularly exercising endurance athletes.

A competitive marathon race decreases neutrophil functions in athletes.

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.

Ecabet sodium attenuates reactive oxygen species produced by neutrophils after priming with bacterial lipopolysaccharides.

The pathogenic roles of reactive oxygen species (ROS) have been implicated in ulcerative colitis (UC). The aim of this study was to examine the effects of ecabet sodium on ROS produced by human neutrophils, particularly after being primed by bacterial lipopolysaccharides (LPS). Neutrophils were isolated from six healthy volunteers. Each well of a 96-well microplate received neutrophil suspension (1.0 x 10(5) cells) and the plates were incubated at 37 degrees C for 30 min with or without E. coli LPS (f.c. 0.001 ng/ micro L). Ecabet sodium (f.c. 0-5.0 mg/mL) was added before starting or after finishing the incubation. Neutrophils were stimulated by opsonized zymosan (OZ; 1.0 mg/mL) or calcium ionophore (A21837; 0.3 micro mol/L) and luminol-dependent chemiluminescence response was measured using a Lumi Box H-1000. Ecabet sodium attenuated ROS production at a concentration of 5.0 mg/mL (p < 0.05) in LPS-primed neutrophils. However, attenuating effects were not significantly different when ecabet sodium was added before or after the incubation with E. coli LPS. Ecabet sodium may have some attenuating effects on ROS produced by human neutrophils even after neutrophils are primed by bacterial LPS. These results may explain, in part, the therapeutic effects of ecabet sodium for UC.

The acute response of neutrophil function to a bout of judo training.

Intensive exercise training decreases neutrophil functions in athletes. However, no studies to date have investigated the effect of irregular-interval training, such as is associated with judo training programmes, on neutrophil functions. The purpose of this study was to examine such effects. Thirty-seven male college judoists participated in this study. Neutrophil oxidative burst activity, phagocytic activity and expression of CD11b and CD16 per cell were measured by fl ow cytometry before and after judo training. Total neutrophil counts increased significantly from 2.98 +/- 0.82 to 7.95 +/- 1.80 x 10(3)/ microL (p < 0.001). The proportion of neutrophils producing reactive oxygen species (ROS) was increased significantly (p < 0.001). On the other hand, the phagocytic activity decreased after training, as shown by a decrease in the amount of ingested opsonized zymosan per cell (p < 0.001), possibly as a compensatory effect for the increased numbers of ROS-producing neutrophils. Expression of CD11b and CD16 per cell decreased by 20% and 30%, respectively, after judo training. In conclusion, judo training induced a decrease in phagocytic activity through the lowered expression of CD11b and CD16 on the surface of neutrophils, and increased the oxidative burst activity of neutrophils.

Effects of weight reduction on neutrophil phagocytic activity and oxidative burst activity in female judoists.

This study investigated the effects of short-term weight reduction on neutrophil functions in female judoists. Sixteen actively competing female judoists were divided into two groups. Eight who required weight reduction were defined as the weight reduction group, and the remaining eight were used as the control. Blood samples were taken before, immediately after and 8 days after the match. Phagocytic activity and oxidative burst activity of neutrophils were measured by flow cytometry. In the weight reduction group, the phagocytic activity per cell decreased significantly at the end of weight reduction compared with the control group. The rate of neutrophils producing reactive oxygen species and the oxidative burst activity per cell increased significantly at the end of weight reduction in both the control and the weight reduction groups. We concluded that weight reduction, consisting of both intense exercise and energy restriction, might possibly cause both an increase in oxidative burst activity and decrease in neutrophil phagocytic activity in female judoists. However, although exercise increased oxidative burst activity, it did not affect neutrophil phagocytic activity alone. Therefore, to avoid this problem, female judoists are recommended to keep their weight within those limits determined by their class, and which can be reduced by exercise.