Combat Athletes Research Articles

Trunk Muscle Aerobic Metabolism Responses in Endurance Athletes, Combat Athletes and Untrained Men

This study investigated aerobic metabolism responses in trunk muscles during a prolonged trunk extension exercise in athletes and untrained young men. The aim was to analyze the adaptations induced by 2 types of sports: one involving intensive use of trunk muscles (i. e., judo), and one known to induce high aerobic capacity in the whole body (i. e., cycling). Eleven judokas, 10 cyclists and 9 healthy untrained young men performed trunk extension exercises on an isokinetic dynamometer. During the first session, muscle strength was assessed during maximal trunk extension. During a second session, a 5-min exercise was performed to investigate aerobic responses with regard to trunk muscles. The near infrared spectroscopy technique and a gas exchange analyzer were used continuously to evaluate mechanical efficiency, V̇O2 on-set kinetics, trunk muscle deoxygenation and blood volume. Judokas showed greater trunk strength and mechanical efficiency (p<0.05). Cyclists presented faster V̇O2 on-set kinetics (p<0.05) and greater muscle deoxygenation and blood volume compared to untrained men (p<0.001). These results suggest that practicing judo improves trunk extension efficiency whereas cycling accelerates aerobic pathways and enhances microvascular responses to trunk extension exercise. Sport practice improves aerobic metabolism responses in trunk extensor muscles differently, according to the training specificities.

Характеристика фізичних якостей єдиноборців-ветеранів різних вікових груп

Human physical condition, physical qualities and motor skills tend to change significantly with age. There are significant changes in the coordination of movements as well: the accuracy of their execution decreases, the pace and mobility slow down, the reaction speed diminishes, the rate of new motor action development decreases. However, despite large reflection of these aspects in literary sources, it should be noted that there are contradictory opinions on the issues of norms and, especially, the modes of motor activity, as well as the regulation of physical loads, mainly aimed at maintaining the motor coordination abilities of athletes-masters. Objective. To determine changes in the level of physical qualities of single combat athletes of different age groups under the influence of training sessions. Methods. To determine the level of manifestation of physical qualities general preparatory and special exercises performed by single combat athletes were used, who trained three times a week and participated in competitions in accordance with adopted in martial arts age groups. The results of tests were taken from the protocols of control tests at the beginning of the competition period as the most commonly used in determining the level of development of physical qualities in single combat fighters and the most accessible to perform by athletes of different ages. Results. The conducted studies allowed to establish the dynamics of the manifestation of physical qualities of single combat masters in different age periods of veterans’ sports. As a result of the study, it was found that after the cessation of active sports practicing, the level of physical qualities is gradually reduced, but in the studied age periods has occured unevenly. The obtained results indicate gradual decrease of physical fitness indices during the period of studies, which is connected in some cases with an increase in body weight and gradual decrease of the motor potential of athletes-masters.

Association of serotoninergic pathway gene variants with elite athletic status in the Polish population

ABSTRACTGenetic factors are known to influence sport performance. The aim of the present study was to assess genetic variants in genes coding for proteins potentially modulating activity of brain emotion centres in a group of 621 elite athletes (212 endurance, 183 power and 226 combat athletes) and 672 sedentary controls. Ten statistically significant variants were identified in genes encoding elements of serotoninergic, catecholaminergic and hypothalamic-pituitary-adrenal systems in different sport groups. Of those the rs860573 variant in the FEV gene coding for transcription factor exclusively expressed in neurons of the central serotonin system is the only one whose frequency significantly differentiates all the groups of athletes studied, regardless of discipline, from the controls (p = 0.000026). Our results support the hypothesis that genetic variants potentially affecting mental processes and emotions, particularly in the serotonergic pathway, also influence the predispositions to athletic performance.

Differences in the Perceived Attractiveness of Non-contact and Combative Athletes' Facial Pictures

Abstract Female mating strategies and partner preferences are influenced by many factors. Depending on the life context, the preference for either a long-term or a short-term relationship, the willingness to have off-spring, or the current fertility conditions can be key factors. Differences can largely be traced to the perception of physical masculinity and the ability to provide and raise offspring. This study seeks to obtain data that will help to describe changes in the female perception of the attractiveness of facial photographs of male elite golfers (non-contact sport) and MMA fighters (combative sport) in connection with the following factors: age, sexual activity/passivity, use of hormonal contraceptives, duration of actual relation-ship, and number of children. Data for this study were collected using an anonymous questionnaire that included photos of the athletes in a random order and a 1-10 rating scale (10 indicating the most attractive). The research sample consisted of 1,035 female participants. The statistical significance was analyzed using the Kruskal-Wallis and Mann-Whitney U tests, Eta2, and Cohen's d for the average ratings of the contact and non-contact athletes. The female participants slightly preferred the golfers’ pictures. This preference grew significantly with age and number of children. A possible explanation for these results may be the participants’ decreasing fertility or the willingness to have another child in the Czech socio-culture. In such cases, the strong masculine features typical of combative athletes could be less important. In contrast to some earlier findings, contraceptive use did not affect the perception of male attractiveness compared to the entire sample's average ratings, furthermore, neither did sexual activity/passivity.

Влияние профилактической иммунотерапии на показатели клеточного иммунитета спортсменов-единоборцев высокого класса в зависимости от уровня спортивных достижений

Objective: to evaluatethe preventive immunotherapy's (PIT) influence on indicators of cellular immunity of highly qualified combat athletes, depending on the level of sporting achievements. Materials and methods: research included 79 sportsmen with average age of 25,2 years, average weight 76,9 kg, sports experience no less than 10 years and sports rank no less than master of sports. Participants were stratified by the level of achievements in sports. The group 1 with highest level of achievements consisted of 31 sportsmen, each of who earned victory or a prize place on biggest international competitions (such as championships of Europe, World and Olympic Games). Remaining 48 participants didn't have such achievements, but theywere a part of national team (Group 2). PIT included probiotic - Fervital, a complex preparation of omega 3-6-9 fatty acids, vitamin-mineral complex - the Alphabet-biorhythm; antioxidant complex - Ubigold Q10 (coenzyme Q + vitamin E); antihypoxant - Hypoxen; sedative - Novo-Passit; adaptogenic drug - Gerimax Ginseng; polyenzyme complex - Wobenzym. Results: there was a great balance of cellular immunity in the group 1 before the PIT due to the higher content of CD4 + and CD19 + cells. A statistically significant increase in the relative content of CD3 + and CD8 + cells and a decrease in the relative and absolute content of CD16 + cells was detected against the background of PIT in the group l. But the group 2, on the contrary, showed an increase in the relative and absolute content of CD16 + cells. Conclusions: the obtained results showed a different reaction in the both groups to the conducted preventive immunotherapy, which, apparently, was due to the initial difference in the biochemical, genetic, psychological potential of athletes of these two groups.

Prevalence of Rapid Weight Loss Practices and Their Profiles Among Non-Elite Combat Athletes in Kuching, East Malaysia

Abstract Introduction. Rapid Weight Loss (RWL) is a common practice in combat sports where weight is classified to ensure equitable competition in terms of strength and agility. This study aimed to investigate the profiles of non-elite combat athletes and their RWL practices. Material and methods . This research was a cross-sectional study conducted in Kuching, Sarawak. Data were collected using a validated self-administered dual-language questionnaire. Results. A total of 65 respondents participated in the study; two-thirds were male, and the majority were taekwondo athletes. About 66% of the respondents reported to have practised rapid weight loss, with average weight loss of 3.4 kg (SD = 1.90) and highest weight loss of 4.9 kg (SD = 3.16). The most common RWL methods used were exercising more (69.8%), gradual dieting (51.1%), and training in heated rooms (20.8%). Physical trainers and training colleagues were rated as persons having the most influence on the use of RWL by the respondents. The perceived adverse effects which were mentioned the most frequently by the respondents were fatigue (69.2%), decreased vigour (50.8%), and muscle cramps (46.2%). As for the type of combat sport practised, muay thai and jiu jitsu had the highest number of respondents who used RWL. There were significant differences in RWL practices depending on the influences of training colleagues, physicians/doctors, physical trainers, parents, dieticians, and former athletes as well as perceived adverse effects of RWL. Conclusions . The findings of the current study were observed to be similar to those of research involving elite combat sport athletes where the prevalence of RWL was reasonably high, with similar characteristics. A proper regulatory programme should be put in place to assist both the athletes and their coaches/trainers in implementing proper weight control.

Особливості змін психофізіологічних показників спортсменів, що займаються рукопашним боєм з повним контактом з супротивником, під впливом тренувального навантаження

Особливості змін психофізіологічних показників спортсменів, що займаються рукопашним боєм з повним контактом з супротивником, під впливом тренувального навантаження

Associations between the dopamine D4 receptor gene polymorphisms and personality traits in elite athletes.

Personality traits and temperament may affect sports performance. Previous studies suggest that dopamine may play an important role in behavior regulation and physical exercise performance. The aim of this study is to determine associations between dopamine D4 receptor gene (DRD4 Ex3) polymorphisms and personality traits (such as neuroticism, extraversion, openness, agreeability and conscientiousness) in elite combat athletes. A total of 302 physically active, unrelated, self-reported Caucasian participants were recruited for this study. The participants consisted of 200 elite male combat athletes and 102 healthy male participants (control group). For personality trait measurements, the NEO Five-Factor Personality Inventory (NEO-FFI) and the State-Trait Anxiety Inventory questionnaires were used. For the genetic assays, blood was collected and all samples were genotyped using the real-time PCR method. A 2 x 3 factorial ANOVA revealed statistically significant differences on the Openness NEO Five Factor Inventory scale for both examined factors, i.e. sport status and genetics DTD4 Ex3. Combat athletes achieved higher scores on the Conscientiousness NEO-FFI scale when compared to controls (7.18 vs 5.98). On the other hand, combat athletes scored lower on the Openness scale in comparison with control group (4.42 vs. 4.63). Subjects with the DRD4 Ex3 s/s genotype had lower results on the openness scale in comparison with participants with the DRD4 Ex3 s/1 genotype (4.01 vs. 4.57) and higher DRD4 Ex3 1/1 genotype (4,01 vs. 3,50). In conclusion, we found an association between the dopamine D4 receptor gene in variable number tandem repeat (VNTR) polymorphisms and athletic status for two NEO-FFI factors: Openness and Conscientiousness. The DRD4 exon 3 polymorphism may be associated with the selected personality traits in combat athletes, thereby modulating athletes’ predisposition to participate in high risk sports.

Effects of a Six-Week Strength and Power Training Program on Punching and Kicking Impact Power in Amateur Male Combat Athletes: A Pilot Study

The purpose of the present study was to examine the effect of a six-week strength and power training program, on striking impact power in amateur male combat athletes. A convenience sample of 16 amateur male combat athletes with at least two years combat training experience were assigned to either a strength and power training program (SPT, n=10) or control group (CT, n=6). Both groups performed three weekly combat training sessions for six weeks. The SPT group performed two sixty-minute SPT sessions in addition to usual combat training. The following variables: leadhand jab, rear-hand cross, front kick and roundhouse kick mean impact power, vertical jump height, and five-repetition maximum (5RM) half-squat and bench press, were measured using standard protocols at baseline and after six weeks. Magnitude-based inferences (Cohen’s d (d) ± 90% CI) revealed likely beneficial effects of SPT on cross punch (d=0.69 ±0.76), roundhouse kick power (d=0.86 ± 0.83), and vertical jump (d=0.53 ± 0.66). Benefits of usual combat training were unclear for all measured parameters. When between-group changes across the six-week period were compared SPT demonstrated likely benefits for cross-punch (d=0.75 ± 0.80) and 5RM half-squat (d=0.81 ±0.78) compared to usual combat training. These data suggest the addition of SPT to combat training may have a beneficial effect on cross-punch impact power and 5RM half-squat strength in amateur male combat athletes.

Collecting Health and Exposure Data in Australian Olympic Combat Sports: Feasibility Study Utilizing an Electronic System.

BackgroundElectronic methods are increasingly being used to manage health-related data among sporting populations. Collection of such data permits the analysis of injury and illness trends, improves early detection of injuries and illnesses, collectively referred to as health problems, and provides evidence to inform prevention strategies. The Athlete Management System (AMS) has been employed across a range of sports to monitor health. Australian combat athletes train across the country without dedicated national medical or sports science teams to monitor and advocate for their health. Employing a Web-based system, such as the AMS, may provide an avenue to increase the visibility of health problems experienced by combat athletes and deliver key information to stakeholders detailing where prevention programs may be targeted.ObjectiveThe objectives of this paper are to (1) report on the feasibility of utilizing the AMS to collect longitudinal injury and illness data of combat sports athletes and (2) describe the type, location, severity, and recurrence of injuries and illnesses that the cohort of athletes experience across a 12-week period.MethodsWe invited 26 elite and developing athletes from 4 Olympic combat sports (boxing, judo, taekwondo, and wrestling) to participate in this study. Engagement with the AMS was measured, and collected health problems (injuries or illnesses) were coded using the Orchard Sports Injury Classification System (version 10.1) and International Classification of Primary Care (version 2).ResultsDespite >160 contacts, athlete engagement with online tools was poor, with only 13% compliance across the 12-week period. No taekwondo or wrestling athletes were compliant. Despite low overall engagement, a large number of injuries or illness were recorded across 11 athletes who entered data—22 unique injuries, 8 unique illnesses, 30 recurrent injuries, and 2 recurrent illnesses. The most frequent injuries were to the knee in boxing (n=41) and thigh in judo (n=9). In this cohort, judo players experienced more severe, but less frequent, injuries than boxers, yet judo players sustained more illnesses than boxers. In 97.0% (126/130) of cases, athletes in this cohort continued to train irrespective of their health problems.ConclusionsAmong athletes who reported injuries, many reported multiple conditions, indicating a need for health monitoring in Australian combat sports. A number of factors may have influenced engagement with the AMS, including access to the internet, the design of the system, coach views on the system, previous experiences with the system, and the existing culture within Australian combat sports. To increase engagement, there may be a requirement for sports staff to provide relevant feedback on data entered into the system. Until the barriers are addressed, it is not feasible to implement the system in its current form across a larger cohort of combat athletes.

ФИЗИОЛОГИЧЕСКИЕ МЕХАНИЗМЫ ГЕНЕТИЧЕСКОЙ РЕГУЛЯЦИИ ФУНКЦИОНАЛЬНОЙ РАБОТОСПОСОБНОСТИ И ВЫНОСЛИВОСТИ ОРГАНИЗМА СПОРТСМЕНОВ-ЕДИНОБОРЦЕВ ПРИ АДАПТАЦИИ К ФИЗИЧЕСКОЙ НАГРУЗКЕ

Aim. The article deals with studying physiological mechanisms of the polymorphic variants of genes H1F1A Pro/Ser, influencing adaptation in combat athletes during physical load. Materials and methods. We studied combat athletes of various ranks from a sports school in Chelyabinsk: athletes of 1st, 2nd, and 3rd ranks (youth ranking) – 23 persons (control group); athletes of 1st, 2nd, and 3rd ranks (adult ranking) – 27 persons (experimental group 1); professional athletes (Candidate for Master of Sport and Master of Sport) – 26 persons (experimental group 2). We studied polymorphic variants of genes, regulating the cardiovascular system, performance, and endurance in combat athletes (HIF1A Pro/Ser). We performed the amplification of the fragments of genomic DNA, containing polymorphic parts, by polymerase chain reaction (PCR) in iQ5 Bio-Rad (the USA) and GeneAmp PCR System 9700 (Applied Biosystems, the USA) amplifiers. Primers were synthesized by Evrogen company (Russia). Results. During the typing of Pro582Ser polymorphism of H1F1A gene, we revealed three genotypes and two alleles. Only in the experimental group 2, H1F1A *Ser/Ser genotype has a frequency of 76.47%; for the same sample, the frequency of H1F1*Ser allele is 87.2% and of H1F1A*Pro allele is 12.75%. Conclusion. We performed the analysis of the polymorphic loci of molecular genetic markers (HIF1A Ser/Ser, HIF1A*Ser). This allowed us to determine the cardiorespiratory and aerobic glycolytic system performance in wrestlers during their adaptation to physical load. Our analysis revealed that there is a direct correlation between the high level of integral functional preparedness in combat athletes and athletes’ gene alleles (HIF1A Ser/Ser, HIF1A*Ser). To achieve success in combat sports, the optimal number of these alleles is from 4 to 6.

Collaboration Needed on Human Performance Optimization for Combat Athletes

Collaboration Needed on Human Performance Optimization for Combat Athletes

ФОРМИРОВАНИЕ АДАПТАЦИИ СПОРТСМЕНОВ ВЫСОКОЙ КВАЛИФИКАЦИИ К ФИЗИЧЕСКИМ НАГРУЗКАМ РАЗНЫХ ВИДОВ СПОРТА ПУТЕМ ИЗМЕНЕНИЯ СООТНОШЕНИЯ КОМПОНЕНТОВ ТЕЛА

Aim. The aim of this article is to establish the model values of body composition for professional combat athletes. Materials and methods. In the morning we measured body composition using Tanita BC-418 body analyzer. The study involved 3 groups of professional male athletes (Candidates for Master of Sport, Masters of Sport; body weight 60–75 kg) from various combat sports: kickboxing (n = 23), sambo and judo (n = 25), taekwondo (n = 22). Results. In judo and sambo athletes we revealed greater relative amount of adipose tissue (about 12%), while in kickboxers and taekwondo athletes its values were within 7–9%. Taekwondo athletes demonstrated the lowest values of adipose tissue in arms, while its values in legs were higher than in wrestlers. The lowest limbs muscle mass was registered in wrestlers, taekwondo athletes demonstrated higher muscle mass in legs, and both kickboxers and taekwondo athletes had higher muscle mass in arms. The difference between muscle mass in the trunk and muscle mass in legs was about 5 kg. Together with the data obtained using Box-Whiskers/Multiple graphic construction, where the median and 25–75 percentiles were almost identical, this proves that there are some model values for the body composition of professional athletes. Correlation analysis revealed that there was no correlation between muscle mass and adipose tissue in the limbs of wrestlers and kickboxers, while in taekwondo athletes we registered 3 correlations (р ≤ 0.05) mostly connected with arm muscles. Conclusion. We obtained body composition models for wrestlers, kickboxers and taekwondo athletes, which can allow us to individualize training process and forecast sport performance.

Sexual Behaviour of Combative Athletes – Is There a Greater Risk?

Abstract Athletes are often associated with a greater degree of risk behaviour. It also includes potentially dangerous sexual habits and behaviour, among other things. This study deals with sexual habits and behaviour of combative athletes. The research sample (n-65) consists of representatives of various combat sports and these representatives are categorized into three groups: international (n-15), national (n-28), and regional competitors (n-22). Data were collected through the medium of a questionnaire which allowed us to compare results with sexual behaviour of Czech population over last 20 years. Athletes comprised in this study are more sexually active, have more sexual partners over the life, and tend to have various, risk sexual behaviour more likely than common Czech population. This phenomenon is more significant in elite athletes. We believe this could be affected by access to short-term relationships and by the awareness of athletes that they are attractive to women. In the light of these findings, we suggest to increase prevention of risky sexual behaviour for athletes in masculine sports.

Validity and Reliability of the 30-s Continuous Jump for Anaerobic Power and Capacity Assessment in Combat Sport.

Cycling test such Wingate anaerobic test (WAnT) is used to measure anaerobic power (AP), but not anaerobic capacity (AC, i.e., the metabolic energy demand). However, in sports that do not involve cycling movements (Karate), the continuous jump for 30 s (vertical jumps for 30 s) has been extensively used to measure anaerobic performance in all young athletes. Limited information’s are available concerning its validity and reliability especially in children. As such, the current study aimed to test validity and reliability of a continuous jumps test (the CJ30s), using WAnT as a reference. Thirteen female Karate kids (age: 11.07 ± 1.32 years; mass: 41.76 ± 15.32 kg; height: 152 ± 11.52 cm; training experience: 4.38 ± 2.14 years) were tested on three separate sessions. The first and second sessions were used to assess the reliability using Intra-class correlation coefficient (ICC) of CJ30s, whereas on the third session WAnT was administered. Following CJ30s and WAnT, we assessed AP (1/CJ30s, as jump height [JH], fatigue index [FI], and blood lactate [BL]; 2/WAnT, as mechanical power [P], FI, and BL) and AC as the excess post-exercise oxygen consumption (EPOC). Large/highly significant correlations were found between CJ30s and WAnT EPOCs (r = 0.730, P = 0.003), and BLs (r = 0.713, P = 0.009). Moderate/significant correlations were found between CJ30s and WAnT FIs (r = 0.640, P = 0.014), CJ30s first four jumps mean JH and WAnT peak P (r = 0.572, P = 0.032), and CJ30s mean JH and WAnT mean P (r = 0.589, P = 0.021). CJ30s showed excellent and moderate reliability (ICC) for AP (maximal JH 0.884, mean JH 0.742, FI 0.657, BL 0.653) and AC (EPOC 0.788), respectively. Correlations observed especially in terms of AC between CJ30s and WAnT provide evidence that former may adequately assess anaerobic performance for the young combat athlete. CJ30 is a reliable test and allow an easy assessment of AP and AC in karate children.

Nutritional Status and Physical Development of High-Performance Combat Athletes in Lithuania

Background. Adequate nutrition is inseparable from athletes’ optimal physical development and achieved sports performance. Preparing for the Olympic Games athletes’ nutrition must meet certain requirements. Only under appropriate nutrition conditions athletes are enabled to maximize their adaptation to physical loads. Hypothesis: nutrition of Lithuanian high performance athletes in combat sports is adequate. Research aim was to assess nutrition profile and physical development of Lithuanian high performance athletes in combat sports. Methods. During the competition preparation period of 2012, the actual diets of Lithuanian elite boxers (n = 14), and the Greco-Roman wrestlers (n = 29) were tested and evaluated. Body composition parameters and physical development of combat athletes were assessed using BIA tetra - polar electrode method. Athletes’ actual diets were established using the actual dietary survey method. Results. Muscle and fat mass indexes of boxers and Greco-Roman wrestlers, 7.5 ± 3.8 and 5.4 ± 2.0 respectively, show that effective complex preparation measures ensure optimal body condition status of athletes. Nevertheless, the diets of combat sport athletes do not meet the requirements: irrational use of proteins, not enough carbohydrates and polyunsaturated fatty acids, including omega-6 and omega-3 fatty acids, vitamins D, B 1 , PP, minerals, manganese, zinc, calcium and copper, too much intake of fat, saturated fatty acids and cholesterol. Conclusion. The existing diets of Lithuanian elite combat sports athletes cannot ensure their maximal adaptation to physical loads and must be optimized, individualized and adjusted, adding dietary supplements with extra carbohydrates, essential fatty acids, vitamins, minerals, and in exceptional cases, nutritional supplements with essential amino acids.Keywords: high sports performance, combat sports, boxing, Greco-Roman wrestling, athlete nutrition, nutrition profle.

Pre-competition Weight Loss Strategies To Achieve The Desired Category Weight In Combat Sports Collegiate Athletes

PURPOSE: To describe the proportion of college combat athletes that follow some dietary and non-dietary strategies to loss body weight before a competition. METHODS: We evaluated 80 college athletes (21.1 ±2.7 y; 51 males, 29 females) from different combat sports (wrestling 23, boxing 7, judo 21, karate 14, and taekwondo 15; 77.5% of the sample had competitions at national level and 21.3% at international level). We applied a questionnaire to account for some of the followed dietary and non-dietary strategies to achieve the desired competition weight three months before a state tournament. The questionnaire consisted of 35 items. The questions asked the subject if he/she usually perform that strategy for pre-competition weight loss. Also, the questionnaire asked the subjects about if they showed some of the most common side effects of weight loss. The results were reported as frequencies and proportions. RESULTS: The most common dietary strategies for pre-competition weight loss were to reduce or avoid the consumption of fats and flours and sugars (Table 1). On the other hand, the most common non-dietary strategies to pre-competition weight loss were increasing physical activity and using sauna (Table 1). The most common side effect related to pre-competition weight loss was overall fatigue (39, 48.8%), followed by low performance in trainings (30, 37.5%), susceptibility to diseases (29, 36.3%) and irritability or aggressiveness (27, 33.8%). CONCLUSIONS: The reduction of fat consumption and the increase of physical activity were the most common strategies for pre-competition weight loss. Some extreme strategies were also reported but not as common. Some of the mechanisms of these strategies may be related to the side effects of weight loss and not just for the weight loss itself. A comparison by sex and by type of sports deserves further analysis.Table 1: Proportion of dietary and non-dietary strategies for pre-competition weight loss

Особенности питания спортсменов-единоборцев

Особенности питания спортсменов-единоборцев

Effect of rapid weight loss and glutamine supplementation on immunosuppression of combat athletes: a double-blind, placebo-controlled study

The role of plasma glutamine concentration and glutamine supplementation on immunosuppression was investigated in combat athletes. Twenty-three male athletes were randomly assigned to receive glutamine (21 g/day, n=12) or placebo (ovalbumin, n=11) for 10 days. Six athletes who did not lose weight served as controls. Athletes were assessed 21 days before (−21d), 1 day before (−1d) and 5 days after (+5d) a competition. Weight reduction was similar between glutamine (−8.2%± 4.1%) and placebo (−8.5%±2.4%) and negligible in control (−0.6%±1.4%). In both weight-loss groups, the majority of athletes reported symptoms of upper respiratory symptoms, as assessed by the Wisconsin upper respiratory symptom survey questionnaire. Only two athletes reported symptoms in the control group. Immune cell function remained unchanged throughout the study except for an increase in neutrophil phagocytic activity (placebo: −21d=5,251±2,986; −1d=17,428±22,374; +5d=21,125±21,934; glutamine: −21d=6,096±3,549; −1d=11,029±17,113; +5d=28,186±21,032 FI) and a minor change in monocyte phagocytic activity (placebo: −21d=4,421±3,634; −1d=3,329±6,283; +5d=3,243± 2,553; glutamine: −21d=4,051±3,186; −1d=3,106±2,625; +5d=4,981± 4,598) in both glutamine and placebo after weight loss. Plasma glutamine and cortisol remained unchanged across the study. creatine kinase levels were increased in placebo (−21d=125.2±54.1; −1d=187.2± 73.5; +5d=111.3±59.1 U/L) but not in glutamine (−21d=136.2±58.2; −1d= 168.8±65.0; +5d=129.7±64.0 U/L). Rapid weight loss increased the frequency and severity of infection symptoms, but this was neither associated with plasma glutamine depletion nor counteracted by glutamine supplementation.

Sensitivity to pain and strategies of coping with stress in combat athletes

Sensitivity to pain and strategies of coping with stress in combat athletes