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The six-minute walking test (6MWT) is commonly used to measure functional capacity in field settings, primarily through the distance covered. This study aims to establish reference curves for the six-minute walking distance (6MWD) and peak heart rate (PHR) and develop a predictive equation for cardiovascular capacity in Tunisian children and adolescents. A total of 1501 participants (706 boys and 795 girls), aged 10-18 years, were recruited from schools in Tunisia. The Lambda (L), Mu (M), and Sigma (S) methods (LMS method) were employed to develop smoothed percentile curves for 6MWD and PHR. Multivariate linear regression was utilized to formulate a prediction equation for 6MWD. Smoothed percentiles (3rd, 10th, 25th, 50th, 75th, 90th, and 97th) for 6MWD and PHR were presented with age. All variables showed a strong positive correlation (p < 0.001) with a six-minute walking distance (r ranged from 0.227 to 0.558 for girls and from 0.309 to 0.610 for boys), except resting heart rate, which showed a strong negative correlation (girls: r = -0.136; boys: r = -0.201; p < 0.001). Additionally, PHR showed a weak correlation (p > 0.05). The prediction equations, based on age as the primary variable, were established for both genders. For boys: 6MWD = 66.181 + 38.142 × Age (years) (R2 = 0.372; Standard Error of Estimate (SEE) = 122.13), and for girls: 6MWD = 105.535 + 28.390 × Age (years) (R2 = 0.312; SEE = 103.66). The study provides normative values and predictive equations for 6MWD and PHR in Tunisian children and adolescents. These findings offer essential tools for identifying, monitoring, and interpreting cardiovascular functional deficits in clinical and research settings.
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PURPOSE: Physical inactivity is considered an important risk factor for osteoporosis, however, some athletes performing extremely high training volumes can also develop bone mass loss. Moreover, the effect of total body mass or body surface area on bone mineral density remains controversial. Therefore, the aim of this study was to compare the absolute bone mineral density and bone mineral density adjusted to body surface area between amateur triathletes and nonactive women. METHODS: Forty-two healthy women (23 amateur triathletes and 19 nonactive individuals) were evaluated for body composition using a dual-energy X-ray absorptiometry system. RESULTS: Compared to nonactive women, amateur triathletes exhibited lower body mass index (p < 0.001), lower bone mineral density (p < 0.001), and body surface area (p < 0.001). However, bone mineral density adjusted by body surface area in the triathletes was higher than in the nonactive women (p = 0.03). CONCLUSION: These findings showed that amateur triathles presented lower absolute bone mineral density, but higher bone mineral density adjusted to body surface area. Future studies are recommended to identify if the higher bone mineral density adjusted to body surface area are associated with a lower bone fragility.
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Absorciometría de Fotón , Atletas , Densidad Ósea , Humanos , Densidad Ósea/fisiología , Femenino , Estudios Transversales , Adulto , Persona de Mediana Edad , Composición Corporal/fisiología , Índice de Masa Corporal , Natación/fisiología , Osteoporosis/fisiopatología , Osteoporosis/diagnóstico por imagenRESUMEN
Backstroke has been thoroughly investigated in the context of sports science. However, we have no knowledge about the nationalities of the fastest age group backstroke swimmers. Therefore, the present study intended to investigate the nationalities of the fastest backstroke swimmers. For all World Masters Championships held between 1986 and 2024, the year of competition, the first and last name, the age, and the age group, and both the stroke and the distance were recorded for each swimmer. Descriptive data were presented using mean, standard deviation, maximum and minimum values, and confidence intervals. The top ten race times for each swimming distance and sex were identified for descriptive purposes. Nationalities were then grouped into six categories: the top five nationalities with the most appearances in the backstroke swimming top ten times by distance each year and one group consisting of all other nationalities. The Kruskal-Wallis test compared nationality differences, followed by Bonferroni-adjusted pairwise comparisons to identify specific distinctions. Between 1986 and 2024, most age group backstroke swimmers (39.6%) competed in the 50 m event (11,964, 6206 women, and 5,758 men), followed by the 100 m event (32.3%, n = 9764, 5157 women, and 4607 men), and the 200 m event (28.1%, n = 8483, 4511 women, and 3,972 men). Germany had the highest number of top ten female swimmers in the 50 m backstroke distance. Brazil had the highest number of top ten male swimmers in the same distance. The USA had the highest number of female and male swimmers among the top ten in the 100 m and 200 m backstroke distances. Germany and Great Britain were the only countries with swimmers in the top ten for all female backstroke distances. Brazil, the USA, Italy, and Germany were the countries that had swimmers in the top ten for all male backstroke distances. In summary, the fastest backstroke age group swimmers originated from Germany, Brazil, USA, Great Britain, and Italy, where differences between the sexes and race distances exist.
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Natación , Humanos , Masculino , Femenino , Adulto , Rendimiento Atlético/estadística & datos numéricos , Rendimiento Atlético/fisiología , Persona de Mediana Edad , Adulto Joven , Atletas/estadística & datos numéricos , Factores de Edad , Anciano , AdolescenteRESUMEN
BACKGROUND: Diagnoses entered by general practitioners into electronic medical records have great potential for research and practice, but unfortunately, diagnoses are often in uncoded format, making them of little use. Natural language processing (NLP) could assist in coding free-text diagnoses, but NLP models require local training data to unlock their potential. The aim of this study was to develop a framework of research-relevant diagnostic codes, to test the framework using free-text diagnoses from a Swiss primary care database and to generate training data for NLP modelling. METHODS: The framework of diagnostic codes was developed based on input from local stakeholders and consideration of epidemiological data. After pre-testing, the framework contained 105 diagnostic codes, which were then applied by two raters who independently coded randomly drawn lines of free text (LoFT) from diagnosis lists extracted from the electronic medical records of 3000 patients of 27 general practitioners. Coding frequency and mean occurrence rates (n and %) and inter-rater reliability (IRR) of coding were calculated using Cohen's kappa (Κ). RESULTS: The sample consisted of 26,980 LoFT and in 56.3% no code could be assigned because it was not a specific diagnosis. The most common diagnostic codes were, 'dorsopathies' (3.9%, a code covering all types of back problems, including non-specific lower back pain, scoliosis, and others) and 'other diseases of the circulatory system' (3.1%). Raters were in almost perfect agreement (Κ ≥ 0.81) for 69 of the 105 diagnostic codes, and 28 codes showed a substantial agreement (K between 0.61 and 0.80). Both high coding frequency and almost perfect agreement were found in 37 codes, including codes that are particularly difficult to identify from components of the electronic medical record, such as musculoskeletal conditions, cancer or tobacco use. CONCLUSION: The coding framework was characterised by a subset of very frequent and highly reliable diagnostic codes, which will be the most valuable targets for training NLP models for automated disease classification based on free-text diagnoses from Swiss general practice.
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Codificación Clínica , Registros Electrónicos de Salud , Médicos Generales , Procesamiento de Lenguaje Natural , Registros Electrónicos de Salud/estadística & datos numéricos , Humanos , Reproducibilidad de los Resultados , Codificación Clínica/métodos , Médicos Generales/educación , Suiza/epidemiología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Clasificación Internacional de EnfermedadesRESUMEN
BACKGROUND: Monitoring the career intentions of medical students during their undergraduate studies could help to address the shortage of physicians, particularly in general practice. This study aimed to investigate changes in medical students' career openness, attractiveness and determinants of medical career choice during their bachelor's studies. METHODS: The design was cross-sectional, recruiting all medical students who started a bachelor's program in one of the four different educational tracks in Zurich, Switzerland, in the fall of 2019 (first survey) and completed it in the summer of 2022 (second survey). Students' perceptions of the attractiveness and determinants of different medical career options were assessed using a structured online questionnaire. Absolute changes between the two-time points were reported in percentage points overall and by educational track. Regression analysis was used to examine the association of student characteristics and determinants of career options with the attractiveness of each option. RESULTS: We surveyed 354 medical students at the beginning and 433 at the end of the bachelor's program (participation rate: 71.1% and 86.9%, respectively). Overall, the proportion of students open to all proposed medical career options decreased (from 52.8% to 43.8%, p = 0.004). The attractiveness of outpatient gynecology or pediatrics increased (from 27.4% to 43.4%, p < 0.001), whereas the attractiveness of both general and specialized inpatient care decreased (from 47.8% to 40.3%, p = 0.05 and from 71.1% to 61.1%, p = 0.006 respectively). There was an increase in the proportion of students who perceived part-time work, autonomy and relationships with patients as important career determinants (from 47.3% to 64.7%, p < 0.001; from 63.3% to 77.8%, p < 0.001; from 80.8% to 89.3%, p = 0.002 respectively), while the importance of reputation and career opportunities decreased (from 42.6% to 26.2%, p < 0.001; from 79.2% to 63.6%, p < 0.001 respectively). The importance of part-time work and relationships with patients were positively associated with the attractiveness of general practice. CONCLUSIONS: During the bachelor's program, the attractiveness of a career in general practice tended to decrease, but the importance of part-time work, autonomy and relationships with patients as career determinants increased. Helping students understand how these determinants relate to general practice may increase their interest in the profession. TRIAL REGISTRATION: Not applicable.
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Selección de Profesión , Estudiantes de Medicina , Humanos , Suiza , Estudios Transversales , Femenino , Estudiantes de Medicina/psicología , Masculino , Adulto Joven , Educación de Pregrado en Medicina , Facultades de Medicina , Adulto , Encuestas y CuestionariosRESUMEN
The present study aimed to compare VÌO2max (absolute, adjusted to total body mass, and adjusted to lean mass) in recreational runners and sedentary women < and > 50 yr and verify the effect of aging and physical activity level on the three types of VÌO2 max expression. The study included 147 women:85 runners (45.7 ± 14.1 yr) and 62 sedentary controls (48.8 ± 9.8 yr). They were subjected to cardiopulmonary exercise testing for VÌO2 max measurement and a body composition test by dual-emission X-ray absorptiometry system. VÌO2max were expressed as absolute values (L/min), relative to total body mass values (mL/kg/min), and relative to lean mass values (mL/kgLM/min). The two-way analysis of variance revealed a significant interaction [F(2,131) = 4.43, p < 0.001] and effects of age group [F(2,131) = 32.79, p < 0.001] and physical activity group [F(2,131) = 55.64, p < 0.001] on VÌO2max (mL/min). VÌO2max (mL/kg/min) and VÌO2 max (mL/kgLM/min) were significantly influenced by age and physical activity levels. The multiple regression model explains 76.2 % of the dependent variable VÌO2max (mL/kg/min), age (ß = -0.335, t = -7.841, p < 0.001), and physical activity group (ß = -0.784, t = -18.351, p < 0.001). In conclusion, female runners had higher VÌO2 max values than sedentary women at all ages, even though aging has a greater impact on VÌO2 max in the runners group. In addition to cardiorespiratory fitness, women's metabolic lean mass function, as measured by VÌO2max adjusted by lean mass, is significantly influenced by aging. Finally, physical activity has a greater impact on VÌO2 max levels than aging.
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Envejecimiento , Composición Corporal , Prueba de Esfuerzo , Consumo de Oxígeno , Carrera , Conducta Sedentaria , Humanos , Femenino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Carrera/fisiología , Adulto , Envejecimiento/fisiología , Composición Corporal/fisiología , Absorciometría de Fotón , Anciano , Estudios de Casos y Controles , Ejercicio Físico/fisiologíaRESUMEN
Self-modeling (SM) and self-control (SC) feedback can be presented as two solutions for learning improvement. Therefore, the aim of the present study was to investigate the effects of SM and SC feedback on 100-m freestyle performance of professional swimmers and waterpolo players. 25 elite male swimmers and waterpolo players, were randomly assigned to four groups: swimmer group with SM, swimmer group with SM and SC feedback, waterpolo players group with SM, and waterpolo players group with SM and SC feedback. 100-m freestyle times and performance were recorded. SM and SC feedback for the participants were utilized at the acquisition stage. The device used included a Lenovo B570 laptop and an Exilim ZR200 canon camcorder. SM and SC feedback presented to the swimmers and waterpolo players led to improved speed and results, and the effect of presenting SM with SC feedback to swimmers had better results. In conclusion, the present study indicates that SC modeling of watching video is a suitable method for professional swimmers. Water polo trainers can also use SM and SC feedback to enhance their players' swimming technique.
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Participation in marathons has dramatically increased over the last few years. Marathon running has many proven beneficial effects, especially on cardiovascular health and fitness. Most research has focused on physiologic and pathophysiologic adaptations in connection with endurance exercise. Nevertheless, marathon running also has a major impact on psychological aspects and positively influences mental health, which has only recently attracted research interest. The present narrative review aimed to review the personality traits of marathon runners with an emphasis on recent literature. Marathon runners show a distinct personality and highly characteristic personality traits needed to successfully finish such a demanding race, i.e., a strong sense of vigor, self-sufficiency, and intelligence as well as low scores in anger, fatigue, tension, and depression. Furthermore, personality differences are detectable between runners of different sexes, ages, and performance level groups. This has significant clinical implications for athletes, coaches and competition organizers, as these groups show different patterns of personality traits. Future studies should focus on changes in cognition and mood states pre-, during, and post-endurance events, as well as during training periods. Large-scale studies comparing personality differences by sex, age, and performance are also important for better clinical guidance. See also the graphical abstract(Fig. 1).
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BACKGROUND: Ultra-endurance events are gaining popularity in multiple exercise disciplines, including cycling. With increasing numbers of ultra-cycling events, aspects influencing participation and performance are of interest to the cycling community. MAIN BODY: The aim of this narrative review was, therefore, to assess the types of races offered, the characteristics of the cyclists, the fluid and energy balance during the race, the body mass changes after the race, and the parameters that may enhance performance based on existing literature. A literature search was conducted in PubMed, Scopus, and Google Scholar using the search terms 'ultracycling', 'ultra cycling', 'ultra-cycling', 'ultra-endurance biking', 'ultra-bikers' and 'prolonged cycling'. The search yielded 948 results, of which 111 were relevant for this review. The studies were classified according to their research focus and the results were summarized. The results demonstrated changes in physiological parameters, immunological and oxidative processes, as well as in fluid and energy balance. While the individual race with the most published studies was the Race Across America, most races were conducted in Europe, and a trend for an increase in European participants in international races was observed. Performance seems to be affected by characteristics such as age and sex but not by anthropometric parameters such as skin fold thickness. The optimum age for the top performance was around 40 years. Most participants in ultra-cycling events were male, but the number of female athletes has been increasing over the past years. Female athletes are understudied due to their later entry and less prominent participation in ultra-cycling races. A post-race energy deficit after ultra-cycling events was observed. CONCLUSION: Future studies need to investigate the causes for the observed optimum race age around 40 years of age as well as the optimum nutritional supply to close the observed energy gap under consideration of the individual race lengths and conditions. Another research gap to be filled by future studies is the development of strategies to tackle inflammatory processes during the race that may persist in the post-race period.
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Previous studies have shown that variations in the CD36 gene may affect phenotypes associated with fat metabolism as the CD36 protein facilitates the transport of fatty acids to the mitochondria for oxidation. However, no previous study has tested whether variations in the CD36 gene are associated with sports performance. We investigated the genotypic and allelic distribution of the single-nucleotide polymorphism (SNP) rs1761667 in the CD36 gene in elite Moroccan athletes (cyclists and hockey players) in comparison with healthy non-athletes of the same ethnic origin. Forty-three Moroccan elite male athletes (nineteen cyclists and twenty-four field hockey players) belonging to the national teams of their respective sports (athlete group) were compared to twenty-eight healthy, active, male university students (control group). Genotyping of the CD36 rs1761667 (G>A) SNP was performed via polymerase chain reaction (PCR) and Sanger sequencing. A chi-square (χ2) test was used to assess the Hardy-Weinberg equilibrium (HWE) and to compare allele and genotype frequencies in the "athlete" and "control" groups. The genotypic distribution of the CD36 rs1761667 polymorphism was similar in elite athletes (AA: 23.81, AG: 59.52, and GG: 16.67%) and controls (AA: 19.23, AG: 69.23, and GG: 11.54%; χ2 = 0.67, p = 0.71). However, the genotypic distribution of the CD36 rs1761667 polymorphism was different between cyclists (AA: 0.00, AG: 72.22, and GG: 27.78%) and hockey players (AA: 41.67, AG: 50.00, and GG: 8.33%; χ2 = 10.69, p = 0.004). Specifically, the frequency of the AA genotype was significantly lower in cyclists than in hockey players (p = 0.02). In terms of allele frequency, a significant difference was found between cyclists versus field hockey players (χ2 = 7.72, p = 0.005). Additionally, there was a predominance of the recessive model in cyclists over field hockey players (OR: 0.00, 95% CI: 0.00-0.35, p = 0.002). Our study shows a significant difference between cyclists and field hockey players in terms of the genotypic and allelic frequency of the SNP rs1761667 of the CD36 gene. This divergence suggests a probable association between genetic variations in the CD36 gene and the type of sport in elite Moroccan athletes.
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Atletas , Antígenos CD36 , Polimorfismo de Nucleótido Simple , Humanos , Antígenos CD36/genética , Masculino , Marruecos , Adulto , Genotipo , Proyectos Piloto , Frecuencia de los Genes , Adulto Joven , Alelos , Ciclismo , Hockey , Rendimiento AtléticoRESUMEN
The 50-km ultra-marathon is a popular race distance, slightly longer than the classic marathon distance. However, little is known about the country of affiliation and age of the fastest 50-km ultra-marathon runners and where the fastest races are typically held. Therefore, this study aimed to investigate a large dataset of race records for the 50-km distance race to identify the country of affiliation and the age of the fastest runners as well as the locations of the fastest races. A total of 1,398,845 50-km race records (men, n = 1,026,546; women, n = 372,299) were analyzed using both descriptive statistics and advanced regression techniques. This study revealed significant trends in the performance of 50-km ultra-marathoners. The fastest 50-km runners came from African countries, while the fastest races were found to occur in Europe and the Middle East. Runners from Ethiopia, Lesotho, Malawi, and Kenya were the fastest in this race distance. The fastest 50-km racecourses, providing ideal conditions for faster race times, are in Europe (Luxembourg, Belarus, and Lithuania) and the Middle East (Qatar and Jordan). Surprisingly, the fastest ultra-marathoners in the 50-km distance were found to fall into the age group of 20-24 years, challenging the conventional belief that peak ultra-marathon performance comes in older age groups. These findings contribute to a better understanding of the performance models in 50-km ultra-marathons and can serve as valuable insights for runners, coaches, and race organizers in optimizing training strategies and racecourse selection.
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Rendimiento Atlético , Carrera de Maratón , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Pueblo de África Oriental , Kenia , Resistencia Física , Distribución por EdadRESUMEN
This study investigated the combined effects of 12 weeks of high-intensity interval training (HIIT) and spirulina supplementation on adipokine levels, insulin resistance, anthropometric indices, and cardiorespiratory fitness in 44 obese males (aged 25-40 years). The participants were randomly assigned to one of four groups: control (CG), supplement (SG), training (TG), or training plus supplement (TSG). The intervention involved daily administration of either spirulina or a placebo and HIIT three times a week for the training groups. Anthropometric indices, HOMA-IR, VO2peak, and circulating adipokines (asprosin and lipocalin2, omentin-1, irisin, and spexin) were measured before and after the 12-week intervention. Post-intervention analysis indicated differences between the CG and the three interventional groups for body weight, fat-free mass (FFM), percent body fat (%BF), HOMA-IR, and adipokine levels (p < 0.05). TG and SG participants had increased VO2peak (p < 0.05). Spirulina supplementation with HIIT increased VO2peak, omentin-1, irisin, and spexin, while causing decreases in lipocalin-2 and asprosin levels and improvements in body composition (weight, %fat), BMI, and HOMA-IR. Notably, the combination of spirulina and HIIT produced more significant changes in circulating adipokines and cardiometabolic health in obese males compared to either supplementation or HIIT alone (p < 0.05). These findings highlight the synergistic benefits of combining spirulina supplementation with HIIT, showcasing their potential in improving various health parameters and addressing obesity-related concerns in a comprehensive manner.
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Purpose: Endurance sports performance is influenced by several factors, including maximal oxygen uptake (â©O2max), the percentage of â©O2max that can be sustained in endurance events, running economy, and body composition. Traditionally, â©O2max can be measured as an absolute value, adjusted for body mass, reflecting the athlete's central capacity (maximal cardiac output), or adjusted for lean mass (LM), reflecting the athlete's peripheral capacity (muscular oxidative capacity). The present study aims to evaluate absolute, total body mass, and lower limb LM-adjusted â©O2max, ventilatory thresholds (VT), respiratory compensation points (RCP), and body composition during two training periods separated by 8 months. Patients and Methods: Thirteen competitive amateur triathletes [seven men (40.7±13.7 years old, 76.3±8.3kg, and 173.9±4.8cm) and six women (43.5±6.9 years old, 55.0±2.7kg, 164.9±5.2cm)] were evaluated for body composition with dual-energy X-ray absorptiometry and â©O2max, VT, RPC, and maximal aerobic speed (MAS) with a cardiorespiratory maximal treadmill test. Results: The absolute â©O2max (p = 0.003, d = 1.05), body mass-adjusted â©O2max (p < 0.001, d = 1.2859), and MAS (p = 0.047, d = 0.6139) values differed significantly across evaluation periods. Lower limb LM-adjusted â©O2max (p = 0.083, d = -0.0418), %â©O2max at VT (p = 0.541, d = -0.1746), speed at VT (p = 0.337, d = -0.2774), % â©O2max at RCP (p = 0.776, d = 0.0806), and speed at RCP (p = 0.436, d = 0.2234) showed no difference. Conclusion: The sensitivities of â©O2max adjusted for body mass and â©O2max adjusted for LM to detect changes in physical training state differ. Furthermore, decreases in physical fitness level, as evaluated by â©O2max values, are not accompanied by changes in VT.
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Little is known about the prevalent nationalities among the best-placed athletes participating in "Ironman Hawaii." Moreover, the age at which athletes achieve their best performances remains unclear. The present study aimed to compare the prevalent nationalities among the athletes, their respective placement among the top five, and the performance difference between the different age groups in 'Ironman Hawaii' from 2003 to 2019. A total of 30 354 amateur triathletes were selected from the Obsessed Triathlete (OBSTRI) website. A "TOP 5" division filter was applied for further analysis, resulting in 1 851 athletes being included in this study. Among the male runners, Americans participated the most in Ironman events (39%), followed by Germans (10%). Among female runners, Americans participated the most (54%), followed by Australian runners (8%). Male Americans also featured most among the top five (30%), followed by Germans (16%). Female Americans were the most prevalent among the top five (47%), followed by Australian Americans (10%). There were no significant performance differences (p â> â0.05) between the 25-29 and 40-44 age groups for either sex. The 45-49 age group presented significantly worse performance than the 35-39 age group for both sexes (p â< â0.001). North Americans were the most performant and frequent participants in "Ironman Hawaii." The expected performance decline due to aging was observed after 45 years in both sexes.
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This study evaluated the acute effect of the exergame Kinect Sports® beach volleyball on state anxiety level in adult women. Thirty healthy adult women (age: 21 [4] years, body mass: 54.70 [19.50] kg, height: 1.61 ± 0.05 m, and body mass index: 21.87 [5.76] kg/m2, data are expressed as median [interquartile range] and as the mean ± standard deviation) were assigned to play an exergame of beach volleyball in singleplayer mode session (intervention session) for ~ 30 min using the Xbox 360 Kinect® or remained seated (control session). State anxiety was evaluated before and after the intervention and control sessions through the State-Trait Anxiety Inventory. State anxiety obtained in both sessions (exergame and control) was classified as intermediate before (median: 36.00 [IQR: 4.75] and mean = 38.73 ± 7.23, respectively) and after (mean: 34.86 ± 6.81 and mean: 37.66 ± 8.44, respectively). Friedman test found no time significant effect on state anxiety of the sessions (χ2 [3] = 6.45, p-value = 0.092, Kendall's W = 0.07 "trivial"). In conclusion, the present study showed that there were no significant differences in the state anxiety level after an acute session of the exergame beach volleyball.
KEY POINTS: ⢠Exergame beach volleyball presented high enjoyment and a moderate to strong future engagement possibility. ⢠A session of the volleyball exergame did not improve affectivity and state anxiety level compared with control condition. ⢠A session of the volleyball exergame elicited moderate physical exercise intensity.
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Background and Objectives: Pacing analyses for increasingly popular long-distance running disciplines have been in researchers' spotlight for several years. In particular, assessing pacing variability in long-distance running was hardly achievable since runners must repeat long-running trials for several days. Potential solutions for these problems could be multi-stage long-distance running disciplines. Therefore, this study aimed to assess the long-distance running variability as well as the reliability, validity, and sensitivity of the variables often used for pacing analyses. Materials and Methods: This study collected the split times and finish times for 20 participants (17 men and three women; mean age 55.5 years ± 9.5 years) who completed the multiday marathon running race (five marathons in 5 days), held as part of the Bretzel Ultra Tri in Colmar, France, in 2021. Seven commonly used pacing variables were subsequently calculated: Coefficient of variation (CV), Change in mean speed (CS), Change in first lap speed (CSF), Absolute change in mean speed (ACS), Pace range (PR), Mid-race split (MRS), and First 32 km-10 km split (32-10). Results: Multi-stage marathon running showed low variability between days (Intraclass correlation coefficient (ICC) > 0.920), while only the CV, ACS, and PR variables proved to have moderate to good reliability (0.732 < ICC < 0.785). The same variables were also valid (r > 0.908), and sensitive enough to discern between runners of different performance levels (p < 0.05). Conclusions: Researchers and practitioners who aim to explore pacing in long-distance running should routinely utilize ACS, CV, and PR variables in their analyses. Other examined variables, CS, CSF, MRS, and 32-10, should be used cautiously. Future studies might try to confirm these results using different multi-stage event's data as well as by expanding sensitivity analysis to age and gender differences.
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Rendimiento Atlético , Carrera , Masculino , Humanos , Femenino , Persona de Mediana Edad , Resistencia Física , Carrera de Maratón , Reproducibilidad de los Resultados , Factores de TiempoRESUMEN
Introduction: Our study examined 16,611 records of professional triathletes from 163 Ironman® 70.3 races across 97 countries (2004-2020). The aim was to identify the most predictive discipline-swim, bike, or run-for overall race time. Methods: We used correlation matrices to compare the dependent variable "finish time" with independent variables "swim time," "bike time," and "run time." This analysis was conducted separately for male and female athletes. Additionally, univariate and multiple linear regression models assessed the strength of these associations. Results: The results indicated that "bike time" had the strongest correlation with finish time (0.85), followed by "run time" (0.75 for females, 0.82 for males) and "swim time" (0.46 for females, 0.63 for males). Regression models confirmed "bike time" as the strongest predictor of overall race time (R² = 0.8), with "run time" and "swim time" being less predictive. Discussion: The study concludes that in Ironman 70.3 races, "bike time" is the most significant predictor of overall race performance for both sexes, suggesting a focus on cycling in training and competition strategies. It also highlights a smaller performance gap between genders in swimming than in cycling or running.
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Endotoxins are pyrogenic lipopolysaccharides from Gram-negative bacteria that are known to induce fever, septic shock, and multiple organ failure, posing a substantial risk to human health. Drinking water systems are especially prone to home microbiomes containing a large variety of Gram-negative bacteria. Consumption of water from these systems in developed countries is generally regarded as non-hazardous to humans due to the low number of non-pathogenic bacterial cells per milliliter and oral admission. To assess potential risks posed by endotoxins in drinking water systems, we conducted a conventional microbiological investigation on a local community water system in the north of Germany and mined the resulting data to investigate the endotoxin contents of some of the most abundant microbiota found during these analyses. Using a Limulus amoebocyte lysate (LAL) -based endotoxin detection method, average normalized endotoxin content was determined. Although the average culturable amounts of microbiota in the drinking water system were insufficient to exert endotoxin levels critical to human health, peaks and acute contaminations may pose substantial health risks.
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Agua Potable , Microbiota , Humanos , Endotoxinas , Fiebre , AlemaniaRESUMEN
This study aimed to investigate the effects of swimming in cold water on the release of FGF21 from various tissues and its impact on fat metabolism. Twenty Wistar rats were randomly divided into three groups: untrained (C), trained in thermo-neutral water (TN, 30 °C) and trained in cold water (TC, 15 °C). The training groups swam intervals (2-3 min) until exhaustion, 1 min rest, three days a week for six weeks, with 3-6% bodyweight load. The mRNA expression of variables was determined in white fat tissue (WAT), and FGF21 protein was also measured in the liver, brown fat tissue (BAT), serum, and muscle. The experimental protocols resulted in lower body weight gain, associated with reduced WAT volume; the most remarkable improvement was observed in the TC group. Swimming significantly increased FGF21 protein levels in WAT, BAT, and muscle tissues compared to the C group; substantial increases were in the TC group. Changes in FGF21 were highly correlated with the activation of genes involved in fat metabolisms, such as CPT1, CD36, and HSL, and with glycerol in WAT. The findings indicate a positive correlation between swimming in cold water and the activation of genes involved in fat metabolism, possibly through FGF21 production, which was highly correlated with fat-burning genes.