Refined Analysis of a Cross-Sectional Doping Survey Among Recreational Triathletes: Support for the Nutritional Supplement Gateway Hypothesis
Ontology highlight
ABSTRACT:
SUBMITTER: Heller S
PROVIDER: S-EPMC7538671 | biostudies-literature | 2020 Jan
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:PURPOSE:This study assessed the prevalence of physical and cognitive doping in recreational triathletes with two different randomized response models, that is, the Cheater Detection Model (CDM) and the Unrelated Question Model (UQM). Since both models have been employed in assessing doping, the major objective of this study was to investigate whether the estimates of these two models converge. MATERIAL AND METHODS:An anonymous questionnaire was distributed to 2,967 athletes at two triathlon events (Frankfurt and Wiesbaden, Germany). Doping behavior was assessed either with the CDM (Frankfurt sample, one Wiesbaden subsample) or the UQM (one Wiesbaden subsample). A generalized likelihood-ratio test was employed to check whether the prevalence estimates differed significantly between models. In addition, we compared the prevalence rates of the present survey with those of a previous study on a comparable sample. RESULTS:After exclusion of incomplete questionnaires and outliers, the data of 2,017 athletes entered the final data analysis. Twelve-month prevalence for physical doping ranged from 4% (Wiesbaden, CDM and UQM) to 12% (Frankfurt CDM), and for cognitive doping from 1% (Wiesbaden, CDM) to 9% (Frankfurt CDM). The generalized likelihood-ratio test indicated no differences in prevalence rates between the two methods. Furthermore, there were no significant differences in prevalences between the present (undertaken in 2014) and the previous survey (undertaken in 2011), although the estimates tended to be smaller in the present survey. DISCUSSION:The results suggest that the two models can provide converging prevalence estimates. The high rate of cheaters estimated by the CDM, however, suggests that the present results must be seen as a lower bound and that the true prevalence of doping might be considerably higher.
| S-EPMC4878800 | biostudies-literature
Project description:This study investigated the use of performance-enhancing substances in recreational triathletes who were competing in German races at distances ranging from super-sprint to long-distance, as per the International Triathlon Union. The use of legal drugs and over-the-counter supplements over the previous year, painkillers over the previous 3 months, and the potential three-month prevalence of physical doping and or cognitive doping in this group were assessed via an anonymous questionnaire. The Randomised Response Technique (RRT) was implemented for sensitive questions regarding "prescription drugs […] for the purpose of performance enhancement […] only available at a pharmacy or on the black market". The survey did not directly state the word "doping," but included examples of substances that could later be classed as physical and or cognitive doping. The subjects were not required to detail what they were taking. Overall, 1953 completed questionnaires were received from 3134 registered starters at six regional events-themselves involving 17 separate races-in 2017. Of the respondents, 31.8% and 11.3% admitted to the use of dietary supplements, and of painkillers during the previous three months, respectively. Potential physical doping and cognitive doping over the preceding year were reported by 7.0% (Confidence Interval CI: 4.2-9.8) and 9.4% (CI: 6.6-12.3) of triathletes. Gender, age, experience in endurance sports, and number of weekly triathlon training hours were linked to potential physical or cognitive doping. Given the potentially relevant side effects of painkiller use and physical and or cognitive doping, we recommend that educational and preventative measures for them be implemented within amateur triathlons.
| S-EPMC6956052 | biostudies-literature
Project description:Little is known about how recreational triathletes prepare for an Olympic distance event. The aim of this study was to identify the training characteristics of recreational-level triathletes within the competition period and assess how their preparation for a triathlon influences their health and their levels of fatigue. During the 6 weeks prior to, and the 2 weeks after, an Olympic distance triathlon, nine recreational athletes (five males, four females) completed a daily training log. Participants answered the Daily Analysis of Life Demands Questionnaire (DALDA), the Training Distress Scale (TDS) and the Alberta Swim Fatigue and Health Questionnaire weekly. The Recovery-Stress Questionnaire (REST-Q) was completed at the beginning of the study, on the day before the competition, and at the end of week 8. Training loads were calculated using session-based rating of perceived exertion (sRPE). The data from every week of training was compared to week 1 to determine how athletes' training and health changed throughout the study. No changes in training loads, duration or training intensity distribution were seen in the weeks leading up to the competition. Training duration was significantly reduced in week 6 (p = 0.041, d = 1.58, 95% CI = 6.9, 421.9), while the number of sessions was reduced in week 6 (Z = 2.32, p = 0.02, ES = 0.88) and week 7 (Z = 2.31, p = 0.02, ES = 0.87). Training was characterized by large weekly variations in training loads and a high training intensity. No significant changes were seen in the DALDA, TDS or REST-Q questionnaire scores throughout the 8 weeks. Despite large spikes in training load and a high overall training intensity, these recreational-level triathletes were able to maintain their health in the 6 weeks of training prior to an Olympic distance triathlon.
| S-EPMC8309729 | biostudies-literature
Project description:This study investigated whether dietary supplement acceptance mediated the relationship between supplement use and doping attitudes in youth sports. To this end, we employed a two-wave half-longitudinal design during a sports season (time point one [T1] to time point two [T2]). The sample consisted of 217 elite youth athletes (47% male; mean age = 16.98 years, standard deviation = 0.88) who competed in team sports (43%; N = 93; basketball, floorball, handball, and ice hockey) and individual sports (57%; N = 124; alpine skiing, biathlon, cross-country skiing, swimming, and tennis). The participants were recruited from eight Norwegian sports academy high schools that provide extracurricular, higher-level training and specialization for youth athletes. Results from structural equation modeling analysis indicated that dietary supplement acceptance (T2) mediated the positive relationship between supplement use (T1) and doping attitudes (T2) when accounting for prior levels of the mediator and the outcome variable. These findings suggest that when young athletes used dietary supplements at the start of the season to improve their performance, they were more likely to view the use of supplements as acceptable and to report more favorable attitudes toward doping at the end of the season six months later. For those seeking to prevent doping in youth sports, targeting athletes' views on the acceptable use of dietary supplements may be important.
| S-EPMC10833512 | biostudies-literature
Project description:BACKGROUND: Explanations for the evolution of female-biased, extreme Sexual Size Dimorphism (SSD), which has puzzled researchers since Darwin, are still controversial. Here we propose an extension of the Gravity Hypothesis (i.e., the GH, which postulates a climbing advantage for small males) that in conjunction with the fecundity hypothesis appears to have the most general power to explain the evolution of SSD in spiders so far. In this "Bridging GH" we propose that bridging locomotion (i.e., walking upside-down under own-made silk bridges) may be behind the evolution of extreme SSD. A biomechanical model shows that there is a physical constraint for large spiders to bridge. This should lead to a trade-off between other traits and dispersal in which bridging would favor smaller sizes and other selective forces (e.g. fecundity selection in females) would favor larger sizes. If bridging allows faster dispersal, small males would have a selective advantage by enjoying more mating opportunities. We predicted that both large males and females would show a lower propensity to bridge, and that SSD would be negatively correlated with sexual dimorphism in bridging propensity. To test these hypotheses we experimentally induced bridging in males and females of 13 species of spiders belonging to the two clades in which bridging locomotion has evolved independently and in which most of the cases of extreme SSD in spiders are found. RESULTS: We found that 1) as the degree of SSD increased and females became larger, females tended to bridge less relative to males, and that 2) smaller males and females show a higher propensity to bridge. CONCLUSIONS: Physical constraints make bridging inefficient for large spiders. Thus, in species where bridging is a very common mode of locomotion, small males, by being more efficient at bridging, will be competitively superior and enjoy more mating opportunities. This "Bridging GH" helps to solve the controversial question of what keeps males small and also contributes to explain the wide range of SSD in spiders, as those spider species in which extreme SSD has not evolved but still live in tall vegetation, do not use bridging locomotion to disperse.
| S-EPMC2924870 | biostudies-other
Project description:BackgroundMalnutrition and muscle wasting are common in ICU patients and predict adverse patient-centered outcomes. The Italian Society of Anesthesia Analgesia Resuscitation and Intensive Care (SIAARTI) conducted a nationwide survey to identify the nutritional practices in the Italian ICUs and to plan future, training interventions to improve the national clinical practice.MethodsNationwide online survey, involving Italian ICUs, developed by experts affiliated with SIAARTI. Invitations to participate were distributed through emails and social networks. Data were collected over a period of three months (October 1 to December 31, 2022) during 2022.ResultsOne hundred full responses from participating ICUs were collected. The number of beds is < 10 in most ICUs and > 20 in 11 ICUs. Most ICUs (87%) are mixed, cardiac (5%), neurosurgical (4%), or pediatric ICUs (1%). Although the nutritional program is widely prescribed based on the patients' general evaluation, 52 ICUs (52%) do not perform nutritional risk evaluation at admission in case of > 24-h stay. Daily caloric intake is mainly based on the 25 kcal/kg equation; otherwise, the Harris-Benedict formula is mostly used, whereas indirect calorimetry is less used. Most clinicians apply a personalized nutritional approach to organ failure. Most ICUs have a nutritional management protocol, and enteral nutrition (EN) is frequently started within 2 days from admission, while supplemental parenteral nutrition is used when EN is insufficient by most clinicians. The EN administered seems to correspond to that prescribed, but it is stopped if the gastric residual gastric is > 300-500 ml in most ICUs.ConclusionPrescription, route, and mode of administration of nutritional support seem to be in line with international recommendations, while suggestions on the tools for assessing the nutritional risk and monitoring efficacy and complications seem far less followed. Future national clinical studies are necessary to investigate the optimal nutritional and metabolic management of critically ill patients and the correspondence with the results of this survey on actual practices.
| S-EPMC10631207 | biostudies-literature
Project description:A narrative review with an overall aim of indicating the current state of knowledge and the relevance concerning food and supplement contamination and/or adulteration with doping agents and the respective implications for sports drug testing is presented. The identification of a doping agent (or its metabolite) in sports drug testing samples constitutes a violation of the anti-doping rules defined by the World Anti-Doping Agency. Reasons for such Adverse Analytical Findings (AAFs) include the intentional misuse of performance-enhancing/banned drugs; however, also the scenario of inadvertent administrations of doping agents was proven in the past, caused by, amongst others, the ingestion of contaminated dietary supplements, drugs, or food. Even though controversial positions concerning the effectiveness of dietary supplements in healthy subjects exist, they are frequently used by athletes, anticipating positive effects on health, recovery, and performance. However, most supplement users are unaware of the fact that the administration of such products can be associated with unforeseeable health risks and AAFs in sports. In particular anabolic androgenic steroids (AAS) and stimulants have been frequently found as undeclared ingredients of dietary supplements, either as a result of cross-contaminations due to substandard manufacturing practices and missing quality controls or an intentional admixture to increase the effectiveness of the preparations. Cross-contaminations were also found to affect therapeutic drug preparations. While the sensitivity of assays employed to test pharmaceuticals for impurities is in accordance with good manufacturing practice guidelines allowing to exclude any physiological effects, minute trace amounts of contaminating compounds can still result in positive doping tests. In addition, food was found to be a potential source of unintentional doping, the most prominent example being meat tainted with the anabolic agent clenbuterol. The athletes' compliance with anti-doping rules is frequently tested by routine doping controls. Different measures including offers of topical information and education of the athletes as well as the maintenance of databases summarizing low- or high-risk supplements are important cornerstones in preventing unintentional anti-doping rule violations. Further, the collection of additional analytical data has been shown to allow for supporting result management processes.
| S-EPMC7466328 | biostudies-literature
Project description:Flux balance analysis and constraint based modeling have been successfully used in the past to elucidate the metabolism of single cellular organisms. However, limited work has been done with multicellular organisms and even less with humans. The focus of this paper is to present a novel use of this technique by investigating human nutrition, a challenging field of study. Specifically, we present a steady state constraint based model of skeletal muscle tissue to investigate amino acid supplementation's effect on protein synthesis. We implement several in silico supplementation strategies to study whether amino acid supplementation might be beneficial for increasing muscle contractile protein synthesis. Concurrent with published data on amino acid supplementation's effect on protein synthesis in a post resistance exercise state, our results suggest that increasing bioavailability of methionine, arginine, and the branched-chain amino acids can increase the flux of contractile protein synthesis. The study also suggests that a common commercial supplement, glutamine, is not an effective supplement in the context of increasing protein synthesis and thus, muscle mass. Similar to any study in a model organism, the computational modeling of this research has some limitations. Thus, this paper introduces the prospect of using systems biology as a framework to formally investigate how supplementation and nutrition can affect human metabolism and physiology.
| S-EPMC3740736 | biostudies-literature
Project description:Callitrichidae is a unique primate family not only in terms of the large number of food transfers to infants but also for the prevalence of transfers that are initiated by the adults. It has been hypothesized that, as well as provisioning infants, callitrichid food transfers might function to teach the receiver what food types to eat. If food provisioning has a teaching function, we would expect successful food transfers to be more likely with food types that are novel to the juveniles. We would also expect juveniles to learn about foods from those transfers. We introduced different types of food (some familiar, some novel) to wild groups of golden lion tamarins (Leontopithecus rosalia). While novel foods were not more successfully transferred than familiar food in the experiment, transfers were more successful (i.e., the receiver obtained food) when the donor had previous experience with that food. Moreover, we found evidence suggesting that food transfers influenced the future foraging choices of juveniles. Our findings are consistent with the first and third criteria of the functional definition of teaching, which requires that tutors (the adults) modify their behavior in the presence of a naïve individual (a juvenile), and that the naïve individual learns from the modified behavior of the demonstrator. Our findings are also consistent with the provisioning function of food transfer. Social learning seems to play an important role in the development of young tamarins' foraging preferences.
| S-EPMC7813722 | biostudies-literature
Project description:The gateway hypothesis posits that initial exposure to legal drugs promotes subsequent addiction to illicit drugs. However, epidemiological studies are correlational and cannot rule out the alternative hypothesis of shared addiction vulnerability to legal and illegal drugs. We tested the gateway hypothesis using established rat alcohol exposure procedures and cocaine self-administration and reinstatement (relapse) procedures. We gave Wistar or alcohol-preferring (P) rats intermittent access to water or 20% alcohol in their homecage for 7 weeks (three 24-h sessions/week). We also exposed Wistar rats to air or intoxicating alcohol levels in vapor chambers for 14-h/day for 7 weeks. We then tested the groups of rats for acquisition of cocaine self-administration using ascending cocaine doses (0.125, 0.25, 0.5, 1.0 mg/kg/infusion) followed by a dose-response curve after acquisition of cocaine self-administration. We then extinguished lever pressing and tested the rats for reinstatement of drug seeking induced by cocaine-paired cues and cocaine priming (0, 2.5, 5, 10 mg/kg, i.p.). Wistar rats consumed moderate amounts of alcohol (4.6 g/kg/24 h), P rats consumed higher amounts of alcohol (7.6 g/kg/24 h), and Wistar rats exposed to alcohol vapor had a mean blood alcohol concentration of 176.2 mg/dl during the last week of alcohol exposure. Alcohol pre-exposure had no effect on cocaine self-administration, extinction responding, and reinstatement of drug seeking. Pre-exposure to moderate, high, or intoxicating levels of alcohol had no effect on cocaine self-administration and relapse to cocaine seeking. Our data do not support the notion that alcohol is a gateway drug to cocaine.
| S-EPMC5506787 | biostudies-literature