scholarly journals Inconsistency in the Ergogenic Effect of Caffeine in Athletes Who Regularly Consume Caffeine: Is It Due to the Disparity in the Criteria That Defines Habitual Caffeine Intake?

Nutrients ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1087 ◽  
Author(s):  
Aleksandra Filip ◽  
Michal Wilk ◽  
Michal Krzysztofik ◽  
Juan Del Coso

Caffeine is the most popular psychoactive substance in the world, and data suggests that it is widely used by athletes before competition to enhance physical and mental performance. The high number of athletes that regularly use caffeine suggests the need to investigate the effect of acute caffeine ingestion in athletes habituated to caffeine. However, most of the studies supporting this claim have used samples of athletes who do not consume caffeine on a regular basis, and with caffeine intake withdrawal prior to the experiments. A search through 19 databases conducted on habitual caffeine users was performed. The results of the studies regarding the ergogenic effect of caffeine in naïve vs. habitual caffeine consumers are contradictory. The diversity of results are likely associated with the use of different thresholds to categorize individuals as naïve or high caffeine consumers. There are no valid and standardized methods to accurately estimate the amount of caffeine ingested per day in athletes. We proposed a classification of athletes that habitually consume caffeine by using dietary questionnaires, and ultimately, to reduce the likelihood of discrepancies caused by the improper qualification of daily caffeine intake in studies directed at the assessment of acute caffeine intake in habitual caffeine consumers.

2021 ◽  
pp. 273-280
Author(s):  
Ewa Malczyk ◽  
Joanna Wyka ◽  
Agata Malczyk ◽  
Katarzyna Larma

Background. Caffeine is the most widespread psychoactive substance in the world. With long-term consumption of caffeinated beverages, there is a high probability of overtaking on caffeine. Objective. The aim of the study was to estimate the consumption of caffeine in the daily caffeine intake of Polish consumers, determine the caffeinated products in the intake of this substance. Materials and methods. The survey was completed by 433 respondents living in Poland. The research tool was the electronic questionnaire, which consisted of: a) questions about personal data and measurement anthropometric and the level of physical activity and smoking; b) questions regarding the portion size and frequency of consumption of coffee, tea, cocoa, chocolate, energy drinks and colacarbonated beverages. Results. The main sources of caffeine in the respondents' diet include: coffee (Me 43.64 mg/d) and tea (Me 37.60 mg/d). Approximately 20% of respondents exceeded the threshold of daily caffeine intake (safety level for children and adolescents up to 3 mg/kg b.w, for adults up to 5.7 mg/kg b.w), considered safe. Conclusions. Respondents who have crossed the safe dose of caffeine intake, should limit the consumption of products being its main source (coffee).


Nutrients ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 732 ◽  
Author(s):  
Juan Del Coso ◽  
Beatriz Lara ◽  
Carlos Ruiz-Moreno ◽  
Juan Salinero

The ergogenicity of caffeine on several exercise and sport situations is well-established. However, the extent of the ergogenic response to acute caffeine ingestion might greatly vary among individuals despite using the same dosage and timing. The existence of one or several individuals that obtained minimal ergogenic effects or even slightly ergolytic effects after caffeine intake (i.e., non-responders) has been reported in several previous investigations. Nevertheless, the concept non-responding to caffeine, in terms of physical performance, relies on investigations based on the measurement of one performance variable obtained once. Recently it has been suggested that correct identification of the individual ergogenic effect induced by caffeine intake requires the repeated measurement of physical performance in identical caffeine–placebo comparisons. In this communication, we present data from an investigation where the ergogenic effect of acute caffeine intake (3 mg/kg) was measured eight times over a placebo in the same individuals and under the same conditions by an incremental cycling test to volitional fatigue and an adapted version of the Wingate cycling test. The ergogenic response to caffeine varied from 9% to 1% among individuals, but all participants increased both cycling power in the incremental test and Wingate mean power at least three to eight times out of eight the caffeine–placebo comparisons. These data expand the suggestion of a minimal occurrence of caffeine non-responders because it shows that all individuals responded to caffeine when caffeine is compared to a placebo on multiple and repeated testing sessions.


Nutrients ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1352 ◽  
Author(s):  
Kyle Southward ◽  
Kay Rutherfurd-Markwick ◽  
Claire Badenhorst ◽  
Ajmol Ali

Caffeine use is widespread among athletes following its removal from the World Anti-Doping Agency banned list, with approximately 75% of competitive athletes using caffeine. While literature supports that caffeine has a small positive ergogenic effect for most forms of sports and exercise, there exists a significant amount of inter-individual difference in the response to caffeine ingestion and the subsequent effect on exercise performance. In this narrative review, we discuss some of the potential mechanisms and focus on the role that genetics has in these differences. CYP1A2 and ADORA2A are two of the genes which are thought to have the largest impact on the ergogenicity of caffeine. CYP1A2 is responsible for the majority of the metabolism of caffeine, and ADORA2A has been linked to caffeine-induced anxiety. The effects of CYP1A2 and ADORA2A genes on responses to caffeine will be discussed in detail and an overview of the current literature will be presented. The role of these two genes may explain a large portion of the inter-individual variance reported by studies following caffeine ingestion. Elucidating the extent to which these genes moderate responses to caffeine during exercise will ensure caffeine supplementation programs can be tailored to individual athletes in order to maximize the potential ergogenic effect.


Author(s):  
Jozo Grgic ◽  
Juan Del Coso

This meta-analysis aimed to explore the effects of caffeine ingestion on muscular endurance and muscular strength in women. Five databases were searched to find relevant studies. A random-effects meta-analysis of standardized mean differences (SMD) was performed for data analysis. Subgroup meta-analyses explored the effects of caffeine on upper-body and lower-body muscular endurance and muscular strength. Eight crossover placebo-controlled studies were included in the review. In the main meta-analysis that considered data from all included studies, there was a significant ergogenic effect of caffeine on muscular endurance (SMD = 0.25; p = 0.027) and muscular strength (SMD = 0.18; p < 0.001). In a subgroup analysis that considered only upper-body exercises, there was a significant ergogenic effect of caffeine on muscular endurance (SMD = 0.20; p = 0.007) and muscular strength (SMD = 0.17; p < 0.001). In a subgroup analysis that considered only lower-body exercises, there was no significant difference between caffeine and placebo for muscular endurance (SMD = 0.43; p = 0.092) or muscular strength (SMD = 0.16; p = 0.109). The main finding of this meta-analysis is that caffeine ingestion has a significant ergogenic effect on muscular endurance and muscular strength in women. The effects reported in this analysis are similar to those previously observed in men and suggest that women may use caffeine supplementation as an ergogenic aid for muscular performance. Future research is needed to explore the effects of caffeine on lower-body muscular endurance and muscular strength in this population.


2003 ◽  
Vol 8 (4) ◽  
pp. 238-251
Author(s):  
Victor F. Petrenko ◽  
Olga V. Mitina ◽  
Kirill A. Bertnikov

The aim of this research was the reconstruction of the system of categories through which Russians perceive the countries of the Commonwealth of Independent States (CIS), Europe, and the world as a whole; to study the implicit model of the geopolitical space; to analyze the stereotypes in the perception of different countries and the superposition of mental geopolitical representations onto the geographic map. The techniques of psychosemantics by Petrenko, originating in the semantic differential of Osgood and Kelly's “repertory grids,” were used as working tools. Multidimensional semantic spaces act as operational models of the structures of consciousness, and the positions of countries in multidimensional space reflect the geopolitical stereotypes of respondents about these countries. Because of the transformation of geopolitical reality representations in mass consciousness, the commonly used classification of countries as socialist, capitalist, and developing is being replaced by other structures. Four invariant factors of the countries' descriptions were identified. They are connected with Economic and Political Well-being, Military Might, Friendliness toward Russia, and Spirituality and the Level of Culture. It seems that the structure has not been explained in adequate detail and is not clearly realized by the individuals. There is an interrelationship between the democratic political structure of a country and its prosperity in the political mentality of Russian respondents. Russian public consciousness painfully strives for a new geopolitical identity and place in the commonwealth of states. It also signifies the country's interest and orientation toward the East in the search for geopolitical partners. The construct system of geopolitical perception also depends on the region of perception.


2009 ◽  
pp. 123-129
Author(s):  
Yu. Golubitsky

The article considers business practices of Moscow small industry in the XIX century, basing upon physiological sketches of N. Polevoy and I. Kokorev, statistical data and the classification of professions are also presented. The author claims that the heroes of the analyzed sketches are the forefathers of Moscow small businesses and shows what a deep similarity their occupations and a way of life bear to the present-day routine existence of small enterprises.


2020 ◽  
Vol 7 (2) ◽  
pp. 419-436
Author(s):  
Olga Igorevna Severskaya

The article is devoted to the consideration of a poetic text as a communicative phenomenon with a high impact potential. The author defines the features of poetic communication, which is both mass and interpersonal, and its main goal, which is the poet’s desire to communicate author’s vision of the world and thereby change the picture of the reader’s world, achieving empathy from it. Based on the understanding of the speech strategy as a cognitive communication plan, a program for generating and perceiving speech, the author talks about the fundamental reversibility of text-generating and interpretative strategies and offers own classification of strategies and tactics that are most often used in modern poetry. In this classification, the main communicative strategies of self-presentation and rapprochement with the reader are associated with auxiliary discursive strategies of actualizing, dramatizing and dialogizing the text and programming interpretations by tactics for highlighting objects and situations using sound “gestures”, pointing to the referent, framing, directly introducing the reader into the communicative context, attracting the recipient’s attention through appeals and pragmatic instructions, interrogation, and some others. Particular attention is paid to the multimodality of interactions and its specific manifestations in poetic discourse. The study is based on the material of Russian poetry of the 1980- 2000s using the methods of intent and discourse analysis.


ARTic ◽  
2019 ◽  
Vol 4 ◽  
pp. 167-176
Author(s):  
Risti Puspita Sari Hunowu

This research is aimed at studying the Hunto Sultan Amay Mosque located in Gorontalo City. Hunto Sultan Amay Mosque is the oldest mosque in the city of Gorontalo The Hunto Sultan Amay Mosque was built as proof of Sultan Amay's love for a daughter and is a representation of Islam in Gorontalo. Researchers will investigate the visual form of the Hunto Sultan Amay Mosque which was originally like an ancient mosque in the archipelago. can be seen from the shape of the roof which initially used an overlapping roof and then converted into a dome as well as mosques in the world, we can be sure the Hunto Sultan Amay Mosque uses a dome roof after the arrival of Dutch Colonial. The researcher used a qualitative method by observing the existing form in detail from the building of the mosque with an aesthetic approach, reviewing objects and selecting the selected ornament giving a classification of the shapes, so that the section became a reference for the author as research material. Based on the analysis of this thesis, the form  of the Hunto Sultan Amay mosque as well as the mosques located in the archipelago and the existence of ornaments in the Hunto Sultan Amay Mosque as a decorative structure support the grandeur of a mosque. On the other hand, Hunto Mosque ornaments reveal a teaching. The form of a teaching is manifested in the form of motives and does not depict living beings in a realist or naturalist manner. the decorative forms of the Hunto Sultan Sultan Mosque in general tend to lead to a form of flora, geometric ornaments, and ornament of calligraphy dominated by the distinctive colors of Islam, namely gold, white, red, yellow and green.


2020 ◽  
pp. 65-75
Author(s):  
S. N. Smirnov

The author considers the problems of typification of society. Some concepts of typification of social stratification models in different countries formulated and justified in historical and legal, historical, sociological, and economic scientific literature are reviewed. The circumstances that make it difficult to formulate universal concepts designed for application in the complex of social Sciences are identified. These circumstances include insufficient consideration of legal factors, including the position of the legislator, the specifics of the corporate legal status, and the characteristics of the mechanism for changing individual legal status. The author offers a variant of classification of society types from the point of view of legal registration of their structure. The possibility of distinguishing types such as consolidated companies and segmented companies is justified.


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