Does Caffeine Consumption Influence Postcompetition Sleep in Professional Rugby League Athletes? A Case Study

2021 ◽  
pp. 1-4
Author(s):  
Johnpaul Caia ◽  
Shona L. Halson ◽  
Patrick M. Holmberg ◽  
Vincent G. Kelly
Keyword(s):  
Sleep Duration ◽  
Pearson Correlation ◽  
Rugby League ◽  
Caffeine Intake ◽  
Caffeine Consumption ◽  
Caffeine Concentration ◽  
Previous Night ◽  
Activity Monitors ◽  
The Relationship

Purpose: To examine the sleep of rugby league athletes the night before and following an evening match and to investigate the association between caffeine intake and sleep on the night of competition. Methods: On the night prior to, night of, and night after a professional rugby league match, 15 athletes had their sleep monitored using wrist activity monitors. Additionally, saliva samples were collected 60 minutes before and 30 minutes after the competition to assess salivary caffeine concentration. Differences in sleep across the 3 nights were examined using linear mixed models, and changes were assessed using effect size (ES). Pearson correlation (r) assessed the relationship between salivary caffeine levels and sleep indices. Results: On the night of competition, athletes went to bed later than the night before (P = .00002, ES = 1.84) and night after (P = .0003, ES = 1.49) competition. Consequently, their sleep duration was reduced on the night of competition compared with the previous night (P < .0000003, ES = 2.36) and night after competition (P = .001, ES = 1.53). Postcompetition salivary caffeine concentration was substantially elevated in athletes when compared with precompetition measures (P < .00000001, ES = 4.44), and moderate, nonsignificant correlations were observed between changes in salivary caffeine concentration and delayed bedtime (r = .48, P = .07), increased sleep latency (r = .45, P = .09), decreased sleep duration (r = −.30, P = .28), and reduced sleep efficiency (r = −.34, P = .22). Conclusions: These results demonstrate that evening competition results in sleep disturbance in rugby league athletes, and caffeine supplementation prior to and during competition leads to substantial increases in postcompetition salivary caffeine concentration.

scholarly journals Evaluation of the Relationship between Personality and Conservatism of Investors in the Stock Exchange (Case Study: Insurance Companies)

2021 ◽  
Vol 8 (SPE3) ◽  
Author(s):  
Mahsa Mohseni
Keyword(s):  
Significant Relationship ◽  
Stock Exchange ◽  
Pearson Correlation ◽  
Simple Random Sampling ◽  
Insurance Companies ◽  
Statistical Population ◽  
Pearson Correlation Test ◽  
Correlational Method ◽  
The Relationship

The purpose of this research to "investigate the relationship between personality and conservatism of investors of insurance companies listed on the Tehran Stock Exchange." The present study was applied research in terms of purpose, which has employed a descriptive and correlational method. The statistical population of this research included all people who buy and sell shares of insurance companies listed on the Tehran Stock Exchange. According to Cochran's formula, the sample size was determined as much as 384 people collected by a simple random sampling method. The research instruments were the Conservative Questionnaire based on the Gribel and Leighton (1999) and McCrae and Costa (1985) five-factor personality questionnaire. The questionnaire’s validity was confirmed by 20 experts, and the reliability of all three questionnaires was acceptable for all three questionnaires due to Cronbach's alpha above 0.79. The data analysis was conducted using the Pearson correlation test and regression analysis. The results indicated a significant relationship between the investors’ personality and their conservatism in the Tehran Stock Exchange. There was also a significant relationship between all personality components except for extraversion with the investor’s conservatism in the Tehran Stock Exchange.

The relationship of caffeinated beverages with depressive symptoms and decision-making

2021 ◽  
pp. 1-10
Author(s):  
Hatice Çolak ◽  
Emel Erdeniz ◽  
Esra Tansu Sarıyer ◽  
Ekin Çevik ◽  
Didem Yangın
Keyword(s):  
Decision Making ◽  
Depressive Symptoms ◽  
Linear Regression Analysis ◽  
Cross Sectional Study ◽  
Caffeine Intake ◽  
Caffeine Consumption ◽  
Cross Sectional ◽  
Decision Making Styles ◽  
Intuitive Decision Making ◽  
The Relationship

BACKGROUND: Caffeine can affect depressive symptoms and decision-making. OBJECTIVE: This study aims to examine the relationship between caffeinated beverages consumption with depressive symptoms and decision-making styles. METHODS: This cross-sectional study was conducted with 432 adults working in office environment. The questionnaire consisting of individuals’ socio-demographic attributes, the frequency and the amount of caffeinated beverages consumption, the “Epidemiological Research Center-Depression (CES-D) Scale” and the “Decision-Making Styles Scale” were used. The frequency and amount of caffeinated beverages were determined using the food frequency questionnaire (FFQ). The participants were asked to choose which cup/mug they prefer to drink their caffeinated beverages and what amount they consume that beverage at a time. All the data were collected using online platforms. RESULTS: In the study, 76.7%of the participants were female and the mean age was 31.5±8.0 years. The average daily total caffeine intake of the participants was 425.8±461.4 mg and the total CES-D scale score was 17.7±11.2 points. It was found that as the amount of caffeine consumed increased, intuitive decision-making decreased and depressive symptoms increased (p <  0.05). In linear regression analysis, total caffeine consumption was found to be a significant predictor for the intuitive decision-making score (B: –0.151; p:0.002). When caffeine consumption is controlled, intuitive and rational decision making decreases with increasing depressive symptoms while addiction and avoidance decision making increased (p <  0.05). CONCLUSIONS: As a result, the amount of caffeine consumed daily was related to intuitive decision-making but did not effect depression. It has been observed that depressive symptoms affect decision-making styles in different ways. To our knowledge, our study is the first to examine the effects of caffeine consumption on depression and decision-making styles. Accordingly, future studies may focus on the link between caffeine consumption, depression, and decision-making styles in larger populations and the mechanisms that influence this relationship.

Evaluation of Cultural Intelligence in Staff of Industries, Mines and Trades Organizations - Case Study

2017 ◽  
pp. 429-438
Author(s):  
Mohammad Abdolshah ◽  
Baranak Geranfar ◽  
Eisa Akbari ◽  
Jalil Vaziri
Keyword(s):  
Organizational Culture ◽  
Correlation Coefficient ◽  
Cultural Intelligence ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Statistical Population ◽  
Key Competencies ◽  
The Relationship ◽  
Personnel Department

This article examines one of the key competencies of the 21st century known as cultural intelligence (CQ). This study investigates the relationship between CQ, organizational culture, and the effectiveness of staff in the industry, mine, and trade organizations of Semnan province in Iran. Using correlational analysis, the statistical population includes a total of 103 people from 141 employees based on personnel department documents. Three questionnaires were used to measure the variables and descriptive and deductive statistics were applied to evaluate and analyze the data. The Pearson correlation coefficient and multivariate regression were used in deductive statistics to obtain the results. The findings show there is a significant relationship between CQ, organizational culture, and effectiveness. Among four cultural intelligence factors, only the knowledge of CQ can predict the effectiveness. The calculated correlation coefficient indicates that the creativity factors and communication pattern have the highest correlation coefficients.

scholarly journals Does Caffeine Intake Increase the Incidence of Tinnitus? A Systematic Review

2020 ◽  
Author(s):  
Sattam M. Aljuaid ◽  
Ahmad A. Mirza ◽  
Lura A. Habib ◽  
Lujain A. AlHarthi ◽  
Bashayer M. Alansari ◽  
...  
Keyword(s):  
Systematic Review ◽  
Population Based ◽  
Caffeine Intake ◽  
Contributory Factor ◽  
High Dose ◽  
Caffeine Consumption ◽  
Cross Sectional ◽  
Current Review ◽  
Prospective Cohorts ◽  
The Relationship

Abstract Introduction Excessive caffeine intake has been thought to be a contributory factor for tinnitus. However, there has been no systematic review to elucidate the causal relationship between caffeine intake and the incidence of tinnitus. Objectives We performed the current review aiming at evaluating the evidence from the current literature for the relationship between caffeine intake and the incidence of tinnitus. Data Synthesis Databases including PubMed, Scopus, and Google scholar were searched for relevant articles. A total of 142 studies were screened for eligibility, of which four articles met our inclusion criteria: two were prospective cohorts and two were cross-sectional studies. Although one study found no association between caffeine consumption and the incidence of tinnitus, an inverse relationship was reported by two population-based studies. Concerning patients with preexisting tinnitus, reduction of caffeine intake in a subset who consumed 150 ml to 300 ml/day of coffee yielded a favorable outcome in tinnitus severity. However, those with higher dose intake were less prone to have improvement in the severity of tinnitus. Conclusion Although the current review was inconclusive, it appears that the incidence of tinnitus in previously unaffected individuals might be prevented by a high dose of caffeine intake. However, in preexisting tinnitus, a high dose of caffeine may adversely interfere with the efficacy of caffeine reduction.

Caffeine and blood pressure: a critical review perspective

2019 ◽  
Vol 32 (2) ◽  
pp. 169-175 ◽  
Author(s):  
Rachele De Giuseppe ◽  
Ilaria Di Napoli ◽  
Francesca Granata ◽  
Antonia Mottolese ◽  
Hellas Cena
Keyword(s):  
Blood Pressure ◽  
Causes Of Death ◽  
Considerable Increase ◽  
Caffeine Intake ◽  
Caffeine Consumption ◽  
Several Variables ◽  
Caffeine Metabolism ◽  
Methodological Aspects ◽  
The Relationship

AbstractThe WHO reported that high blood pressure (BP) is one of the primary causes of death worldwide. Hypertension (HPT) is a major risk factor for CVD and related diseases as well as for diseases, leading to a considerable increase in cardiovascular risk. Since BP response could also be influenced by caffeine, which is widely consumed with coffee and other items, it is important to define the possible effects associated with caffeine intake. The most recent findings aimed at clarifying the role of caffeine consumption on BP and HPT risk/incidence are conflicting and difficult to interpret. Therefore, in the present narrative review, we aimed to examine various methodological inaccuracies/aspects and factors that make studies difficult to be compared, in order to obtain a single consensus on the effects of caffeine intake on the risk of BP and HPT. We observed that this heterogeneity in results could be due to the presence of: (i) several variables affecting BP (such as age, sex, genetic and lifestyle aspects); (ii) different caffeine content of food and beverages; and (iii) caffeine metabolism. Moreover, different methodological aspects in the evaluation of daily dietary caffeine intake and in the BP measurement could add some other bias in the interpretation of results. Therefore, it is mandatory to consider all methodological aspects and confounding factors to generate a standardised methodology in order to increase cross-study consistency and minimise confounding effects of different variables on the relationship between BP response and HPT risk/incidence after caffeine intake.

scholarly journals DOES THE SHADOW ECONOMY AFFECT FOREIGN DIRECT INVESTMENT? CASE STUDY OF POLAND AND POLISH REGIONS

2021 ◽  
pp. 22-39
Author(s):  
Andrzej Buszko
Keyword(s):  
Foreign Direct Investment ◽  
Direct Investment ◽  
Shadow Economy ◽  
Pearson Correlation ◽  
Positive Association ◽  
Correlation Index ◽  
Regional Associations ◽  
The Relationship ◽  
Mimic Approach

The main goal of the research was to identify the relationship between the level of shadow economy and Foreign Direct Investment. The research was carried in Poland and Polish regions during 1990-2020. MIMIC approach was employed to calculate the level of shadow economy as a % of Polish and regional GDP. Pearson correlation index and Kolmogrov-Smirnov test were applied as well. The study proved there is a sound negative correlation (-0,636) between the shadow economy and foreign direct investment in Poland, but regional associations between those two variables demonstrated different results. Unlike in other Polish provinces, in Opolskie and Podkarpackie the correlation index confirmed a positive association between the level of shadow economy and FDI flow.

scholarly journals P144 Sleep-Related Limb Movements and Subjective Sleepiness in a Professional Rugby League Team

2021 ◽  
Vol 2 (Supplement_1) ◽  
pp. A68-A68
Author(s):  
P Teuwen ◽  
M Dalman ◽  
A Scott
Keyword(s):  
Daytime Sleepiness ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Rugby League ◽  
Significant Relationships ◽  
Normality Test ◽  
Parametric Data ◽  
Subjective Sleepiness ◽  
Movement Parameters ◽  
The Relationship

Abstract Introduction This study aims to assess the relationship between LMs, PLMD and limb related arousals during sleep and subjective sleepiness in a group of professional athletes (National Rugby League (NRL) players). Methods 25 type II HSAT polysomnographic (PSG) studies were performed on 23 male individuals (2 repeated studies). 2 x Piezo limb EMG sensors were applied to each HSAT. PSG data analysed as per AASM Manual for the Scoring of Sleep and Associated events. Epworth Sleepiness Scale (ESS) collected for each participant obtaining subjective daytime sleepiness. PSG data was checked for normality using the Shapiro-Wilk normality test. Parametric data was then subsequently analysed using Pearson correlation coefficients, whereas non-parametric data was analysed with the Spearman correlation coefficient. A line of best fit was implemented using Deming’s linear regression model to report r2. Results The most significant relationships were noted between daytime sleepiness and the frequency of limb-related arousals (Pearson’s r 0.273) and the relationship between PLM arousals and ESS (p-0.082). No significant relationships were noted between LMs, PLMs, limb related arousals and daytime sleepiness were found. No results were found to be statistically significant. Conclusions This PSG data demonstrates a mildly positive correlation with all limb movement parameters measured against the athletes’ self-reported sleepiness. This may therefore be of significance with their performance and recovery. Further research is recommended to verify these relationships.

Does Caffeine Consumption Increase the Risk of New-Onset Atrial Fibrillation?

Cardiology ◽  
2018 ◽  
Vol 140 (2) ◽  
pp. 106-114 ◽  
Author(s):  
Ramy Abdelfattah ◽  
Haroon Kamran ◽  
Jason Lazar ◽  
John Kassotis
Keyword(s):  
Atrial Fibrillation ◽  
Lower Incidence ◽  
Meta Analysis ◽  
Coffee Consumption ◽  
Caffeine Intake ◽  
Response Analysis ◽  
Daily Consumption ◽  
Caffeine Consumption ◽  
Significant Difference ◽  
The Relationship

Objective: Caffeine has been considered a trigger for atrial fibrillation (AF). We conducted a meta-analysis including a dose-response analysis to assess the relationship between caffeine consumed and incidence of AF. Methods: Data from selected studies represented 176,675 subjects (AF in 9,987 [5.7%]). Caffeine content varied widely, ranging from 40 to 180 mg per cup of coffee. For purposes of the calculations in this study, we assumed 140 mg of caffeine in a standard 12-oz cup of coffee. Results: No significant difference was found in AF incidence when the subjects consuming less than 2 cups of coffee per day were compared to subjects with higher consumption, 1.068 (0.937–1.216). The risk of AF was higher among subjects consuming less than 2 cups of coffee daily when compared to higher daily consumption subjects. A lower incidence of AF was found among people consuming more than 436 mg daily. Conclusion: The incidence of AF is not increased by coffee consumption. In fact, we found a lower incidence of AF when caffeine consumption exceeded 436 mg/day. Therefore, based on available evidence there is no association between caffeine intake and AF risk.

scholarly journals Caffeine Consumption among Zayed University Students in Dubai, United Arab Emirates: A Cross-Sectional Study

2017 ◽  
Vol 1 (3) ◽  
pp. 131
Author(s):  
Rola M. Al Ghali ◽  
Hessa Al Shaibi ◽  
Huda Al Majed ◽  
Dalia Haroun
Keyword(s):  
University Students ◽  
United Arab Emirates ◽  
Caffeine Intake ◽  
Perceived Benefits ◽  
Caffeine Consumption ◽  
Gulf Region ◽  
Design Data ◽  
Average Intake ◽  
Males And Females ◽  
The Relationship

Background: Over the past decade, the global caffeine consumption rate has increased dramatically. Coffee and tea are among the common sources, but energy drinks are becoming an important contributor to total caffeine consumption. Recommendations for daily caffeine intake is not being followed due to the perceived benefits of caffeine which include mood improvement, concentration, social factors, and energy boosting. This study was important to add to the limited data about caffeine consumption in the Gulf region and mainly in the UAE.Objectives: The objectives were to determine the prevalence of caffeinated beverage consumption among university students and perceived benefits in addition to the estimation of daily caffeine consumption (mg/day).Design: Data was collected through a self-reported questionnaire from a total of 175 participants (129 females and 46 males) who were conveniently selected from different settings at Zayed University - Dubai. Usual Caffeine intake was calculated from all caffeine containing beverages.  Results: Eighty-six percent of the 175 participants, both males and females, at Zayed University-Dubai consumed caffeinated beverages with an average intake of 249.7±235.9 mg. The intake among the 150 caffeine consumers varied from 4.2 mg/day to 932.2 mg/day. Average intake of caffeine was not significantly different between genders (P=0.125). Thirty-five percent of the population consumed more than 400 mg/day of caffeine, with no statistical difference between males and females (P=0.202). Coffee was the most commonly consumed drink among both genders, followed by tea. Most perceived benefits of caffeine consumption were not significantly different except for the relationship between caffeine and improved exercise performance (P=0.018) and caffeine in relation to weight loss (P=0.001) among males.Conclusion: The prevalence of caffeine consumption at Zayed University was high among both males and females. Further research is necessary to estimate the total caffeine intake from all dietary sources, mainly the cultural foods and beverages, and to determine the relationship between accessibility to caffeine containing beverages and caffeine consumption among University student.

Evaluation of Cultural Intelligence in Staff of Industries, Mines and Trades Organizations - Case Study

2016 ◽  
Vol 4 (2) ◽  
pp. 1-10
Author(s):  
Mohammad Abdolshah ◽  
Baranak Geranfar ◽  
Eisa Akbari ◽  
Jalil Vaziri
Keyword(s):  
Organizational Culture ◽  
Correlation Coefficient ◽  
Cultural Intelligence ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Statistical Population ◽  
Key Competencies ◽  
The Relationship ◽  
Personnel Department

This article examines one of the key competencies of the 21st century known as cultural intelligence (CQ). This study investigates the relationship between CQ, organizational culture, and the effectiveness of staff in the industry, mine, and trade organizations of Semnan province in Iran. Using correlational analysis, the statistical population includes a total of 103 people from 141 employees based on personnel department documents. Three questionnaires were used to measure the variables and descriptive and deductive statistics were applied to evaluate and analyze the data. The Pearson correlation coefficient and multivariate regression were used in deductive statistics to obtain the results. The findings show there is a significant relationship between CQ, organizational culture, and effectiveness. Among four cultural intelligence factors, only the knowledge of CQ can predict the effectiveness. The calculated correlation coefficient indicates that the creativity factors and communication pattern have the highest correlation coefficients.

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