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Strunge K, Bostock H, Howells J, Cengiz B, Samusyte G, Koltzenburg M, Tankisi H. Caffeine and cortical excitability, as measured with paired-pulse transcranial magnetic stimulation. Muscle Nerve 2024; 69:206-212. [PMID: 38124685 DOI: 10.1002/mus.28027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 11/27/2023] [Accepted: 12/12/2023] [Indexed: 12/23/2023]
Abstract
INTRODUCTION/AIMS The transcranial magnetic stimulation tests of short-interval intracortical inhibition (SICI) by both conventional amplitude measurements (A-SICI) and threshold-tracking (T-SICI) are important methods to investigate intracortical inhibitory circuits, and T-SICI has been proposed to aid the diagnosis of amyotrophic lateral sclerosis. Beverages containing caffeine are widely consumed, and caffeine has been reported to affect cortical excitability. The aim of this study was to determine whether these SICI tests are affected by caffeine. METHODS Twenty-four healthy subjects (13 females, 11 males, aged from 19 to 31, mean: 26.2 ± 2.4 years) were studied in a single fixed-dose randomized double-blind placebo-controlled cross-over trial of 200 mg caffeine or placebo ingested as chewing gum. A-SICI and T-SICI, using parallel tracking (T-SICIp), were performed before and after chewing gum. RESULTS There was no significant change in SICI parameters after placebo in A-SICI (p > .10) or T-SICIp (p > .30), and no significant effect of caffeine was found on A-SICI (p > .10) or T-SICIp (p > .50) for any of the interstimulus intervals. DISCUSSION There is no need for caffeine abstention before measurements of SICI by either the T-SICI or A-SICI measurements.
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Affiliation(s)
- Kristine Strunge
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
| | - Hugh Bostock
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
| | - James Howells
- Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - Bülent Cengiz
- Department of Neurology, Gazi University Faculty of Medicine, Ankara, Turkey
| | - Gintaute Samusyte
- Department of Neurology, Hospital of Lithuanian University of Health Sciences Kauno Klinikos, Kaunas, Lithuania
- Department of Neurology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Martin Koltzenburg
- Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, London, UK
| | - Hatice Tankisi
- Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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Pirmohammadi S, Hemmatinafar M, Nemati J, Imanian B, Abdollahi MH. Early absorption sources of caffeine can be a useful strategy for improving female table tennis players-specific performance. J Int Soc Sports Nutr 2023; 20:2282051. [PMID: 37974406 PMCID: PMC11018319 DOI: 10.1080/15502783.2023.2282051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND The consumption of fast absorption sources containing caffeine, such as caffeinated gum and coffee mouth rinsing, has been considered a practical nutritional strategy among athletes. Therefore, this study aimed to determine the effect of early absorption sources containing caffeine on the performance of female table tennis players. METHOD Eighteen female table tennis players randomly participated in this randomized, double-blind, and crossover designed study. Before starting the test, the participants attended a familiarization session. In each test session, participants were randomly assigned to one of three conditions including chewing caffeinated gum (CG, n = 6), coffee mouth rinsing (CMR, n = 6) and placebo capsule (PLA, n = 6). All participants consumed caffeine with an average dose of ∼3 to 4.5 mg·kg-1. The one-week interval was considered a washout period for each condition. Each test session included measurement of functional, skill and cognitive tests. Skill tests included serve, forehand drive, backhand push and counter tests. The Cognitive function measured by color recognition test, and functional tests included agility, hand movement speed, the explosive power of the upper body and lower body, hand-eye coordination and hand grip strength tests. The collected data were analyzed (with SPSS Windows software) by repeated measure ANOVA analysis and Bonferroni post hoc test at P ≤ 0.05 level. RESULTS The findings of the present study illustrated that CG and CMR increased significantly agility and reduced the amounts of errors in the cognitive test compared to PLA (p < 0.05), While there was no significant difference between CG and CMR (p > 0.05). Also, CG and CMR compared to PLA and CMR compared to CG rose significantly hand movement speed and movement speed (p < 0.05), and CMR compared to PLA increased significantly hand-eye coordination, isometric hand strength, service accuracy and forehand drive (p < 0.05). However, CG compared to PLA and CMR had no significant effect on hand-eye coordination, isometric hand strength, service accuracy and forehand drive (p > 0.05). In addition, CG and CMR enhanced significantly the explosive power of the lower body compared to PLA (p < 0.05), While there was no significant difference between CG and CMR (p > 0.05). Also, CG and CMR compared to PLA and CG compared to CMR had no significant effect on the explosive power of the upper body, backhand, and counter skills (p > 0.05). Furthermore, CG increased significantly accuracy in the service test compared to PLA (p < 0.05). CONCLUSION According to the results, it seems that early absorption sources of caffeine (CMR and CG) are efficient strategies for improving the specific performance of female table tennis players. However, allegedly CMR and CG have a better effect on functional and cognitive tests compared to skill tests.
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Affiliation(s)
- Sepideh Pirmohammadi
- Department of Sport Sciences, Faculty of Education and Psychology, Shiraz University, Shiraz, Iran
| | - Mohammad Hemmatinafar
- Department of Sport Sciences, Faculty of Education and Psychology, Shiraz University, Shiraz, Iran
| | - Javad Nemati
- Department of Sport Sciences, Faculty of Education and Psychology, Shiraz University, Shiraz, Iran
| | - Babak Imanian
- Department of Sport Sciences, Faculty of Education and Psychology, Shiraz University, Shiraz, Iran
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Halverson T, Myers CW, Gearhart JM, Linakis MW, Gunzelmann G. Physiocognitive Modeling: Explaining the Effects of Caffeine on Fatigue. Top Cogn Sci 2022; 14:860-872. [DOI: 10.1111/tops.12615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 04/13/2022] [Accepted: 05/03/2022] [Indexed: 11/28/2022]
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Shephard A, Barrett SP. The impacts of caffeine administration, expectancies, and related stimuli on coffee craving, withdrawal, and self-administration. J Psychopharmacol 2022; 36:378-386. [PMID: 34278878 PMCID: PMC8905124 DOI: 10.1177/02698811211032447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Caffeine is the most commonly consumed psychoactive substance, yet its potential reinforcing properties have been understudied. AIMS This study examined the impact of caffeine administration and expectancy on coffee-related craving, withdrawal, and cue reactivity via a balanced-placebo design. METHODS Following 18-h caffeine abstinence, 65 daily coffee consumers (54% male) received either caffeine-containing (100 mg) or placebo gum, along with either accurate or inaccurate information regarding the gum's caffeine content. Participants were exposed to neutral and coffee-related stimuli using different sensory modalities (visual and combined auditory/olfactory). Craving, withdrawal, and heart rate were assessed at baseline and after each cue presentation. Following the cue-reactivity assessments, participants were provided with an opportunity to self-administer units of coffee. RESULTS Caffeine expectancy was associated with reduced subjective withdrawal 30 min following the gum administration but was not significantly impacted by actual caffeine administration. The presentation of coffee-related cues was found to increase self-reported craving and heart rate, regardless of the expectation that caffeine had been administered. Visual, but not auditory/olfactory, cue reactivity appeared blunted when participants received a prior dose of caffeine. Prior caffeine ingestion also reduced the probability of subsequent coffee self-administration. CONCLUSION To our knowledge, this is the first examination of the impact of caffeine administration and expectancy on cue-elicited coffee craving and coffee consumption. Although there was some evidence that caffeine expectancy and administration were found to impact subjective withdrawal and self-administration respectively, neither was found to exert strong consistent effects on cue reactivity.
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Affiliation(s)
- Aaron Shephard
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada
| | - Sean P Barrett
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada
- Department of Psychiatry, Dalhousie University, Halifax, NS, Canada
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Grzegorzewski J, Bartsch F, Köller A, König M. Pharmacokinetics of Caffeine: A Systematic Analysis of Reported Data for Application in Metabolic Phenotyping and Liver Function Testing. Front Pharmacol 2022; 12:752826. [PMID: 35280254 PMCID: PMC8914174 DOI: 10.3389/fphar.2021.752826] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 12/03/2021] [Indexed: 01/13/2023] Open
Abstract
Caffeine is by far the most ubiquitous psychostimulant worldwide found in tea, coffee, cocoa, energy drinks, and many other beverages and food. Caffeine is almost exclusively metabolized in the liver by the cytochrome P-450 enzyme system to the main product paraxanthine and the additional products theobromine and theophylline. Besides its stimulating properties, two important applications of caffeine are metabolic phenotyping of cytochrome P450 1A2 (CYP1A2) and liver function testing. An open challenge in this context is to identify underlying causes of the large inter-individual variability in caffeine pharmacokinetics. Data is urgently needed to understand and quantify confounding factors such as lifestyle (e.g., smoking), the effects of drug-caffeine interactions (e.g., medication metabolized via CYP1A2), and the effect of disease. Here we report the first integrative and systematic analysis of data on caffeine pharmacokinetics from 141 publications and provide a comprehensive high-quality data set on the pharmacokinetics of caffeine, caffeine metabolites, and their metabolic ratios in human adults. The data set is enriched by meta-data on the characteristics of studied patient cohorts and subjects (e.g., age, body weight, smoking status, health status), the applied interventions (e.g., dosing, substance, route of application), measured pharmacokinetic time-courses, and pharmacokinetic parameters (e.g., clearance, half-life, area under the curve). We demonstrate via multiple applications how the data set can be used to solidify existing knowledge and gain new insights relevant for metabolic phenotyping and liver function testing based on caffeine. Specifically, we analyzed 1) the alteration of caffeine pharmacokinetics with smoking and use of oral contraceptives; 2) drug-drug interactions with caffeine as possible confounding factors of caffeine pharmacokinetics or source of adverse effects; 3) alteration of caffeine pharmacokinetics in disease; and 4) the applicability of caffeine as a salivary test substance by comparison of plasma and saliva data. In conclusion, our data set and analyses provide important resources which could enable more accurate caffeine-based metabolic phenotyping and liver function testing.
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Guest NS, VanDusseldorp TA, Nelson MT, Grgic J, Schoenfeld BJ, Jenkins NDM, Arent SM, Antonio J, Stout JR, Trexler ET, Smith-Ryan AE, Goldstein ER, Kalman DS, Campbell BI. International society of sports nutrition position stand: caffeine and exercise performance. J Int Soc Sports Nutr 2021; 18:1. [PMID: 33388079 PMCID: PMC7777221 DOI: 10.1186/s12970-020-00383-4] [Citation(s) in RCA: 193] [Impact Index Per Article: 64.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 10/31/2020] [Indexed: 12/13/2022] Open
Abstract
Following critical evaluation of the available literature to date, The International Society of Sports Nutrition (ISSN) position regarding caffeine intake is as follows: 1. Supplementation with caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions. 2. Aerobic endurance appears to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use, although the magnitude of its effects differs between individuals. 3. Caffeine has consistently been shown to improve exercise performance when consumed in doses of 3-6 mg/kg body mass. Minimal effective doses of caffeine currently remain unclear but they may be as low as 2 mg/kg body mass. Very high doses of caffeine (e.g. 9 mg/kg) are associated with a high incidence of side-effects and do not seem to be required to elicit an ergogenic effect. 4. The most commonly used timing of caffeine supplementation is 60 min pre-exercise. Optimal timing of caffeine ingestion likely depends on the source of caffeine. For example, as compared to caffeine capsules, caffeine chewing gums may require a shorter waiting time from consumption to the start of the exercise session. 5. Caffeine appears to improve physical performance in both trained and untrained individuals. 6. Inter-individual differences in sport and exercise performance as well as adverse effects on sleep or feelings of anxiety following caffeine ingestion may be attributed to genetic variation associated with caffeine metabolism, and physical and psychological response. Other factors such as habitual caffeine intake also may play a role in between-individual response variation. 7. Caffeine has been shown to be ergogenic for cognitive function, including attention and vigilance, in most individuals. 8. Caffeine may improve cognitive and physical performance in some individuals under conditions of sleep deprivation. 9. The use of caffeine in conjunction with endurance exercise in the heat and at altitude is well supported when dosages range from 3 to 6 mg/kg and 4-6 mg/kg, respectively. 10. Alternative sources of caffeine such as caffeinated chewing gum, mouth rinses, energy gels and chews have been shown to improve performance, primarily in aerobic exercise. 11. Energy drinks and pre-workout supplements containing caffeine have been demonstrated to enhance both anaerobic and aerobic performance.
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Affiliation(s)
- Nanci S Guest
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, 1 King's College Circle, Room 5326A, Toronto, ON, M5S 1A8, Canada.
| | - Trisha A VanDusseldorp
- Department of Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA, 30144, USA
| | | | - Jozo Grgic
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia
| | - Brad J Schoenfeld
- Department of Health Sciences, CUNY Lehman College, Bronx, NY, 10468, USA
| | - Nathaniel D M Jenkins
- Department of Health and Human Physiology, University of Iowa, Iowa City, IA, 52240, USA
| | - Shawn M Arent
- Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Colombia, SC, 29208, USA
- School of Social and Health Sciences, Leeds Trinity University, Leeds, UK
| | - Jose Antonio
- Exercise and Sport Science, Nova Southeastern University, Davie, FL, 33314, USA
| | - Jeffrey R Stout
- Institue of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, 32816, USA
| | | | - Abbie E Smith-Ryan
- Department of Exercise and Sport Science, Applied Physiology Laboratory, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Erica R Goldstein
- Institue of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, 32816, USA
| | - Douglas S Kalman
- Nutrion Department, College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL, 33314, USA
- Scientific Affairs. Nutrasource, Guelph, ON, Canada
| | - Bill I Campbell
- Performance & Physique Enhancement Laboratory, University of South Florida, Tampa, FL, 33612, USA
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Daneshfar A, Petersen CJ, Koozehchian MS, Gahreman DE. Caffeinated Chewing Gum Improves Bicycle Motocross Time-Trial Performance. Int J Sport Nutr Exerc Metab 2020; 30:427-434. [PMID: 32932231 DOI: 10.1123/ijsnem.2020-0126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 08/11/2020] [Accepted: 08/11/2020] [Indexed: 11/18/2022]
Abstract
This study aimed to identify the acute effects of caffeinated chewing gum (CAF) on bicycle motocross (BMX) time-trial (TT) performance. In a randomized, placebo-controlled, double-blind cross-over design, 14 male BMX riders (age = 20.0 ± 3.3 years; height = 1.78 ± 0.04 m; body mass = 72 ± 4 kg), consumed either (300 mg; 4.2 ± 0.2 mg/kg) caffeinated (300 mg caffeine, 6 g sugars) or a placebo (0 mg caffeine, 0 g sugars) gum, and undertook three BMX TTs. Repeated-measure analysis revealed that CAF has a large ergogenic effect on TT time, F(1, 14) = 33.570, p = .001, ηp2=.71; -1.5% ± 0.4 compared with the placebo. Peak power and maximal power to weight ratio also increased significantly compared with the placebo condition, F(1, 14) = 54.666, p = .001, ηp2=.79; +3.5% ± 0.6, and F(1, 14) = 57.399, p = .001, ηp2=.80; +3% ± 0.3, respectively. Rating of perceived exertion was significantly lower F(1, 14) = 25.020, p = .001, ηp2=.64 in CAF (6.6 ± 1.3) compared with the placebo (7.2 ± 1.7). Administering a moderate dose (300 mg) of CAF could improve TT time by enhancing power and reducing the perception of exertion. BMX coaches and riders may consider consuming CAF before a BMX race to improve performance and reduce rating of perceived exertion.
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Potter GDM, Wood TR. The Future of Shift Work: Circadian Biology Meets Personalised Medicine and Behavioural Science. Front Nutr 2020; 7:116. [PMID: 32850937 PMCID: PMC7426458 DOI: 10.3389/fnut.2020.00116] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 06/22/2020] [Indexed: 12/15/2022] Open
Abstract
Shift work is commonplace in modern societies, and shift workers are predisposed to the development of numerous chronic diseases. Disruptions to the circadian systems of shift workers are considered important contributors to the biological dysfunction these people frequently experience. Because of this, understanding how to alter shift work and zeitgeber (time cue) schedules to enhance circadian system function is likely to be key to improving the health of shift workers. While light exposure is the most important zeitgeber for the central clock in the circadian system, diet and exercise are plausible zeitgebers for circadian clocks in many tissues. We know little about how different zeitgebers interact and how to tailor zeitgeber schedules to the needs of individuals; however, in this review we share some guidelines to help shift workers adapt to their work schedules based on our current understanding of circadian biology. We focus in particular on the importance of diet timing and composition. Going forward, developments in phenotyping and "envirotyping" methods may be important to understanding how to optimise shift work. Non-invasive, multimodal, comprehensive phenotyping using multiple sources of time-stamped data may yield insights that are critical to the care of shift workers. Finally, the impact of these advances will be reduced without modifications to work environments to make it easier for shift workers to engage in behaviours conducive to their health. Integrating findings from behavioural science and ergonomics may help shift workers make healthier choices, thereby amplifying the beneficial effects of improved lifestyle prescriptions for these people.
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Affiliation(s)
| | - Thomas R Wood
- Division of Neonatology, Department of Pediatrics, University of Washington, Seattle, WA, United States.,Division of Human Health, Performance and Resilience, Institute for Human and Machine Cognition, Pensacola, FL, United States
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Killgore WDS, Kamimori GH. Multiple caffeine doses maintain vigilance, attention, complex motor sequence expression, and manual dexterity during 77 hours of total sleep deprivation. Neurobiol Sleep Circadian Rhythms 2020; 9:100051. [PMID: 33364521 PMCID: PMC7752712 DOI: 10.1016/j.nbscr.2020.100051] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 05/24/2020] [Accepted: 05/27/2020] [Indexed: 12/25/2022] Open
Abstract
Sleep deprivation (SD) and fatigue have detrimental effects on performance in operational settings. Few studies have investigated the cumulative effects of SD and fatigue on performance under heavy workload demands. Therefore, we investigated the efficacy of multiple repeated doses of caffeine as a countermeasure to SD and fatigue during 77 h total SD (TSD) during the early morning hours. Twenty-three males and females, 18 – 35 years of age, who identified as moderate caffeine consumers completed the Psychomotor Vigilance Task (PVT) 141 times during the experimental test period. Caffeine was administered in a multi-dose paradigm over three nights without sleep. Participants received either caffeine (200 mg) or placebo at the beginning of each 2-h test block from 0100 – 0900 (800 mg total per night). While PVT speed declined for both groups across all 3 nights, the caffeine group consistently out-performed the placebo group. Caffeine maintained attentiveness (1-5 s lapses) on night 1, but this advantage was lost on nights 2 and 3. Caffeine outperformed placebo for responsive lapses (5-9 s lapses) across all three nights, but caffeine performance was still notably worse than at baseline. Prolonged non-responsive lapses (beyond 10 s) were only reduced by caffeine on night 2. Caffeine was more effective than placebo across all nights at sustaining completion speed of a complex motor sequence task and a manual coordination task. Essentially, caffeine is an effective countermeasure for SD, as it mitigates declines in speed and failures to respond, and sustains motor planning and coordination. However, caffeine does not restore normal functioning during SD and cannot be considered as a replacement for sleep. Compared caffeine versus placebo during extreme sleep deprived monotony. Caffeine improved psychomotor vigilance speed and reduced lapses of all durations. Caffeine did not maintain normal performance after the first night of sleep loss. Caffeine sustained motor planning and coordination better than placebo. Caffeine mitigates sleep loss deficits but does not sustain performance at normal.
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Affiliation(s)
- William D S Killgore
- Department of Behavioral Biology, Walter Reed Army Institute of Research, USA.,Department of Psychiatry, University of Arizona College of Medicine, USA
| | - Gary H Kamimori
- Department of Behavioral Biology, Walter Reed Army Institute of Research, USA
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Ueno H, Takahashi Y, Suemitsu S, Murakami S, Kitamura N, Wani K, Matsumoto Y, Okamoto M, Ishihara T. Caffeine inhalation effects on locomotor activity in mice. Drug Dev Ind Pharm 2020; 46:788-794. [PMID: 32292092 DOI: 10.1080/03639045.2020.1753064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
It is estimated that 80% of the world's population consumes caffeine from beverages and food every day. The traditional form of caffeine intake is oral, but more recently people have been inhaling caffeine using nasal sprays. However, the effects of caffeine inhalation are not well understood. The purpose of this study was to determine whether caffeine inhalation affects mouse behavior. To test this, we compared spontaneous activity of mice following inhalation and intraperitoneal administration of caffeine. Next, we investigated whether spontaneous activity changed with the time and/or concentration of caffeine inhaled. We found that mice that inhaled caffeine increased their spontaneous activity similar to mice that were administered caffeine intraperitoneally. Furthermore, spontaneous activity increased in an inhalation time-dependent and concentration-dependent manner. These results show that caffeine-induced stimulation also occurs by inhalation in mice, which suggests that caffeine can reach the brain even by inhalation. This study is useful not only for creating new administration methods of caffeine but also for adjusting caffeine storage and management.
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Affiliation(s)
- Hiroshi Ueno
- Department of Medical Technology, Kawasaki University of Medical Welfare, Kurashiki, Okayama, Japan
| | - Yu Takahashi
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Shunsuke Suemitsu
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Shinji Murakami
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Naoya Kitamura
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Kenta Wani
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Yosuke Matsumoto
- Department of Neuropsychiatry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Okayama, Japan
| | - Motoi Okamoto
- Department of Medical Technology, Graduate School of Health Sciences, Okayama University, Okayama, Okayama, Japan
| | - Takeshi Ishihara
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Okayama, Japan
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11
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Pajcin M, White JM, Banks S, Dorrian J, Paech GM, Grant CL, Johnson K, Tooley K, Aidman E, Fidock J, Kamimori GH, Della Vedova CB. Effects of strategic early-morning caffeine gum administration on association between salivary alpha-amylase and neurobehavioural performance during 50 h of sleep deprivation. ACCIDENT; ANALYSIS AND PREVENTION 2019; 126:160-172. [PMID: 29402402 DOI: 10.1016/j.aap.2018.01.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 01/18/2018] [Accepted: 01/18/2018] [Indexed: 06/07/2023]
Abstract
Self-assessment is the most common method for monitoring performance and safety in the workplace. However, discrepancies between subjective and objective measures have increased interest in physiological assessment of performance. In a double-blind placebo-controlled study, 23 healthy adults were randomly assigned to either a placebo (n = 11; 5 F, 6 M) or caffeine condition (n = 12; 4 F, 8 M) while undergoing 50 h (i.e. two days) of total sleep deprivation. In previous work, higher salivary alpha-amylase (sAA) levels were associated with improved psychomotor vigilance and simulated driving performance in the placebo condition. In this follow-up article, the effects of strategic caffeine administration on the previously reported diurnal profiles of sAA and performance, and the association between sAA and neurobehavioural performance were investigated. Participants were given a 10 h baseline sleep opportunity (monitored via standard polysomnography techniques) prior to undergoing sleep deprivation (total sleep time: placebo = 8.83 ± 0.48 h; caffeine = 9.01 ± 0.48 h). During sleep deprivation, caffeine gum (200 mg) was administered at 01:00 h, 03:00 h, 05:00 h, and 07:00 h to participants in the caffeine condition (n = 12). This strategic administration of caffeine gum (200 mg) has been shown to be effective at maintaining cognitive performance during extended wakefulness. Saliva samples were collected, and psychomotor vigilance and simulated driving performance assessed at three-hour intervals throughout wakefulness. Caffeine effects on diurnal variability were compared with previously reported findings in the placebo condition (n = 11). The impact of caffeine on the circadian profile of sAA coincided with changes in neurobehavioural performance. Higher sAA levels were associated with improved performance on the psychomotor vigilance test during the first 24 h of wakefulness in the caffeine condition. However, only the association between sAA and response speed (i.e. reciprocal-transform of mean reaction time) was consistent across both days of sleep deprivation. The association between sAA and driving performance was not consistent across both days of sleep deprivation. Results show that the relationship between sAA and reciprocal-transform of mean reaction time on the psychomotor vigilance test persisted in the presence of caffeine, however the association was relatively weaker as compared with the placebo condition.
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Affiliation(s)
- Maja Pajcin
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, AUS.
| | - Jason M White
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, AUS
| | - Siobhan Banks
- Centre for Sleep Research, University of South Australia, Magill, SA, AUS
| | - Jill Dorrian
- Centre for Sleep Research, University of South Australia, Magill, SA, AUS
| | - Gemma M Paech
- Centre for Sleep Research, University of South Australia, Magill, SA, AUS
| | - Crystal L Grant
- Centre for Sleep Research, University of South Australia, Magill, SA, AUS
| | - Kayla Johnson
- Land Division, Defence Science and Technology Group, Department of Defence, Edinburgh, SA, AUS
| | - Katie Tooley
- Land Division, Defence Science and Technology Group, Department of Defence, Edinburgh, SA, AUS
| | - Eugene Aidman
- Land Division, Defence Science and Technology Group, Department of Defence, Edinburgh, SA, AUS
| | - Justin Fidock
- Land Division, Defence Science and Technology Group, Department of Defence, Edinburgh, SA, AUS
| | - Gary H Kamimori
- Behavioral Biology Branch, Walter Reed Army Institute for Research, Silver Springs, MD, USA
| | - Chris B Della Vedova
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, AUS
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12
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Morris C, Viriot SM, Farooq Mirza QUA, Morris GA, Lynn A. Caffeine release and absorption from caffeinated gums. Food Funct 2019; 10:1792-1796. [PMID: 30919868 DOI: 10.1039/c9fo00431a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The objectives of this study were to estimate the impact of chewing time on caffeine release from gum and to understand caffeine pharmacokinetics. Caffeine release increased with chewing time (2 min < 5 min < 10 min). Furthermore, two plasma caffeine concentration peaks were observed suggesting that caffeine absorption occurs both through the oral mucosa and gastrointestinal tract. This is of practical relevance to maximise caffeine doses and to synchronise effort with peak caffeine concentration.
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Affiliation(s)
- Cecile Morris
- Food and Nutrition Division, Sheffield Hallam University, Howard street, Sheffield, S1 1WB, UK.
| | - Sophie M Viriot
- Food and Nutrition Division, Sheffield Hallam University, Howard street, Sheffield, S1 1WB, UK. and AgroSup Dijon, 26 boulevard Petitjean, BP87999 - 21079 Dijon Cedex, France
| | - Qurat U A Farooq Mirza
- Food and Nutrition Division, Sheffield Hallam University, Howard street, Sheffield, S1 1WB, UK.
| | - Gordon A Morris
- Department of Chemical Sciences, School of Applied Science, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, UK
| | - Anthony Lynn
- Food and Nutrition Division, Sheffield Hallam University, Howard street, Sheffield, S1 1WB, UK.
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Abstract
There has been recent interest in the ergogenic effects of caffeine delivered in low doses (~ 200 mg or ~ 3 mg/kg body mass) and administered in forms other than capsules, coffee and sports drinks, including chewing gum, bars, gels, mouth rinses, energy drinks and aerosols. Caffeinated chewing gum is absorbed quicker through the buccal mucosa compared with capsule delivery and absorption in the gut, although total caffeine absorption over time is not different. Rapid absorption may be important in many sporting situations. Caffeinated chewing gum improved endurance cycling performance, and there is limited evidence that repeated sprint cycling and power production may also be improved. Mouth rinsing with caffeine may stimulate nerves with direct links to the brain, in addition to caffeine absorption in the mouth. However, caffeine mouth rinsing has not been shown to have significant effects on cognitive performance. Delivering caffeine with mouth rinsing improved short-duration, high-intensity, repeated sprinting in normal and depleted glycogen states, while the majority of the literature indicates no ergogenic effect on aerobic exercise performance, and resistance exercise has not been adequately studied. Studies with caffeinated energy drinks have generally not examined the individual effects of caffeine on performance, making conclusions about this form of caffeine delivery impossible. Caffeinated aerosol mouth and nasal sprays may stimulate nerves with direct brain connections and enter the blood via mucosal and pulmonary absorption, although little support exists for caffeine delivered in this manner. Overall, more research is needed examining alternate forms of caffeine delivery including direct measures of brain activation and entry of caffeine into the blood, as well as more studies examining trained athletes and female subjects.
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Affiliation(s)
- Kate A Wickham
- Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Lawrence L Spriet
- Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.
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Richardson DL, Duncan MJ, Jimenez A, Jones VM, Juris PM, Clarke ND. The acute physiological effects of high- and low-velocity resistance exercise in older adults. Eur J Ageing 2018; 15:311-319. [PMID: 30310377 DOI: 10.1007/s10433-017-0439-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The aim of the present study was to determine if workload matched, high-velocity (HVE) and low-velocity (LVE) resistance exercise protocols, elicit differing acute physiological responses in older adults. Ten older adults completed three sets of eight exercises on six separate occasions (three HVE and three LVE sessions). Systolic blood pressure, diastolic blood pressure and blood lactate were measured pre- and post-exercise, heart rate was measured before exercise and following each set of each exercise. Finally, a rating of perceived exertion was measured following each set of each exercise. There were no significant differences in blood lactate (F(1,9) = 0.028; P = 0.872; η P 2 = 0.003), heart rate (F(1,9) = 0.045; P = 0.837; η P 2 = 0.005), systolic blood pressure (F(1,9) = 0.023; P = 0.884; η P 2 = 0.003) or diastolic blood pressure (F(1,9) = 1.516; P = 0.249; η P 2 = 0.144) between HVE and LVE. However, LVE elicited significantly greater ratings of perceived exertion compared to HVE (F(1,9) = 13.059; P = 0.006; η P 2 = 0.592). The present workload matched HVE and LVE protocols produced comparable physiological responses, although greater exertion was perceived during LVE.
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Affiliation(s)
- Darren L Richardson
- 1Centre for Applied Biological and Exercise Sciences, School of Life Sciences, Coventry University, Coventry, UK.,3Life Sciences, Faculty Health and Life Sciences, Coventry University, Priory Street, Coventry, CV1 5FB UK
| | - Michael J Duncan
- 1Centre for Applied Biological and Exercise Sciences, School of Life Sciences, Coventry University, Coventry, UK
| | - Alfonso Jimenez
- 1Centre for Applied Biological and Exercise Sciences, School of Life Sciences, Coventry University, Coventry, UK
| | - Victoria M Jones
- 1Centre for Applied Biological and Exercise Sciences, School of Life Sciences, Coventry University, Coventry, UK
| | - Paul M Juris
- 2Department of Kinesiology, University of Massachusetts Amherst, 30 Eastman Lane, Amherst, MA USA
| | - Neil D Clarke
- 1Centre for Applied Biological and Exercise Sciences, School of Life Sciences, Coventry University, Coventry, UK
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Acute Ingestion of Caffeinated Chewing Gum Improves Repeated Sprint Performance of Team Sport Athletes With Low Habitual Caffeine Consumption. Int J Sport Nutr Exerc Metab 2018; 28:221-227. [DOI: 10.1123/ijsnem.2017-0217] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The effects of acute ingestion of caffeine on short-duration high-intensity performance are equivocal, while studies of novel modes of delivery and the efficacy of low doses of caffeine are warranted. The aims of the present study were to investigate the effect of acute ingestion of caffeinated chewing gum on repeated sprint performance (RSP) in team sport athletes, and whether habitual caffeine consumption alters the ergogenic effect, if any, on RSP. A total of 18 male team sport athletes undertook four RSP trials using a 40-m maximum shuttle run test, which incorporates 10 × 40-m sprints with 30 s between the start of each sprint. Each participant completed two familiarization sessions, followed by caffeine (CAF; caffeinated chewing gum; 200 mg caffeine) and placebo (PLA; noncaffeinated chewing gum) trials in a randomized, double-blind manner. RSP, assessed by sprint performance decrement (%), did not differ (p = .209; effect size = 0.16; N = 18) between CAF (5.00 ± 2.84%) and PLA (5.43 ± 2.68%). Secondary analysis revealed that low habitual caffeine consumers (<40 mg/day, n = 10) experienced an attenuation of sprint performance decrement during CAF relative to PLA (5.53 ± 3.12% vs. 6.53 ± 2.91%, respectively; p = .049; effect size =0.33); an effect not observed in moderate/high habitual caffeine consumers (>130 mg/day, n = 6; 3.98 ± 2.57% vs. 3.80 ± 1.79%, respectively; p = .684; effect size = 0.08). The data suggest that a low dose of caffeine in the form of caffeinated chewing gum attenuates the sprint performance decrement during RSP by team sport athletes with low, but not moderate-to-high, habitual consumption of caffeine.
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Guzmán NAN, Molina DR, Núñez BF, Soto-Sosa JC, Abarca JEH. Bioequivalence and Pharmacokinetic Evaluation Study of Acetaminophen vs. Acetaminophen Plus Caffeine Tablets in Healthy Mexican Volunteers. Drugs R D 2018; 16:339-345. [PMID: 27734219 PMCID: PMC5114203 DOI: 10.1007/s40268-016-0145-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Objective The aim of this clinical trial was to establish the bioequivalence of two tablets containing acetaminophen 650 mg (reference) and acetaminophen 650 mg plus caffeine 65 mg (test), administered orally, in fasting conditions in healthy Mexican volunteers. Methods Blood samples were taken from 21 male and five female individuals, during a 24-h period, to characterize the pharmacokinetic profile of acetaminophen. Plasma samples were quantified by ultra-performance liquid chromatography, tandem mass spectrometry. Pharmacokinetic metrics (maximum plasma concentration, area under the curve from time zero to the last sampling time, and area under the curve from time zero to infinity) were used to determine the 90 % confidence interval of the test/reference coefficient. Results The geometric mean values for maximum plasma concentration obtained for the reference and test products were 9.46 ± 34.21 and 9.72 ± 32.38 µg/mL, respectively, whereas for the area under the curve from time zero to the last sampling time the values obtained were 34.93 ± 32.58 and 35.89 ± 31.03 µg h/mL for the reference and test formulations, respectively. The 90 % confidence intervals were within the acceptance range (80–125 %). Conclusions The test product was bioequivalent to the reference product. A faster absorption was seen in the test formulation in the Mexican population.
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Affiliation(s)
- Nora Angélica Núñez Guzmán
- Clínica de Enfermedades Crónicas y de Procedimientos Especiales, Fray Bernardino de Sahagún #101, Fraccionamiento Mirador del Punhuato, Morelia, Michoacán, Mexico.
| | - Daniel Ruiz Molina
- Clínica de Enfermedades Crónicas y de Procedimientos Especiales, Fray Bernardino de Sahagún #101, Fraccionamiento Mirador del Punhuato, Morelia, Michoacán, Mexico
| | - Benigno Figueroa Núñez
- Clínica de Enfermedades Crónicas y de Procedimientos Especiales, Fray Bernardino de Sahagún #101, Fraccionamiento Mirador del Punhuato, Morelia, Michoacán, Mexico
| | - Juan Carlos Soto-Sosa
- Clínica de Enfermedades Crónicas y de Procedimientos Especiales, Fray Bernardino de Sahagún #101, Fraccionamiento Mirador del Punhuato, Morelia, Michoacán, Mexico
| | - Jorge Eduardo Herrera Abarca
- Clínica de Enfermedades Crónicas y de Procedimientos Especiales, Fray Bernardino de Sahagún #101, Fraccionamiento Mirador del Punhuato, Morelia, Michoacán, Mexico
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Laizure SC, Meibohm B, Nelson K, Chen F, Hu Z, Parker RB. Comparison of caffeine disposition following administration by oral solution (energy drink) and inspired powder (AeroShot) in human subjects. Br J Clin Pharmacol 2017; 83:2687-2694. [PMID: 28758694 PMCID: PMC5698589 DOI: 10.1111/bcp.13389] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 07/26/2017] [Accepted: 07/26/2017] [Indexed: 12/18/2022] Open
Abstract
AIMS To determine the disposition and effects of caffeine after administration using a new dosage form (AeroShot) that delivers caffeine by inspiration of a fine powder into the oral cavity and compare it to an equivalent dose of an oral solution (energy drink) as the reference standard. METHODS Healthy human subjects (n = 17) inspired a 100 mg caffeine dose using the AeroShot device or consumed an energy drink on separate study days. Heart rate, blood pressure and subject assessments of effects were measured over an 8-h period. Plasma concentrations of caffeine and its major metabolites were determined by liquid chromatography-mass spectrometry. Pharmacokinetic, cardiovascular and perceived stimulant effects were compared between AeroShot and energy drink phases using a paired t test and standard bioequivalency analysis. RESULTS Caffeine disposition was similar after caffeine administration by the AeroShot device and energy drink: peak plasma concentration 1790 and 1939 ng ml-1 , and area under the concentration-time curve (AUC) 15 579 and 17 569 ng ml-1 × h, respectively, but they were not bioequivalent: AeroShot AUC of 80.3% (confidence interval 71.2-104.7%) and peak plasma concentration of 86.3% (confidence interval 62.8-102.8%) compared to the energy drink. Female subjects did have a significantly larger AUC compared to males after consumption of the energy drink. The heart rate and blood pressure were not significantly affected by the 100 mg caffeine dose, and there were no consistently perceived stimulant effects by the subjects using visual analogue scales. CONCLUSION Inspiration of caffeine as a fine powder using the AeroShot device produces a similar caffeine profile and effects compared to administration of an oral solution (energy drink).
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Affiliation(s)
- S. Casey Laizure
- Department of Clinical PharmacyUniversity of Tennessee Health Science CenterMemphisTennesseeUSA,
| | - Bernd Meibohm
- Department of Pharmaceutical SciencesUniversity of Tennessee Health Science CenterMemphisTennesseeUSA
| | - Kembral Nelson
- Department of Clinical PharmacyUniversity of Tennessee Health Science CenterMemphisTennesseeUSA,
| | - Feng Chen
- Department of Clinical PharmacyUniversity of Tennessee Health Science CenterMemphisTennesseeUSA,
| | - Zhe‐Yi Hu
- Department of Clinical PharmacyUniversity of Tennessee Health Science CenterMemphisTennesseeUSA,
| | - Robert B. Parker
- Department of Clinical PharmacyUniversity of Tennessee Health Science CenterMemphisTennesseeUSA,
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18
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Sadek P, Pan X, Shepherd P, Malandain E, Carney J, Coleman H. A Randomized, Two-Way Crossover Study to Evaluate the Pharmacokinetics of Caffeine Delivered Using Caffeinated Chewing Gum Versus a Marketed Caffeinated Beverage in Healthy Adult Volunteers. JOURNAL OF CAFFEINE RESEARCH 2017; 7:125-132. [PMID: 29230348 PMCID: PMC5724581 DOI: 10.1089/jcr.2017.0025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background: This study was conducted to compare the pharmacokinetics of caffeine delivered using caffeinated chewing gum to that delivered using a marketed caffeinated beverage (instant coffee) in 16 healthy adult volunteers. Materials and Methods: This was a controlled open-label, randomized, two-period crossover study. Caffeinated chewing gum and a serving of instant coffee, each containing ∼50 mg caffeine, were administered with blood samples collected before and up to 24 hours after administration starts. Plasma caffeine levels were analyzed using validated liquid chromatography coupled with tandem mass spectrometry methodology. Results: There were no statistical differences between the two caffeine products in tmax (p = 0.3308) and ka (p = 0.3894). Although formulated at ∼50 mg caffeine each, mean dose released from chewing gum was ∼18% less than beverage. Dose-normalized area under the concentration-time curve (AUC)0-t, AUC0-∞, and Cmax was similar between products. Although the criteria were not set a priori and the study was not powered for concluding bioequivalence, the 90% confidence intervals fell within the bioequivalence limit of 80% to 125%. Conclusions: Existing scientific literature on caffeine, based mostly on data from caffeinated beverages, can be leveraged to support the safety of caffeine delivered by chewing gum and current maximum safe caffeine dose advice should be applicable irrespective of delivery method.
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Affiliation(s)
- Paul Sadek
- Mars Wrigley Confectionery, Chicago, Illinois
| | - Xiao Pan
- Mars Wrigley Confectionery, Chicago, Illinois
| | | | | | | | - Hugh Coleman
- Covance Daytona Clinical Research Unit, Inc., Daytona Beach, Florida
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Wilhelmus MM, Hay JL, Zuiker RG, Okkerse P, Perdrieu C, Sauser J, Beaumont M, Schmitt J, van Gerven JM, Silber BY. Effects of a single, oral 60 mg caffeine dose on attention in healthy adult subjects. J Psychopharmacol 2017; 31:222-232. [PMID: 27649778 DOI: 10.1177/0269881116668593] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Caffeine induces positive effects on sustained attention, although studies assessing the acute effects of low caffeine dose (<75 mg) on sustained attention are limited and use short-term tests. Therefore, we investigated the acute effects of a 60 mg dose of caffeine on sustained attention in tests lasting up to 45 minutes using 82 low or non-caffeine-consuming healthy male ( n=41) and female ( n=41) adults aged between 40 and 60 years. Vigilance was measured using Mackworth Clock test, Rapid Visual Information Processing Test, adaptive tracking test, saccadic eye movement and attention switch test. Effects on mood and fatigue were analysed using Bond and Lader and Caffeine Research visual analogue scales, and Samn-Perelli questionnaire. Saliva sampling was performed for both compliance and caffeine pharmacokinetic analysis. Administration of a 60 mg caffeine dose resulted in a significant improvement in sustained attention compared with the placebo. Also a significantly improved peak saccadic velocity and reaction time performance was found, and decreased error rate. Significantly increased feelings of alertness, contentment and overall mood after caffeine treatment compared with placebo were observed. This study demonstrated that in healthy adult subjects oral administration of a single 60 mg caffeine dose elicited a clear enhancement of sustained attention and alertness, measured both in multiple objective performances and in subjective scales.
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Affiliation(s)
- Micha Mm Wilhelmus
- 1 Centre for Human Drug Research (CHDR), Leiden, the Netherlands.,3 Department of Anatomy and Neurosciences, VU University Medical Center, Amsterdam, the Netherlands
| | - Justin L Hay
- 1 Centre for Human Drug Research (CHDR), Leiden, the Netherlands
| | - Rob Gja Zuiker
- 1 Centre for Human Drug Research (CHDR), Leiden, the Netherlands
| | - Pieter Okkerse
- 1 Centre for Human Drug Research (CHDR), Leiden, the Netherlands
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Killgore WDS, Killgore DB, Ganesan G, Krugler AL, Kamimori GH. Trait-Anger Enhances Effects of Caffeine on Psychomotor Vigilance Performance. Percept Mot Skills 2016; 103:883-6. [PMID: 17326518 DOI: 10.2466/pms.103.3.883-886] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study examined the combined effects of caffeine and the personality attribute of trait-anger on the speed of psychomotor vigilance performance during sleep deprivation. 23 young adult soldiers (19 male) were administered the State-Trait Anger Expression Inventory–2 when well-rested. Participants were then sleep deprived for three consecutive nights (77 hours total) during which they completed repeated psychomotor vigilance testing. Half of the participants received four doses of oral caffeine (200 mg every 2 hr.; 800 mg total) each night, while the other half were administered a placebo. For the first night, higher scores on trait-anger, outward anger expression, and intensity of anger expression predicted better sustained overnight vigilance performance, but only for those volunteers receiving caffeine. These correlations were not significant for the subsequent nights. Findings suggest a possible synergistic effect between personality traits associated with arousal of the central nervous system and vigilance-promoting effects of caffeine.
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Affiliation(s)
- William D S Killgore
- Department of Behavioral Biology, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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21
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Richardson DL, Clarke ND. Effect of Coffee and Caffeine Ingestion on Resistance Exercise Performance. J Strength Cond Res 2016; 30:2892-900. [DOI: 10.1519/jsc.0000000000001382] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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Kamimori GH, McLellan TM, Tate CM, Voss DM, Niro P, Lieberman HR. Caffeine improves reaction time, vigilance and logical reasoning during extended periods with restricted opportunities for sleep. Psychopharmacology (Berl) 2015; 232:2031-42. [PMID: 25527035 PMCID: PMC4432086 DOI: 10.1007/s00213-014-3834-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 11/26/2014] [Indexed: 11/16/2022]
Abstract
RATIONALE Various occupational groups are required to maintain optimal physical and cognitive function during overnight periods of wakefulness, often with less than optimal sleep. Strategies are required to help mitigate the impairments in cognitive function to help sustain workplace safety and productivity. OBJECTIVES To test the effectiveness of repeated 200 mg doses of caffeine on cognitive function and live-fire marksmanship with soldiers during three successive nights of sustained wakefulness followed by 4-h afternoon sleep periods. METHODS Twenty Special Forces personnel (28.6 ± 4.7 years, 177.6 ± 7.5 cm and 81.2 ± 8.0 kg) were randomly assigned to receive four 200-mg doses of caffeine (n = 10) or placebo (n = 10) during the late evening and early morning hours during three successive days. An afternoon 4-h sleep period followed. The psychomotor (PVT) and field (FVT) vigilance, logical reasoning (LRT) tests and a vigilance monitor assessed cognitive function throughout the study. Live-fire marksmanship requiring friend-foe discrimination was assessed. RESULTS Caffeine maintained speed on the PVT (p < 0.02), improved detection of events during FVT (p < 0.001), increased number of correct responses to stimuli as assessed by the vigilance monitor (p < 0.001) and increased response speed during the LRT (p < 0.001) throughout the three overnight testing periods. Live-fire marksmanship was not altered by caffeine. CONCLUSIONS A total daily dose of 800 mg caffeine during successive overnight periods of wakefulness is an effective strategy to maintain cognitive function when optimal sleep periods during the day are not available.
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Affiliation(s)
- Gary H. Kamimori
- Behavioral Biology Branch, Center for Psychiatry and Neuroscience, Walter Reed Army Institute of Research, BLD 503, Silver Spring, MD 20910 USA
| | - Tom M. McLellan
- DRDC Toronto, 1133 Sheppard Avenue West, Toronto, ON M3M 3B9 Canada ,TM McLellan Research Inc., 25 Dorman Drive, Stouffville, ON L4A8A7 Canada
| | | | | | - Phil Niro
- Military Nutrition Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA 01760-5007 USA
| | - Harris R. Lieberman
- Military Nutrition Division, US Army Research Institute of Environmental Medicine (USARIEM), Natick, MA 01760-5007 USA
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Abstract
Caffeine is a popular work-enhancing supplement that has been actively researched since the 1970s. The majority of research has examined the effects of moderate to high caffeine doses (5-13 mg/kg body mass) on exercise and sport. These caffeine doses have profound effects on the responses to exercise at the whole-body level and are associated with variable results and some undesirable side effects. Low doses of caffeine (<3 mg/kg body mass, ~200 mg) are also ergogenic in some exercise and sport situations, although this has been less well studied. Lower caffeine doses (1) do not alter the peripheral whole-body responses to exercise; (2) improve vigilance, alertness, and mood and cognitive processes during and after exercise; and (3) are associated with few, if any, side effects. Therefore, the ergogenic effect of low caffeine doses appears to result from alterations in the central nervous system. However, several aspects of consuming low doses of caffeine remain unresolved and suffer from a paucity of research, including the potential effects on high-intensity sprint and burst activities. The responses to low doses of caffeine are also variable and athletes need to determine whether the ingestion of ~200 mg of caffeine before and/or during training and competitions is ergogenic on an individual basis.
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Affiliation(s)
- Lawrence L Spriet
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada,
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Ramakrishnan S, Laxminarayan S, Wesensten NJ, Kamimori GH, Balkin TJ, Reifman J. Dose-dependent model of caffeine effects on human vigilance during total sleep deprivation. J Theor Biol 2014; 358:11-24. [PMID: 24859426 DOI: 10.1016/j.jtbi.2014.05.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 03/11/2014] [Accepted: 05/08/2014] [Indexed: 12/11/2022]
Abstract
Caffeine is the most widely consumed stimulant to counter sleep-loss effects. While the pharmacokinetics of caffeine in the body is well-understood, its alertness-restoring effects are still not well characterized. In fact, mathematical models capable of predicting the effects of varying doses of caffeine on objective measures of vigilance are not available. In this paper, we describe a phenomenological model of the dose-dependent effects of caffeine on psychomotor vigilance task (PVT) performance of sleep-deprived subjects. We used the two-process model of sleep regulation to quantify performance during sleep loss in the absence of caffeine and a dose-dependent multiplier factor derived from the Hill equation to model the effects of single and repeated caffeine doses. We developed and validated the model fits and predictions on PVT lapse (number of reaction times exceeding 500 ms) data from two separate laboratory studies. At the population-average level, the model captured the effects of a range of caffeine doses (50-300 mg), yielding up to a 90% improvement over the two-process model. Individual-specific caffeine models, on average, predicted the effects up to 23% better than population-average caffeine models. The proposed model serves as a useful tool for predicting the dose-dependent effects of caffeine on the PVT performance of sleep-deprived subjects and, therefore, can be used for determining caffeine doses that optimize the timing and duration of peak performance.
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Affiliation(s)
- Sridhar Ramakrishnan
- DoD Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702, USA
| | - Srinivas Laxminarayan
- DoD Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702, USA
| | - Nancy J Wesensten
- Department of Behavioral Biology, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Gary H Kamimori
- Department of Behavioral Biology, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Thomas J Balkin
- Department of Behavioral Biology, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Jaques Reifman
- DoD Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, 504 Scott Street, Fort Detrick, MD 21702, USA.
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25
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Suh SY, Choi YS, Oh SC, Kim YS, Cho K, Bae WK, Lee JH, Seo AR, Ahn HY. Caffeine as an adjuvant therapy to opioids in cancer pain: a randomized, double-blind, placebo-controlled trial. J Pain Symptom Manage 2013; 46:474-82. [PMID: 23498965 DOI: 10.1016/j.jpainsymman.2012.10.232] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 10/18/2012] [Accepted: 10/23/2012] [Indexed: 10/27/2022]
Abstract
CONTEXT Opioid therapy often shows insufficient efficacy and substantial adverse events in patients with advanced cancer. OBJECTIVES To assess the efficacy of caffeine infusion as an adjuvant analgesic to opioid therapy in patients with advanced cancer. METHODS A double-blind, randomized, placebo-controlled trial was conducted in the palliative care wards of two teaching hospitals in South Korea. A total of 20 of 41 participants were assigned to the caffeine group and 21 to the placebo group. The participants received caffeine (200mg) or normal saline intravenously once a day for two days. The primary outcome was pain, which was measured using a 10-point rating scale. Other outcomes included drowsiness, confusion, nausea, sleep disturbance, fatigue, and sadness. RESULTS Three participants (two in the caffeine group and one in the placebo group) dropped out after the first intervention because of insomnia; thus, 38 participants completed the trial. Pain score was significantly lower in the caffeine group than in the placebo group after the second trial (P=0.038). The mean reduction in pain intensity in the caffeine group was 0.833 (95% confidence interval [CI] 0.601-1.066), whereas that in the placebo group was 0.350 (95% CI 0.168-0.532). Considering an improvement higher than 30% from baseline as the threshold value, drowsiness improved significantly in the caffeine group after the first trial (P=0.041). Adverse event rate did not differ between the two groups. CONCLUSION Caffeine infusion significantly reduced pain and drowsiness, but the reduction did not reach clinical significance in patients with advanced cancer undergoing opioid therapy. Further investigations are warranted.
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Affiliation(s)
- Sang-Yeon Suh
- Department of Medicine, Dongguk University, Seoul, Korea; Department of Family Medicine, Dongguk University Ilsan Hospital, Goyang-si, Gyeonggi-do, Korea.
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26
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Ryan EJ, Kim CH, Fickes EJ, Williamson M, Muller MD, Barkley JE, Gunstad J, Glickman EL. Caffeine gum and cycling performance: a timing study. J Strength Cond Res 2013; 27:259-64. [PMID: 22476164 DOI: 10.1519/jsc.0b013e3182541d03] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The purpose of this study was to determine the most efficacious time to administer caffeine (CAF) in chewing gum to enhance cycling performance. Eight male cyclists participated in 5 separate laboratory sessions. During the first visit, the subjects underwent a graded exercise test to determine maximal oxygen consumption (V[Combining Dot Above]O(2)max). During the next 4 visits, 3 pieces of chewing gum were administered at 3 time points (120-minute precycling, 60-minute precycling, and 5-minute precycling). In 3 of the 4 visits, at 1 of the time points mentioned previously, 300 mg of CAF was administered. During the fourth visit, placebo gum was administered at all 3 time points. The experimental trials were defined as follows: trial A (-120), trial B (-60), trial C (-5), and trial D (Placebo). After baseline measurements, time allotted for gum administration, and a standard warm-up, the participants cycled at 75% V[Combining Dot Above]O(2)max for 15 minutes then completed a 7-kJ·kg(-1) cycling time trial. Data were analyzed using a repeated measures analysis of variance. Cycling performance was improved in trial C (-5), but not in trial A (-120) or trial B (-60), relative to trial D (Placebo). CAF administered in chewing gum enhanced cycling performance when administered immediately prior, but not when administered 1 or 2 hours before cycling.
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Affiliation(s)
- Edward J Ryan
- Department of Exercise Physiology, Kent State University, Kent, OH, USA.
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Ramakrishnan S, Rajaraman S, Laxminarayan S, Wesensten NJ, Kamimori GH, Balkin TJ, Reifman J. A biomathematical model of the restoring effects of caffeine on cognitive performance during sleep deprivation. J Theor Biol 2013. [DOI: 10.1016/j.jtbi.2012.11.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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28
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Ryan EJ, Kim CH, Muller MD, Bellar DM, Barkley JE, Bliss MV, Jankowski-Wilkinson A, Russell M, Otterstetter R, Macander D, Glickman EL, Kamimori GH. Low-Dose Caffeine Administered in Chewing Gum Does Not Enhance Cycling to Exhaustion. J Strength Cond Res 2012; 26:844-50. [DOI: 10.1519/jsc.0b013e31822a5cd4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Heckman MA, Weil J, Gonzalez de Mejia E. Caffeine (1, 3, 7-trimethylxanthine) in foods: a comprehensive review on consumption, functionality, safety, and regulatory matters. J Food Sci 2010; 75:R77-87. [PMID: 20492310 DOI: 10.1111/j.1750-3841.2010.01561.x] [Citation(s) in RCA: 464] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Caffeine ranks as one of the top most commonly consumed dietary ingredients throughout the world. It is naturally found in coffee beans, cacao beans, kola nuts, guarana berries, and tea leaves including yerba mate. The total daily intake, as well as the major source of caffeine varies globally; however, coffee and tea are the 2 most prominent sources. Soft drinks are also a common source of caffeine as well as energy drinks, a category of functional beverages. Moderate caffeine consumption is considered safe and its use as a food ingredient has been approved, within certain limits, by numerous regulatory agencies around the world. Performance benefits attributed to caffeine include physical endurance, reduction of fatigue, and enhancing mental alertness and concentration. Caffeine has also been recently linked to weight loss and consequent reduction of the overall risks for developing the metabolic syndrome. However, the caloric contribution of caffeine-sweetened beverages needs to be considered in the overall energy balance. Despite all these benefits the potential negative effects of excessive caffeine intake should also be considered, particularly in children and pregnant women.
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Affiliation(s)
- Melanie A Heckman
- Dept. of Food Science and Human Nutrition, Univ. of Illinois Urbana-Champaign, IL, USA
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KILLGORE WILLIAMDS, KAMIMORI GARYH, BALKIN THOMASJ. Caffeine protects against increased risk-taking propensity during severe sleep deprivation. J Sleep Res 2010; 20:395-403. [DOI: 10.1111/j.1365-2869.2010.00893.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Benitez PL, Kamimori GH, Balkin TJ, Greene A, Johnson ML. Modeling fatigue over sleep deprivation, circadian rhythm, and caffeine with a minimal performance inhibitor model. Methods Enzymol 2009; 454:405-21. [PMID: 19216936 PMCID: PMC2654588 DOI: 10.1016/s0076-6879(08)03816-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Sleep loss, as well as concomitant fatigue and risk, is ubiquitous in today's fast-paced society. A biomathematical model that succeeds in describing performance during extended wakefulness would have practical utility in operational environments and could help elucidate the physiological basis of sleep loss effects. Eighteen subjects (14 males, 4 females; age 25.8 +/- 4.3 years) with low levels of habitual caffeine consumption (<300 mg/day) participated. On night 1, subjects slept for 8 h (2300-0700 h), followed by 77 h of continuous wakefulness. They were assigned randomly to receive placebo or caffeine (200 mg, i.e., two sticks of Stay Alert gum) at 0100, 0300, 0500, and 0700 during nights 2, 3, and 4. The psychomotor vigilance test (PVT) was administered periodically over the 77-h period of continuous wakefulness. Statistical analysis reveals lognormality in each PVT, allowing for closed-form median calculation. An iterative parameter estimation algorithm, which takes advantage of MatLab's (R2007a) least-squares nonlinear regression, is used to estimate model parameters from subjects' PVT medians over time awake. In the model, daily periodicity is accounted for with a four-component Fourier series, and a simplified binding function describes asymptotic fatigue. The model highlights patterns in data that suggest (1) the presence of a performance inhibitor that increases and saturates over the period of continuous wakefulness, (2) competitive inhibition of this inhibitor by caffeine, (3) the persistence of an internally driven circadian rhythm of alertness, and (4) a multiplicative relationship between circadian rhythm and performance inhibition. The present inhibitor-based minimal model describes performance data in a manner consistent with known biochemical processes.
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Affiliation(s)
- Patrick L Benitez
- Department of Pharmacology, University of Virginia Health System, Charlottesville, VA, USA
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Killgore WDS, Richards JM, Killgore DB, Kamimori GH, Balkin TJ. The trait of Introversion-Extraversion predicts vulnerability to sleep deprivation. J Sleep Res 2008; 16:354-63. [PMID: 18036080 DOI: 10.1111/j.1365-2869.2007.00611.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
According to Eysenck's theory of Introversion-Extroversion (I-E), introverts demonstrate higher levels of basal activity within the reticular-thalamic-cortical loop, yielding higher tonic cortical arousal than Extraverts, who are described conversely as chronically under-aroused and easily bored. We hypothesized that higher scores on the trait of Extraversion would be associated with greater declines in psychomotor vigilance performance during prolonged wakefulness. We evaluated the relationship between I-E and overnight psychomotor vigilance performance during 77 h of continuous sleep deprivation in a sample of 23 healthy adult military personnel (19 men; four women), ranging in age from 20 to 35 years. At baseline, volunteers completed the Revised NEO Personality Inventory (NEO PI-R) and completed psychomotor vigilance testing at approximately 10-min intervals from 00:15 to 08:50 hours over three nights of continuous sleep deprivation. In addition, 12 participants received four repeated administrations of caffeine (200 mg) every 2 h each night. Analysis of covariance and stepwise multiple regression analyses showed that, above and beyond the effects of caffeine, higher Extraversion was significantly related to more extensive declines in speed of responding and more frequent attentional lapses, but only for the first overnight testing session. Sub-factors of Extraversion, including Gregariousness and higher Activity level were most predictive of these changes following sleep loss. These findings are consistent with Eysenck's cortico-reticular activation theory of I-E and suggest that individual differences in the trait of Extraversion confer some vulnerability/resistance to the adverse effects of sleep loss on attention and vigilance.
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Affiliation(s)
- William D S Killgore
- Department of Behavioral Biology, Walter Reed Army Institute of Research, Silver Spring, MD, USA.
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James JE, Keane MA. Caffeine, sleep and wakefulness: implications of new understanding about withdrawal reversal. Hum Psychopharmacol 2007; 22:549-58. [PMID: 17868185 DOI: 10.1002/hup.881] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The broad aim of this review is to critically examine the implications of new understanding concerning caffeine withdrawal and withdrawal reversal in the context of research concerned with the effects of caffeine on sleep and wakefulness. A comprehensive search was conducted for relevant experimental studies in the PubMED and PsycINFO databases. Studies were assessed with particular reference to methodological adequacy for controlling against confounding due to caffeine withdrawal and withdrawal reversal. This assessment was used to clarify evidence of effects, highlight areas of ambiguity and derive recommendations for future research. It was found that researchers have generally failed to take account of the fact that habitual use of caffeine, even at moderate levels, leads to physical dependence evidenced by physiological, behavioural and subjective withdrawal effects during periods of abstinence. Consequently, there has been near-complete absence of adequate methodological controls against confounding due to reversal of withdrawal effects when caffeine is experimentally administered. The findings of what has been a substantial research effort to elucidate the effects of caffeine on sleep and wakefulness, undertaken over a period spanning decades, are ambiguous. Current shortcomings can be redressed by incorporating suitable controls in new experimental designs.
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Affiliation(s)
- Jack E James
- Department of Psychology, National University of Ireland, Galway, Ireland.
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Kahn-Greene ET, Lipizzi EL, Conrad AK, Kamimori GH, Killgore WD. Sleep deprivation adversely affects interpersonal responses to frustration. PERSONALITY AND INDIVIDUAL DIFFERENCES 2006. [DOI: 10.1016/j.paid.2006.06.002] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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KILLGORE WILLIAMDS. TRAIT-ANGER ENHANCES EFFECTS OF CAFFEINE ON PSYCHOMOTOR VIGILANCE PERFORMANCE. Percept Mot Skills 2006. [DOI: 10.2466/pms.103.7.883-886] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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