Common questions and misconceptions about caffeine supplementation: what does the scientific evidence really show?

Caffeine is a popular ergogenic aid that has a plethora of evidence highlighting its positive effects. A Google Scholar search using the keywords "caffeine" and "exercise" yields over 200,000 results, emphasizing the extensive research on this topic. However, despite the vast amount of available data, it is intriguing that uncertainties persist regarding the effectiveness and safety of caffeine. These include but are not limited to: 1. Does caffeine dehydrate you at rest? 2. Does caffeine dehydrate you during exercise? 3. Does caffeine promote the loss of body fat? 4. Does habitual caffeine consumption influence the performance response to acute caffeine supplementation? 5. Does caffeine affect upper vs. lower body performance/strength differently? 6. Is there a relationship between caffeine and depression? 7. Can too much caffeine kill you? 8. Are there sex differences regarding caffeine's effects? 9. Does caffeine work for everyone? 10. Does caffeine cause heart problems? 11. Does caffeine promote the loss of bone mineral? 12. Should pregnant women avoid caffeine? 13. Is caffeine addictive? 14. Does waiting 1.5-2.0 hours after waking to consume caffeine help you avoid the afternoon "crash?" To answer these questions, we performed an evidence-based scientific evaluation of the literature regarding caffeine supplementation.

International society of sports nutrition position stand: coffee and sports performance.

Based on review and critical analysis of the literature regarding the contents and physiological effects of coffee related to physical and cognitive performance conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society:(1) Coffee is a complex matrix of hundreds of compounds. These are consumed with broad variability based upon serving size, bean type (e.g. common Arabica vs. Robusta), and brew method (water temperature, roasting method, grind size, time, and equipment).(2) Coffee's constituents, including but not limited to caffeine, have neuromuscular, antioxidant, endocrine, cognitive, and metabolic (e.g. glucose disposal and vasodilation) effects that impact exercise performance and recovery.(3) Coffee's physiologic effects are influenced by dose, timing, habituation to a small degree (to coffee or caffeine), nutrigenetics, and potentially by gut microbiota differences, sex, and training status.(4) Coffee and/or its components improve performance across a temporal range of activities from reaction time, through brief power exercises, and into the aerobic time frame in most but not all studies. These broad and varied effects have been demonstrated in men (mostly) and in women, with effects that can differ from caffeine ingestion, per se. More research is needed.(5) Optimal dosing and timing are approximately two to four cups (approximately 473-946 ml or 16-32 oz.) of typical hot-brewed or reconstituted instant coffee (depending on individual sensitivity and body size), providing a caffeine equivalent of 3-6 mg/kg (among other components such as chlorogenic acids at approximately 100-400 mg per cup) 60 min prior to exercise.(6) Coffee has a history of controversy regarding side effects but is generally considered safe and beneficial for healthy, exercising individuals in the dose range above.(7) Coffee can serve as a vehicle for other dietary supplements, and it can interact with nutrients in other foods.(8) A dearth of literature exists examining coffee-specific ergogenic and recovery effects, as well as variability in the operational definition of "coffee," making conclusions more challenging than when examining caffeine in its many other forms of delivery (capsules, energy drinks, "pre-workout" powders, gum, etc.).

Reasons for delay in timely administration of adjuvant chemotherapy for patients with stage III colon cancer: a multicentre cohort study from the McGill University Department of Oncology.

PURPOSE: Adjuvant chemotherapy within 56 or 84 days following curative resection is globally accepted as the standard of care for stage III colon cancer as it has been associated with improved overall survival. Initiation of adjuvant chemotherapy within this time frame is therefore recommended by clinical practice guidelines, including the European Society for Medical Oncology. The objective of this study was to evaluate adherence to these clinical practice guidelines for patients with stage III colon cancer across the Rossy Cancer Network (RCN); a partnership of McGill University's Faculty of Medicine, McGill University Health Centre, Jewish General Hospital and St Mary's Hospital Center. PATIENTS AND METHODS: 187 patients who had been diagnosed with stage III colon cancer and received adjuvant chemotherapy within the RCN partner hospitals from 2012 to 2015 were included. Patient and treatment information was retrospectively determined by chart review. Χ2 and Wilcoxon rank-sum tests were used to measure associations and a multivariate Cox regression model was used to determine risk factors contributing to delays in administration of adjuvant chemotherapy. RESULTS: The median turnaround time between surgery and adjuvant chemotherapy was 69 days. Importantly, only 27% of patients met the 56-day target, and 71% met the 84-day target. Increasing age, having more than one surgical complication and being diagnosed between 2013-2014 and 2014-2015 reduced the likelihood that patients met these targets. Furthermore, delays were observed at most intervals from surgery to first adjuvant chemotherapy treatment. CONCLUSION: Our study found that within these academic hospital settings, 27% of patients met the 56-day target, and 71% met the 84-day target. Delays were associated with hospital, surgeon and patient-related factors. Initiatives in quality improvement are needed in order to improve adherence to recommended treatment guidelines for prompt administration of adjuvant chemotherapy for stage III colon cancer.

Real and Perceived Effects of Caffeine on Sprint Cycling in Experienced Cyclists.

Anderson, DE, German, RE, Harrison, ME, Bourassa, KN, and Taylor, CE. Real and perceived effects of caffeine on sprint cycling in experienced cyclists. J Strength Cond Res 34(4): 929-933, 2020-Caffeine ingestion before an exercise bout may provide ergogenic effects on anaerobic performance, particularly in trained athletes. However, the degree of influence of caffeine may be coupled with the placebo effect. A double-blind, placebo-controlled, randomized design was used to determine the real and perceived effects of caffeine on anaerobic performance. Ten competitively trained cyclists (9 men and 1 woman) completed 3 trials of the Wingate Anaerobic Test (WAnT). Subjects were given coffee that they believed contained a high caffeine dose, a low caffeine dose, or a placebo 45 minutes before WAnT. Subjects were actually given 2 placebos (decaffeinated coffee) and one dose of caffeine (280 mg). Level of significance was p ≤ 0.05. No significant differences were found between trials for blood lactate concentration and heart rate. Seven of the subjects (70%) correctly identified the caffeine trial as the high caffeine trial. Time to peak power was significantly shorter for the trial in which subjects incorrectly guessed they had consumed caffeine when given the placebo compared with placebo trial (1.6 ± 0.1 vs. 2.3 ± 0.2 seconds). Power drop was significantly higher for the trial in which subjects incorrectly guessed they had consumed caffeine when given the placebo compared with placebo trial (524 ± 37 vs. 433 ± 35 W). There seems to be a placebo effect of caffeine on anaerobic performance. Improved performance may result from psychological advantages rather than physical advantages. Coaches may find it beneficial to use a placebo to improve anaerobic performance, especially if concerned about the side effects or cost of caffeine.

Effect of Caffeine on Sprint Cycling in Experienced Cyclists.

Anderson, DE, LeGrand, SE, and McCart, RD. Effect of caffeine on sprint cycling in experienced cyclists. J Strength Cond Res 32(8): 2221-2226, 2018-Research regarding the ergogenic effects of caffeine (CAF) in anaerobic activity remains inconclusive. However, some researchers have found significant improvements in anaerobic performance when testing specifically trained athletes. A double-blind, placebo-controlled, counterbalanced, cross-over design was implemented to assess the impact of CAF on a 30-second Wingate Anaerobic Test (WAnT) in experienced cyclists. Nine experienced cyclists volunteered to participate in this study (men, n = 7 and women, n = 2). The subjects completed 2 separate experimental trials consisting of a 30-second WAnT at a resistance of 9% body mass. In a random order, 1 hour before each WAnT, subjects ingested either a CAF (∼280 mg) or placebo (PLAC) coffee. For each trial, heart rate (HR) and blood lactate (BL) values were recorded at rest, pre-WAnT, post-WAnT, and 5 minutes post-WAnT. After each trial, the subjects recorded their perception of which treatment they received. Heart rate and BL responses were not significantly different between the CAF and PLAC conditions. The ingestion of CAF did not significantly improve peak anaerobic power, mean anaerobic power, nor fatigue index. In at least 1 of the 2 trials, 44% of the subjects incorrectly guessed which substance they had ingested. The findings of this study do not show a significant correlation between CAF ingestion and improved anaerobic performance in experienced cyclists. However, performance enhancements may depend on varying individual responses to CAF. Athletes who are positive CAF responders may consider using coffee before competition to improve anaerobic performance.

An approach to pneumatosis intestinalis: Factors affecting your management.

Pneumatosis Intestinalis (PI) is defined as the presence of extra-luminal gas confined to the bowel wall. PI is an ominous condition often requiring emergent surgery. The management can be challenging in some circumstances, as the choice of surgery versus medical treatment can be difficult. In this study, we first report the case of a seventy-seven year old woman presenting to the emergency department with the presence of PI on computed tomography of the abdomen. Secondly, we review the existing literature regarding the management of PI and we suggest a treatment algorithm based on clinical, laboratory and radiological findings.

The impact of feedback on dietary intake and body composition of college women volleyball players over a competitive season.

The purpose of this study was to examine the impact of nutritional feedback on dietary intake and body composition of college women volleyball players. Eight members of an National Collegiate Athletic Association (NCAA) division II women's volleyball team participated as subjects. Three-day diet records and body composition (via air displacement plethysmography) were analyzed at the beginning of the season (Beginning), peak training during the season (Peak), and 1 week postseason (After). During the first season (Baseline), the athletes were given no information concerning their dietary intakes. In the following year (Feedback), athletes were given information with regard to dietary intakes of themselves and the team as a whole. Percent body fat was not significantly different between Baseline and Feedback trials. During Beginning and Peak, the mean energy intakes ranged from 35.3 to 40.8 kcal.kg.bw. Protein intake was significantly greater in Feedback-Beginning (1.5 +/- 0.9 gxkgxbw) compared to Baseline-Beginning (1.1 +/- 0.1 gxkgxbw). No significant differences were seen in Baseline vs. Feedback for either carbohydrate or fat intakes. The only vitamin with significantly different consumption was vitamin C, with intakes of Feedback-Beginning (303.8 +/- 99.8% Dietary Reference Intakes [DRI]) vs. Baseline-Beginning (115.3 +/- 32.3% DRI). A significantly greater amount of calcium was consumed at Feedback-Beginning (152.0 +/- 25.2% DRI) compared to Baseline-Beginning (102.2 +/- 21.2% DRI). In conclusion, dietary feedback resulted in increased intake of protein, vitamin C, and calcium at the beginning of the season only for female collegiate volleyball players. Other than an increase in fiber, dietary intake at the peak of the season and postseason was not influenced by feedback. Body composition was unaffected by feedback at Beginning, Peak, and After.

The nursing strategy officer: a new and evolving role.

As health systems have become more expansive, strategic and operational planning processes have become more complex. Enterprise-wide strategic plans now address a broad set of considerations that have significant impact across the organization, particularly nursing and patient care programs. Synchronous implementation of organizational strategies can be very challenging. Organizational capacity is constantly challenged with competing agendas. To drive the successful implementation of organization-wide strategies and optimize success, Cleveland Clinic Foundation established a new role modeled after other industry sectors, the Associate Chief Nurse for Strategic Planning. This article describes the genesis and focus of this new, important role.

Fluid resuscitation therapy for hemorrhagic shock.

Hemorrhagic shock is a severe life-threatening emergency affecting all organ systems of the body by depriving tissue of sufficient oxygen and nutrients by decreasing cardiac output. This article is a short review of the different types of shock, followed by information specifically referring to hemorrhagic shock. The American College of Surgeons categorized shock into 4 classes: (1) distributive; (2) obstructive; (3) cardiogenic; and (4) hemorrhagic. Similarly, the classes of hemorrhagic shock are grouped by signs and symptoms, amount of blood loss, and the type of fluid replacement. This updated review is helpful to trauma nurses in understanding the various clinical aspects of shock and the current recommendations for fluid resuscitation therapy following hemorrhagic shock.

Reliability of air displacement plethysmography.

The purpose of this study was to examine the reliability of an air displacement plethysmography device (BOD POD) over trials performed on 3 different days. Subjects consisted of 24 healthy adults (8 men, 16 women), ages 18-38 years, with body weights 46.8-93.6 kg, body mass indexes of 19.1-30.1 kg x m(-2), and percentage body fats (BF) of 7.9-43.1%. Two estimates of BF were performed on 3 days. Paired t-tests revealed no significant within-day differences in body volume (BV), thoracic gas volume (V(TG)), body density (BD), and BF. Correlations between the two V(TG) measures on a day were r = 0.86 for day 1, r = 0.93 for day 2, and r = 0.96 for day 3. BF estimates within a day had high correlations of r = 0.98. Significant differences were found between days for measures of BV, V(TG), BD, and BF. These results indicate a high reliability for within-day estimates of BF and significant differences in between-day estimates of BF using air displacement plethysmography. Reliability of BF may be increased by requiring subjects to practice the procedure for V(TG) measurement.

The new health care paradigm: roles and competencies of leaders in the service line management approach.

PURPOSE: The purpose of this paper is to discuss the need for the service line management approach in health care. Service line management is increasingly utilized by US health care organizations as an innovative method for providing the needed stimulus to increase viability and profitability for the ailing health care sector. DESIGN/METHODOLOGY/APPROACH: Using current literature, this study describes a paradigm shift from traditional health care management approaches to focus on the importance of a service line management approach with its specific emphasis on competencies of leaders. RESEARCH LIMITATIONS/IMPLICATIONS: Four essential competencies--conceptual, participation, interpersonal, and leadership--must be gained by leaders to bring about organizational growth. PRACTICAL IMPLICATIONS: Health care managers must understand and practice these four key competencies to become effective health care leaders. ORIGINALITY/VALUE: This paper provides useful information on the need for the service line management approach in health care.

Center for Integrated Health Care: primary and mental health care for people with severe and persistent mental illnesses.

The Center for Integrated Health Care capitalizes on the abilities, drive, and autonomy of advanced practice nurses, resulting in an exciting, timely academic nursing center exemplar. People with severe and persistent mental illnesses receive care that is targeted specifically to a population with chronic mental illnesses and tailored to the unique individual by integrating primary and mental health care. This Center is a partnership between Thresholds, a psychosocial rehabilitation center, staff and University of Illinois at Chicago, College of Nursing faculty. The Center's goals are to provide quality care, support teaching and learning for nursing and other health professional learners, and generate new knowledge related to the integration of mental and physical health care. To achieve long-term sustainability, the Center must partner with a federally qualified health center.