The Role of Caffeine in Enhancing Physical Performance: From Metabolism to Muscle Function

Introduction: Caffeine, a widely consumed stimulant, is recognized for its ability to block adenosine receptors, thereby enhancing alertness and possibly physical performance. Recent research examines caffeine's effectiveness in enhancing athletic performance, with numerous athletes supplementing with caffeine to gain a competitive edge. The aim of this study: This article examines the complex relationship between caffeine and the physical performance of athletes, including its effects on the central nervous system, metabolism, muscle function, and its application in a variety of sports, as well as potential gender differences and individual response variations. Materials and methods: This review was based on available data collected in the PubMed database and Google Scholar web search engine using the key words caffeine, athletic performance, physical performance Conclusions: Caffeine boosts muscle, cognitive, and metabolic function in volleyball and cycling. Caffeine boosts muscle contractility, endurance, and focus, but details matter. Caffeine effects and sports outcomes vary by gender, emphasizing the need for individualized supplementation. Dosage, timing, and physiological conditions affect results, research shows. Caffeine boosts performance, but athletes, coaches, and practitioners should be careful. To maximize caffeine's benefits and minimize side effects, athletes must be treated individually and by sport

Patients with alopecia areata are at risk of endothelial dysfunction: results of a case–control study

Background: Alopecia areata (AA) is an autoimmune form of hair loss, which may affect any hair-bearing area. It has been suggested that AA is associated with an increased risk of metabolic and cardiovascular comorbidities. Aim: To evaluate the early predictors of cardiovascular disease [endothelial function (EF) and arterial stiffness (AS)] in patients with AA without prior cardiovascular disease, and compare with healthy controls (HCs). Methods: In total, 52 patients with AA (38 women and 14 men; mean age 41 years, range 30–52 years) and 34 HCs, matched for age, sex and body mass index, were enrolled in the study. EF, expressed as reactive hyperaemia index (RHI), and AS, identified by augmentation index at 75 beats/min (AI@75) were assessed with the use of the Endo-PAT 2000 device. Endothelial dysfunction (ED) was defined as RHI value ≤1.67. Results: ED was observed in 22 of 52 patients with AA (42%) and in 4 of 34 HCs (12%) (P < 0.01). Moreover, mean RHI was lower in patients with AA compared with HCs (1.90 ± 0.31 vs. 2.11 ± 0.45; P = 0.03). There was no significant difference in AI@75 between patients with AA and HCs. Conclusions: Patients with AA show abnormalities in early predictors of cardiovascular diseases. Regular cardiovascular screening might be appropriate for patients with AA