{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T06:17:57Z","timestamp":1791613077082,"version":"4.3.4"},"reference-count":43,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,21]],"date-time":"2022-11-21T00:00:00Z","timestamp":1668988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002322","name":"Coordination for Higher Education Staff Development","doi-asserted-by":"publisher","award":["88882.181208\/2018-01"],"award-info":[{"award-number":["88882.181208\/2018-01"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>The effects of acute caffeine supplementation on muscular strength remain unclear. We examined the effects of two different doses of caffeine on muscle strength and calcium in plasma compared to placebo using a crossover, randomized, double-blind, placebo-controlled design. Twenty-one (n = 21) recreationally resistance-trained participants were randomly assigned into three experimental conditions: 6 mg\u00b7kg bw\u22121 of caffeine (CF6); 8 mg\u00b7kg bw\u22121 of caffeine (CF8); or placebo (PLA), with a 7-day washout period between conditions. Muscular strength assessments were made for both upper (bench press) and lower body muscles (squat and deadlift). Calcium release in plasma was measured on five different occasions. Bench press (CF8: 100.1 \u00b1 1.9 kg; PLA: 94.2 \u00b1 2.5 kg), deadlift (CF8: 132.8 \u00b1 3.5 kg; PLA: 120.7 \u00b1 5.7 kg), and squat (CF8: 130.1 \u00b1 4.9 kg; PLA 119.4 \u00b1 5.4 kg) strength were all significantly (p &lt; 0.001) improved in CF8 compared to PLA. Calcium release in plasma was significantly increased in CF8, whereas no changes were observed in CF6 or PLA. Overall, 8 mg\u00b7kg bw\u22121 of caffeine appears to be an effective dose to optimize upper and lower body muscular strength and calcium release in recreationally trained participants.<\/jats:p>","DOI":"10.3390\/nu14224921","type":"journal-article","created":{"date-parts":[[2022,11,21]],"date-time":"2022-11-21T04:13:36Z","timestamp":1669004016000},"page":"4921","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["High Doses of Caffeine Increase Muscle Strength and Calcium Release in the Plasma of Recreationally Trained Men"],"prefix":"10.3390","volume":"14","author":[{"given":"Luis","family":"Ferreira","sequence":"first","affiliation":[{"name":"Metabolism, Nutrition and Strength Training Research Group (GPMENUTF), Federal University of Paran\u00e1 (UFPR), Curitiba 81531-980, PR, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6896-5552","authenticated-orcid":false,"given":"Scott","family":"Forbes","sequence":"additional","affiliation":[{"name":"Department of Physical Education Studies, Brandon University, Brandon, MB R7A 6A9, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3565-8331","authenticated-orcid":false,"given":"Marcelo","family":"Barros","sequence":"additional","affiliation":[{"name":"Institute of Physical Activity Sciences and Sports, Universidade Cruzeiro do Sul, S\u00e3o Paulo 07115-000, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9","family":"Smolarek","sequence":"additional","affiliation":[{"name":"Metabolism, Nutrition and Strength Training Research Group (GPMENUTF), Federal University of Paran\u00e1 (UFPR), Curitiba 81531-980, PR, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8848-7946","authenticated-orcid":false,"given":"Alysson","family":"Enes","sequence":"additional","affiliation":[{"name":"Metabolism, Nutrition and Strength Training Research Group (GPMENUTF), Federal University of Paran\u00e1 (UFPR), Curitiba 81531-980, PR, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2128-1182","authenticated-orcid":false,"given":"Antonio","family":"Lancha-Junior","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Investigation: Experimental Surgery (LIM 26), Clinic\u2019s Hospital of Medical School, University of Sao Paulo, Sao Paulo 05508-030, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0008-7989","authenticated-orcid":false,"given":"Gabriel","family":"Martins","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Investigation: Experimental Surgery (LIM 26), Clinic\u2019s Hospital of Medical School, University of Sao Paulo, Sao Paulo 05508-030, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tacito","family":"Souza-Junior","sequence":"additional","affiliation":[{"name":"Metabolism, Nutrition and Strength Training Research Group (GPMENUTF), Federal University of Paran\u00e1 (UFPR), Curitiba 81531-980, PR, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1152\/japplphysiol.00570.2014","article-title":"Caffeine Consumption around an Exercise Bout: Effects on Energy Expenditure, Energy Intake, and Exercise Enjoyment","volume":"117","author":"Schubert","year":"2014","journal-title":"J. Appl. Physiol."},{"key":"ref_2","first-page":"144","article-title":"A Cafe\u00edna Potencializa O Desempenho Em Atividades De Endurance?","volume":"6","author":"Capitani","year":"2012","journal-title":"Braz. J. Biomotricity"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1016\/j.neubiorev.2016.09.001","article-title":"A Review of Caffeine\u2019s Effects on Cognitive, Physical and Occupational Performance","volume":"71","author":"McLellan","year":"2016","journal-title":"Neurosci. Biobehav. Rev."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1311","DOI":"10.1139\/H08-129","article-title":"Does Caffeine Alter Muscle Carbohydrate and Fat Metabolism during Exercise?","volume":"33","author":"Graham","year":"2008","journal-title":"Appl. Physiol. Nutr. Metab."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1519\/JSC.0b013e3181c1f88a","article-title":"Efficacy of acute caffeine ingestion for short-term high-intensity exercise performance: A systematic review","volume":"24","author":"Astorino","year":"2010","journal-title":"J. Strength Cond. Res."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"599","DOI":"10.1113\/jphysiol.1990.sp018120","article-title":"Effects of caffeine on calcium release from the sarcoplasmic reticulum in frog skeletal muscle fibres","volume":"425","author":"Klein","year":"1990","journal-title":"J. Physiol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"296","DOI":"10.1152\/japplphysiol.00908.2007","article-title":"Impaired Calcium Release during Fatigue","volume":"104","author":"Allen","year":"2008","journal-title":"J. Appl. Physiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1056","DOI":"10.1152\/japplphysiol.00937.2004","article-title":"Caffeine Increases Time to Fatigue by Maintaining Force and Not by Altering Firing Rates during Submaximal Isometric Contractions","volume":"99","author":"Meyers","year":"2005","journal-title":"J. Appl. Physiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1719","DOI":"10.1152\/jappl.2000.89.5.1719","article-title":"Caffeine Potentiates Low Frequency Skeletal Muscle Force in Habitual and Nonhabitual Caffeine Consumers","volume":"89","author":"Tarnopolsky","year":"2000","journal-title":"J. Appl. Physiol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2153","DOI":"10.1007\/s00018-007-7051-9","article-title":"Caffeine Analogs: Biomedical Impact","volume":"64","author":"Daly","year":"2007","journal-title":"Cell. Mol. Life Sci."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1016\/0143-4160(86)90038-2","article-title":"Intracellular Calcium and Smooth Muscle Contraction","volume":"7","author":"Sommerville","year":"1986","journal-title":"Cell Calcium"},{"key":"ref_12","first-page":"506","article-title":"The Acute Effects of a Caffeine-Containing Supplement on Strength, Muscular Endurance, and Anaerobic Capabilities","volume":"20","author":"Beck","year":"2006","journal-title":"J. Strength Cond. Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"702","DOI":"10.1080\/17461391.2015.1085097","article-title":"Effects of Coffee and Caffeine Anhydrous on Strength and Sprint Performance","volume":"16","author":"Trexler","year":"2016","journal-title":"Eur. J. Sport Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2205","DOI":"10.1249\/MSS.0b013e3181e3a11d","article-title":"Effect of Two Doses of Caffeine on Muscular Function during Isokinetic Exercise","volume":"42","author":"Astorino","year":"2010","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1024","DOI":"10.1016\/j.jsams.2017.03.017","article-title":"Effect of a Moderate Caffeine Dose on Endurance Cycle Performance and Thermoregulation during Prolonged Exercise in the Heat","volume":"20","author":"Beaumont","year":"2017","journal-title":"J. Sci. Med. Sport"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1519\/JSC.0000000000000625","article-title":"Acute effects of caffeine on strength and muscle activation of the elbow flexors","volume":"29","author":"Trevino","year":"2015","journal-title":"J. Strength Cond. Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1007\/s00421-007-0557-x","article-title":"Effect of Caffeine Ingestion on One-Repetition Maximum Muscular Strength","volume":"102","author":"Astorino","year":"2008","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1186\/1550-2783-7-18","article-title":"Caffeine Enhances Upper Body Strength in Resistance-Trained Women","volume":"7","author":"Goldstein","year":"2010","journal-title":"J. Int. Soc. Sports Nutr."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"681","DOI":"10.1136\/bjsports-2018-100278","article-title":"Wake up and Smell the Coffee: Caffeine Supplementation and Exercise Performance\u2014An Umbrella Review of 21 Published Meta-Analyses","volume":"54","author":"Grgic","year":"2020","journal-title":"Br. J. Sports Med."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.jss.2008.04.019","article-title":"Bioimpedance Analysis: A Guide to Simple Design and Implementation","volume":"153","author":"Aroom","year":"2009","journal-title":"J. Surg. Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1249\/01.MSS.0000048831.15016.2A","article-title":"Concurrent Validation of the OMNI Perceived Exertion Scale for Resistance Exercise","volume":"35","author":"Robertson","year":"2003","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1111\/j.1750-3841.2010.01561.x","article-title":"Caffeine (1, 3, 7-Trimethylxanthine) in Foods: A Comprehensive Review on Consumption, Functionality, Safety, and Regulatory Matters","volume":"75","author":"Heckman","year":"2010","journal-title":"J. Food Sci."},{"key":"ref_23","first-page":"918","article-title":"Determining the magnitude of treatment effects in strength training research through the use of the effect size","volume":"18","author":"Rhea","year":"2004","journal-title":"J. Strength Cond. Res."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2926","DOI":"10.1519\/JSC.0000000000000945","article-title":"Carbohydrate and caffeine mouth rinses do not affect maximum strength and muscular endurance performance","volume":"29","author":"Clarke","year":"2015","journal-title":"J. Strength Cond. Res."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1186\/s12970-016-0157-4","article-title":"The Influence of Caffeine Ingestion on Strength and Power Performance in Female Team-Sport Players","volume":"13","author":"Ali","year":"2016","journal-title":"J. Int. Soc. Sports Nutr."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"10209","DOI":"10.1038\/srep10209","article-title":"Caffeine-Induced Increase in Voluntary Activation and Strength of the Quadriceps Muscle during Isometric, Concentric and Eccentric Contractions","volume":"5","author":"Behrens","year":"2015","journal-title":"Sci. Rep."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3239","DOI":"10.1519\/JSC.0000000000000447","article-title":"Effect of Caffeine Ingestion on Maximal Voluntary Contraction Strength in Upper- and Lower-Body Muscle Groups","volume":"28","author":"Timmins","year":"2014","journal-title":"J. Strength Cond. Res."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Wilk, M., Krzysztofik, M., Filip, A., Zajac, A., and Del Coso, J. (2019). The Effects of High Doses of Caffeine on Maximal Strength and Muscular Endurance in Athletes Habituated to Caffeine. Nutrients, 11.","DOI":"10.3390\/nu11081912"},{"key":"ref_29","first-page":"475","article-title":"RBCDH Methods for Estimating Body Weight and Height in Hospitalized Adults: A comparative analysis","volume":"16","author":"Paula","year":"2014","journal-title":"Rev. Bras. De Cineantropometria Desempenho Hum."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1007\/s40279-018-0997-y","article-title":"The Influence of Caffeine Supplementation on Resistance Exercise: A Review","volume":"49","author":"Grgic","year":"2019","journal-title":"Sport. Med."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1136\/bjsports-2018-099027","article-title":"IOC Consensus Statement: Dietary Supplements and the High-Performance Athlete","volume":"52","author":"Maughan","year":"2018","journal-title":"Br. J. Sports Med."},{"key":"ref_32","first-page":"574854","article-title":"Caffeine and Exercise Performance: Possible Directions for Definitive Findings","volume":"117","author":"Martins","year":"2021","journal-title":"Front. Sport. Act. Living"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"813","DOI":"10.2165\/11317770-000000000-00000","article-title":"Caffeine and Anaerobic Performance","volume":"39","author":"Davis","year":"2009","journal-title":"Sport. Med."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1016\/j.jsams.2018.08.016","article-title":"The Effects of Caffeine Ingestion on Isokinetic Muscular Strength: A Meta-Analysis","volume":"22","author":"Grgic","year":"2019","journal-title":"J. Sci. Med. Sport"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1227","DOI":"10.1152\/japplphysiol.00187.2002","article-title":"Exercise Endurance 1, 3, and 6 h after Caffeine Ingestion in Caffeine Users and Nonusers","volume":"93","author":"Bell","year":"2002","journal-title":"J. Appl. Physiol."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Lara, B., Ruiz-Moreno, C., Salinero, J.J., and Del Coso, J. (2019). Time Course of Tolerance to the Performance Benefits of Caffeine. PLoS ONE, 14.","DOI":"10.1371\/journal.pone.0210275"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1159\/000322696","article-title":"Caffeine and Creatine Use in Sport","volume":"57","author":"Tarnopolsky","year":"2011","journal-title":"Ann. Nutr. Metab."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1519\/JSC.0000000000003383","article-title":"Early Signs of Inflammation with Mild Oxidative Stress in Mixed Martial Arts Athletes after Simulated Combat","volume":"36","author":"Lambertucci","year":"2022","journal-title":"J. Strength Cond. Res."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"271","DOI":"10.5604\/20831862.1120934","article-title":"Delayed Uric Acid Accumulation in Plasma Provides Additional Anti-Oxidant Protection against Iron-Triggered Oxidative Stress after a Wingate Test","volume":"31","author":"Ganini","year":"2014","journal-title":"Biol. Sport"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/BF00925956","article-title":"Calcium and Smooth Muscle Contraction","volume":"135","author":"Jiang","year":"1994","journal-title":"Mol. Cell. Biochem."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"845","DOI":"10.1016\/0306-4522(93)90029-F","article-title":"Caffeine-Induced Calcium Release from Internal Stores in Cultured Rat Sensory Neurons","volume":"57","author":"Usachev","year":"1993","journal-title":"Neuroscience"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"399","DOI":"10.1152\/ajpregu.00386.2002","article-title":"Central Nervous System Effects of Caffeine and Adenosine on Fatigue","volume":"284","author":"Davis","year":"2003","journal-title":"Am. J. Physiol. -Regul. Integr. Comp. Physiol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1215","DOI":"10.1152\/physrev.2000.80.3.1215","article-title":"Calcium Ion in Skeletal Muscle: Its Crucial Role for Muscle Function, Plasticity, and Disease","volume":"80","author":"Berchtold","year":"2000","journal-title":"Physiol. Rev."}],"container-title":["Nutrients"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6643\/14\/22\/4921\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:22:32Z","timestamp":1760145752000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6643\/14\/22\/4921"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,11,21]]},"references-count":43,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2022,11]]}},"alternative-id":["nu14224921"],"URL":"https:\/\/doi.org\/10.3390\/nu14224921","relation":{},"ISSN":["2072-6643"],"issn-type":[{"value":"2072-6643","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,11,21]]}}}