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Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine

Background: By using deceptive experimental designs, several investigations have observed that trained individuals may increase their performance when told they were given caffeine, when in fact they received a placebo (i.e., the placebo effect of caffeine). However, most of these investigations on...

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Autores principales: Filip-Stachnik, Aleksandra, Krzysztofik, Michal, Kaszuba, Magdalena, Leońska-Duniec, Agata, Czarny, Wojciech, Del Coso, Juan, Wilk, Michal
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7763627/
https://www.ncbi.nlm.nih.gov/pubmed/33322129
http://dx.doi.org/10.3390/nu12123813
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author Filip-Stachnik, Aleksandra
Krzysztofik, Michal
Kaszuba, Magdalena
Leońska-Duniec, Agata
Czarny, Wojciech
Del Coso, Juan
Wilk, Michal
author_facet Filip-Stachnik, Aleksandra
Krzysztofik, Michal
Kaszuba, Magdalena
Leońska-Duniec, Agata
Czarny, Wojciech
Del Coso, Juan
Wilk, Michal
author_sort Filip-Stachnik, Aleksandra
collection PubMed
description Background: By using deceptive experimental designs, several investigations have observed that trained individuals may increase their performance when told they were given caffeine, when in fact they received a placebo (i.e., the placebo effect of caffeine). However, most of these investigations on the placebo effect of caffeine used individuals with low caffeine consumption or did not report habitual caffeine consumption, especially in studies analyzing resistance-based exercise. Hence, it is unknown if habitual caffeine consumers benefit from the placebo effect of caffeine on exercise performance. Thus, the aim of the present study was to analyze the placebo effect of caffeine on maximal strength and strength-endurance performance during the bench press exercise (BP) in women with mild–moderate daily consumption of caffeine. Methods: Thirteen resistance-trained women (BP one-repetition maximum (1RM) = 40.0 ± 9.7 kg) habituated to caffeine (4.1 ± 1.7 mg/kg/day) completed a deceptive randomized experimental design with two experimental trials. On one occasion, participants were told that they would receive 6 mg/kg of caffeine but received a placebo (PLAC), and on other occasions, participants did not receive any substance and were told that this was a control situation (CONT). In each experimental trial, participants underwent a 1RM BP test and a strength-endurance test consisting of performing the maximal number of repetitions at 50% of their 1RM. Results: In comparison to CONT, PLAC did not enhance 1RM (40.0 ± 10.5 kg vs. 41.0 ± 9.5 kg, respectively; p = 0.10), nor did it enhance the number of repetitions (32.2 ± 5.1 vs. 31.8 ± 4.5; p = 0.66) or mean power (130 ± 34 vs. 121 ± 26; p = 0.08) in the strength-endurance test. Conclusion: Informing participants that they were given caffeine, when in fact they received a placebo, did not modify any performance variable measured in this investigation. Thus, the use of the placebo effect of caffeine seemed an ineffective strategy to enhance muscle strength and strength endurance during the BP exercise in women with mild–moderate consumption of caffeine.
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spelling pubmed-77636272020-12-27 Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine Filip-Stachnik, Aleksandra Krzysztofik, Michal Kaszuba, Magdalena Leońska-Duniec, Agata Czarny, Wojciech Del Coso, Juan Wilk, Michal Nutrients Article Background: By using deceptive experimental designs, several investigations have observed that trained individuals may increase their performance when told they were given caffeine, when in fact they received a placebo (i.e., the placebo effect of caffeine). However, most of these investigations on the placebo effect of caffeine used individuals with low caffeine consumption or did not report habitual caffeine consumption, especially in studies analyzing resistance-based exercise. Hence, it is unknown if habitual caffeine consumers benefit from the placebo effect of caffeine on exercise performance. Thus, the aim of the present study was to analyze the placebo effect of caffeine on maximal strength and strength-endurance performance during the bench press exercise (BP) in women with mild–moderate daily consumption of caffeine. Methods: Thirteen resistance-trained women (BP one-repetition maximum (1RM) = 40.0 ± 9.7 kg) habituated to caffeine (4.1 ± 1.7 mg/kg/day) completed a deceptive randomized experimental design with two experimental trials. On one occasion, participants were told that they would receive 6 mg/kg of caffeine but received a placebo (PLAC), and on other occasions, participants did not receive any substance and were told that this was a control situation (CONT). In each experimental trial, participants underwent a 1RM BP test and a strength-endurance test consisting of performing the maximal number of repetitions at 50% of their 1RM. Results: In comparison to CONT, PLAC did not enhance 1RM (40.0 ± 10.5 kg vs. 41.0 ± 9.5 kg, respectively; p = 0.10), nor did it enhance the number of repetitions (32.2 ± 5.1 vs. 31.8 ± 4.5; p = 0.66) or mean power (130 ± 34 vs. 121 ± 26; p = 0.08) in the strength-endurance test. Conclusion: Informing participants that they were given caffeine, when in fact they received a placebo, did not modify any performance variable measured in this investigation. Thus, the use of the placebo effect of caffeine seemed an ineffective strategy to enhance muscle strength and strength endurance during the BP exercise in women with mild–moderate consumption of caffeine. MDPI 2020-12-13 /pmc/articles/PMC7763627/ /pubmed/33322129 http://dx.doi.org/10.3390/nu12123813 Text en © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Filip-Stachnik, Aleksandra
Krzysztofik, Michal
Kaszuba, Magdalena
Leońska-Duniec, Agata
Czarny, Wojciech
Del Coso, Juan
Wilk, Michal
Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine
title Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine
title_full Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine
title_fullStr Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine
title_full_unstemmed Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine
title_short Placebo Effect of Caffeine on Maximal Strength and Strength Endurance in Healthy Recreationally Trained Women Habituated to Caffeine
title_sort placebo effect of caffeine on maximal strength and strength endurance in healthy recreationally trained women habituated to caffeine
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7763627/
https://www.ncbi.nlm.nih.gov/pubmed/33322129
http://dx.doi.org/10.3390/nu12123813
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