An interventional study of Acute caffeine and beetroot juice and Acute caffeine in Dietary Supplements, Caffeine and Nitrates, sponsored by University of Alcala. Completed at 1 site in Spain. Open to male participants aged 18 Years to 35 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-09-19.
Sponsored by University of Alcala · Not applicable, Interventional, and Other
Introduction: Several studies have evaluated and confirmed the ergogenic effect of acute caffeine and beetroot juice intake on sports performance. However, there are few studies focused on the production of strength, power, and muscle endurance, particularly when both supplements are ingested together.
Objectives: Evaluate the acute effect of combined and isolated intake of caffeine and beetroot juice on the production of strength, power, and muscle endurance in young adults, analyzing the effect of circadian rhythms (morning vs. afternoon) on the exercise performed (bench press vs. squat).
Methods: A total of 12 healthy and physically active participants will be recruited for the study. Through a double-blind, crossover, randomized, and controlled design, participants will ingest: a) Caffeine (3 mg/kg body mass); b) Beetroot juice (70 ml, 6.5 mmol of nitrates); c) Caffeine + Beetroot juice; d) Placebo (maltodextrin, 3 mg/kg). The supplements will be ingested 120 minutes (beetroot juice or placebo) and 60 minutes before (caffeine or placebo), the latter dissolved in 200 ml of water. After the ingestion period, strength, power, and muscle endurance will be analyzed with 1RM tests, strength and power tests at 25%, 50%, 75%, and 90% 1RM, and muscle endurance tests at 65% 1RM, in all cases for squat and bench press exercises. Additionally, dynamometry (manual and the isometric mid-thigh pull test) and vertical jump (squat jump and countermovement jump) will be analyzed. The four experimental conditions will be conducted in the morning (8:00 am to 10:00 am) and in the afternoon (4:30 pm to 6:30 pm).
University of Alcala is the lead sponsor of 123 studies on the registry; 36 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
70 mL of concentrated NO3--rich (BJ, 6.5 mmol NO3-) + 3 mg/kg of caffeine
Dietary Supplement: Acute caffeine and beetroot juice
70 mL of concentrated NO3--rich (BJ, 6.5 mmol NO3-) + 3 mg/kg of placebo (maltodextrin)
Dietary Supplement: Acute beetroot juice
70 mL of NO3--depleted (BJ, 0.04 mmol NO3-) + 3 mg/kg of caffeine
Dietary Supplement: Acute caffeine
70 mL of NO3--depleted (BJ, 0.04 mmol NO3-) + 3 mg/kg of placebo (maltodextrin)
Dietary Supplement: Placebo
Combined effect of beetroot juice and caffeine intake on muscular strength, power and endurance performance
single effect of caffeine intake on muscular strength, power and endurance performance
single effect of beetroot juice intake on muscular strength, power and endurance performance
single effect of placebo on muscular strength, power and endurance performance
Mean and peak velocity and time to reach peak velocity at different %1RM
Measuring bar velocity desplacement during bench press and back squat exercises.
Time frame: On each trial, after dietary supplement intake, during 2 weeks
Mean and peak power output and time to reach peak power output at different %1RM
Measuring power output generated during bench press and back squat exercises.
Time frame: On each trial, after dietary supplement intake, during 2 weeks
Number of repetitions performed at 65%1RM until task failure
Additionally to mean and peak velocity, mean and peak power output, time to reach peak velocity and peak power
Time frame: On each trial, after dietary supplement intake, during 2 weeks
Mood state (tension, depression, anger, vigor, fatigue and confusion)
Participants graded a set of 29 items related to the mood on a Likert scale from 0 (not at all) to 4 (extremely) in reply to the question \"How do you feel at this moment?\" to assess six scales: tension, depression, anger, vigor, fatigue and confusion.
Time frame: On each trial, after dietary supplement intake, during 2 weeks
Adverse effects
perception of power, endurance, energy and exertion, as well as heart, muscular and gastrointestinal discomfort.
Time frame: On each trial, after dietary supplement intake, during 2 weeks
handgrip and isometric mid-thigh pull tests
N generated
Time frame: On each trial, after dietary supplement intake, during 2 weeks
Vertical Jump (cm and power)
Time frame: On each trial, after dietary supplement intake, during 2 weeks
Plan to share: Yes
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This study is completed, as verified in Sep 2024. You cannot join it, but the record below documents what was studied.
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University of Alcala