Caffeine and Resistance ExerciseNCT06606639
Reproducibility of Acute Caffeine Effect
A study testing Caffeine in people with Caffeine and Resistance Exercise, run by University of Alcala at 1 site in Spain.
Trial summary
Introduction: Various studies have evaluated and verified the ergogenic effect of acute caffeine intake on sports performance, specifically on strength and power performance. However, all experimental investigations designed so far have been based on the comparison of the \"caffeine\" and \"placebo\"… Read more about this study
- Who is it for?
- Ages 18 to 35 yearsHealthy volunteers can take part
- Conditions the study is for
- Caffeine and Resistance Exercise
- What is being tested?
- Caffeine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 48 participants
- Where
- 1 siteSpain
- Study dates
- 8 Jan 2024to 22 May 2024
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 35 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age between ≥ 18 and ≤ 35 years.
- Body Mass Index (BMI) \< 25 kg/m².
- Resistance-trained individuals (\> 2 years of structured trained).
- Healthy men and women without neurological, cardiometabolic, immunological, or physical conditions that prevent them from exercising.
- Participants must be able to perform the tests described in the following section.
Who cannot join
- History of neuromuscular diseases, heart diseases, or diseases that may affect liver or muscle metabolism.
- Use of drugs, other stimulants or sport supplements that interfere with the the study dietary supplement.
- Sedentary habits (\<150 min/week of moderate exercise).
- Having undergone prolonged periods of forced physical inactivity during the 6 months prior to the study.
- Performing strenuous exercise during the 48 hours prior to the tests.
- Failure to replicate the same food intake on the two days of the experiments.
- Consuming caffeine or any other stimulant after 6 pm the day before the training or tests, to avoid headaches, discomfort, or lethargy among regular caffeine consumers.
Trial locations and contacts
1 site in 1 country.
Spain1 site
Facultad de Medicina y Ciencias de la Salud. Universidad de Alcalá
Alcalá de Henares, Madrid, 28805
About this study
Official title: Reproducibility of the Acute Effect of Caffeine on Energy Metabolism and Muscular Strength, Power and Endurance Performance
Introduction: Various studies have evaluated and verified the ergogenic effect of acute caffeine intake on sports performance, specifically on strength and power performance. However, all experimental investigations designed so far have been based on the comparison of the \"caffeine\" and \"placebo\" conditions in a single trial, not considering the reproducibility and variability of caffeine in multiple trials.
Objectives: The present study aims to evaluate the reproducibility and replicability of the acute effect of caffeine intake on energy metabolism and the muscular production of force, power and endurance, according to sex (men vs women) and type of exercise ( bench press vs squat).
- Conditions
- Caffeine and Resistance Exercise
- Being tested
- Caffeine, Placebo
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CaffeineDietary supplement
acute caffeine intake (3 mg/kg)
PlaceboDietary supplement
Acute placebo intake (3 mg/kg of maltodextrin)
| Study group | Role | What they receive |
|---|---|---|
| Caffeine - Trial 1 | Experimental | Not described Receives: Dietary Supplement: Caffeine |
| Caffeine - Trial 2 | Experimental | Not described Receives: Dietary Supplement: Caffeine |
| Caffeine - Trial 3 | Experimental | Not described Receives: Dietary Supplement: Caffeine |
| Placebo - Trial 1 | Placebo comparator | Not described Receives: Dietary Supplement: Placebo |
| Placebo - Trial 2 | Placebo comparator | Not described Receives: Dietary Supplement: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Mean velocity at different %1RM
Measuring bar mean velocity desplacement during bench press and back squat exercises.
Measured: Through study completion, an average of 4 weeks
Peak velocity at different %1RM
Measuring bar peak velocity and time to reach peak velocity of bar desplacement during bench press and back squat exercises.
Measured: Through study completion, an average of 4 weeks
Mean power output at different %1RM
Measuring during bench press and back squat exercises.
Measured: Through study completion, an average of 4 weeks
Peak power output and time to reach peak power output at different %1RM
Measuring during bench press and back squat exercises.
Measured: Through study completion, an average of 4 weeks
Number of repetitions performed in 1 set at 65%1RM until task failure
In bench press and back squat exercises
Measured: Through study completion, an average of 4 weeks
Bar velocity deplacement performed in 1 set at 65%1RM until task failure
In bench press and back squat exercises
Measured: Through study completion, an average of 4 weeks
Power output generated in 1 set at 65%1RM until task failure
In bench press and back squat exercise
Measured: Through study completion, an average of 4 weeks
Resting Metabolic Rate (RMR)
Kcal at rest measuring (RMR) using a metabolic chart.
Measured: Through study completion, an average of 4 weeks
Maximal Fat Oxidation Rate (MFO)
g/min (MFO) using a metabolic chart.
Measured: Through study completion, an average of 4 weeks
Secondary outcomes (6)
Physical activity (METs-min/wk)
Using IPAQ
Measured: Through study completion, an average of 4 weeks
Dietary (g/kg of macronutrients)
Using 24-total recall
Measured: Through study completion, an average of 4 weeks
Mood state
Mood. 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.
Measured: Through study completion, an average of 4 weeks
Adverse effects
Adverse effects. perception of power, endurance, energy and exertion, as well as heart, muscular and gastrointestinal discomfort.
Measured: Through study completion, an average of 4 weeks
Fat mass
Using electrical bioimpedance (kg and % of body mass)
Measured: Through study completion, an average of 4 weeks
Fat-free mass
Using electrical bioimpedance (kg and % of body mass)
Measured: Through study completion, an average of 4 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Sep 2024
- Study start8 Jan 2024
- Primary completion22 May 2024
- Study completion22 May 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Caffeine and Resistance ExerciseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 48 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Alcala
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Alberto Pérez-López, University of Alcala
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06606639
- Sponsor's protocol ID
- CEID/2024/2/039
- Status last verified
- May 2025
- First submitted
- 9 Sep 2024
- Last updated
- 25 May 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 25 May 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Reproducibility of the Acute Effect of Caffeine on Energy Metabolism and Muscular Strength, Power and Endurance Performance
- ClinicalTrials.gov ID
- NCT06606639
- Acronym / sponsor ID
- CEID/2024/2/039
- Conditions
- Caffeine and Resistance Exercise
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 48 participants (actual)
- Lead sponsor
- University of AlcalaUniversity, hospital or other
- Study start
- 8 Jan 2024 (actual)
- Primary completion
- 22 May 2024 (actual)
- Study completion
- 22 May 2024 (actual)
- First posted
- 23 Sep 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Introduction: Various studies have evaluated and verified the ergogenic effect of acute caffeine intake on sports performance, specifically on strength and power performance. However, all experimental investigations designed so far have been based on the comparison of the \"caffeine\" and \"placebo\" conditions in a single trial, not considering the reproducibility and variability of caffeine in multiple trials.
Objectives: The present study aims to evaluate the reproducibility and replicability of the acute effect of caffeine intake on energy metabolism and the muscular production of force, power and endurance, according to sex (men vs women) and type of exercise ( bench press vs squat).
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, investigator)
- Number of arms
- 5
| Arm | Type | Receives |
|---|---|---|
| Caffeine - Trial 1 | Experimental | Dietary Supplement: Caffeine |
| Caffeine - Trial 2 | Experimental | Dietary Supplement: Caffeine |
| Caffeine - Trial 3 | Experimental | Dietary Supplement: Caffeine |
| Placebo - Trial 1 | Placebo comparator | Dietary Supplement: Placebo |
| Placebo - Trial 2 | Placebo comparator | Dietary Supplement: Placebo |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Age between ≥ 18 and ≤ 35 years.
- Body Mass Index (BMI) \< 25 kg/m².
- Resistance-trained individuals (\> 2 years of structured trained).
- Healthy men and women without neurological, cardiometabolic, immunological, or physical conditions that prevent them from exercising.
- Participants must be able to perform the tests described in the following section.
Key exclusion criteria (7 listed)
- History of neuromuscular diseases, heart diseases, or diseases that may affect liver or muscle metabolism.
- Use of drugs, other stimulants or sport supplements that interfere with the the study dietary supplement.
- Sedentary habits (\<150 min/week of moderate exercise).
- Having undergone prolonged periods of forced physical inactivity during the 6 months prior to the study.
- Performing strenuous exercise during the 48 hours prior to the tests.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Caffeineacute caffeine intake (3 mg/kg) | Dietary supplement | Caffeine - Trial 1, Caffeine - Trial 2, Caffeine - Trial 3 |
| PlaceboAcute placebo intake (3 mg/kg of maltodextrin) | Dietary supplement | Placebo - Trial 1, Placebo - Trial 2 |
Primary outcome
Mean velocity at different %1RM
Time frame: Through study completion, an average of 4 weeks
Measuring bar mean velocity desplacement during bench press and back squat exercises.
Peak velocity at different %1RM
Time frame: Through study completion, an average of 4 weeks
Measuring bar peak velocity and time to reach peak velocity of bar desplacement during bench press and back squat exercises.
Mean power output at different %1RM
Time frame: Through study completion, an average of 4 weeks
Measuring during bench press and back squat exercises.
Peak power output and time to reach peak power output at different %1RM
Time frame: Through study completion, an average of 4 weeks
Measuring during bench press and back squat exercises.
Number of repetitions performed in 1 set at 65%1RM until task failure
Time frame: Through study completion, an average of 4 weeks
In bench press and back squat exercises
Bar velocity deplacement performed in 1 set at 65%1RM until task failure
Time frame: Through study completion, an average of 4 weeks
In bench press and back squat exercises
Power output generated in 1 set at 65%1RM until task failure
Time frame: Through study completion, an average of 4 weeks
In bench press and back squat exercise
Resting Metabolic Rate (RMR)
Time frame: Through study completion, an average of 4 weeks
Kcal at rest measuring (RMR) using a metabolic chart.
Maximal Fat Oxidation Rate (MFO)
Time frame: Through study completion, an average of 4 weeks
g/min (MFO) using a metabolic chart.
6 secondary outcomes
Physical activity (METs-min/wk)
Time frame: Through study completion, an average of 4 weeks
Dietary (g/kg of macronutrients)
Time frame: Through study completion, an average of 4 weeks
Mood state
Time frame: Through study completion, an average of 4 weeks
Adverse effects
Time frame: Through study completion, an average of 4 weeks
Fat mass
Time frame: Through study completion, an average of 4 weeks
Fat-free mass
Time frame: Through study completion, an average of 4 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 25 May 2025.
- Individual participant dataSharing planned: Yes
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Caffeine in people with Caffeine and Resistance Exercise, run by University of Alcala at 1 site in Spain.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 25 May 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Spain. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Mean velocity at different %1RM (time frame: Through study completion, an average of 4 weeks). The study lists 9 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 25 May 2025.