ClimbingClimbing&CAFNCT07333443
Caffeine and Sport Climbing Performance
A study testing Acute and moderate dose of caffeine (3 mg/kg body mass) in people with Climbing and Caffeine, run by University of Alcala at 1 site in Spain.
Trial summary
To determine the effects of ingesting caffeine at a dose of 3 mg/kg body mass on pull-up performance and handgrip-related measures in trained climbers. Read more about this study
- Who is it for?
- Ages 18 to 35 years, men onlyHealthy volunteers can take part
- What is being tested?
- Acute and moderate dose of caffeine (3 mg/kg body mass)
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 13 participants
- Where
- 1 siteSpain
- Study dates
- 8 Jan 2025to 30 Oct 2025
- 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
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy individuals
- Age between 18 and 40 years
- At least three months of continuous climbing practice
- Ability to hang for at least 5 seconds from an 18-mm edge
- Ability to perform at least one strict body-weight pull-up
Who cannot join
- Any musculoskeletal or medical condition preventing completion of the experimental protocol
- Participation in less than three training sessions per week or a total training volume <150 min/week
- Use of medications or dietary supplements known to affect caffeine metabolism
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: Caffeine Ingestion at Acute and Moderate Doses Does Not Improve Sport Climbing Performance: Results From a Randomized Controlled Trial.
To determine the effects of ingesting caffeine at a dose of 3 mg/kg body mass on pull-up performance and handgrip-related measures in trained climbers.
Read the detailed description
Introduction: Caffeine is widely recognized as a performance-enhancing substance across numerous athletic disciplines; however, its role in sport climbing has received comparatively limited scientific attention. Because climbing performance relies heavily on grip force, explosive upper-body strength, and localized muscular endurance, this investigation evaluated the short-term impact of a low caffeine dose on climbing-relevant performance outcomes.
Objective: To determine the effects of ingesting caffeine at a dose of 3 mg/kg body mass on pull-up performance and handgrip-related measures in trained climbers.
Methods: Thirteen trained young male climbers participated in a triple-blind, randomized, crossover study design, completing two experimental conditions (caffeine and placebo). Performance assessments included a pull-up one-repetition maximum (1RM), a pull-up power test conducted at multiple external loads, a pull-up endurance test, and several grip performance evaluations, namely maximal dead-hang duration, maximal dead-hang force, and rate of force development (RFD).
- Being tested
- Acute and moderate dose of caffeine (3 mg/kg body mass), Placebo
- Keywords
- sport climbing, grip strength, pull up strength, caffeine, sport performance
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Acute and moderate dose of caffeine (3 mg/kg body mass)Dietary supplement
Caffeine supplementation was provide to young male climbers.
PlaceboDietary supplement
Placebo supplementation was provide to young male climbers.
| Study group | Role | What they receive |
|---|---|---|
| Placebo | Placebo comparator | 0 mg/kg of caffeine Receives: Dietary Supplement: Placebo |
| Caffeine | Experimental | 3 mg/kg of caffeine Receives: Dietary Supplement: Acute and moderate dose of caffeine (3 mg/kg body mass) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Pull-up 1RM
Measured: Through study completion, an average of 4 weeks
Pull-up strength and power test 1
Mean and peak velocity will be recorded at 60%, 80%, 90%, 95% and 100% 1RM.
Measured: Through study completion, an average of 4 weeks
Pull-up strength and power test 2
Mean and peak power will be recorded at 60%, 80%, 90%, 95% and 100%1RM.
Measured: Through study completion, an average of 4 weeks
Pull-up muscular endurance test
Using body mass and perform one set of many repetitions as possible until task failure. The total number of repetitions, Vmean, Vpeak, Wmean and Wpeak were recorded.
Measured: Through study completion, an average of 4 weeks
Grip endurance in dead-hang.
Maximum hanging time (MHT) test at an 18-mm edge depth with each hand
Measured: Through study completion, an average of 4 weeks
Maximum grip strength in dead-hang
using the Strength Test (ST), which measures the maximal external load a participant can sustain for 5 seconds while hanging from an 18-mm edge
Measured: Through study completion, an average of 4 weeks
Grip rate of force development (RFD).
measuring the maximal one-hand pull (voluntary contraction) at an 18 mm edge with a force sensor
Measured: Through study completion, an average of 4 weeks
Secondary outcomes (5)
Body composition
Using bioelectrical impedance
Measured: Through study completion, an average of 4 weeks
Dietary habits
24 h dietary recall
Measured: Through study completion, an average of 4 weeks
Physical activity habits
International Physical Activity Questionnaire (IPAQ). Report the unabbreviated scale title. Scores are typically expressed as MET-minutes/week or by activity categories (low, moderate, high), depending on the scoring protocol used. There is no fixed universal minimum or maximum score for MET-minutes/week, as scores depend on reported activity levels. Higher scores indicate better outcomes (greater physical activity).
Measured: Through study completion, an average of 4 weeks
Rate of perceived exertion
Using Rating of Perceived Exertion (RPE). Category Ratio 10 (CR10) Scale: minimum 0, maximum 10 (or 11 if including "maximal"). Higher scores indicate worse outcomes (greater perceived exertion).
Measured: Through study completion, an average of 4 weeks
Mood states
Using the Profile of Mood States (POMS) on a 0-4 scale.
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 posted12 Jan 2026
- Study start8 Jan 2025
- Primary completion30 Mar 2025
- Study completion30 Oct 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for ClimbingStudies 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- A triple-blind, randomized, placebo-controlled design
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 13 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
- Investigators
- Alberto Pérez López, PhD, Principal investigator, University of Alcala
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07333443
- Sponsor's protocol ID
- CEIP/2024/5/117
- Other IDs
- CEIP/2024/5/117
- Acronym
- Climbing&CAF
- Status last verified
- Dec 2025
- First submitted
- 15 Dec 2025
- Last updated
- 6 May 2026
- 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 6 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Caffeine Ingestion at Acute and Moderate Doses Does Not Improve Sport Climbing Performance: Results From a Randomized Controlled Trial.
- ClinicalTrials.gov ID
- NCT07333443
- Acronym / sponsor ID
- Climbing&CAF / CEIP/2024/5/117
- Keywords
- sport climbing, grip strength, pull up strength, caffeine, sport performance
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 13 participants (actual)
- Lead sponsor
- University of AlcalaUniversity, hospital or other
- Study start
- 8 Jan 2025 (actual)
- Primary completion
- 30 Mar 2025 (actual)
- Study completion
- 30 Oct 2025 (actual)
- First posted
- 12 Jan 2026 (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.
To determine the effects of ingesting caffeine at a dose of 3 mg/kg body mass on pull-up performance and handgrip-related measures in trained climbers.
Detailed description
Introduction: Caffeine is widely recognized as a performance-enhancing substance across numerous athletic disciplines; however, its role in sport climbing has received comparatively limited scientific attention. Because climbing performance relies heavily on grip force, explosive upper-body strength, and localized muscular endurance, this investigation evaluated the short-term impact of a low caffeine dose on climbing-relevant performance outcomes.
Objective: To determine the effects of ingesting caffeine at a dose of 3 mg/kg body mass on pull-up performance and handgrip-related measures in trained climbers.
Methods: Thirteen trained young male climbers participated in a triple-blind, randomized, crossover study design, completing two experimental conditions (caffeine and placebo). Performance assessments included a pull-up one-repetition maximum (1RM), a pull-up power test conducted at multiple external loads, a pull-up endurance test, and several grip performance evaluations, namely maximal dead-hang duration, maximal dead-hang force, and rate of force development (RFD).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- A triple-blind, randomized, placebo-controlled design
| Arm | Type | Receives |
|---|---|---|
| Placebo | Placebo comparator | Dietary Supplement: Placebo0 mg/kg of caffeine |
| Caffeine | Experimental | Dietary Supplement: Acute and moderate dose of caffeine (3 mg/kg body mass)3 mg/kg of caffeine |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Healthy individuals
- Age between 18 and 40 years
- At least three months of continuous climbing practice
- Ability to hang for at least 5 seconds from an 18-mm edge
- Ability to perform at least one strict body-weight pull-up
Key exclusion criteria (3 listed)
- Any musculoskeletal or medical condition preventing completion of the experimental protocol
- Participation in less than three training sessions per week or a total training volume <150 min/week
- Use of medications or dietary supplements known to affect caffeine metabolism
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 |
|---|---|---|
| Acute and moderate dose of caffeine (3 mg/kg body mass)Caffeine supplementation was provide to young male climbers. | Dietary supplement | Caffeine |
| PlaceboPlacebo supplementation was provide to young male climbers. | Dietary supplement | Placebo |
Primary outcome
Pull-up 1RM
Time frame: Through study completion, an average of 4 weeks
Pull-up strength and power test 1
Time frame: Through study completion, an average of 4 weeks
Mean and peak velocity will be recorded at 60%, 80%, 90%, 95% and 100% 1RM.
Pull-up strength and power test 2
Time frame: Through study completion, an average of 4 weeks
Mean and peak power will be recorded at 60%, 80%, 90%, 95% and 100%1RM.
Pull-up muscular endurance test
Time frame: Through study completion, an average of 4 weeks
Using body mass and perform one set of many repetitions as possible until task failure. The total number of repetitions, Vmean, Vpeak, Wmean and Wpeak were recorded.
Grip endurance in dead-hang.
Time frame: Through study completion, an average of 4 weeks
Maximum hanging time (MHT) test at an 18-mm edge depth with each hand
Maximum grip strength in dead-hang
Time frame: Through study completion, an average of 4 weeks
using the Strength Test (ST), which measures the maximal external load a participant can sustain for 5 seconds while hanging from an 18-mm edge
Grip rate of force development (RFD).
Time frame: Through study completion, an average of 4 weeks
measuring the maximal one-hand pull (voluntary contraction) at an 18 mm edge with a force sensor
5 secondary outcomes
Body composition
Time frame: Through study completion, an average of 4 weeks
Dietary habits
Time frame: Through study completion, an average of 4 weeks
Physical activity habits
Time frame: Through study completion, an average of 4 weeks
Rate of perceived exertion
Time frame: Through study completion, an average of 4 weeks
Mood states
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 6 May 2026.
- Individual participant dataSharing planned: Yes
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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.
Alberto Pérez López, PhD principal investigator
University of Alcala
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Acute and moderate dose of caffeine (3 mg/kg body mass) in people with Climbing and Caffeine, 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 3 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 6 May 2026. 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?
Pull-up 1RM (time frame: Through study completion, an average of 4 weeks). The study lists 7 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 6 May 2026; AzTrials last refreshed its copy on 31 Oct 2026.