The Effects of Acute Nitrate and Caffeine Co-ingestion on Discipline-Specific Exercise Performance. (NCT07748416) | Clinical Trial Compass
Not Yet RecruitingNot Applicable
The Effects of Acute Nitrate and Caffeine Co-ingestion on Discipline-Specific Exercise Performance.
Poland112 participantsStarted 2026-10-01
Plain-language summary
The purpose of this study is to investigate the acute, separate, and combined ergogenic effects of dietary nitrate (beetroot juice, BJ) and caffeine (CAF) supplementation on discipline-specific athletic performance. The project employs a double-blind, randomized, placebo-controlled, four-arm crossover design. It evaluates two highly distinct, heterogeneous populations of athletes: (A) adult high-intensity functional training (HIFT/CrossFit/Hyrox) competitors performing the standardized Hyrox Physical Fitness Test (P'F'T), and (B) elite junior competitive swimmers (National Team members) performing a progressive 8 × 100 m swimming test. The study will assess physical performance, lactate kinetics, subjective exertion, biochemical indices, psychological metrics, and gastrointestinal tolerance.
Who can participate
Age range
16 Years – 45 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
A) Cohort A (HIFT / CrossFit / Hyrox):
* Aged 18-45 years.
* Minimum of 2 years of systematic HIFT/CrossFit/Hyrox training experience.
* Performing \>4 training sessions per week.
* Ability to perform the HYROX Physical Fitness Test (P'F'T) and has participated in at least one official HYROX event.
* Possession of a valid medical certificate proving eligibility for competitive sports.
B) Cohort B (Competitive Junior Swimmers):
* Aged 16-19 years.
* Active member of the Polish Junior National Swimming Team.
* Minimum of 5 years of competitive swimming experience.
* Current training volume of at least 8-10 pool training sessions per week.
* Written informed consent obtained from both the participant and their legal guardian (for minors under 18).
C)Common Criteria for Both Cohorts:
* No history of cardiovascular, respiratory, metabolic, or musculoskeletal disease contradicting high-intensity exercise or stimulant intake.
* No known food allergies or adverse reactions to beetroot products or caffeine.
* No current use of medications that alter nitrate/caffeine metabolism (e.g., proton pump inhibitors, antibiotics, phosphodiesterase inhibitors).
* History of uneventful habituation to caffeine use during training/competition.
* Willingness to abstain from dietary supplements, antibacterial mouthwashes, alcohol, and high-nitrate foods for 48 hours prior to each testing session.
* Good general health and physical well-being.
Exclusion Criteria (Applicable …
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Exercise Performance Time (minutes and seconds, Cohort A - Hyrox P'F'T)
Timeframe: At each experimental visit (Visits T1-T4), with visits conducted at 7-day intervals following the baseline/familiarization visit (T0).
2
Swimming Performance (minutes and seconds, Cohort B - 8x100m Step-Test)
Timeframe: At each experimental visit (Visits T1-T4), with visits conducted at 7-day intervals following the baseline/familiarization visit (T0).