Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.
COMPLETED
NA
30 participants
INTERVENTIONAL
2010-01-31
2010-03-31
Brief Summary
Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.
1. Total body water and its compartments (intracellular and extracellular) assessed by by dilution techniques, and hydration state by urine specific gravity;
2. Total energy expenditure by double labeled water, resting energy expenditure by indirect calorimetry, and physical activity energy expenditure;
3. Energy expenditure in physical activity of daily living, in particular duration and intensity of activity.
4. If the changes occurred between placebo and caffeine ingestion on the main outcomes were dependent on specific covariates, namely body composition and dietary intake.
Detailed Description
Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.
To perform this research study, a total of 30 non-smoker males, low caffeine users (\<100 mg/day), aged 20-39 yrs \[body mass (BM): 72.7 ± 8.8 kg; Height: 1.77 ± 0.07 m\] were followed in a double-blind crossover experimental design with two conditions in a random sequence: caffeine (5 mg per kg of BM/day) and malt-dextrine as placebo, both through capsules. Conditions lasted for 4 days with a 3-day washout period.
Evaluations were performed at baseline (visit-1), end of condition 1 (visit-2), and end of condition 2 (visit-3). Fat and fat-free masses (FFM) were assessed by dual energy x-ray absorptiometry. TBW and ECW were determined by dilution techniques (deuterium and bromide, specifically) while ICW was calculated as the difference between TBW and ECW (Schoeller et al., 1980. Total body water measurement in humans with 18O and 2H labeled water. Am J Clin Nutr 33:2686-2693). TEE was assessed using doubly labeled water technique by administrating two stable isotopes 2H (deuterium) and 18O (oxygen 18) with a respective dose of 0.1 g / kg and 1.8 g / kg of body water (Schoeller DA, van Santen E, 1982. Measurement of energy expenditure in humans by doubly labeled water method. J Appl Physiol 53:955-959). REE was assessed by indirect calorimetry and PAEE calculated as \[TEE-(REE+0.1TEE)\]. An accelerometer (ActiGraph, GT1M model, Fort Walton Beach, Florida) was used to estimate DTSS, DTSL, DTSM, and DTSV. The cutoff values used to define the intensity of physical activity and therefore to quantify the mean time in each intensity (sedentary, light, moderate or vigorous) for persons aged 18 years or older were: sedentary: \< 100 counts/min; light: 100-2019 counts/min; moderate: 2,020-5,998 counts/min (corresponding to 3-5.9 METs); vigorous: ≥ 5999 counts/min (corresponding to ≥ 6 METs) (Troiano et al. Physical activity in the United States measured by accelerometer. Med Sci Sports Exerc. 2008;40:181-8).
Conditions
See the medical conditions and disease areas that this research is targeting or investigating.
Keywords
Explore important study keywords that can help with search, categorization, and topic discovery.
Study Design
Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.
RANDOMIZED
CROSSOVER
PREVENTION
DOUBLE
Study Groups
Review each arm or cohort in the study, along with the interventions and objectives associated with them.
Caffeine
Intervention with Caffeine in a random order
Caffeine
5 mg/ kg of body weight (capsules), twice a day (morning and afternoon), during 4 days.
Placebo
Placebo (malt dextrin) administered in a random order
Placebo
Malt dextrin (5 mg/kg body mass) twice a day during 4 days
Interventions
Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.
Caffeine
5 mg/ kg of body weight (capsules), twice a day (morning and afternoon), during 4 days.
Placebo
Malt dextrin (5 mg/kg body mass) twice a day during 4 days
Eligibility Criteria
Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.
Inclusion Criteria
* aged 18-39 years old
* body mass index between 18.5 and 29.9 kg/m2
* Subjects had to be free of any major disease with a general healthy status warranted
Exclusion Criteria
* taking medication or dietary supplements that may interfere with hydration status
* body composition or energy expenditure regulation
* Caffeine consumption \> 100 mg/day
18 Years
39 Years
MALE
Yes
Sponsors
Meet the organizations funding or collaborating on the study and learn about their roles.
Technical University of Lisbon
OTHER
Responsible Party
Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.
Analiza M Silva, PhD
Principal Investigator
Principal Investigators
Learn about the lead researchers overseeing the trial and their institutional affiliations.
Analiza M Silva, PhD
Role: PRINCIPAL_INVESTIGATOR
Faculty of Human Kinetics, Technical University of Lisbon
Locations
Explore where the study is taking place and check the recruitment status at each participating site.
Faculty of Human Kinetics
Lisbon, , Portugal
Countries
Review the countries where the study has at least one active or historical site.
References
Explore related publications, articles, or registry entries linked to this study.
Silva AM, Armada-da-Silva P, Sardinha LB, Júdice PB, Magalhães JP, Matias CN & Santos DA. Efeitos da ingestão de cafeína na água corporal total, distribuição de fluidos intra e extracelulares e no dispêndio energético. A Report for the Institution of Hydration and Health, In press.
Júdice PB (2011). Determinant Factors on hydration status assessed by Urine Specific Gravity: accuracy of technical procedures and effect of caffeine ingestion. Master's Degree Thesis. Faculty of Human Kinetics-Technical University of Lisbon, Cruz-Quebrada.
Magalhães JP, Santos DA, Silva AM, Matias CN, Júdice PB, Quintas IC, Sardinha LB (2011). Total energy expenditure: combined heart rate and motion sensor vs uni-axial accelerometry models Book of abstracts of the International conference on Recent Advances and Controversies in Measuring Energy Metabolism, pp 106.
Quintas IC, Santos DA, Matias CN, Silva AM, Gobbo, LA, Gonçalves EM, Magalhães JP, Júdice PB, Sardinha LB (2011). Does caffeine intake affect resting energy expenditure? Book of abstracts of the International conference on Recent Advances and Controversies in Measuring Energy Metabolism, pp 104.
Júdice PB, Silva AM, Magalhães JP, Matias CN, Santos DA, Armada-da-Silva P, & Sardinha LB. Does caffeine intake increases energy expenditure and habitual physical activity? A double-blind randomized crossover trial. Medicine and Science in Sports and Exercise. In Review.
Francisco R, Rosa GB, Judice PB, Magalhaes JP, Cruz AD, Sardinha LB, Lukaski HC, Silva AM. Four days of a moderate dose of caffeine does not alter raw bioelectrical impedance analysis parameters in healthy males. Clin Nutr ESPEN. 2025 Oct;69:599-607. doi: 10.1016/j.clnesp.2025.08.005. Epub 2025 Aug 6.
Silva AM, Santos DA, Matias CN, Judice PB, Magalhaes JP, Ekelund U, Sardinha LB. Accuracy of a combined heart rate and motion sensor for assessing energy expenditure in free-living adults during a double-blind crossover caffeine trial using doubly labeled water as the reference method. Eur J Clin Nutr. 2015 Jan;69(1):20-7. doi: 10.1038/ejcn.2014.51. Epub 2014 Apr 2.
Judice PB, Matias CN, Santos DA, Magalhaes JP, Hamilton MT, Sardinha LB, Silva AM. Caffeine intake, short bouts of physical activity, and energy expenditure: a double-blind randomized crossover trial. PLoS One. 2013 Jul 15;8(7):e68936. doi: 10.1371/journal.pone.0068936. Print 2013.
Silva AM, Judice PB, Matias CN, Santos DA, Magalhaes JP, St-Onge MP, Goncalves EM, Armada-da-Silva P, Sardinha LB. Total body water and its compartments are not affected by ingesting a moderate dose of caffeine in healthy young adult males. Appl Physiol Nutr Metab. 2013 Jun;38(6):626-32. doi: 10.1139/apnm-2012-0253. Epub 2013 Jan 15.
Judice PB, Magalhaes JP, Santos DA, Matias CN, Carita AI, Armada-Da-Silva PA, Sardinha LB, Silva AM. A moderate dose of caffeine ingestion does not change energy expenditure but decreases sleep time in physically active males: a double-blind randomized controlled trial. Appl Physiol Nutr Metab. 2013 Jan;38(1):49-56. doi: 10.1139/apnm-2012-0145. Epub 2013 Jan 18.
Other Identifiers
Review additional registry numbers or institutional identifiers associated with this trial.
IHS-2010
Identifier Type: -
Identifier Source: org_study_id