A Randomized Study to Examine the Ability of a Caffeine-Based Energy Drink to Impact Energy Expenditure, Fat Oxidation, Reaction Time, and Other Perceptual Indicators

The purpose of this study is to evaluate the changes in energy expenditure, fat oxidation, reaction time, and perceptual indicators of energy and focus after acute ingestion of a caffeine-based energy drink. Approximately 60 healthy adults aged 18-50 will be recruited for a randomized, double-blind, placebo-controlled study. They will undergo baseline measurements for energy expenditure, fat and carbohydrate oxidation, reaction time, cognition, and perceptual indicators of energy, focus, and concentration. After 28 days, these measurements will be taken again, comparing the effects of a caffeine-based energy drink versus a placebo.

The study will be conducted using a randomized, double-blind, placebo-controlled, parallel study design. Approximately 60 healthy men and women between the ages of 18 - 55 years of age will be recruited to participate in this study. Prior to beginning the study, all participants will sign an IRB-approved informed consent document and complete a health history questionnaire to determine study eligibility. All participants will report to the laboratory for all study visits between 0600 - 1000 hours. Prior to each study visit, participants will be asked to abstain from exercise, tobacco, nicotine, and alcohol for 12 hours and observe an overnight (8 - 10 hours) fast including caffeine. Study visit 1 will be a screening visit where participants will first sign an IRB-approved informed consent document. To determine eligibility, participants will then complete a health and medical history form and have their height and weight assessed along with their resting heart rate and blood pressure. If determined eligible, study participants will then have their body composition assessed and then be asked to record their past 24-hour intake of food and fluid. This form will be copied and all participants will be instructed to replicate this diet prior to each visit. Study visits 2 and 3 will be identical and separated by approximately 28 days whereby each study participant will have ingested a single dose of their assigned beverage each day between visits 2 and 3. Prior to these visits, participants will not be allowed to exercise within 24 hours of each subsequent study visit and may only partake in a light workout two days prior to their study visit. Participants will be instructed to follow an overnight fast whereby no food or fluid with calories will be consumed for the 8 to 10-hour period prior to each study visit. Water intake will be encouraged during this time for appropriate hydration status. Upon arrival for study visits 2 and 3, body mass will be assessed before having their body temperature, resting heart rate, and blood pressure assessed. From there, participants will be instructed to complete simple and choice reaction time and cognition assessments using a DynaVision board. After cognition assessments are completed, visual analog scales will be completed to assess perceived levels of energy, focus, and concentration. Finally, participants will then complete a resting metabolic assessment to evaluate rates of calorie burning (energy expenditure), rate of fat oxidation, and amount of fat oxidized. After completion of all assessments, participants will ingest their assigned dose of beverage. Each participant will be given 15 minutes to ingest their assigned beverage. As soon as the entire beverage is consumed, the study protocol timer will be activated and all subsequent assessments will occur as outlined. During visit 2 (dose 1) and visit 3 (dose 28), participants will have energy expenditure and fat oxidation assessments completed 0, 30, 60, 90, and 120 minutes after ingestion while cognition, hemodynamics, and VAS will be evaluated 0, 60, and 120 minutes. Participants will be assigned to each group in a randomized, double-blind, placebo-controlled fashion with parallel groups that are matched according to BMI and gender. This will ensure each study condition has similar numbers of males and females that are of similar body mass index levels. After completion of study visit 2, participants will be provided with a 14-day supply of their assigned beverage. After 14 days, participants must return to the laboratory to pick up their remaining assigned beverage and communicate with research staff about compliance, adverse events, etc. After 28 days of supplementation, participants will return to the laboratory for study visit 3, which will complete their participation in the study.