Exercise Performance
Conditions
Keywords
Beetroot Juice, Dietary Nitrate, Caffeine, Coffee, Aerobic Performance, Anerobic Performance, Countermovement Jump, 20-m Shuttle Run, Recreational Athletes, Crossover Trial
Brief summary
The goal of this clinical trial was to evaluate how acute intake of beetroot juice, caffeinated coffee, and their combination affected aerobic and anaerobic exercise performance in healthy recreationally active men. The main questions were: Did beetroot juice, caffeinated coffee, or their combination improve aerobic exercise performance? Did beetroot juice, caffeinated coffee, or their combination improve countermovement jump performance? Researchers compared four conditions: control, caffeinated coffee, beetroot juice, and beetroot juice combined with caffeinated coffee. Each participant completed all four conditions in a randomized crossover design, with a 1-week washout period between sessions. Participants: Completed a familiarization session before the experimental sessions Consumed water only, caffeinated Turkish coffee, beetroot juice, or both beetroot juice and caffeinated coffee depending on the assigned condition Performed a countermovement jump test Performed a 20-m multistage shuttle run test Had heart rate and rating of perceived exertion assessed during exercise testing
Detailed description
Before each experimental session, participants were instructed to maintain their habitual diet and training routine and to avoid strenuous exercise, alcohol, caffeine-containing foods and beverages, and ergogenic aids during the preceding 24 hours. Compliance with these instructions was confirmed before testing. Participants completed a familiarization session 2 days before the first experimental session. All exercise assessments were conducted in the morning using the same standardized warm-up and test order. Countermovement jump testing was performed before the 20-m multistage shuttle run test.
Interventions
DIETARY_SUPPLEMENTBeetroot juice
Participants consumed 70 mL of concentrated beetroot juice providing 6.5 mmol of nitrate according to the manufacturer's specification. The beetroot juice was consumed approximately 2.5 hours before exercise testing.
OTHERCaffeinated Turkish Coffee
Turkish coffee was individually prepared to provide an estimated caffeine dose of 4 mg/kg body mass. The caffeine dose was calculated using an estimated caffeine content of 17 mg/g of coffee. Approximately 14-20 g of coffee was prepared with 100 mL of water and consumed approximately 60 minutes before exercise testing.
OTHERWater
During the control condition, participants received no experimental supplement and consumed water only before completing the standardized exercise testing protocol.
Sponsors
Acibadem University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
NONE
Intervention model description
Participants completed all four experimental conditions (control, caffeinated coffee, beetroot juice, and combined beetroot juice plus caffeinated coffee) in a randomized four-period crossover design. Four intervention sequences were used, and consecutive experimental periods were separated by a 1-week washout interval.
Eligibility
Sex/Gender
MALE
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
* Male recreational athletes aged 18 to 45 years * Healthy volunteers who regularly trained 4 to 5 days per week * At least 5 years of participation in sports involving high-intensity sprint-type activities * No disease or injury that prevented participation in exercise * Not following a specific diet program * No known sensitivity to caffeine or nitrate intake * Non-smoker * No use of nutritional supplements or ergogenic aids that could affect physical or cognitive performance during the previous 2 months
Exclusion criteria
* Use of performance-related nutritional supplements during the previous 2 months * Vegetarian or vegan dietary pattern * Use of non-steroidal anti-inflammatory drugs, diuretics, or laxatives * Any known food allergy or intolerance * Smoking
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Estimated Maximal Oxygen Uptake (VO₂max) | At each of the four experimental sessions; sessions were separated by a 1-week washout period. | Estimated VO2max (mL/kg/min) was calculated from the maximal running speed achieved during the 20-m multistage shuttle run test using the predefined equation. |
| Maximal Running Speed | At each of the four experimental sessions; sessions were separated by a 1-week washout period. | Highest running speed (km/h) achieved during the 20-m multistage shuttle run test. |
| Number of Completed Shuttles | At each of the four experimental sessions; sessions were separated by a 1-week washout period. | Total number of successfully completed 20-m shuttles during the multistage shuttle run test. |
| Total Distance Covered | At each of the four experimental sessions; sessions were separated by a 1-week washout period. | Total distance (m) completed during the 20-m multistage shuttle run test. |
| Countermovement Jump Height | At each of the four experimental sessions; sessions were separated by a 1-week washout period. | Maximum countermovement jump height (cm) obtained from three trials using a dual force-platform system. The highest value was used. |
| Countermovement Jump Peak Power | At each of the four experimental sessions; sessions were separated by a 1-week washout period. | Peak power (W) recorded during the countermovement jump assessment. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Mean Heart Rate | During exercise testing at each of the four experimental sessions. | Mean heart rate (beats/min) recorded during exercise testing. |
| Maximum Heart Rate | During exercise testing at each of the four experimental sessions. | Maximum heart rate (beats/min) recorded during exercise testing. |
| Rating of Perceived Exertion | Immediately after exercise testing at each of the four experimental sessions. | Rating of perceived exertion assessed using the Borg 6-20 scale. |
Countries
Turkey (Türkiye)
Outcome results
None listed