Effects of Beetroot Juice and Caffeinated Coffee on Exercise Performance in Recreationally Active Men

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.

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