NCT07056231

Effect of Low-Dose Caffeine on Performance in Elite Sitting Volleyball Players

The Effect of Low Dose Caffeine on Serve Speed, Spike Speed, and Speed-Endurance in Elite Sitting Volleyball Players: A Randomized Double-Blind Crossover Study

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 13 (actual)
• Sponsor: Ulaç Can YILDIRIM · Academic / Other
• Sex: Male
• Age: 18 Years – 35 Years
• Healthy volunteers: Not accepted

Summary

Background: Sitting volleyball is a sport that relies primarily on upper body strength and anaerobic capacity. In critical in-game skills such as serve and spike, factors such as speed-endurance time and impact power play a decisive role in performance. There are limited studies in the literature examining the effects of low-dose caffeine consumption on these skills. The effects of ergogenic supplements in Paralympic sports have not been sufficiently investigated, and the potential benefits of caffeine on serve and spike performance in sitting volleyball players remain unclear. Purpose: The main purpose of this research was to determine the effects of low-dose caffeine (3 mg/kg) consumption on the serve speed, spike speed and Speed-Endurance performances of elite-level sitting volleyball players. Method: The study was designed using a randomized, double-blind, balanced, and crossover experimental design. 13 elite male athletes from the 2024 Paravolley European Champion Sitting Volleyball Men's National Team participated in the study. Participants were evaluated for serve speed, spike speed, and speed-endurance performances in both 3 mg/kg caffeine (CAF) and placebo (PLA) conditions.

Detailed description

This study aimed to investigate the effects of low-dose caffeine ingestion on key performance parameters in elite-level sitting volleyball athletes. Sitting volleyball is a Paralympic sport that relies heavily on upper body explosive strength and short-term anaerobic power. While caffeine is a well-known ergogenic aid in able-bodied sports, its role in Paralympic contexts remains underexplored. Using a randomized, double-blind, placebo-controlled crossover design, the effects of 3 mg/kg caffeine consumption were assessed in 13 elite male sitting volleyball players. Each participant completed performance assessments under both caffeine and placebo conditions. The primary goal was to examine whether caffeine intake would enhance serve speed, spike speed, and repeated sprint ability. The study provides new insights into the acute ergogenic effects of caffeine in Paralympic team sport athletes, highlighting its selective benefit on explosive upper-body tasks such as serving.

Conditions

• Caffeine
• Physical Endurance
• Muscle Strength
• Paralympic Athletes

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Caffeine	A single oral dose of 3 mg of caffeine per kilogram of body weight form approximately 60 minutes before performance testing. Supplied by Oxford Vitality, ISO-certified.
DIETARY_SUPPLEMENT	Placebo	polydextrose used as Placebo

Timeline

• Start date: 2025-03-05
• Primary completion: 2025-03-11
• Completion: 2025-03-12
• First posted: 2025-07-09
• Last updated: 2025-07-09

Locations

1 site across 1 country: Turkey (Türkiye)