Combined Caffeine and Rhodiola Rosea on Aerial Duel Performance in Soccer

Effects of Combined Caffeine and Rhodiola Rosea Supplementation on Aerial Duel Performance Under Fatigue in Soccer Players

This study will examine whether caffeine (CAF) and Rhodiola rosea (RHO) supplementation, taken alone or in combination, can improve explosive performance and soccer-specific aerial duel performance in trained male soccer players. In a randomized, double-blind, placebo-controlled, parallel design, participants will be assigned to placebo, RHO, CAF, or RHO+CAF for 4 weeks. Performance outcomes will be assessed before and after the intervention using countermovement jump measures (including early take-off impulse) and standardized heading tests (heading reach height, ball exit velocity, and heading duel success rate), with additional measures of neck isometric strength and perceived exertion.

Inclusion Criteria:

• Healthy male soccer players from the Beijing Sport University team.

Systematic soccer-specific training background and stable competitive level.

Suitable for high-intensity physical testing based on the Physical Activity Readiness Questionnaire (PAR-Q).

Exclusion Criteria:

• History of neuromuscular or musculoskeletal system diseases.

Intake of caffeine (coffee/tea), other supplements, ergogenic aids, or alcohol within the last 3 months.

Current use of antidepressants or central nervous system stimulants.

Smokers.