Researchers in Turkey investigated the effects of acute supplementation, both individually and in combination, in professional football players. The synergistic combination outperformed individual supplementation in measures of performance and cognition.
“This synergy may have potential for helping athletes achieve optimal performance levels in sports such as football, where both physical and cognitive performance are critically important,” they wrote in Frontiers in Nutrition.
Complementary roles
L-carnosine and L-tyrosine have distinct yet complementary roles in sports nutrition.
L-carnosine acts within muscle fibers to buffer hydrogen ions that accumulate during intensive exercise, helping maintain muscle contraction. It also helps reduce oxidative stress and muscle damage during the repeated explosive sprints demanded in football.
In contrast, L-tyrosine serves as a precursor to key neurotransmitters such as dopamine and norepinephrine, helping maintain focus and motor control during periods of stress and fatigue.
The study authors noted that combined acute supplementation “may be most relevant in contexts involving repeated high-intensity efforts and rapid decision-making, such as congested fixture periods, the closing stages of matches, or intensified training blocks.”
Study details
The randomized, double-blind, placebo-controlled crossover trial involved 24 male professional football players aged 18-30 who were actively competing in the Turkish Football Federation’s Third League.
Participants completed four intervention sessions separated by a 96-hour washout period, a timeframe consistent with the clearance rates of both compounds.
The four supplementation conditions were L-carnosine (L-CAR), L-tyrosine (L-TYR), a combination of both ( L-CAR + L-TYR) and a placebo.
L-CAR was administered at 6 mg/kg body weight, and L-TYR at 150 mg/kg body weight; participants were advised to avoid additional foods rich in these compounds for at least 24 hours before testing.
On each test day, the players consumed the oral supplement an hour before physical and cognitive performance assessments, and the researchers analyzed blood samples for lactate levels.
The results showed that while L-carnosine primarily enhanced anaerobic capacity and L-tyrosine sharpened cognitive focus, the combined condition yielded the most pronounced ergogenic benefits across the board.
The combination increased peak power by approximately 17% and average power by around 16%, while reducing the time required to reach peak power.
The combined supplements also reduced sprint and agility times between 7% and 13%, improved football-specific passing accuracy by approximately 17% and reaction times by around 15% compared to placebo.
Perceived exertion was lower with the combined supplement, and blood lactate levels did not differ between conditions.
Noting the small sample size and acute nature of the study, the researchers recommended larger, more diverse cohorts for future studies to confirm their preliminary results.
Source: Frontiers in Nutrition. doi: 10.3389/fnut.2026.1868802; “Combined L-carnosine and L-tyrosine supplementation as an ergogenic strategy for physical and cognitive performance under fatigue in professional football players.” Authors: S. Bilgin et al.
