Determining the Levels of Cortisol, Testosterone, Lactic Acid and Anaerobic Performance in Athletes Using Various Forms of Coffee

Abstract

Background: Coffee is considered one of the most preferred and consumed beverage types in the world, and caffeine is known to increase physical performance due to its ergogenic properties. The aim of this study is to examine the effects of coffee consumption in different forms on cortisol, testosterone, lactic acid and anaerobic performance levels.

Methods: A total of 15 licensed male football players participated in the research voluntarily. The research was implemented in a single-blind, counterbalanced, randomized and crossover study design. Participants were given caffeinated coffee (CK), decaffeinated coffee (placebo) (DK), powdered caffeine (in a gelatin capsule) (PC) and powdered placebo (maltodextrin in a capsule) (PM) on different days, and the Wingate test protocol was performed after the warm-up protocol. Blood samples were collected post-test. Cortisol, testosterone and lactic acid levels in the serum samples taken were determined by the ELISA method.

Results: As a result, it was revealed that caffeinated coffee given to participants who exercise increased anaerobic power. However, it was observed that lactic acid levels were higher in placebo and decaffeinated coffee. The highest level of cortisol was found in caffeinated coffee and powdered caffeine compared to the placebo. Testosterone values were observed to be highest in caffeinated coffee and decaffeinated coffee compared to a placebo.

Conclusions: The study suggests that the type of caffeine is a factor that affects absorption rate, which impacts performance and hormone levels.

Keywords: biochemical markers; caffeine; coffee; exercise physiology; hormone; metabolism; perform aid; physical performance; wingate test.

Figure 1

Experimental Design.

Figure 2

(A) Cortisol, (B) Lactic Acid and (C) Testosterone levels. DK (Decaffeinated Coffee (Placebo), CK (Caffeinated Coffee), PC (Powdered Caffeine in a gelatin capsule), PM (Powdered Caffeine placebo maltodextrin in a capsule). F: ANOVA variance ratio, p: statistical significance value (p < 0.05), η_p²: eta squared effect size. a, b, c, d: There are statistically significant differences between measurements marked with different letters (p < 0.05).

Figure 3

(A) Max Power, (B) Max Power (Watt/kg), (C) Average Power and (D) Average Power (Watt/kg). DK (Decaffeinated Coffee (Placebo), CK (Caffeinated Coffee), PC (Powdered Caffeine in a gelatin capsule), PM (Powdered Caffeine placebo maltodextrin in a capsule). F: ANOVA variance ratio, p: statistical significance value (p < 0.05). η_p²: eta squared effect size. a, b, c, d: There are statistically significant differences between measurements marked with different letters (p < 0.05).