Effects of Acute Caffeine Supplementation in Paralympic Powerlifting Training on Static Strength and Oxidative Stress Parameters

Paralympic Powerlifting is a maximal strength sport that requires high training intensity and efficient recovery to maintain performance and prevent injury. Intense training can induce oxidative stress, potentially compromising performance and physiological adaptation. Caffeine (CA) is a widely used ergogenic aid with potential to enhance muscle strength and reduce oxidative damage. This study investigated the acute effects of CA supplementation (9 mg/kg) on static strength indicators and oxidative stress markers in 14 male Paralympic powerlifting athletes. The protocol included two conditions (CA and placebo), with athletes performing 5 sets of 5 repetitions at 80% of 1 RM in the adapted bench press. Strength variables (maximal isometric force, 1-s peak force, and force variability) and biomarkers (TBARS/MDA, total antioxidant capacity, sulfhydryl groups, and uric acid) were analyzed. CA supplementation significantly increased maximal isometric strength, improved 1-s peak force, and reduced variability, suggesting enhanced motor unit recruitment. However, CA also led to increased oxidative stress, as evidenced by elevated TBARS levels, reduced antioxidant capacity, decreased sulfhydryl groups, and higher uric acid concentrations post-exercise. In conclusion, while CA acutely improves neuromuscular performance, it does not attenuate—and may even exacerbate—exercise-induced oxidative stress. Therefore, its use in strength sports should be approached with caution.