Background: The ergogenic properties of acute caffeine (CAF) and sodium bicarbonate (NaHCO3) ingestion on athletic performance have been previously investigated. However, each sport has unique physiological and technical characteristics which warrants optimizing supplementations strategies for maximizing performance. This study examined the effects of CAF and NaHCO3 ingestion on physiological responses and rate of perceived exertion during a Karate-specific aerobic test (KSAT) in competitive karatekas.
Methods: In a double-blind, crossover, randomized placebo-controlled trial, eight Karatekas underwent five experimental conditions including control (CON), placebo (PLA), CAF, NaHCO3, and CAF + NaHCO3 before completing KSAT. Capsules containing 6 mg/kg BW CAF were consumed 50 min prior to a KSAT whilst 0.3 g/kg BW NaHCO3 was consumed for 3 days leading to and 120, 90, and 60 min prior to a KSAT. Time to exhaustion (TTE), rate of perceived exertion (RPE), and blood lactate (BL) were measured before, immediately after and 3 min following KSAT.
Results: TTE was significantly greater following CAF, NaHCO3, and CAF + NaHCO3 consumption compared to PLA and CON. However, the differences between CAF, NaHCO3, and CAF + NaHCO3 were not statistically significant (p > 0.05). BL increased significantly from baseline to immediately after and 3 min following KSAT in all conditions (p < 0.01), while RPE at the end of KSAT was not significantly different between conditions (p = 0.11).
Conclusions: Karate practitioners may benefit from the ergogenic effects of CAF and NaHCO3 when consumed separately or together.
Keywords: Blood lactate; Caffeine; Ergogenic aid; Karate; Karate-specific aerobic test; Rate of perceived exertion; Sodium bicarbonate; Time to exhaustion.