Effects of Creatine and Sodium Bicarbonate Supplementation on Exercise Performance in Elite Taekwondo Players
Authors: Koozehchian Majid S. , Sarshin Amir , Fallahi Vahid , Rahimi Alireza , Kaviani Mojtaba , Forbes Scott , Candow Darren G. , Artioli Guilherme , Naderi Alireza 
Published: April 2020

BackgroundIngesting creatine and sodium bicarbonate alone or together improves anaerobic performance; however, the combined effects on taekwondo athletes remain unknown.METHODSIn a double‐blind, randomized, placebo‐controlled study, 40 elite male taekwondo athletes (21.4±1y; 180.5±7.31cm; 72.7±8.59kg) were assigned to 5 groups: creatine monohydrate+sodium bicarbonate (Cr+SB: 20gr Cr+0.5gr.kg−1 SB+0.5g.kg−1maltodextrin), creatine monohydrate (Cr: 20gr Cr+0.5g.kg−1 maltodextrin), sodium bicarbonate (SB: 0.5gr.kg−1 SB+0.5g.kg−1 maltodextrin), placebo (PL: 20gr cellulose+0.5g.kg−1 maltodextrin), and control (CO). Participants ingested assigned supplements for 5d. A day before and after supplementation, Taekwondo Anaerobic Intermittent Kick Test (TAIKT) was conducted in 3 rounds with a 1min passive rest to simulate the taekwondo match. Peak power (PP), mean power (MP), and fatigue index (FI) were calculated. Blood lactate (BL) levels were measured before, immediately after, and 3–5min after the test in the baseline and follow‐up sessions. Rate of perceived exertion (RPE) was measured after each round in the pre‐ and post‐test. Data were analyzed using a two‐way analysis of covariance (p≤0.05).RESULTSResults showed that the interaction was significant for PP and MP in rounds 1, 2, 3, and an average of all rounds (P<0.05), but FIs were not significant for any rounds (P>0.05). After supplementation, PP and MP in all rounds and the average increased in Cr+SB, Cr, and SB (P<0.05), but not in PL and CO. The average FI of rounds was less in Cr+SB and SB (P<0.05) following supplementation. PP in all rounds and average was higher in Cr+SB than PL and CO (P <0.05) after supplementation. MP in the post‐test of Cr+SB in round 1 was higher than PL and CO (P<0.05). MP in rounds 2 and 3 and an average of rounds was higher in Cr+SB than Cr, PL, and CO. MP was higher in the post‐test of rounds 2 and 3 and an average of rounds compared to PL (P<0.05). Upon supplementation, an average FI in all rounds was less in SB than Cr (P<0.05). BL levels were higher immediately after TAIKT compared to resting levels in both pre‐ and‐post‐ingestion. BL was higher 3min after TAIKT compared to the resting level in both pre‐ and‐post‐ingestion. Three minutes after TAIKT, the BL level was lower than the level immediately after TAIKT in both pre‐ and post‐ingestion. After receiving the supplement, BL immediately and 3min after 3 rounds of TAIKT was lower in Cr+SB and SB compared to Cr, PL, and CO (P<0.05). RPE values were higher after rounds 2 and 3 compared to round 1 and were higher after round 3 than round 2, in pre‐ and post‐ingestion. In round 1, RPE decreased in Cr+SB, Cr, and SB (P<0.05) compared to PL after supplementation. In rounds 2 and 3, RPE was lower compared in Cr+SB, Cr, and SB to PL and CO (P<0.05).CONCLUSIONCo‐ingestion of Cr and SB further improved MP and PP, followed by TAIKT compared to Cr and SB ingestion alone. Cr and SB co‐ingestion and Cr alone cannot improve FIs in TAIKT, but SB alone may have a positive effect. Also, the FI in SB and Cr and SB co‐ingestion was lower than that of other groups.