(961.5) Effects of Creatine Nitrate and Caffeine Alone and Co-ingested on Anaerobic and Muscular Endurance Performance

Poster Board Number: E631

Majid Koozehchian (Jacksonville State University), Gina Mabrey (Jacksonville State University), Andrew Newton (Jacksonville State University), Scott Forbes (Brandon University), Alireza Naderi (Islamic Azad University), Monoem Haddad (Qatar University)

Background: Ingestion of creatine nitrate and caffeine individually improve anaerobic and muscular endurance performance; however, co-ingestion of creatine nitrate and caffeine remains unclear.

Methods: In a double-blind, randomized, placebo-controlled cross over study, 12 resistance-trained participants (22±1 y; 180.0±9.5 cm; 85.9±15.1 kg) completed 4 conditions in random order: creatine nitrate (CN: 5 g/day + 0.675 g/day of maltodextrin), caffeine (CAF: 400 mg/day + 5 g/day of maltodextrin), CN+CAF (5 g/day of creatine nitrate + 400 mg/day of caffeine), and placebo (PL: 5.4 g/day of maltodextrin). Supplements were ingested for 7 days with a 7-day washout period between conditions. Before and after supplementation, muscular endurance (bench press and leg press; 3 sets at 70% 1RM) and a Wingate anaerobic test were performed. Peak power (PP), mean power (MP), and fatigue index (FI) were calculated. Data were analyzed using a two-way (within-within) analysis of variance (p≤0.05) with a Tukey’s post hoc when appropriate. Absolute change (post minus pre-testing) was calculated and analyzed with a repeated-measures ANOVA.

Results: There was a significant main effect of time for both leg press (p=0.009) and bench press (plt;0.001) with post-testing greater than pre-testing; however, there were no differences between conditions. For peak power, there was no significant interaction (p=0.436), the main effect of time (p=0.967), or differences between conditions for absolute change (p=0.436). For mean power, there was a significant interaction (p=0.037); however, post hoc analysis revealed no significant pairwise effects; however, absolute change for mean power between conditions was significant (p=0.037), with post hoc analysis revealing a trend (plt;0.10) for both CN conditions (CN alone and CN+CAF) to be superior compared to CAF.  There were no significant differences between conditions or overtime for fatigue index.

Conclusion: Short-term CN and CAF ingested either individually, or co-ingested could not augment upper or lower body muscular endurance or anaerobic performance compared to PL in resistance-trained participants.