Acute and chronic safety and efficacy of dose dependent creatine nitrate supplementation and exercise performance

Background: creatine monohydrate (crm) and nitrate are popular supplements for improving exercise performance; yet have not been investigated in combination. we performed two studies to determine the safety and exercise performance-characteristics of creatine nitrate (crn) supplementation. methods: study 1 participants (n = 13) ingested 1.5 g crn (crn-low),3 g crn (crn-high),5 g crm or a placebo in a randomized,crossover study (7d washout) to determine supplement safety (hepatorenal and muscle enzymes,heart rate,blood pressure and side effects) measured at time-0 (unsupplemented),30-min,and then hourly for 5-h post-ingestion. study 2 participants (n = 48) received the same crn treatments vs. 3 g crm in a randomized,double-blind,28d trial inclusive of a 7-d interim testing period and loading sequence (4 servings/d). day-7 and d-28 measured tendo™ bench press performance,wingate testing and a 6x6-s bicycle ergometer sprint. data were analyzed using a glm and results are reported as mean ± sd or mean change ± 95 % ci. results: in both studies we observed several significant,yet stochastic changes in blood markers that were not indicative of potential harm or consistent for any treatment group. equally,all treatment groups reported a similar number of minimal side effects. in study 2,there was a significant increase in plasma nitrates for both crn groups by d-7,subsequently abating by d-28. muscle creatine increased significantly by d-7 in the crm and crn-high groups,but then decreased by d-28 for crn-high. by d-28,there were significant increases in bench press lifting volume (kg) for all groups (pla,126.6,95 % ci 26.3,226.8; crm,194.1,95 % ci 89.0,299.2; crn-low,118.3,95 % ci 26.1,210.5; crn-high,267.2,95 % ci 175.0,359.4,kg). only the crn-high group was significantly greater than pla (p < 0.05). similar findings were observed for bench press peak power (pla,59.0,95 % ci 4.5,113.4; crm,68.6,95 % ci 11.4,125.8; crn-low,40.9,95 % ci -9.2,91.0; crn-high,60.9,95 % ci 10.8,111.1,w) and average power. conclusions: creatine nitrate delivered at 3 g was well-tolerated,demonstrated similar performance benefits to 3 g crm,in addition,within the confines of this study,there were no safety concerns. © 2016 galvan et al.