Acute and chronic safety and efficacy of dose dependent creatine nitrate supplementation and exercise performance.
Study Goal
The researchers aimed to determine the safety and exercise performance effects of creatine nitrate (CrN) supplementation, both alone and in comparison to creatine monohydrate (CrM).
Results Summary
The study found that CrN was well-tolerated with minimal side effects and showed significant increases in bench press performance, particularly at the 3 g dosage. Plasma nitrates increased by day 7 but abated by day 28, while muscle creatine levels varied by dosage and time.
Population
Healthy participants (N=13 in Study 1, N=48 in Study 2)
Effective Dosage
1.5 g CrN (CrN-Low), 3 g CrN (CrN-High), 5 g CrM (Study 1), 3 g CrM (Study 2)
Duration
Study 1: Single dose with 5-hour monitoring; Study 2: 28-day trial with interim testing at day 7
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
creatine nitrate (CrN) supplementation | no change | blood markers | participants (N=13) | not indicative of potential harm or consistent for any treatment group | observed several significant, yet stochastic changes | #1 |
all treatment groups | no change | minimal side effects | participants (N=13) | similar number | reported a similar number | #2 |
CrN groups | increase | plasma nitrates | participants (N=48) | by d-7 | significant increase | #3 |
CrN groups | decrease | plasma nitrates | participants (N=48) | by d-28 | abating | #4 |
CrM and CrN-High groups | increase | muscle creatine | participants (N=48) | by d-7 | increased significantly | #5 |
CrN-High group | decrease | muscle creatine | participants (N=48) | by d-28 | decreased | #6 |
all groups | increase | bench press lifting volume (kg) | participants (N=48) | by d-28 | significant increases | #7 |
CrN-High group | increase | bench press lifting volume | participants (N=48) | p < 0.05 | significantly greater than PLA | #8 |
creatine nitrate delivered at 3 g | no change | tolerance | participants | - | well-tolerated | #9 |
creatine nitrate delivered at 3 g | no change | performance benefits | participants | similar | demonstrated similar performance benefits to 3 g CrM | #10 |
creatine nitrate | no change | safety | participants | no safety concerns | there were no safety concerns | #11 |
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.