Creatine supplementation and athletic performance

The Effect of Creatine Nitrate and Caffeine Individually or Combined on Exercise Performance and Cognitive Function: A Randomized, Crossover, Double-Blind, Placebo-Controlled Trial

This study examined the effect of creatine nitrate and caffeine alone and combined on exercise performance and cognitive function in resistance-trained athletes. In a double-blind, randomized crossover trial, twelve resistance-trained male athletes were supplemented with 7 days of creatine nitrate (5 g/day), caffeine (400 mg/day), and a combination of creatine nitrate and caffeine. The study involved twelve resistance-trained male athletes who initially provided a blood sample for comprehensive safety analysis, including tests for key enzymes and a lipid profile, and then performed standardized resistance exercises-bench and leg press at 70% 1RM-and a Wingate anaerobic power test. Cognitive function and cardiovascular responses were also examined forty-five minutes after supplementation. Creatine nitrate and caffeine that were co-ingested significantly enhanced cognitive function, as indicated by improved scores in the Stroop Word-Color Interference test (p = 0.04; effect size = 0.163). Co-ingestion was more effective than caffeine alone in enhancing cognitive performance. In contrast, no significant enhancements in exercise performance were observed. The co-ingestion of creatine nitrate and caffeine improved cognitive function, particularly in cognitive interference tasks, without altering short-term exercise performance. Furthermore, no adverse events were reported. Overall, the co-ingestion of creatine nitrate and caffeine appears to enhance cognition without any reported side effects for up to seven days.

Stabilization Effects Induced by Trehalose on Creatine Aqueous Solutions Investigated by Infrared Spectroscopy

Creatine is a very popular amino acid widely utilized in the sports world due to its functions mainly related to muscle building and increasing performance. The present work investigates the behavior of creatine aqueous solutions and of creatine aqueous in the presence of trehalose as a function of time changes by means of Infrared spectroscopy. Infrared spectra have been gathered and studied over time for both the full spectrum and the intramolecular OH-stretching region for the two mixtures. This latter region was studied more specifically using a cutting-edge technique called Spectral Distance (SD). From this analysis of the spectral features of the investigated samples, it emerges that trehalose has a significant stabilizing effect on creatine aqueous solutions.

The Paradoxical Effect of Creatine Monohydrate on Muscle Damage Markers: A Systematic Review and Meta-Analysis

Background

Several studies have examined the effect of creatine monohydrate (CrM) on indirect muscle damage markers and muscle performance, although pooled data from several studies indicate that the benefits of CrM on recovery dynamics are limited.

Objective

This systematic review and meta-analysis determined whether the ergogenic effects of CrM ameliorated markers of muscle damage and performance following muscle-damaging exercises.

Methods

In total, 23 studies were included, consisting of 240 participants in the CrM group (age 23.9 ± 10.4 years, height 178 ± 5 cm, body mass 76.9 ± 7.6 kg, females 10.4%) and 229 participants in the placebo group (age 23.7 ± 8.5 years, height 177 ± 5 cm, body mass 77.0 ± 6.6 kg, females 10.0%). These studies were rated as fair to excellent following the PEDro scale. The outcome measures were compared between the CrM and placebo groups at 24–36 h and 48–90 h following muscle-damaging exercises, using standardised mean differences (SMDs) and associated p-values via forest plots. Furthermore, sub-group analyses were conducted by separating studies into those that examined the effects of CrM as an acute training response (i.e., after one muscle-damaging exercise bout) and those that examined the chronic training response (i.e., examining the acute response after the last training session following several weeks of training).

Results

According to the meta-analysis, the CrM group exhibited significantly lower indirect muscle damage markers (i.e., creatine kinase, lactate dehydrogenase, and/or myoglobin) at 48–90 h post-exercise for the acute training response (SMD − 1.09; p = 0.03). However, indirect muscle damage markers were significantly greater in the CrM group at 24 h post-exercise (SMD 0.95; p = 0.04) for the chronic training response. Although not significant, a large difference in indirect muscle damage markers was also found at 48 h post-exercise (SMD 1.24) for the chronic training response. The CrM group also showed lower inflammation for the acute training response at 24–36 h post-exercise and 48–90 h post-exercise with a large effect size (SMD − 1.38 ≤ d ≤  − 1.79). Similarly, the oxidative stress markers were lower for the acute training response in the CrM group at 24–36 h post-exercise and 90 h post-exercise, with a large effect size (SMD − 1.37 and − 1.36, respectively). For delayed-onset muscle soreness (DOMS), the measures were lower for the CrM group at 24 h post-exercise with a moderate effect size (SMD − 0.66) as an acute training response. However, the inter-group differences for inflammation, oxidative stress, and DOMS were not statistically significant (p > 0.05).

Conclusion

Overall, our meta-analysis demonstrated a paradoxical effect of CrM supplementation post-exercise, where CrM appears to minimise exercise-induced muscle damage as an acute training response, although this trend is reversed as a chronic training response. Thus, CrM may be effective in reducing the level of exercise-induced muscle damage following a single bout of strenuous exercises, although training-induced stress could be exacerbated following long-term supplementation of CrM. Although long-term usage of CrM is known to enhance training adaptations, whether the increased level of exercise-induced muscle damage as a chronic training response may provide potential mechanisms to enhance chronic training adaptations with CrM supplementation remains to be confirmed.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-022-01640-z.

Chronic Dialysis Patients Are Depleted of Creatine: Review and Rationale for Intradialytic Creatine Supplementation

There is great need for the identification of new, potentially modifiable risk factors for the poor health-related quality of life (HRQoL) and of the excess risk of mortality in dialysis-dependent chronic kidney disease patients. Creatine is an essential contributor to cellular energy homeostasis, yet, on a daily basis, 1.6–1.7% of the total creatine pool is non-enzymatically degraded to creatinine and subsequently lost via urinary excretion, thereby necessitating a continuous supply of new creatine in order to remain in steady-state. Because of an insufficient ability to synthesize creatine, unopposed losses to the dialysis fluid, and insufficient intake due to dietary recommendations that are increasingly steered towards more plant-based diets, hemodialysis patients are prone to creatine deficiency, and may benefit from creatine supplementation. To avoid problems with compliance and fluid balance, and, furthermore, to prevent intradialytic losses of creatine to the dialysate, we aim to investigate the potential of intradialytic creatine supplementation in improving outcomes. Given the known physiological effects of creatine, intradialytic creatine supplementation may help to maintain creatine homeostasis among dialysis-dependent chronic kidney disease patients, and consequently improve muscle status, nutritional status, neurocognitive status, HRQoL. Additionally, we describe the rationale and design for a block-randomized, double-blind, placebo-controlled pilot study. The aim of the pilot study is to explore the creatine uptake in the circulation and tissues following different creatine supplementation dosages.

Supplementation with a proprietary blend of ancient peat and apple extract may improve body composition without affecting hematology in resistance-trained men

Adenosine-5'-triphosphate (ATP) is primarily known as a cellular source of energy. Increased ATP levels may have the potential to enhance body composition. A novel, proprietary blend of ancient peat and apple extracts has been reported to increase ATP levels, potentially by enhancing mitochondrial ATP production. Therefore, the purpose of this investigation was to determine the supplement's effects on body composition when consumed during 12 weeks of resistance training. Twenty-five healthy, resistance-trained, male subjects (age, 27.7 ± 4.8 years; height, 176.0 ± 6.5 cm; body mass, 83.2 ± 12.1 kg) completed this study. Subjects supplemented once daily with either 1 serving (150 mg) of a proprietary blend of ancient peat and apple extracts (TRT) or placebo (PLA). Supervised resistance training consisted of 8 weeks of daily undulating periodized training followed by a 2-week overreach and a 2-week taper phase. Body composition was assessed using dual-energy X-ray absorptiometry and ultrasound at weeks 0, 4, 8, 10, and 12. Vital signs and blood markers were assessed at weeks 0, 8, and 12. Significant group × time (p < 0.05) interactions were present for ultrasound-determined cross-sectional area, which increased in TRT (+0.91 cm(2)) versus PLA (-0.08 cm(2)), as well as muscle thickness (TRT: +0.46; PLA: +0.04 cm). A significant group × time (p < 0.05) interaction existed for creatinine (TRT: +0.06; PLA: +0.15 mg/dL), triglycerides (TRT: +24.1; PLA: -20.2 mg/dL), and very-low-density lipoprotein (TRT: +4.9; PLA: -3.9 mg/dL), which remained within clinical ranges. Supplementation with a proprietary blend of ancient peat and apple extracts may enhance resistance training-induced skeletal muscle hypertrophy without affecting fat mass or blood chemistry in healthy males.

Disorders of Fuel Metabolism: Medical Complications Associated with Starvation, Eating Disorders, Dietary Fads, and Supplements

Disorders of fuel metabolism as they relate to abnormal fuel intake,abnormal fuel expenditure, and dietary supplements are the focus of this article. The emergency physician should be aware of the medical complications that can occur as a result of starvation states,eating disorders, fad diets, hypermetabolic states, and ergogenic aids. Knowledge and understanding of the complications associated with these disorders will facilitate the diagnosis and management of patients who present to the emergency department with any of the disorders reviewed.