Effects of glucuronolactone and the other carbohydrates on the biochemical changes produced in the living body of rats by hard exercise

The Dark Side of Energy Drinks: A Comprehensive Review of Their Impact on the Human Body

In recent years, the consumption of energy drinks by young adults and athletes has risen significantly, but concerns have been raised about the potential health risks associated with excessive consumption. These concerns include cardiovascular problems, nervous system disorders, and the potential for addiction. This review aims to examine the reported effects of acute or chronic abuse of energy drinks on human health. The analysis shows a significant prevalence of adverse effects, particularly on the cardiovascular and neurovegetative systems. In particular, the analysis identified nine cases of cardiac arrest, three of which were fatal. The aetiology of these adverse effects is attributed to the inherent neurostimulant properties of these beverages, of which caffeine is the predominant component. A comparison of documented effects in humans with experimental studies in animal models showed an overlap in results. This review highlights the need for greater rigour in the assessment of sudden cardiac death, particularly in young people, as legal substances such as energy drinks may be involved. We propose stricter limits on the consumption of these beverages than for caffeine, based on the evidence found and the data in the literature. This review also calls for the establishment of regulations governing the consumption of these products in view of their potential impact on human health.

Risk assessment of energy drinks with focus on cardiovascular parameters and energy drink consumption in Europe

To assess the possible cardiovascular risks associated with energy drink (ED) consumption in Europe, a comprehensive literature research was performed in regard to (i) possible ED-induced dose-dependent cardiovascular outcomes, (ii) ED consumption patterns in Europe and (iii) the risks of EDs in combination with alcohol. The identified intervention studies primarily investigated acute ED effects in young healthy adults. Moderate consumption of EDs corresponding to an acute caffeine intake of up to 200 mg did not result in clinically relevant cardiovascular changes in young healthy adults. However, high intake of EDs (about 1 L) was associated with moderate to severe adverse effects in some participants (i.a. prolonged QTc interval, palpitations). Studies have indicated that on some occasions, a substantial proportion of ED consuming children and adolescents (12% in 16 EU Member States) drink EDs in high quantities (≥1 L). This could pose a possible health risk to this group since adverse effects by such high ED consumption have been observed already in young healthy adults. Among further measures that might be considered to minimize this identified risk, policy makers could develop information and educational programs with the aim of raising public awareness.

Effects of energy drinks on the cardiovascular system

Throughout the last decade, the use of energy drinks has been increasingly looked upon with caution as potentially dangerous due to their perceived strong concentration of caffeine aside from other substances such as taurine, guarana, and L-carnitine that are largely unknown to the general public. In addition, a large number of energy drink intoxications have been reported all over the world including cases of seizures and arrhythmias. In this paper, we focus on the effect of energy drinks on the cardiovascular system and whether the current ongoing call for the products' sales and regulation of their contents should continue.

Arrhythmogenic effects of energy drinks

Energy drinks (ED) are increasingly popular, especially among adolescents and young adults. They are marketed as enhancers of energy, alertness, and physical performance. ED contain high doses of caffeine and other active ingredients. Their safety has come under question due to reports temporally linking ED consumption with serious cardiovascular events, including arrhythmias and sudden cardiac death. In this article, we report 2 cases of life-threatening ventricular arrhythmias in young patients after consuming ED. We also review the ingredients of ED, the physiologic effects on the cardiovascular system, and the available evidence suggesting arrhythmogenecity.

The effect of acute pre-workout supplementation on power and strength performance

BACKGROUND

Consumption of pre-workout dietary supplements by both recreational and competitive athletes has increased dramatically in recent years. The purpose of this study was to determine the acute effects of a caffeine-containing pre-workout dietary supplement on various measures of performance including anaerobic power, upper and lower body power, and upper body strength in recreationally trained males.

METHODS

Thirteen males (mean ± SD age = 24 ± 6 yrs; height = 180.3 ± 5 cm; body mass = 83.4 ± 9 kg) participated in this investigation in which they reported to the laboratory on four separate occasions, each separated by one week. Each subject underwent an initial familiarization session on week one followed by baseline (BA) performance testing on week two. Performance testing included a medicine ball put (MBP) to determine upper body explosive power, vertical jump test (VJ) to determine lower body explosive power, one-rep maximum bench press (1-RM) for determining upper body strength, and a Wingate Anaerobic Power Test (WAnT) to determine measures of anaerobic power. On week three, subjects were randomly assigned to ingest either a pre-workout supplement (SUP) or a placebo (PL) and again complete the performance testing protocol. Subjects were provided with the crossover treatment on the fourth and final week. Performance testing commenced 20-minute following ingestion of both treatments, which was similar to previous investigations.

RESULTS

Significant differences in anaerobic peak power relative to the WAnT were observed following ingestion of the SUP (782 ± 191 W) in comparison to the PL (722 ± 208 W; p = 0.003; effect size = 0.30) and BA (723 ± 205 W; p = 0.011; effect size = 0.28). Significant differences were also observed for anaerobic mean power following ingestion of the SUP (569 ± 133 W) in comparison to the PL (535 ± 149 W; p = 0.006; effect size = 0.24) and BA (538 ± 148 W; p = 0.020; effect size = 0.22). No significant differences between trials were observed for upper body power, lower body power, or upper body strength.

CONCLUSIONS

Ingestion of the pre-workout dietary supplement led to significant improvements in anaerobic peak and mean power values in comparison to the placebo and baseline treatments. No improvements were observed in upper and lower body power or upper body strength. Taken prior to exercise, a caffeine-containing pre-workout dietary supplement may improve anaerobic power performance.

The thermic effect of sugar-free Red Bull: do the non-caffeine bioactive ingredients in energy drinks play a role?

OBJECTIVE

Consumption of energy drinks is increasing amongst athletes and the general public. By virtue of their bioactive ingredients (including caffeine, taurine, glucuronolactone, and B-group vitamins) and paucity of calories, sugar-free "diet" versions of these drinks could be a useful aid for weight maintenance. Yet little is known about the acute influence of these drinks, and specifically the role of the cocktail of non-caffeine ingredients, on resting energy expenditure (REE) and substrate oxidation. Therefore, the metabolic impact of sugar-free Red Bull (sfRB) to a comparable amount of caffeine was compared.

METHODS

REE and respiratory quotient (RQ) were measured in eight healthy young men by ventilated-hood indirect calorimetry for 30 min baseline and 2 h following ingestion of 355 ml of either: sfRB + placebo, water + 120 mg caffeine, or water + placebo, according to a randomized cross-over design.

RESULTS

sfRB and water + caffeine both increased REE to the same degree (+4%). Additionally, sfRB briefly increased RQ. Water + caffeine had no effect on RQ relative to water + placebo.

CONCLUSIONS

sfRB enhanced thermogenesis and marginally shifted RQ to favor carbohydrate oxidation. The stimulatory effects of sfRB on REE are mimicked by water + caffeine, indicating that the auxiliary ingredients do not influence this thermic effect. The metabolic effects of sfRB are primarily due to caffeine alone.

Metabolic adaptations in the liver of born long-distance running mice

PURPOSE

Long-distance runners have increased needs of energy supply. To unravel genetically based mechanisms required for efficient energy supply, we have analyzed hepatic metabolism of mice characterized by the inborn capacity to perform as long-distance runners.

METHODS

The mouse model had been established by phenotypic selection for high treadmill performance for 90 generations and was characterized by approximately 3.8-fold higher running capacities (Dummerstorf high Treadmill Performance mouse line [DUhTP]) compared with unselected and also untrained controls (Dummerstorf Control mouse line [DUC]). From 7-wk-old male mice, serum and liver samples were collected and analyzed for messenger RNA, protein, and metabolite levels, respectively.

RESULTS

In livers from DUhTP mice, we identified significantly higher messenger RNA transcript levels of peroxisome proliferator-activated receptor delta and higher protein levels of sirtuin-1, acetyl-CoA-synthetase, acetyl-CoA-carboxylase, phosphoenolpyruvate carboxykinase, and glutamate-dehydrogenase, suggesting higher gluconeogenesis and lipogenesis in DUhTP mice. In fact, higher hepatic levels of glycogen and triglycerides as well as higher concentrations of carbohydrate, fatty acid, and cholesterol metabolites were found in DUhTP mice. In parallel, in DUhTP mice, which did not have access to running wheels, a marked hyperlipidemia (cholesterol = 160% ± 8%, triglycerides = 174% ± 14% of controls, respectively), and abdominal obesity (DUhTP = 0.396 ± 0.019 g, DUC = 0.291 ± 0.019 g) were found.

CONCLUSIONS

From our data, we conclude that the physiological basis of genetically fixed higher endurance-running performance in DUhTP marathon mouse is related to increased hepatic gluconeogenesis and lipogenesis. Expression of sirtuin 1 as well as of gluconeogenic and lipogenic key enzymes may be related to peroxisome proliferator-activated receptor delta. Metabolic adaptations presented in our study represent inborn features of superior endurance-running performance.