Effect of Red Bull Energy Drink

International Journal of brag Nutrition and Exercise Metabolism,? cc7,? 17,? 433-444? ? cc7? gentlemans gentleman? Kinetics,? Inc. takings of departure cop Energy Drink on reiterate Wingate Cycle Performance and Bench-Press Muscle Endurance Scott C. Forbes, Darren G. Candow, Jonathan P. Little, Charlene Magnus, and Philip D. Chilibeck The purpose of this take away was to doctor the marrows of reddish bull finished muscularity fuddle on Wingate musical rhythm surgery and muscle resolution. healthy childlike adults (N = 15, 11 men, 4 women, 21 5 y old) participated in a cross all over analyse in which they were randomised to accompaniment with cherry-red red cent (2 mg/kg clay troop of caffein) or isoenergetic, isovolumetric, noncaffeinated placebo, illogical by 7 d. Muscle endurance (bench press) was treasureed by the supreme number of repetitions over 3 assembles (separated by 1-mo minuteistration intervals) at an intensity corresponding to 70% of se rv frost line 1-repetition maximum. Three 30-s Wingate cycle discharges (load = 0. 075 kp/kg body crowd together), with 2 min recupe symmetryn betwixt tests, were use to assess hint and clean place rig. florid bull readiness potable importantly increase perfect bench-press repetitions over 3 rigids ( chromatic hair = 34 9 vs. placebo = 32 8, P 0. 05) exclusively had no nitty-gritty on Wingate superlative or honest place ( departure hog = 701 124 W vs. placebo = 700 132 W, blushful Bull = 479 74 W vs. placebo = 471 74 W, respectively). loss Bull energy absorb significantly change magnitude f number berth berth body muscle endurance scarce had no stamp on an oxidative peak or average power during restate Wingate cycling tests in young healthy adults. lynchpin Words anaerobic power, caffein, exertion Red Bull energy imbibition is purported to improve some aspects of execution of instrument (i. . , re characterizationion season, denseness, and alertness) in exercising individuals (1). The base ergogenic factor in Red Bull is caffein. Acute caffein uptake of 29 mg/kg body weight during aerobic praxis increases endurance and reduces dull (11, 12, 25, 37, 46). Most interrogation on caffein breathing in has foc apply primarily on its effect during short-term or extended aerobic influence (23), with numerous studies supporting an ergogenic effect from caffein on perform time to exhaustion (17, 22, 29, 46, 48), maximal power output (32, 37), and exertion time (9, 41).The effects of caffein wasting disease on anaerobic deed (i. e. , Wingate cycle power) and muscle endurance Forbes, Little, Magnus, and Chilibeck atomic number 18 with the College of Kinesiology, University of Saskatchewan, Saskatoon, SK, Canada S7N 5B2. Candow is with the Faculty of Kinesiology and health Studies, University of Regina, Regina, SK, Canada S4S 0A2. ? ? 433 434 Forbes? et? al. (i. e. , total repetitions for lifting a presumptio n resistance over multiple sets) are less evident, however. Regarding anaerobic public presentation, Collump et al. 16) showed that caffeine ingestion (250 mg) 1 h ahead 100-m freestyle swimming significantly improved writ of execution time. In addition, caffeine ingestion (250 mg) 30 min sooner reading resulted in significant emoluments during a maximum-power 6-s cycle sprint against various loads (2). Greer et al. (28), however, observed no improvement in maximum force output or reduced fatigue during repeated Wingate anaerobic tests with 6 mg/kg of caffeine 1 h out front cause Collomp et al. (15) fix no improvement during a wizard 30-s Wingate test with 5 mg/kg of caffeine 60 min forward exercise and Crowe et al. 18) found that 6 mg/kg of caffeine given 90 min before two 60-s cycling bouts had no effect on peak power or hold output. Regarding muscle endurance, Kalmar and Cafarelli (35) describe that 6 mg/kg of caffeine given 1 h before exercise significantly increase d submaximal isometric-contraction time. In contrast, Beck et al. (7) and Jacobs et al. (34) found no improvement in bench-press or leg-press muscle endurance (i. e. , total repetitions of lifting a weight corresponding to 7080% one-repetition maximum 1-RM) 6090 min aft(prenominal)wardsward subordinates consumed 2. 54 mg/kg of caffeine.Although it is difficult to compare results across studies, possible explanations for these inconsistent findings index include the dose of caffeine used, capacity training status, timing of caffeine ingestion, customary caffeine employment, and exercise modality. Although the mechanisms explaining the possible ergogenic effects of caffeine tarry to be elucidated, plausible theories include caffeines ability to act as an adenosine-receptor antagonist (18, 19, 23), increase plasma epinephrine concentrations (33, 45), enhance atomic number 20 release and reuptake from the arcoplasmic reticulum (40), and alter plasma special K concentrations (18). These mechanisms almost likely occur with larger caffeine doses, and it is unclear whether smaller doses would be as effective. Recently it was found that larger doses of caffeine readiness restrain negative health consequences such as impaired glucose tolerance (6). We and so decided to study the effects of a smaller dose of caffeine (2 mg/kg) in the form of Red Bull energy present. To date, that 1 study has examined the effects of Red Bull energy drink on anaerobic exercise performance in young adults.Alford et al. (1) found a significant increase in maximum speed during an complete cycling test after Red Bull accessory (80 mg caffeine). Our purpose was to run into the effects of Red Bull energy drink on a more stockized test of anaerobic performance (i. e. , Wingate cycle test) and on muscle endurance (i. e. , maximal repetitions during bench-press lifting). These tests were used to mold the demands of blows such as methamphetamine hockey that involve repeated bursts of activity or muscle endurance of both the cut and pep pill body.Energy-drink consumption and caffeine auxiliaryation are very common in this image of sport (38). We hypothesized that Red Bull supplementation would increase Wingate anaerobic peak and average power and bench-press muscle endurance. Methods Participants Sixteen healthy somatogenicly alert participants (12 men, 4 women, 24 6 y old) volunteered for the study. They participated in moderate physical activity 2 or 3 Effect? of? Red? Bull? on? acrobatic? Performance? ? 435 generation per week and were instructed non to shift their diets or physical activity patterns before or during the study.All subjects were required to pick out out a Physical Activity Readiness Questionnaire, which screens for health problems that major power present a risk with performance of physical activity (52). The study was approved by the University of Saskatchewan Biomedical Research Ethics Board for research in human subje cts. Participants were informed of the risks and purposes of the study before they gave their written consent. data-based Design The study used a double-blind repeated-measures crossover counterbalanced picture in which participants were randomized to supplement with Red Bull or placebo and find out the contrary treatment 7 d later.All participants were required to come to the science laboratory on 2 occasions before the start of the study, once to determine their bench-press 1-RM strength and again 3 d later for familiarization with the experimental foundation by performing 3 sets of bench-press repetitions to fatigue (separated by 1-min rest intervals) at an intensity corresponding to 70% 1-RM, followed by three 30-s Wingate cycle tests (separated by 2-min rest intervals) at a load corresponding to 0. 075 kp/kg body mass (4). There was a 10-min rest period surrounded by the bench-press endurance tests and Wingate cycle tests.Three days after the familiarization examination, subjects were randomly assigned to supplement with Red Bull (2. 0 mg/kg caffeine) or placebo (noncaffeinated Mountain Dew, rotter juice, water) 60 min before performing repeated-bench-press endurance tests and Wingate cycle tests. vii days after this initial supplementation and testing session, subjects returned to the laboratory and ingested the opposite supplement drink and performed the same exercises in the same order. They were instructed to refrain from caffeine for 48 h, physical activity for 24 h, and food and drink for 3 h before testing.The 7-d counterbalance was chosen to allow subjects adequate recovery between exercise tests. The 48 h of caffeine withdrawal before testing would be adequate because the half-life of caffeine is about 46 h (24). The dependent variables heedful were bench-press endurance, peak power during repeated Wingate tests, and average power over 3 Wingate tests. Physical activity direct and habitual caffeine consumption were recorded before the study by means of the questionnaire. The exercise tests were chosen to simulate sports that involve repeated bursts of lavishly-intensity activity, such as ice hockey.For example, the 30-s Wingate tests with 2 min rest between tests simulate the lock-to-rest ratio of typical hockey shifts. Timemotion analyses indicate skating times of 3040 s between rest intervals of either babble out stops or time on the bench. Whistle stops farthermost about 27 s, whereas time on the bench is about 227 s, for an average rest interval of about 2 min (27, 47). The bench-press test simulates upper body model during ice hockey, such as occurs during corner play and occasionally fighting (26).A caffeine-containing supplement is ideal to evaluate for this type of sport because caffeine-containing supplements are the most popular type of supplement ingested by ice hockey players (38). 436 Forbes? et? al. Supplementation Red Bull and the placebo were identical in thermal content, volume, and taste . Supplements were provided to each participant 60 min before exercise in an opaque water bottle and consumed in the presence of a researcher. lux minutes was chosen because this is the approximate time it takes for caffeine concentration to penetrate its peak after oral ingestion (23). The caffeine dose of 2. mg/kg was chosen because it is an approximate amount shown to increase muscle performance (7) and reduce fatigue in young healthy adults, high doses might be associated with impaired glucose tolerance (6), it is the maximal daily dose of mercantile energy drinks considered safe by Health Canada (30), and this dose allowed our heaviest subjects to consume some 2 cans of Red Bull, which is the maximal amount recommended on the Red Bull label. chemical elements in the Red Bull energy drink are shown in add-in 1. Muscle Strength and Endurance The procedures for determining bench-press 1-RM have previously been described (13).All bench-press testing was done on a bench-press machine (Lever chest-press machine, Winnipeg, MB, Canada). reproducibility of our 1-RM test, expressed as a coefficient of variation, was 1. 9% (14). For bench-press muscle endurance, participants performed 3 sets of bench-press repetitions to volitional fatigue, separated by 1-min rest intervals, at an intensity corresponding to 70% 1-RM. duplicability of the bench-press endurance test was assessed by testing 15 subjects 3 d apart. The coefficient of variation was 1. 5%. Anaerobic Power tip power and average power were assessed using repeated Wingate cycleergometer tests. line of reasoning nurse concentration was measured at rest, immediately after each Wingate cycle test, and 2 min postexercise using an automated lactate analyzer (Accutrend Lactate, Roche Diagnostics, Mannheim, Germany) according to the manufacturers instructions. Ten minutes after the bench-press endurance test, each subject was positioned on the Wingate cycle ergometer, and seat height, handlebar Table 1 Re d Bull Energy-Drink Ingredients Ingredient Sugar caffeine Taurine Glucuronolactone Niacin Pantothenic acid Vitamin B6 Riboflavin Vitamin B12 total (per kg body mass) 0. 65 g/kg 2. 0 mg/kg 25 mg/kg 15 mg/kg 0. 45 mg/kg 0. 15 mg/kg 0. 5 mg/kg 0. 04 mg/kg 0. 025 g/kg Effect? of? Red? Bull? on? Athletic? Performance? ? 437 height and position, and walk straps were adjusted based on the settings determined during the familiarization trial. Subjects were instructed to cycle at a slow pace against zero resistance for 5 min. Five seconds before data collection, they were instructed to pedal at maximal rate to ensure optimal power and force production at the beginning of the test and to come up cycling at a maximal speed for the duration of the 30-s test at a load corresponding to 7. 5% of their body mass (4). Subjects were verbally encouraged throughout the test.This procedure was repeated for 3 tests, with 2 min of vigorous rest against zero load between tests. Reproducibility of peak and average power was determined by testing 10 subjects 3 d apart. The coefficients of variation were 4. 1% for peak power and 3. 6% for average power. statistical Analyses A 2 (caffeine- consume subjects vs. caffeine-naive subjects) ? 2 (supplement Red Bull vs. placebo) ? 3 (exercise sets) ANOVA with repeated measures on the last 2 factors was used to assess differences between judicial admissions for benchpress repetitions and for peak and average power during the Wingate tests. A 2 (caffeine-consuming subjects vs. affeine naive subjects) ? 2 (supplement Red Bull vs. placebo) ? 5 ( occupation lactate at 5 time points) ANOVA with repeated measures on the last 2 factors was used to assess changes in dividing line lactate concentration. To determine whether 1 familiarization trial was adequate to eliminate any effects of learning over time, we ran a 3 (set) ? 2 (time) repeatedmeasures ANOVA to determine whether there were differences across sets for Wingate tests and bench-press tests between the familiarization and placebo trials. Tukeys post hoc tests were used to determine differences between means. Statistical significance was set at P ? 0. 05.All results are expressed as mean standard deviation. Statistical analyses were carried out using Statistica, version 5. 0 (StatsSoft Inc. , Chicago). Results Of the original 16 subjects who volunteered, 15 completed the study. One male subject withdrew because of time constraints. Seven subjects were correct in perceiving that they were ingesting Red Bull or placebo, with the re of importing subjects unsure. Before testing, 8 subjects were caffeine naive, 4 reported consuming 200 mg/d. There were no side effects reported from the exercise testing, Red Bull energy drink, or placebo.There were no time important effects or set ? time interactions between the familiarization trial and the placebo trial, indicating that the familiarization trial was adequate to eliminate any learning effects. Subjects who regularly consumed caffeine did not differ from caffeine-naive subjects for any of the tests or for their receptions to Red Bull versus placebo (i. e. , there were no group ? supplement interactions). There was a supplement main effect for bench-press endurance, whereby the number of repetitions over the 3 sets was greater in the Red Bull condition than with placebo (Red Bull = 34 9 vs. lacebo = 32 8 repetitions over the 3 sets, P = 0. 031 epitome 1). There was a set main effect for bench-press endurance, Wingate peak power (Figure 2), and Wingate average power (Figure 3) that is, performance dropped across sets as 438 Forbes? et? al. would be expected (P 0. 05). There were no differences between Red Bull and placebo for performance across sets during the Wingate tests (peak and average power Red Bull = 701 124 W vs. placebo = 700 132 W and Red Bull = 479 74 W vs. placebo = 471 74 W), and there were no supplement ? et interactions for any of the exercise tests (Figures 2 and 3). Ther e was a time main effect for blood lactate (mmol/L) during repeated Wingate tests (P 0. 01 baseline Red Bull 4. 2 1. 3 vs. placebo 3. 6 1. 0 after test 1 Red Bull 7. 4 2. 4 vs. placebo 6. 6 1. 8 after leaven 2 Red Bull 9. 0 2. 9 vs. placebo 8. 9 3. 4 after tribulation 3 Red Bull 9. 3 4. 2 vs. placebo 8. 1 4. 7 and 2 min postexercise Red Bull 9. 2 3. 0 vs. placebo 7. 9 2. 4), with no differences between Red Bull and placebo (Figure 4). Post hoc analyses indicated that blood summation repetitions over 3 sets of bench press 5 40 35 30 25 20 15 10 5 0 Red Bull placebo * Figure 1 Bench-press repetitions across sets, mean standard deviation. Units are repetition number. Repetition number was determined as the total number of repetitions over 3 sets of bench-press exercise at 70% of 1-repetition maximum, 1 min of rest between sets. *Number of repetitions performed during the Red Bull condition was greater than the number of repetitions performed during the placebo condition (P = 0. 031). 850 Red Bull placebo Wingate peak power (W) 800 750 700 650 600 550 500 450 400 educate 1 case-hardened 2 sterilise 3 Figure 2 Wingate peak power across sets, mean standard deviation. Peak power was determined by the highest power output during each of 3 sets of 30-s Wingate tests, with 2 min of rest between tests. There were no differences between Red Bull and placebo conditions. There was a main effect for set, with decide 1 higher than Set 2 (P = 0. 021) and Set 2 higher than Set 3 (P 0. 01). Effect? of? Red? Bull? on? Athletic? Performance? ? 439 700 Wingate average power (W) 650 600 550 500 450 400 350 300 250 200 Set 1 Set 2 Red Bull placebo Set 3Figure 3 Wingate average power across sets, mean standard deviation. number power was determined during each of 3 sets of 30-s Wingate tests, with 2 min of rest between tests. There was a set main effect, with Set 1 higher than Set 2 (P 0. 01) and Set 2 higher than Set 3 (P 0. 01). 14 12 Red Bull placebo Lact ate (mMol/L) 10 8 6 4 2 0 baseline after Set 1 after Set 2 after Set 3 2 min post Figure 4 Blood lactate concentration before and after each set of 30-s Wingate tests (separated by 2 min of recovery) and 2 min postexercise, mean standard deviation.Blood lactate values were determined from fingertip blood samples. There was a set main effect for lactate (P 0. 01). Blood lactate concentration increased from baseline to after Set 1 (P 0. 01) and from after Set 1 to after Set 2 (P = 0. 016). Lactate values after Set 2 were similar to lactate values after Set 3 and 2 min after Set 3. lactate concentration was elevated higher up baseline after each Wingate test and at 2 min after the last Wingate test (all P 0. 01). Blood lactate concentration increased from baseline to after Test 1 (P 0. 01) and from after Test 1 to after Test 2 (P = 0. 16). Lactate values after Test 2 were similar those after Test 3 and 2 min after Test 3. Discussion This is the first study to inquire the effects of Red Bull energy drink on upper body muscle endurance and anaerobic cycle performance in young adults. Results 440 Forbes? et? al. showed that Red Bull energy drink significantly increased total bench-press repetitions over 3 sets compared with placebo just now had no significant effect on peak or average power or blood lactate concentration during repeated Wingate cycling tests. The main active ingredient in Red Bull energy drink is caffeine.Although the mechanisms explaining the ergogenic effects of caffeine are not fully known, plausible theories include the antagonism of adenosine receptors (18, 23, 42) direct to an increase in central-nervous-system activation (54) and plasma epinephrine concentrations (45), enhanced atomic number 20 release and reuptake from the sarcoplasmic reticulum (40) affecting skeletal-muscle excitationcontraction codt (42), and the alteration of plasma potassium concentrations (18, 39). caffeine has been shown to reduce plasma potassium levels c ompared with placebo during exercise (39).The increased intracellular potassium concentration coupled with lower extracellular potassium might help maintain membrane contractility during exercise (39). Our results of a greater increase in bench-press repetitions over 3 sets from Red Bull ingestion (2. 0 mg/kg), only when no single set effect, expand the findings of Beck et al. (7), who found no effect of a caffeine-containing supplement (2. 4 mg/kg) on single-set bench-press repetitions. For the present study, bench-press muscle endurance was assessed by the total number of repetitions over 3 sets at 70% 1-RM separated by 1-min rest intervals.In contrast, participants in the Beck et al. (7) study performed a single set of bench-press repetitions at 80% 1-RM. Differences in supplement composition, study design (crossover vs. cross-sectional), and grammatical gender might also explain these different results. In addition, we cannot conclude with sure thing that the greater increase in bench-press repetitions from Red Bull energy drink is a result solely of caffeine, because Red Bull contains other ingredients ( grab Table 1) such as carnitine, B vitamins, and taurine.The effectiveness of carnitine is controversial, with most studies showing no benefit but some showing a benefit for increased fat metabolism and enhanced recovery from exercise stress (for reviews, see 10 and 36). These ergogenic effects might help during aerobic endurance exercise however, it is doubtful that a benefit would be provided by acute supplementation before high-intensity exercise. Carnitine supplementation has no effect on high-intensity exercise performance (i. e. five 90-m swims separated by 2-min rest intervals) (53) or metabolic reaction to high-intensity exercise (i. e. , five 1-min cycle sprints separated by 2-min rest intervals) (5). The B vitamins are important for chronic adaptation to exercise training but most likely would have minimal influence when taken before an acute exercise session (55). Although carnitine and the B vitamins might not be ergogenic for the exercise tests used in the current study, taurine might face beneficial effects.Taurine, a sulfonic amino acid found primarily in skeletal muscle (31, 44), has been shown to increase force production in scramble muscle fibers in a rodent model (3), possibly through increased calcium release from the sarcoplasmic reticulum and increased calcium esthesia for excitationcontraction coupling. Others have suggested that taurine might exhibit evasive effects against cellular stress such as exercise by acting as a free-radical scavenger (49).In humans, taurine supplementation (6 g/d) significantly increased exercise time to exhaustion, VO2max, and maximal workload during cycle-ergometer exercise (56). Nonetheless, the amount of taurine administered before exercise in the current study was relatively low, ranging from 1 to 2 g. Therefore, it is doubtful that it would have significantly abnormal p erformance. Effect? of? Red? Bull? on? Athletic? Performance? ? 441 Red Bull energy drink had no effect on anaerobic power measures. These findings support those of Beck et al. 7), who found no effect from a caffeine-containing supplement on peak or average power output in young adults. Although it is unclear why these caffeine-containing supplements had no greater effect on anaerobic power output compared with the findings of others (2, 16), possible explanations might include the caffeine dose used, caffeine habituation, and individual training status. The caffeine dose used in the current study (2. 0 mg/kg) and that of Beck et al. (7) of 2. 4 mg/kg might have been too low to observe an ergogenic effect on anaerobic-power measures.Regarding caffeine habituation, most subjects in the current study were caffeine naive however, 7 of 15 subjects were caffeine users, with 4 consuming 200 mg caffeine per day. The Red Bull energy drink provided close to an additional 150 mg caffeine. On e previous study suggested that caffeine might not be ergogenic in habitual caffeine consumers as a result of caffeine saturation (50). Several studies have shown, however, that habitual caffeine intake does not affect the ergogenic benefits of caffeine (8, 20, 21, 43, 51).In agreement with these studies, we did not find any differences in response to the Red Bull energy drink between caffeineconsuming subjects and caffeine-naive subjects. Finally, in examining the effects of caffeine ingestion on anaerobic performance in trained and untrained swimmers, Collump et al. (16) observed a decrease in 100-m swim time in the trained swimmers but no effect in the untrained swimmers. We suggest that the variations in subject training status might explain the lack of consistency across studies. Most studies that report positive effects from caffeine on naerobic exercise have used well-trained subjects (16, 20). The results of the current study suggest that moderately active individuals experi ence no anaerobic benefit from caffeine through Red Bull energy-drink ingestion. In summary, the results of the present study indicate that Red Bull energy drink increases upper body muscle endurance but has no effect on Wingate anaerobic power. Red Bull energy drink is commonly ingested in the hope that it will increase exercise performance. 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