PRIME(X) - PreWorkout

• This study examined twenty-two trained males who consumed 2.4 g/day of L-Citrulline for 7 days, and on day 8 they consumed 2.4 g of L-Citrulline 1 hour before a 4-km cycling race.
• Compared to the placebo group, the group supplementing with L-Citrulline had significantly increased plasma L-Arginine levels leading to more nitric oxide production.
• The L-Citrulline group had completed the race in significantly faster times than the placebo group, while also being able to exert a higher power output.
• Subjective reports of muscle fatigue after the race were also lower for the L-Citrulline group.

Suzuki T, Morita M, Kobayashi Y, Kamimura A. J Int Soc Sports Nutr. 2016 Feb 19;13:6. doi: 10.1186/s12970-016-0117-z.

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• This study examined 17 voluntary male pre-professional cyclists randomly assigned to either placebo or L-citrulline-malate groups.
• The subjects participated in a 137-km cycling race, and blood samples were taken at basal level, 15 minutes after the race, and after 3 hours of recovery.
• The group that received 6 grams of L-citrulline-malate before the race had significantly increased plasma levels of citrulline, arginine, ornithine, urea, creatinine, and nitrite, indicating enhanced use of branched chain amino acids during exercise, and enhanced production of nitric oxide (NO).
• The L-citrulline-malate group also had a higher increase in growth hormone after the race.

Sureda A, Córdova A, Ferrer MD, Pérez G, Tur JA, Pons A. Eur J Appl Physiol. 2010 Sep;110(2):341-51. doi: 10.1007/s00421-010-1509-4.

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• The purpose of this experiment was to examine the effects of Nitrosigine (Arginine) and Citrulline-Malate on vasodilation using ultrasound and flow mediated dilation (FMD).
• In this randomized, double blind study, 24 healthy and active adults (16 males and 8 females) reposrted for three seperate trials to measure vasodilation, each preceded by a 7-day washout period.
• Baseline FMD was measured following supplementation of either 8g Citrulline-Malate, 1.5g Nitrosigine (arginine), or 8g placebo (dextrose).
• Citrulline-malate supplementation resulted in the largest average increase in FMD (25%) compared to 23% for the Nitrosigine group, and -2% for the placebo group.
• This increase in vasodilation is indicative of increased skeletal muscle blood flow which results in potential improvements in exercise performance and recovery.

Rogers JM, Gills J, Gray M. J Int Soc Sports Nutr. 2020 Feb 24;17(1):12. doi: 10.1186/s12970-020-00343-y.

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• This study examined the effects of a single dose of Citrulline-Malate on the performance of flat barbell bench press for 41 male subjects.
• The participants ingested 8 grams of Citrulline-Malate or a placebo 1 hour before the workout. The subjects' resistance was tested using a reps-to-failure test at 80% of their 1 repetition maximum weight for 8 total sets of bench press. (4 sets at the beginning of a chest workout, and 4 sets at the end.
• The Citrulline-malate group increased number of reps performed across 8 total sets, and achieved 52% more repetitions than the placebo group in the last set of the workout.
• The Citrulline-malate group also reported decreased feeling of muscle soreness up to 48 hours post workout.

Pérez-Guisado J, Jakeman PM. J Strength Cond Res. 2010 May;24(5):1215-22. doi: 10.1519/JSC.0b013e3181cb28e0.

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• This goal of this study was to examine how a seven-week supplementation regimen of creatine paired with resistance training affected body composition, muscle mass, muscle strength and power, and serum and muscle creatine levels in 30 non-resistance-trained males
• In this double-blind experiment, participants were randomly assigned to either Creatine Monohydrate (CRT), Creatine Ethyl Ester (CEE), or maltodextrose placebo (PLA) groups. The participants underwent a loading phase of 20 grams/day for 5 days followed by 5 grams/day for 42 days.
• Throughout the study, total serum and muscle creatine levels were higher in the CRT group compared to placebo and CEE, confirming previous research showing that Creatine monohydrate is the superious form of creatine supplementation.

Spillane M, Schoch R, Cooke M, Harvey T, Greenwood M, Kreider R, Willoughby DS. J Int Soc Sports Nutr. 2009 Feb 19;6:6. doi: 10.1186/1550-2783-6-6.

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• The purpose of this study was to examine the effects of Creatine Monohydrate and polyethylene glycosylated (PEG) creatine on muscular strength, endurance, and power output.
• The study examined 58 healthy men who were randomly assigned to 1 of 4 groups; placebo (PL = 3.6 grams of cellulose), CM (5 grams of creatime monohydrate), small dose PEG creatine (1.25 grams), or moderate dose PEG creatine (2.4 grams).(
• Test results were compared before and after a 30-day supplementation period.
• Creatime Monohydrate supplementation resulted in the biggest improvements across the board, including vertical jump height, peak and mean power output, 1 repetition maximums on bench press and leg press, and repetitions to failure on bench press and leg press.

• This study examined the efects of Beta-Alanine supplementation on physical work capacity, ventilatory threshold, maximal oxygen consumption, and time to exhaustion on an incremental cycle ergometry test.
• 22 women were randomly assigned to groups of Beta-Alanine (6.4 grams/day divided into 4 doses) or placebo supplementation for 28 days and tested before and after supplementation.
• The women supplementing with Beta-Alanine had significantly improved their physical capacity, ventilatory thershold, and time to exhaustion compared to the placebo group.

Stout JR, Cramer JT, Zoeller RF, Torok D, Costa P, Hoffman JR, Harris RC, O'Kroy J. Amino Acids. 2007;32(3):381-6. doi: 10.1007/s00726-006-0474-z.

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• This study examined the effectiveness of Beta-Alanine as an ergogenic aid in tests of anaerobic power output after 8 weeks of training in 37 collegiate wrestlers (WR) and football (FB) players.
• In a double-blind manner, the subjects ingested either Beta-Alanine (4 grams/day) or placebo, and were tested before and after 8 weeks of treatment in a timed 300-yard shuttle, a 90° flexed-arm hang, and body composition.
• While the results were not statistically significant, the beta-alanine groups for both wrestlers and football players had improved their performance on all the tests, with performance improvements being greatest for the football players.

Kern BD, Robinson TL. J Strength Cond Res. 2011 Jul;25(7):1804-15. doi: 10.1519/JSC.0b013e3181e741cf.

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• In this meta-analysis, a comprehansive search of literature was emplyed to gather as much reliable information about the ergogenic effects of Beta-Alanine as a performance supplement.
• Fifteen published manuscripts were includde in this analysis, reporting on the results of 57 different measures across 23 exercise tests usine 18 supplementation regimes on a total of 360 participants.
• The results indicate thet Beta-Alanine supplementation is most effective at improving performance in the 60-240 second range of exercise, while also improving performance at longer times compared to a placebo.

Hobson RM, Saunders B, Ball G, Harris RC, Sale C. Amino Acids. 2012 Jul;43(1):25-37. doi: 10.1007/s00726-011-1200-z.

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• This study aimed to investigate if athlete performance is related to muscle carnosine content, and if Beta-Alanine supplementation improves performance in elite rowers.
• 18 elite Belgian rowers supplemented for 7 weeks with Beta-Alanine (5 grams/day) or placebo and were evaluated before and after treatment.
• Fundamentally, there was a positive correlation of muscle carnosine concentration with the rowers' speeds at 100m, 500m, 2000m, and 6000m.
• The rowers who supplemented with Beta-Alanine had 45% higher carnosine concentration in the soleus muscle, and 28% higher concentrations in the gastronemius muscle.
• The Beta-Alanine group was 4.3 seconds faster than the placebo group in a 2000m race, while they were actually 0.3 seconds slower before supplementation.

Baguet A, Bourgois J, Vanhee L, Achten E, Derave W. J Appl Physiol (1985). 2010 Oct;109(4):1096-101. doi: 10.1152/japplphysiol.00141.2010.

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• This study examined the dose-response relationship between the volume of beetroot juice ingested and its physiological effects.
• 10 male subjects ingested 70, 140, or 280 mL of beetroot juice (containing 4.2-16.8 mmol of NO3), or NO3-depleted juice as a placebo.
• The subjects' resting plasma NO2 and NO3 levels were evaluated over 24 hours, and the results show a direct dose-dependent increase in plasma NO3 and NO2 concentrations following beetroot juice supplementation for 24 hours, indicating an increase in Nitric Oxide levels compared to the placebo groups.
• The subjects were also subjected to intense cycling exercise tests on seperate occasiond after suplmentation of beetroot juice or placebo, and showed the same dose-dependent response to beetroot juice.
• The results also showed a 12-14% increse in time to exhaustion for the beetroot group, while actually decreasing their steady-state oxygen uptake. This indicates an incresed efficiency of oxygen utilization after beetroot supplementation.

Wylie LJ, Kelly J, Bailey SJ, Blackwell JR, Skiba PF, Winyard PG, Jeukendrup AE, Vanhatalo A, Jones AM. J Appl Physiol (1985). 2013 Aug 1;115(3):325-36. doi: 10.1152/japplphysiol.00372.2013.

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• This study investigated the effects of acute dietary nitrate supplementation on power output, VO2, and performance during 4 km and 16.1 km cycling time trials.
• 9 elite male cyclists were assigned randomly to consume either 500 mL of beetroot juice or a nitrate-depleted placebo juice before completing either 4 km or 16.1 km time trials.
• The group consuming beetroot juice significantly increased the mean power output during both 4 km and 16.1 km races. Beetroot juice supplementation also resulted in a 2.8% performance increase in the 4 km race, and a 2.7% performance increase in the 16.1 km race.

Lansley KE, Winyard PG, Bailey SJ, Vanhatalo A, Wilkerson DP, Blackwell JR, Gilchrist M, Benjamin N, Jones AM. Med Sci Sports Exerc. 2011 Jun;43(6):1125-31. doi: 10.1249/MSS.0b013e31821597b4.

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• The goal of this study was to evalate the dose-dependent effects of caffeine supplementation on sprint cycling performance.
• 17 trained male subjects were used in this randomized, double-blind, placebo-controlled study.
• The subjects completed 7 maximal effort 10-second sprints on a cycle ergometer after being given a capsule containing either caffeine or a gelatin placebo. The caffeine doses given ranged from 2, 4, 6, 8, and 10 mg/kg bodyweight (140mg-680mg for a 150 lbs person).
• There was no significant improvement in power output at any dose of caffeine compared to the placebo group, although there was a trend of faster time to peak power with caffeine supplementation.

Glaister M, Patterson SD, Foley P, Pedlar CR, Pattison JR, McInnes G. J Strength Cond Res. 2012 Apr;26(4):1001-5. doi: 10.1519/JSC.0b013e31822ba300.

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• The purpose of this study was to investigate whether caffeine is able to counteract the morning reduction in neuromuscular performance associated with the circadian rhythm pattern.
• 12 resistence-trained men were subjected to a battery of neuromuscular tests under three different conditions; 10:00 AM with caffeine ingestion @ 3 mg/kg (~210 mg for a 150 lbs person), 10:00 AM with placebo ingestion, and 6:00 PM with placebo ingestion.
• The subjects were tested on their bar displacement velocity during squats and bench press for power and strength, and isometric voluntary and electrically evoked contraction of their quadriceps.
• The results show that Caffeine supplementation increased the AM group's performance to levels consistent with the PM placebo group.
• Caffeine supplementation also resulted in higher increases in epinephrine and norepinephrine post-exercise.
• These results conclude that caffeine supplementation may give a significant neuromuscular performance advantage during early morning workouts.

Mora-Rodríguez R, García Pallarés J, López-Samanes Á, Ortega JF, Fernández-Elías VE. PLoS One. 2012;7(4):e33807. doi: 10.1371/journal.pone.0033807.

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• This study aimed to determine the effects of two different doses of caffeine on muscle performance in 12 active participants.
• The subjects ingested caffeine at either 1 or 3 mg/kg of bodyweight (70mg or 210mg for a 150 lbs person) or a caffeine-free placebo before being tested on half-squat and bench-press power production with loads ranging from 10% to 100% of their 1 repetition maximum.
• Power output was increased by the higher dose of caffeine compared to placebo, but not by the lower dose.

• Del Coso J, Salinero JJ, González-Millán C, Abián-Vicén J, Pérez-González B. J Int Soc Sports Nutr. 2012 May 8;9(1):21. doi: 10.1186/1550-2783-9-21.

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• The aim of this study was to examine the effects of caffeine supplementation on sprint running performance in 21 physically active men.
• The subjects ingested a capsule containing either caffeine at 5mg/kg bodyweight (350mg for 150 lbs person) or a maltodextrin placebo before completing a multiple sprint running trial (12 x 30 meters, repeated at 35 second intevals).
• Caffeine supplementation resulted in 1.4% resuction in sprint times at best, and also resulted in 3.4-bpm incresae in mean heart rate.

• Glaister M, Howatson G, Abraham CS, Lockey RA, Goodwin JE, Foley P, McInnes G. Med Sci Sports Exerc. 2008 Oct;40(10):1835-40. doi: 10.1249/MSS.0b013e31817a8ad2.

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• This study examined caffeine's effects on affective states during prolonged exercise.
• 12 endurance-trained male cylists performed 90 minutes of exercise at 70% VO2max after ingesting 6 mg/kg of caffeine (425mg for 150 lbs person) or placebo.
• Results showed that both pleasure ratings and ratings of perceived exertion were more favorable in the caffeine group overall, though the magnitude of these effects was minimal to moderate at best.

Backhouse SH, Biddle SJ, Bishop NC, Williams C. Appetite. 2011 Aug;57(1):247-52. doi: 10.1016/j.appet.2011.05.304.

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• This study investigated the anxiogenic effects of caffeine consumption on people with genetic predisposition to anxiety, as well as the effect's dependence on habitual levels of caffeine consumption.
• The subjects consisted of 162 non/low (NL) caffeine comsumers and 217 medium/high (MH) caffeine consumers. The subjects rated their anxiety, alertness, and headaches before and after 100mg caffeine and again after 150mg caffeine 90 minutes later, of after two placebo doses.
• The results confirmed the genetic connection between participants with single-nucleotide polymorphisms in the adenosine receptors, and also showed increased anxiety from caffeine in low habitual caffeine consumers independent of their genotype.

Rogers PJ, Hohoff C, Heatherley SV, Mullings EL, Maxfield PJ, Evershed RP, Deckert J, Nutt DJ. Neuropsychopharmacology. 2010 Aug;35(9):1973-83. doi: 10.1038/npp.2010.71.

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• This study examined the effects of L-theainne on attention and reactiontime response in 18 normal and healthy college students divided into two groups referred to as high anxiety propensity and minimal anxiety propensity.
• Both groups received L-theanine (200mg/100mL water) and placebo (100mL water) in a double blind repeated testing of visual attention tasks as well as sudio response tests. Assesments performed 15 to 60 minutes after treatment.
• The results show that L-theanine had a greater effect in increasing the correct response ration for people with high anxiety, and less so in people with minimal anxiety. L-theanine also improved reaction time to response.

• Akiko Higashiyama, Hla Hla Htay, Makoto Ozeki, Lekh R. Juneja, Mahendra P. Kapoor. Journal of Functional Foods. Volume 3, Issue 3. 2011 Pages 171-178, ISSN 1756-4646. doi:10.1016/j.jff.2011.03.009.

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• This study investigated the acute cognitive and mood effects of L-theanine (250mg) and caffeine (150mg), in isolation and in combination on 24 healthy subjects.
• Testing was done on two seperate occasions 7 days apart to examine cognitive effects and mood.
• The results show the best performance improvements from the combine L-theanine and caffeine consumption in reaction time, accuracy measures, and word recognition. Combination of L-theanine with caffeine also results in reduced feelings of tiredness and headach, with increased alertness.

Haskell CF, Kennedy DO, Milne AL, Wesnes KA, Scholey AB. Biol Psychol. 2008 Feb;77(2):113-22. doi: 10.1016/j.biopsycho.2007.09.008.

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• This study investigated the efects of both L-theanine and caffeine, seperately or together, on behavioral and electrophysiological indices of tonic (background) and phasic (event-related) visuospatial attentional deployment.
• Subjects underwent 4 days of testing, ingesting either placebo, 100mg L-theanine, 50mg caffeine, or both L-theanine and caffeine combined. The testing consisted of cued shifts of attention to the left or right visual in anticipation of an imperative stimulus requiring discrimination.
• The results shows the highest hit rates and discriminatory indexes in the combine L-theanine and caffeine group.
• Electrophysiological readings showed lower overall tonic alpha brain waves in the L-theanine + caffeine group, indicating deployment of attentional resources to the visual modality which may underlie the improved performance measures.

Kelly SP, Gomez-Ramirez M, Montesi JL, Foxe JJ. J Nutr. 2008 Aug;138(8):1572S-1577S. doi: 10.1093/jn/138.8.1572S.

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