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Cited by 12Sports Performance and TrainingMuscle metabolism and nutritionExercise and Physiological Responses

Dietary and Ergogenic Supplementation to Improve Elite Soccer Players’ Performance

Fernandes, Haniel·2021·Annals of Nutrition and Metabolism
DOI 10.1159/000516397
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Abstract

Background: Soccer is an extremely competitive sport, where the most match important moments can be defined in detail. Use of ergogenic supplements can be crucial to improve the performance of a high-performance athlete. Therefore, knowing which ergogenic supplements are important for soccer players can be an interesting strategy to maintain high level in this sport until final and decisive moments of the match. In addition, other supplements, such as dietary supplements, have been studied and increasingly referenced in the scientific literature. But, what if ergogenic supplements were combined with dietary supplements? This review brings some recommendations to improve performance of soccer athletes on the field through dietary and/or ergogenic supplements that can be used simultaneously. Summary: Soccer is a competitive sport, where the match important moments can be defined in detail. Thus, use of ergogenic supplements covered in this review can improve performance of elite soccer players maintaining high level in the match until final moments, such as creatine 3–5 g day−1, caffeine 3–6 mg kg−1 BW around 60 min before the match, sodium bicarbonate 0.1–0.4 g kg−1 BW starting from 30 to 180 min before the match, β-alanine 3.2 and 6.4 g day−1 provided in the sustained-release tablets divided into 4 times a day, and nitrate-rich beetroot juice 60 g in 200 mL of water (6 mmol of NO3− L) around 120 min before match or training, including a combination possible with taurine 50 mg kg−1 BW day−1, citrulline 1.2–3.4 g day−1, and arginine 1.2–6 g day−1. Key Messages: Soccer athletes can combine ergogenic and dietary supplements to improve their performance on the field. The ergogenic and dietary supplements used in a scientifically recommended dose did not demonstrate relevant side effects. The use of various evidence-based supplements can add up to further improvement in the performance of the elite soccer players.

AI snapshot

Written from the paper’s full text.

TL;DR

This narrative review compiles evidence-based dose recommendations for ergogenic and dietary supplements intended to improve elite soccer players' performance, and proposes several supplement combinations. It concludes that these supplements, used at scientifically recommended doses, showed no relevant side effects, but that it cannot confirm whether taking all of them together outperforms taking one or two.

Key findings

  • Recommended ergogenic doses: creatine 3–5 g day⁻¹ (or 0.075 g kg⁻¹ BW day⁻¹); caffeine 3–6 mg kg⁻¹ BW ~60 min before matches; sodium bicarbonate 0.1–0.4 g kg⁻¹ BW starting 30–180 min before matches; β-alanine 3.2–6.4 g day⁻¹ in sustained-release tablets divided 4 times a day over ~24 weeks; nitrate-rich beetroot juice 60 g beet in 200 mL water (6 mmol NO₃⁻/L) for at least 5 days, ~120 min before match/training with double consumption on match day.
  • Recommended dietary supplement doses: taurine 50 mg kg⁻¹ BW day⁻¹ for up to 8 weeks (preferably with caffeine 5 mg kg⁻¹ BW day⁻¹); citrulline 1.2–3.4 g day⁻¹ for at least 6 consecutive days (preferably with 1.2 g day⁻¹ arginine); arginine 1.2–6 g day⁻¹ for at least 14 consecutive days (preferably with 1.2 g day⁻¹ citrulline).
  • Cited individual study results include: 0.4 g kg⁻¹ BW NaHCO₃ giving 14% performance improvement and 7% lower perceived exertion in Yo-Yo tests; 0.4 g kg⁻¹ BW NaHCO₃ improving high-speed running (17–21 km h⁻¹) in 70% of 10 soccer players; beetroot juice improving Yo-Yo performance by +4% and +4.2% in separate studies; caffeine's additional ergogenic effect reaching >3% in two meta-analyses of >60 studies.
  • Combinations reported to improve performance: arginine with citrulline, caffeine with sodium bicarbonate, β-alanine with sodium bicarbonate, and taurine with caffeine.

Methods

  • Narrative review; literature searched in PubMed, Science Direct, and Google Scholar using keywords including 'creatine,' 'beta-alanine,' 'beet juice,' 'nitrate,' 'arginine,' 'taurine,' 'citrulline,' 'sodium bicarbonate,' 'performance,' 'soccer,' and 'elite soccer players,' with results included up to November 30, 2020.
  • Of 277 articles identified, 38 fulfilled the purpose of the review and are presented in Table 1; the compilation was evaluated by the author without preestablished inclusion or exclusion criteria.
  • No formal meta-analysis or quantitative synthesis was performed; findings are presented as narrative summaries of individual studies and dose recommendations.

Limitations

  • Stated by the paper: although results show a trend toward improvement, the author cannot confirm that taking all supplements mentioned would bring additional benefits over using 1 or 2 dietary and ergogenic supplements; randomized, crossover, controlled clinical studies using a compilation of supplements would be needed to assess whether taking all is better than taking 1 or 2 in synergy.
  • Evident from the text: the review was compiled by a single author without preestablished inclusion or exclusion criteria, and no systematic risk-of-bias or quality appraisal of the 38 included studies is described.
  • Evident from the text: several cited findings come from non-soccer or non-elite populations (e.g., runners, cyclists, swimmers, recreationally active men), and some studies report null results (e.g., acute arginine 0.15 g kg⁻¹ in RAST; 12 g citrulline improving cardiac output but not performance; 8 g citrulline showing no strength improvement).

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Integrity signals

Registry

Crossref · 10.1159/000516397This paper is marked retracted.

Cites

53 of 53 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

26 of 68 cited sources checked · 1 supported · 7 flagged · accuracy not yet measured

  • Premisecitation
    § Creatine · p. 4

    A controlled, crossover, randomized study with 12 soccer players found that 6 mg/kg BW caffeine 1 h before the test improved time to hit a penalty and countermovement jump performance.

    “A controlled, crossover, randomized study with 12 soccer players evaluated 6 mg kg -1 BW caffeine 1 h before the test and found improvements in time to hit a penalty and performance in the countermovement jump [17].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [17] source

      The Methods (Design and Supplementation; page unavailable) describe a randomized crossover test of sodium bicarbonate versus no supplement, not caffeine; participants were instructed to avoid caffeine before testing. The measured performance outcome was the Yo-Yo intermittent recovery test, not penalty-hit time or countermovement jumps. (LLM, conf=0.90)

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  • Premisecitation
    § Creatine · p. 5

    A double-blind, crossover, randomized study with 36 male players tested beet juice at 6 mmol NO3- for 5 days using Yo-Yo tests and showed significantly better improvement (+4%) in performance.

    “A double-blind, crossover, randomized study with 36 male players tested supplementation with beet juice at 6 mmol NO 3for a high-performance team sport for 5 days using Yo-Yo tests, and the results showed significantly better improvement (+4%) in the athletes' performance [46].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [46] source

      The Methods (pages unavailable) describe a randomized, double-blind crossover study, but it involved 21 amateur male runners given L-citrulline-enriched watermelon juice before half-marathons—not 36 team-sport players given beet juice for five days. The Discussion reports no significant difference in half-marathon times between the juice and placebo conditions, contrary to the claimed significant 4% performance improvement. (LLM, conf=0.91)

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  • Premisecitation
    § Creatine · p. 4

    A progressive dose regimen of NaHCO3 for 10 consecutive days (25 mg/kg BW on days 1-2, 50 mg/kg on days 3-5, 75 mg/kg on days 6-7, and 100 mg/kg on days 8-10) in 58 athletes resulted in significant improvement in peak power time on Wingate tests.

    “The progressive dose on the eve of the competition was used in a study with 58 athletes supplemented with NaHCO3 for 10 consecutive days with a progressive dose regimen (25 mg kg -1 BW on days 1 and 2, 50 mg kg -1 BW on days 3, 4, and 5, 75 mg kg -1 BW on days 6 and 7, and 100 mg kg -1 BW on days 8, 9, and 10); it resulted in a significant improvement in peak power time on Wingate tests [29].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [29] source

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  • Premisecitation
    § Creatine · p. 4

    A drink containing caffeine (3 mg/kg BW) and 7% carbohydrates (250 mL) tested on 18 soccer players induced significant improvements in vertical jump tests performed after a soccer match.

    “Two hundred fifty milliliters of a drink containing caffeine (3 mg kg -1 BW) and 7% carbohydrates was tested on 18 soccer players and was found to induce significant improvements in the vertical jump tests performed after a soccer match [18].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [18] source

      The Experimental Approach to the Problem describes sodium bicarbonate, a sodium-chloride placebo, or no supplement, followed by repeated cycling sprints. It does not describe a caffeine-and-carbohydrate drink or vertical jumps after a soccer match; the reported intervention and test are contrary to those attributed to this paper. Page numbers were not available in our copy. (LLM, conf=0.90)

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  • Premisecitation
    § Creatine · p. 5

    A randomized, crossover, double-blind, placebo-controlled study using 70 mL beet juice on 15 participants found significantly increased peak and average potency and blood lactate levels.

    “Another randomized, crossover, double-blind, placebo-controlled study using 70 mL of beet juice on 15 participants found significantly increased peak and average potency and blood lactate levels [47].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [47] source

      The Abstract Methods describe the same randomized, double-blind, placebo-controlled crossover design, but say that 22 trained men received L-citrulline, not that 15 participants received 70 mL of beet juice. The Methods list the measured blood markers as nitrite/nitrate and amino acids, not lactate. The paper therefore describes a different intervention and participant count from the study attributed to it. (LLM, conf=0.90)

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    Premisecitation
    § Creatine · p. 3

    Creatine supplementation acts on the fluid level of skeletal muscle cells, as demonstrated by a double-blind, controlled study with 0.3 g/kg BW creatine for 7 days in 13 soccer players, promoting ATP resynthesis and subsequent improvements in soccer players' performance.

    “In addition, creatine supplementation acts on the fluid level of skeletal muscle cells, as demonstrated by a double-blind, controlled work with 0.3 g kg -1 of body weight (BW) of creatine supplementation during 7 days involving 13 soccer players [9] promoting ATP resynthesis and subsequent improvements in the performance of soccer players.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [9] source

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    Premisecitation
    § Creatine · p. 4

    A study supplemented 16 men with 3 doses of sodium bicarbonate (0.1, 0.2, and 0.3 g/kg BW) and found increased blood NaHCO3 concentrations per dose (+2.0-5, +5.1-8.1, and +6.0-2.3 mmol/L) and dose over time (30-150, 40-165, and 75-180 min).

    “A study supplemented 16 men with 3 doses of sodium bicarbonate, 0.1 g kg -1 BW, 0.2 g kg -1 BW, and 0.3 g kg -1 BW, and found, respectively, increased blood NaHCO3 concentrations per dose (+2.0-5, +5.1-8.1, and +6.0-2.3 mmol L -1 ) and dose over time (30-150, 40-165, and 75-180 min) [25].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [25] source

      The Methods (Subjects; Study design) describe 17 male footballers assigned to β-alanine or placebo, not 16 men given three sodium bicarbonate doses. The Discussion explicitly says blood measures were not taken, so this study could not report the claimed blood bicarbonate concentrations or timing. (LLM, conf=0.91)

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    Premisecitation
    § Introduction · p. 3

    The Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine provided a guideline with the main sports supplements to improve athletes' performance.

    “Recently, the Academy of Nutrition and Dietetics, Dietitians of Canada (DC), and the American College of Sports Medicine (ACSM) provided a guideline prepared mainly by their members with the main sports supplements to improve the athletes' performance [3].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [3] source

      The Results section lists supplements reported during the 2002 and 2006 FIFA World Cups, while the Discussion addresses their use and the need for professional advice; page numbers are unavailable in our copy. A search for the three named organizations and a sports-supplement guideline found no passage saying they issued the guideline described in the claim. (LLM, conf=0.75)

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    Premisecitation
    § Creatine · p. 4

    Muscle carnosine is a dipeptide formed by β-alanine and L-histidine and participates in buffering of muscle cells by accepting protons during induced pH increase, with its limiting factor being β-alanine availability.

    “Muscle carnosine is a dipeptide formed by the combination of the amino acids β-alanine and L-histidine and participates in the buffering of muscle cells by accepting protons during the induced pH increase where your limiting factor is the availability of β-alanine [31].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [31] source

      The Discussion section on chronic beetroot-juice supplementation (page unavailable) says β-alanine increases muscle carnosine concentrations and that carnosine acts as an intracellular buffer. It does not state that carnosine is a β-alanine–L-histidine dipeptide, that it buffers by accepting protons, or that β-alanine availability limits its synthesis. The same passage says increased H+ production lowers pH, rather than raising it. (LLM, conf=0.87)

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    Premisecitation
    § Creatine · p. 4

    Sodium bicarbonate contains risks of gastrointestinal problems and metabolic alkalosis due to dose and time of ingestion, respectively.

    “However, it contains risks of gastrointestinal problems and metabolic alkalosis due to dose and time of ingestion, respectively [24].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [24] source

      The Methods report beta-alanine dosing and mild paresthesia, while the Discussion addresses beta-alanine and notes that blood pH was not measured. Sodium bicarbonate appears in reference titles, but no passage in our copy addresses gastrointestinal problems or metabolic alkalosis from its dose or ingestion timing (searched: sodium bicarbonate, gastrointestinal problems, metabolic alkalosis, dose and timing). (LLM, conf=0.76)

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    Premisecitation
    § Creatine · p. 4

    Caffeine supplementation is recognized by the International Olympic Committee and the International Sports Nutrition Society.

    “Caffeine supplementation is recognized by the International Olympic Committee and the International Sports Nutrition Society [12]”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [12] source

      The Introduction (page unavailable) discusses caffeine use in sport and says the World Anti-Doping Agency removed caffeine from its restricted-substances list in 2004. Searches for the International Olympic Committee and the International Sports Nutrition Society, including their Portuguese names, found no passage saying either organization recognizes caffeine supplementation. (LLM, conf=0.76)

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    Premisecitation
    § Creatine · p. 4

    Nitrate metabolism to nitric oxide requires oral cavity bacteria, and peak in blood occurs 2-3 h after ingestion.

    “However, nitrate metabolism to nitric oxide requires oral cavity bacteria [41] and peak in the blood occurs 2-3 h after ingestion [45]”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [41] source

      Citation [45] is attached to the claim that blood levels peak 2–3 hours after ingestion; the oral-bacteria claim is attributed to [41]. The Results report plasma taurine concentrations after eight weeks of supplementation, but our copy does not address a 2–3-hour blood peak after ingestion. Searches for that timing and for nitrate metabolism found no supporting passage. (LLM, conf=0.77)

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    • cites [45] source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § Introduction · p. 2

    Soccer is characterized by intermittent exercise of prolonged duration, with short and long duration and low and high intensity, involving sprints, changes of direction, jumps, accelerations, decelerations, walking or light running.

    “Soccer has characteristics of short and long duration and low and high intensity with intermittent exercises of prolonged duration [1] involving sprints, changes of direction, jumps, accelerations, and decelerations, besides walking or light running [2].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [1] source
    • cites [2] source

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    Premisecitation
    § Creatine · p. 3

    Creatine is synthesized from arginine, glycine, and methionine and stored about 95% in skeletal muscle, in free form or linked to phosphate as phosphocreatine.

    “synthesized from the amino acids arginine, glycine, and methionine and stored about 95% in the skeletal muscle and can be found in the free form or linked to a phosphate molecule (phosphocreatine) [7]”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [7] source

      The Background discusses creatine and phosphorylcreatine, and the Discussion refers to muscle phosphorylcreatine concentration. Neither section states that creatine is synthesized from arginine, glycine, and methionine, that about 95% is stored in skeletal muscle, or that it is present in free form. (LLM, conf=0.79)

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    Premisecitation
    § Creatine · p. 4

    Because muscle is unable to synthesize carnosine precursors, β-alanine supplementation induces an increase in intramuscular carnosine content, increasing buffering capacity.

    “As the muscle is unable to synthesize carnosine precursors, β-alanine supplementation induces an increase in intramuscular carnosine content increasing the buffering capacity [32].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [32] source

      The Introduction and Mechanisms sections discuss dietary nitrate and nitric-oxide-related effects on muscle contraction, not β-alanine supplementation. Searches for β-alanine, carnosine precursors, intramuscular carnosine, and buffering capacity found no passage addressing the attributed claim. (LLM, conf=0.78)

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    Premisecitation
    § Creatine · p. 4

    High bioavailability of nitric oxide increases release of calcium, improving contractile function of skeletal muscle and helping recovery of phosphocreatine reserves, preventing depletion during repeated efforts and improving release and reuptake of calcium in the sarcoplasmic reticulum.

    “The high bioavailability of nitric oxide increases release of calcium (Ca 2+ ) improving contractile function of the skeletal muscle [42] and helping recovery of phosphocreatine reserves, which prevents depletion during repeated efforts and improves release and reuptake of calcium in the sarcoplasmic reticulum [43, 44].”
    Quote in the paperSubstantial claim2 of 3 sources checked
    • cites [42] source

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    • cites [44] source

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    Premisecitation
    § Creatine · p. 4

    Dietary supplementation of nitrate through beet juice induces an increase in plasma nitrite concentration, subsequently increasing nitric oxide production.

    “Dietary supplementation of nitrate (NO3 -) through beet juice induces an increase in the concentration of nitrite (NO 2) in plasma [40] subsequently increasing the production of nitric oxide (NO) [41].”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [40] source

      The Discussion (p. 7) mentions beetroot juice only as a comparison for blood-pressure effects, and the References (p. 13) list a review of nitrate and beetroot juice supplementation. Searches for plasma nitrite and nitric oxide production found no passage addressing the claimed mechanism. (LLM, conf=0.76)

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    • cites [41] source

      The Results and Discussion report effects of taurine supplementation in swimmers, including increased plasma taurine and blood lactate; page numbers are unavailable in our copy. Searches for beet juice, dietary nitrate, plasma nitrite, and nitric oxide production found no passage addressing the cited claim. (LLM, conf=0.78)

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    Premisecitation
    § Creatine · p. 3

    Creatine is popular among soccer players.

    “Creatine is popular among soccer players [6]”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [6] source

      The Methods (Supplementation procedure; page unavailable) describe creatine given to soccer players as part of the trial, and the Discussion (page unavailable) describes its performance effects. Neither passage addresses how popular creatine is among soccer players; searches for popularity, common use, and prevalence found no such statement. (LLM, conf=0.72)

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    Premisecitation
    § Creatine · p. 4

    A study of 13 men tested 0.4 g/kg BW NaHCO3 in intermittent Yo-Yo running tests and obtained 14% improvement in performance and 7% decrease in perceived exertion rate.

    “A study of 13 men tested 0.4 g kg -1 BW of NaHCO3 in intermittent Yo-Yo running tests and obtained 14% improvement in performance and 7% decrease in the perceived exertion rate [26].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [26] source

  • May combine two claims.

    Premisecitation
    § Creatine · p. 4

    Sodium bicarbonate supplementation attenuates the decline in muscle pH, decreasing acidity and improving performance.

    “supplementation with sodium bicarbonate (NaHCO3) has been used, a buffering agent that attenuates the decline in muscle pH, decreasing acidity and improving performance [22, 23].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [22] source
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    Premisecitation
    § Creatine · p. 3

    In a randomized, double-blind, controlled study, 14 Brazilian elite soccer players who did not use creatine were supplemented with 20 g/day for 1 week divided into 4 equal doses to enhance phosphocreatine concentration, followed by 5 g/day for 6 weeks; significant improvements in jumping performance were obtained.

    “In another randomized, doubleblind, controlled study, parallel groups containing 14 Brazilian elite soccer players, who did not use creatine, were supplemented with 20 g day -1 for 1 week divided into 4 equal doses to enhance phosphocreatine concentration (overcompensation), followed by daily doses of 5 g during 6 weeks.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] source

  • May combine two claims.

    Premisecitation
    § Creatine · p. 5

    Taurine supplementation aids human maximal voluntary muscle contraction, reduces muscle damage, and brings additional benefits in hepatic metabolism.

    “Taurine supplementation aids human maximal voluntary muscle contraction [50], reduces muscle damage, and brings additional benefits in hepatic metabolism [51, 52].”
    Quote in the paperNot a substantial claim0 of 3 sources checked
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    • cites [52]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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    Premisecitation
    § Creatine · p. 5

    In 12 recreationally active men, taurine at 50 mg/kg BW/day for 7 days significantly improved time to exhaustion, peak power, and critical power on a cycle ergometer, and numerically increased biochemical lactate levels.

    “Twelve recreational active men participated in a crossover, randomized, controlled, double-blind study to test the effects of taurine on performance on a cycle ergometer with 50 mg kg -1 BW day -1 taurine dose for 7 days and concluded a significant improvement on time to exhaustion, peak power, and critical power, in addition to increasing the biochemical lactate levels numerically [60].”
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    • cites [60]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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    Interpretationcitation
    § Conclusion · p. 6

    Elite soccer players can improve on-field performance through dietary or ergogenic supplements such as taurine, citrulline, and arginine and ergogenic supplements such as creatine, caffeine, sodium bicarbonate, beet juice (nitrate), and beta-alanine.

    “Elite soccer players have nutritional weapons to improve performance on the field through dietary or ergogenic supplements such as taurine, citrulline, and arginine and ergogenic supplements such as creatine, caffeine, sodium bicarbonate, beet juice (nitrate), and beta-alanine.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Findings from non-soccer athlete populations, such as runners, cyclists, and recreationally active men, can be generalized to elite or professional soccer players.

  • May combine two claims.

    Premisecitation
    § Creatine · p. 5

    In 22 trained cyclists, citrulline at 2.4 g/day for 7 days significantly reduced total test time and significantly increased power.

    “A 3-week, double-blind, randomized, crossover, controlled study with 22 trained cyclists tested citrulline supplementation (2.4 g day -1 ) for 7 days using time tests and found significant reductions in total test time and significant increases at power [63].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [63]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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    Premisecitation
    § Creatine · p. 5

    A crossover, randomized, controlled study evaluated 3 g/day taurine for 8 weeks in 14 professional swimming athletes and concluded a possible increase in lactate production together with a possible additional effect on anaerobic lactic metabolism.

    “Another crossover, randomized, controlled model study evaluated 3 g day -1 of taurine for 8 weeks in 14 professional swimming athletes and concluded a possible increase in lactate production together with a possible additional effect on anaerobic lactic metabolism [55].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [55]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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    Premisecitation
    § Creatine · p. 5

    In 28 soccer players, 6 g/day arginine for 14 days influenced lactate levels and reduced post-workout muscle damage by decreasing lactate dehydrogenase.

    “Twenty-eight soccer players were selected and supplemented with 6 g arginine during 14 days, and their performance in the RAST protocol on six 35-m consecutive sprints with 10 s of active rest was tested. It was concluded that”
    • Also stated in: § Creatine · p. 5 · plain
      “Fernandes dose influenced the body's lactate levels and reduced the damage after workout in the muscle by decreasing lactate dehydrogenase [70].”
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    • cites [70]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation
    § Creatine · p. 5

    A randomized, crossover, controlled study evaluated 5 g/day taurine for 1 week in 20 athletes and concluded improvements in reaction time plays.

    “Another study, with a randomized, crossover, and controlled model, evaluated the supplementation of 5 g day -1 of taurine for 1 week in 20 athletes and concluded improvements in reaction time plays [54].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [54]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation
    § Creatine · p. 5

    Citrulline is converted into arginine in the kidneys, and at the endothelial vessel wall endothelial nitric oxide synthase converts arginine to nitric oxide and citrulline, increasing muscle relaxation.

    “Citrulline supplementation is involved in arginine metabolism; in the kidneys, citrulline is converted into arginine up to the endothelial vessel wall where endothelial nitric oxide synthase converts arginine to nitric oxide and citrulline to start the cascade of using Ca 2+ from the sarcoplasma to the sarcoplasmic reticulum, increasing muscle relaxation [61].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [61]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation
    § Creatine · p. 5

    In 10 healthy trained men, acute 12 g citrulline significantly improved cardiac output frequency but did not improve performance.

    “Ten healthy, trained men participated in a crossover, randomized, doubleblind, placebo-controlled study to test the acute effects of 12 g citrulline in high-performance tests on 3 occasions separated by 7 days (washout) concluding significant improvement in frequency cardiac output but not in performance [65].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [65]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationcitation
    § Conclusion · p. 6

    Combinations of arginine with citrulline, caffeine with sodium bicarbonate, beta-alanine with sodium bicarbonate, and taurine with caffeine have been demonstrated to improve performance.

    “Besides everything, some combinations have been demonstrated to improve performance such as arginine with citrulline, caffeine with sodium bicarbonate, beta-alanine with sodium bicarbonate, and taurine with caffeine.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation
    § Creatine · p. 5

    Other studies with young strength athletes found that taurine can mitigate muscle pain and induce positive effects on muscle contraction.

    “Besides these, other studies with young strength athletes found that taurine can mitigate muscle pain and induce positive effects on muscle contraction [56, 57].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [56]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [57]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

27 of 27

  • The paper relies on this without support.

    Findings from studies in non-soccer or mixed athlete populations can be generalized to elite soccer players.

    “Taurine | 50 mg kg -1 BW day -1 for up to 8 weeks and preferably combined with caffeine at 5 mg kg -1 BW day -1”

  • The paper relies on this without support.

    The ergogenic and dietary supplements used at scientifically recommended doses do not have relevant side effects.

    “The ergogenic and dietary supplements used in a scientifically recommended dose did not demonstrate relevant side effects.”

  • The paper relies on this without support.

    Combining the recommended ergogenic and dietary supplements does not produce adverse interactions that outweigh benefits.

    “Soccer athletes can combine ergogenic and dietary supplements to improve their performance on the field.”

  • The paper relies on this without support.

    Taurine's use for improving soccer performance has not been much studied in the scientific literature.

    “Actually, its use for improving soccer performance was not much studied in the scientific literature.”

  • The paper relies on this without support.

    The non-systematic literature search without preestablished inclusion or exclusion criteria identified the relevant evidence.

    “The compilation of studies was evaluated by the author without obeying preestablished inclusion or exclusion criteria, and they only belonged to the work context.”

  • The paper relies on this without support.

    Findings from non-soccer athlete populations, such as runners, cyclists, and recreationally active men, can be generalized to elite or professional soccer players.

    “In summary, the taurine supplementation recommended for professional soccer players consists of 50 mg kg -1 BW day -1 for up to 8 weeks and preferably combined with caffeine at 5 mg kg -1 BW day -1 .”
6 of 6

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Related

Authors
Fernandes, H.
Corresponding author
Fernandes, Haniel
ORCID
Fernandes, Haniel
Venue
Annals of Nutrition and Metabolism
Publisher
S. Karger AG
Published
2021
Volume
77
Issue
4
Pages
197-203
ISSN
  • 0250-6807 (ISSN-L)
  • 1421-9697
DOI
10.1159/000516397
OpenAlex
W3171032203
Semantic Scholar
60adf3387e1c8e964686eeb41aed2c9e194c541b
Cited by
12
References
53
Citations by year
2026: 1 · 2025: 1 · 2024: 2 · 2023: 3 · 2022: 4 · 2021: 1
FWCI
2.22
Type
journal article
Language
en
Status
Retracted
Update notices
Open access
closed
Licence
Locations
  • Annals of Nutrition and Metabolism (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Muscle metabolism and nutrition
  • Health Sciences › Medicine › Rehabilitation › Exercise and Physiological Responses
Keywords
soccer, ergogenic aids, dietary supplements, elite athletes, creatine, caffeine, sodium bicarbonate, beta-alanine, beetroot juice, nitrate, taurine, citrulline, L-arginine, athletic performance
MeSH terms
Creatine, Humans, Soccer, Dietary Supplements, Athletic Performance, Athletes, Performance-Enhancing Substances

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