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Effects of dietary supplements on athletic performance in elite soccer players: a systematic review.
Abreu, R, Oliveira, CB, Costa, JA, Brito, J, Teixeira, VH
Journal of the International Society of Sports Nutrition. 2023;20(1):2236060
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Dietary supplements are used by elite soccer players to improve performance and recovery. However, it is unclear as to whether the research can back up the reasons for their use. This systematic review of 18 randomised control trials aimed to determine any effects of dietary supplements on elite, adult soccer players. The results showed that studies on the use of supplementation in soccer players has been completed using caffeine, caffeinated energy drinks, creatine, protein, beverages with carbohydrates and electrolytes, tart cherry juice, nitrate-rich beetroot juice, yohimbine, Resurgex Plus, and sodium and potassium bicarbonate with potassium, magnesium, and calcium citrate. It was concluded that the use of creatine, protein, and caffeine may be of benefit to the performance of elite soccer players. The use of yohimbine was strongly discouraged due to unclear safety data. There was a lack of evidence for the use of any of the other supplements and it was concluded that more studies need to be completed. This study could be used by healthcare professionals to understand that certain supplements may enhance athletic performance in elite soccer players, but more research is encouraged.
Abstract
Dietary supplements are widely used among athletes, and soccer players are no exception. Nevertheless, evidence supporting the use of dietary supplements aiming to enhance performance in soccer is somewhat contradictory, scarce, or even nonexistent. Thus, the present study aimed to systematically review and synthesize the effects of dietary supplements on athletic performance (e.g. distance covered, sprinting, jump performance) in elite soccer players. Studies enrolling highly trained, elite, and world-class soccer players using dietary supplements were searched in MEDLINE/PubMed, Web of Science, Scopus, and EBSCO databases in June 2022. In total, 1043 studies were identified, and 18 met the eligibility criteria. The studies evaluated the impacts on athletic performance of several dietary supplements, including caffeine, creatine, protein, beverages with carbohydrates and electrolytes, tart cherry juice, nitrate-rich beetroot juice, sodium bicarbonate with minerals, yohimbine, and a proprietary nutraceutical blend. Caffeine supplementation in doses between 3 and 6 mg/kg of body mass may improve jump height and sprint ability, particularly in female players, but individual response to caffeine must be considered. Creatine may improve sprint, agility, and in female players, jump performance. Protein supplementation can improve sprint and jump performance between matches, especially if protein ingested from food is not up to recommendations. Beverages containing carbohydrates and electrolytes can be used as part of the strategies to achieve carbohydrate intake during training and match-days but used alone do not benefit athletic performance. Tart cherry juice might be useful for maintaining athletic performance after matches that produce higher force loss and exercise-induced muscle damage, although polyphenols from the diet might attenuate the effects of tart cherry supplementation. Nitrate-rich beetroot concentrate can attenuate performance decrease in the days following matches. Further investigation with sodium bicarbonate alone is necessary, as supplementation protocols with elite players included other substances. Finally, the available data does not support yohimbine supplementation or the use of Resurgex Plus® to improve athletic performance in elite soccer players. Still, more well-designed research with elite soccer players is needed to improve support and advice regarding the use of dietary supplements for athletic performance enhancement.
2.
Caffeinated Drinks and Physical Performance in Sport: A Systematic Review.
Jiménez, SL, Díaz-Lara, J, Pareja-Galeano, H, Del Coso, J
Nutrients. 2021;13(9)
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Caffeine is a well-documented ergogenic aid and is often consumed by athletes to enhance overall performance. While this is established, there is currently no clarification on whether the performance-enhancing effects of caffeine differ depending on the category of sport. The aim of this study is to assess the effects of caffeinated drinks in various categories including endurance, power-based, team, and skill-based sports. This review included 37 studies and found caffeinated drinks to be an effective tool for increasing several aspects of individual performance. These drinks were more beneficial during long-duration exercise when they served as both rehydration and caffeine supplementation, but played an ergogenic role in each of the sports categories included in this study. Based on the current literature, the authors conclude caffeinated drinks to be an effective supplementation for athletes. They also suggest practising caution when using these drinks to increase ahtletic performance as the potential side effects were not a focus of this particular review.
Abstract
Caffeine (1,3,7-trimethylxanthine) is one of the most common substances used by athletes to enhance their performance during competition. Evidence suggests that the performance-enhancing properties of caffeine can be obtained by employing several forms of administration, namely, capsules/tablets, caffeinated drinks (energy drinks and sports drinks), beverages (coffee), and chewing gum. However, caffeinated drinks have become the main form of caffeine administration in sport due to the wide presence of these products in the market. The objective of this systematic review is to evaluate the different effects of caffeinated drinks on physical performance in various sports categories such as endurance, power-based sports, team sports, and skill-based sports. A systematic review of published studies was performed on scientific databases for studies published from 2000 to 2020. All studies included had blinded and cross-over experimental designs, in which the ingestion of a caffeinated drink was compared to a placebo/control trial. The total number of studies included in this review was 37. The analysis of the included studies revealed that both sports drinks with caffeine and energy drinks were effective in increasing several aspects of sports performance when the amount of drink provides at least 3 mg of caffeine per kg of body mass. Due to their composition, caffeinated sports drinks seem to be more beneficial to consume during long-duration exercise, when the drinks are used for both rehydration and caffeine supplementation. Energy drinks may be more appropriate for providing caffeine before exercise. Lastly, the magnitude of the ergogenic benefits obtained with caffeinated drinks seems similar in women and men athletes. Overall, the current systematic review provides evidence of the efficacy of caffeinated drinks as a valid form for caffeine supplementation in sport.
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Caffeine Supplementation and Physical Performance, Muscle Damage and Perception of Fatigue in Soccer Players: A Systematic Review.
Mielgo-Ayuso, J, Calleja-Gonzalez, J, Del Coso, J, Urdampilleta, A, León-Guereño, P, Fernández-Lázaro, D
Nutrients. 2019;11(2)
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Ergogenic aids, supplements that improve athletic performance, have become increasingly important in the global soccer community. Caffeine has been shown to produce ergogenic effects in both endurance sports and sprint performance. Recent studies have investigated the impact of caffeine intake on soccer physical performance however no review has evaluated these studies. The purpose of this systematic review was to critically evaluate the effect of acute caffeine ingestion on soccer players’ physical performance, muscle damage and perceived fatigue. This review included 17 articles, 12 of which examine soccer-specific abilities and 5 of which examine muscle damage. Based on the existing literature, caffeine was found to have ergogenic effects on jump height, sprint ability, passing accuracy and running distances during a soccer game. Caffeine was found to produce no effect on exercise-induced muscle damage however more research is needed in this area. Based on these results, the authors conclude a moderate dose of caffeine (3-6 mg/kg) may enhance physical performance specific to soccer players.
Abstract
Soccer is a complex team sport and success in this discipline depends on different factors such as physical fitness, player technique and team tactics, among others. In the last few years, several studies have described the impact of caffeine intake on soccer physical performance, but the results of these investigations have not been properly reviewed and summarized. The main objective of this review was to evaluate critically the effectiveness of a moderate dose of caffeine on soccer physical performance. A structured search was carried out following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines in the Medline/PubMed and Web of Science databases from January 2007 to November 2018. The search included studies with a cross-over and randomized experimental design in which the intake of caffeine (either from caffeinated drinks or pills) was compared to an identical placebo situation. There were no filters applied to the soccer players' level, gender or age. This review included 17 articles that investigated the effects of caffeine on soccer-specific abilities (n = 12) or on muscle damage (n = 5). The review concluded that 5 investigations (100% of the number of investigations on this topic) had found ergogenic effects of caffeine on jump performance, 4 (100%) on repeated sprint ability and 2 (100%) on running distance during a simulated soccer game. However, only 1 investigation (25%) found as an effect of caffeine to increase serum markers of muscle damage, while no investigation reported an effect of caffeine to reduce perceived fatigue after soccer practice. In conclusion, a single and moderate dose of caffeine, ingested 5⁻60 min before a soccer practice, might produce valuable improvements in certain abilities related to enhanced soccer physical performance. However, caffeine does not seem to cause increased markers of muscle damage or changes in perceived exertion during soccer practice.
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Effect of protein and carbohydrate solutions on running performance and cognitive function in female recreational runners.
Gui, Z, Sun, F, Si, G, Chen, Y
PloS one. 2017;12(10):e0185982
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Research has shown that consuming a carbohydrate-electrolyte solution (CES) during endurance exercise can improve performance, delay fatigue and ameliorate post-exercise cognitive dysfuction when compared with a noncaloric placebo (PLA). The addition of protein to the CES (CPES) has been suggested to increase these benefits however the current data is limited. The aim of this crossover study was to investigate whether the added protein to a CES would improve exercise performance and cognitive function in 11 female recreational marathon runners. Participants were randomised to consume one of the three solutions (CES, CPES or PLA) every 2.5km during a 21km run, with a 28-day interval, and their VO2max and cognitive function were recorded after the run. This study showed that CES improved endurance performance compared with PLA, however adding protein to the CES did not provide any additional performance benefit. The CPES solution did benefit visual motor speed compared to PLA, but no differences were found in the other cognitive function tests.
Abstract
This study compared the effects of a carbohydrate-electrolyte-protein solution (CEPS, 2% protein plus 4% carbohydrate), carbohydrate-electrolyte solution (CES, 6% carbohydrate), and noncaloric sweetened placebo (PLA) on both 21-km running performance and cognitive function. Eleven female recreational endurance runners performed a 21-km time-trial running on three occasions, separated by at least 28 days. In a randomized cross-over design, they ingested CEPS, CES, or PLA at a rate of 150 mL every 2.5 km with no time feedback. A cognitive function test was performed before and after the run. Participants ingested approximately 24 g/h carbohydrate plus 12 g/h protein in CEPS trial, and 36 g/h carbohydrate in CES trial during each 21-km trial. Time to complete the time-trial was slightly shorter (P < 0.05) during CES (129.6 ± 8.8 min) than PLA (134.6 ± 11.5 min), with no differences between CEPS and the other two trials. The CEPS trial showed higher composite of visual motor speed than the PLA trial (P < 0.05). In conclusion, CES feedings might improve 21-km time-trial performance in female recreational runners compared with a PLA. However, adding protein to the CES provided no additional time-trial performance benefit. CEPS feeding during prolonged exercise could benefit visual motor speed compared to PLA alone, but no differences in the performance of the other cognitive function tests were found.