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Effects of Creatine Monohydrate on Endurance Performance in a Trained Population: A Systematic Review and Meta-analysis

Authors:
Julen Fernández-Landa at University of Deusto
Julen Fernández-Landa
Asier Santibañez at University of the Basque Country
Asier Santibañez
Nikola Todorović at University of Novi Sad
Nikola Todorović
Valdemar Štajer at University of Novi Sad
Valdemar Štajer
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Background There is robust evidence that creatine monohydrate supplementation can enhance short-term high-intensity exercise in athletes. However, the effect of creatine monohydrate supplementation on aerobic performance and its role during aerobic activities is still controversial. Objective The purpose of this systematic review and meta-analysis was to evaluate the supplementation effects of creatine monohydrate on endurance performance in a trained population. Methods The search strategy in this systematic review and meta-analysis was designed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and PubMed/MEDLINE, Web of Science, and Scopus databases were explored from inception until 19 May, 2022. Only human experimental trials, controlled with a placebo group, evaluating the effects of creatine monohydrate supplementation on endurance performance in a trained population were analyzed in this systematic review and meta-analysis. The methodological quality of included studies was evaluated using the Physiotherapy Evidence Database (PEDro) scale. Results A total of 13 studies satisfied all the eligibility criteria and were included in this systematic review and meta-analysis. The results for the pooled meta-analysis showed a non-significant change in endurance performance after creatine monohydrate supplementation in a trained population (p = 0.47), with a trivial negative effect (pooled standardized mean difference = − 0.07 [95% confidence interval − 0.32 to 0.18]; I² = 34.75%). Further, after excluding the studies not evenly distributed around the base of the funnel plot, the results were similar (pooled standardized mean difference = − 0.07 [95% confidence interval − 0.27 to 0.13]; I² = 0%; p = 0.49). Conclusions Creatine monohydrate supplementation was shown to be ineffective on endurance performance in a trained population. Clinical Trial Registration The study protocol was registered in the Prospective Register of Systematic Review (PROSPERO) with the following registration number: CRD42022327368.
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Vol.:(0123456789)
Sports Medicine (2023) 53:1017–1027
https://doi.org/10.1007/s40279-023-01823-2
SYSTEMATIC REVIEW
Effects ofCreatine Monohydrate onEndurance Performance
inaTrained Population: ASystematic Review andMeta‑analysis
JulenFernández‑Landa1,2 · AsierSantibañez‑Gutierrez1,2· NikolaTodorovic2· ValdemarStajer2·
SergejM.Ostojic2,3
Accepted: 8 February 2023 / Published online: 6 March 2023
© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023
Abstract
Background There is robust evidence that creatine monohydrate supplementation can enhance short-term high-intensity
exercise in athletes. However, the effect of creatine monohydrate supplementation on aerobic performance and its role during
aerobic activities is still controversial.
Objective The purpose of this systematic review and meta-analysis was to evaluate the supplementation effects of creatine
monohydrate on endurance performance in a trained population.
Methods The search strategy in this systematic review and meta-analysis was designed following Preferred Reporting Items
for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and PubMed/MEDLINE, Web of Science, and Scopus
databases were explored from inception until 19 May, 2022. Only human experimental trials, controlled with a placebo
group, evaluating the effects of creatine monohydrate supplementation on endurance performance in a trained population
were analyzed in this systematic review and meta-analysis. The methodological quality of included studies was evaluated
using the Physiotherapy Evidence Database (PEDro) scale.
Results A total of 13 studies satisfied all the eligibility criteria and were included in this systematic review and meta-
analysis. The results for the pooled meta-analysis showed a non-significant change in endurance performance after creatine
monohydrate supplementation in a trained population (p = 0.47), with a trivial negative effect (pooled standardized mean
difference = − 0.07 [95% confidence interval − 0.32 to 0.18]; I2 = 34.75%). Further, after excluding the studies not evenly
distributed around the base of the funnel plot, the results were similar (pooled standardized mean difference = − 0.07 [95%
confidence interval − 0.27 to 0.13]; I2 = 0%; p = 0.49).
Conclusions Creatine monohydrate supplementation was shown to be ineffective on endurance performance in a trained
population.
Clinical Trial Registration The study protocol was registered in the Prospective Register of Systematic Review (PROSPERO)
with the following registration number: CRD42022327368.
* Julen Fernández-Landa
julenfdl@hotmail.com
1 Physical Education andSports Department, Faculty
ofEducation andSport, University oftheBasque Country
(UPV/EHU), Vitoria, Spain
2 Applied Bioenergetics Lab, Faculty ofSport andPhysical
Education, University ofNovi Sad, NoviSad, Serbia
3 Department ofNutrition andPublic Health, University
ofAgder, Kristiansand, Norway
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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... Despite the growing popularity of creatine in endurance sports [19], evidence remains scarce and inconclusive. In fact, a recent meta-analysis including 13 studies found that creatine supplementation does not improve endurance performance [18]. It is worth noting, however, that the indicators used for the assessment of endurance performance Data are shown as mean ± SD. ...
... might play a major role. For instance, in the aforementioned meta-analysis Fernández-Landa et al. combined different indicators such as the lactate threshold-associated PO, time to exhaustion or VO 2max on an incremental test, or performance during a running, swimming or rowing TT [18]. Moreover, different populations were studied, including rugby, handball or soccer players, rowers, and swimmers [18]. ...
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... Our meta-analysis revealed a novel finding that Cr supplementation did not significantly affect 50 m time, 100 m time, or overall time in repeated interval swimming (Fig. 3). This result aligns with Fernández-Landa et al. (2023) meta-analyses, which indicated that Cr supplementation had no significant impact on endurance performance [45]. This might be due to Cr's action at the peripheral muscle level. ...
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Full-text available
  • Dec 2021
Although creatine supplementation is well-known to increase exercise performance in acute high-intensity exercises, its role in aerobic performance based on VO2max is more controversial. Thus, we performed a systematic review and meta-analysis on the effects of creatine supplementation on VO2max. PubMed, Cochrane, Embase, and ScienceDirect were searched for randomized controlled trials (RCTs) reporting VO2max in creatine supplementation and placebo groups before and after supplementation. We computed a random-effects meta-analysis on VO2max at baseline, within groups following supplementation, on changes on VO2max between groups, and after supplementation between groups. Sensitivity analyses and meta-regression were conducted. We included 19 RCTs for a total of 424 individuals (mean age 30 years old, 82% men). VO2max did not differ at baseline between groups (creatine and placebo). Participants in both groups were engaged in exercise interventions in most studies (80%). Using changes in VO2max, VO2max increased in both groups but increased less after creatine supplementation than placebo (effect size [ES] = −0.32, 95%CI = −0.51 to −0.12, p = 0.002). Comparisons after creatine supplementation confirmed a lower VO2max in the creatine group compared to the placebo group (ES= −0.20, 95%CI = −0.39 to −0.001, p = 0.049). Meta-analysis after exclusion from meta-funnel resulted in similar outcomes in a subgroup of young and healthy participants. Meta-regressions on characteristics of supplementation, physical training, or sociodemographic were not statistically significant. Creatine supplementation has a negative effect on VO2max, regardless of the characteristics of training, supplementation, or population.
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Effect of Ten Weeks of Creatine Monohydrate Plus HMB Supplementation on Athletic Performance Tests in Elite Male Endurance Athletes
Article
Full-text available
  • Jan 2020
Creatine monohydrate (CrM) and β-hydroxy β-methylbutyrate (HMB) are common ergogenic aids in the field of sports and are frequently used in an isolated way. However, there are a few studies that have investigated the effect of combining both supplements on different variables related to performance, with controversial results. Therefore, the main purpose of this study was to determine the efficacy and the degree of potentiation of 10 weeks of CrM plus HMB supplementation on sports performance, which was measured by an incremental test to exhaustion in elite male traditional rowers. In this placebo-controlled, double-blind trial, 10-week study, participants (n = 28) were randomized to a placebo group (PLG; n = 7), CrM group (0.04 g/kg/day of CrM; n = 7), HMB group (3 g/day of HMB; n = 7) and CrM-HMB group (0.04 g/kg/day of CrM plus 3 g/day of HMB; n = 7). Before and after 10 weeks of different treatments, an incremental test was performed on a rowing ergometer to calculate the power that each rower obtained at the anaerobic threshold (WAT), and at 4 mmol (W4) and 8 mmol (W8) of blood lactate concentration. There were no significant differences in WAT and W4 among groups or in body composition. However, it was observed that the aerobic power achieved at W8 was significantly higher in the CrM-HMB group than in the PLG, CrM and HMB groups (p < 0.001; η2p = 0.766). Likewise, a synergistic effect of combined supplementation was found for the sum of the two supplements separately at WAT (CrM-HMBG = 403.19% vs. CrMG+HMBG = 337.52%), W4 (CrM-HMBG = 2736.17% vs. CrMG+HMBG = 1705.32%) and W8 (CrM-HMBG = 1293.4% vs. CrMG+HMBG = 877.56%). In summary, CrM plus HMB supplementation over 10 weeks showed a synergistic effect on aerobic power (measured as WAT, W4, and W8) during an incremental test but had no influence muscle mass.
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Effect of the Combination of Creatine Monohydrate Plus HMB Supplementation on Sports Performance, Body Composition, Markers of Muscle Damage and Hormone Status: A Systematic Review
Article
Full-text available
  • Oct 2019
Although there are many studies showing the isolated effect of creatine monohydrate (CrM) and β-hydroxy β-methylbutyrate (HMB), it is not clear what effect they have when they are combined. The main purpose of this systematic review was to determine the efficacy of mixing CrM plus HMB in comparison with their isolated effects on sports performance, body composition, exercise induced markers of muscle damage, and anabolic-catabolic hormones. This systematic review was carried out in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement guidelines and the PICOS model, for the definition of the inclusion criteria. Studies were found by searching PubMed/MEDLINE, Web of Science (WOS), and Scopus electronic databases from inception to July 3rd 2019. Methodological quality and risk of bias were assessed by two authors independently, and disagreements were resolved by third-party evaluation, in accordance with the Cochrane Collaboration Guidelines samples. The literature was examined regarding the effects of the combination of CrM plus HMB on sport performance using several outcome variables (athletic performance, body composition, markers of muscle damage, and hormone status). This systematic review included six articles that investigated the effects of CrM plus HMB on sport performance (two on strength performance, showing improvements in one of them; three on anaerobic performance, presenting enhancements in two of them; and one on aerobic performance, not presenting improvements), body composition (three on body mass, showing improvements in one of them; two on fat free mass, presenting increases in one of them; and two on fat mass, showing decreases in one of them) and markers of muscle damage and hormone status (four on markers of muscle damage and one on anabolic-catabolic hormones, not showing benefits in any of them). In summary, the combination of 3-10 g/day of CrM plus 3 g/day of HMB for 1-6 weeks could produce potential positive effects on sport performance (strength and anaerobic performance) and for 4 weeks on body composition (increasing fat free mass and decreasing fat mass). However, this combination seems to not show positive effects relating to markers of exercise-induced muscle damage and anabolic-catabolic hormones.
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Acute Effects of Citrulline Supplementation on High-Intensity Strength and Power Performance: A Systematic Review and Meta-Analysis
Article
Full-text available
  • May 2019
  • SPORTS MED
Background Citrulline is an increasingly common dietary supplement that is thought to enhance exercise performance by increasing nitric oxide production. In the last 5 years, several studies have investigated the effects of citrulline supplements on strength and power outcomes, with mixed results reported. To date, the current authors are unaware of any attempts to systematically review this emerging body of literature. Objective The current study sought to conduct a systematic review and meta-analysis of the literature describing the effects of citrulline supplementation on strength and power outcomes. Methods A comprehensive, systematic search of three prominent research databases was performed to find peer-reviewed, English language, original research studies evaluating the effects of citrulline supplementation on indices of high-intensity exercise performance in healthy men and women. Outcomes included strength and power variables from performance tests involving multiple repetitive muscle actions of large muscle groups, consisting of either resistance training sets or sprints lasting 30 s or less. Tests involving isolated actions of small muscle groups or isolated attempts of single-jump tasks were not included for analysis due to differences in metabolic requirements. Studies were excluded from consideration if they lacked a placebo condition for comparison, were carried out in clinical populations, provided a citrulline dose of less than 3 g, provided the citrulline dose less than 30 min prior to exercise testing, or combined the citrulline ingredient with creatine, caffeine, nitrate, or other ergogenic ingredients. Results Twelve studies, consisting of 13 total independent samples (n = 198 participants), met the inclusion criteria. Between-study variance, heterogeneity, and inconsistency across studies were low (Cochrane’s Q = 6.9, p = 0.86; τ² = 0.0 [0.0, 0.08], I² = 0.0 [0.0, 40.0]), and no funnel plot asymmetry was present. Results of the meta-analysis identified a significant benefit for citrulline compared to placebo treatments (p = 0.036), with a small pooled standardized mean difference (SMD; Hedges’ G) of 0.20 (95% confidence interval 0.01–0.39). Conclusion The effect size was small (0.20), and confidence intervals for each individual study crossed the line of null effect. However, the results may be relevant to high-level athletes, in which competitive outcomes are decided by small margins. Further research is encouraged to fully elucidate the effects of potential moderating study characteristics, such as the form of citrulline supplement, citrulline dose, sex, age, and strength versus power tasks.
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Creatine monohydrate supplementation during eight weeks of progressive resistance training increases strength in as little as two weeks without reducing markers of muscle damage
Article
  • May 2018
  • J SPORT MED PHYS FIT
Background: Creatine supplementation (Cr) increases strength during resistance training, but the time course of this strength increase is unclear. The aim was to determine the precise time course by which Cr could increase strength and whether Cr prevents muscle damage during eight weeks of resistance training. Methods: Young males were randomized (double blind) to Cr (n=9, 0.07g/kg/d) and placebo (n=9) during 8-weeks of resistance training (3d/week). Strength was assessed across six exercises every two weeks. Venous blood samples obtained at baseline, and 24 and 48 hours after the final resistance training session were assessed for creatine kinase [CK] and lactate dehydrogenase [LDH] as measures of muscle damage. Results: Strength was significantly higher in the Cr versus placebo group (p<0.05) after two weeks of training for three of the six exercises (bench press, leg press, shoulder press). By the end of the eight weeks of training, strength was significantly higher in the Cr versus placebo group (p<0.05) for four of the six exercises (bench press, leg press, shoulder press, and triceps extension, but not biceps curl or lat-pulldown). Creatine supplementation did not prevent muscle damage. Indeed, muscle damage markers increased in the Cr compared to placebo group (p<0.05). Conclusions: Cr increased muscular strength in as little as two weeks during a resistance training program; however, this was not accompanied by decreased muscle damage. Greater muscle damage with Cr may be due to a greater training intensity enabled by Cr supplementation. This might lead to greater protein turnover and enhanced muscle adaptation.
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