Oral Branched-Chain Amino Acids Supplementation in Athletes: A Systematic Review
Open accessAbstract
Branched-chain amino acids (BCAAs) are oxidized in the muscle and result in stimulating anabolic signals—which in return may optimize performance, body composition and recovery. Meanwhile, among athletes, the evidence about BCAA supplementation is not clear. The aim of this study was to review the effects of BCAAs in athletic populations. The research was conducted in three databases: Web of Science (all databases), PubMed and Scopus. The inclusion criteria involved participants classified both as athletes and people who train regularly, and who were orally supplemented with BCAAs. The risk of bias was individually assessed for each study using the revised Cochrane risk of bias tool for randomized trials (RoB 2.0). From the 2298 records found, 24 studies met the inclusion criteria. Although BCAAs tended to activate anabolic signals, the benefits on performance and body composition were negligible. On the other hand, studies that included resistance participants showed that BCAAs attenuated muscle soreness after exercise, while in endurance sports the findings were inconsistent. The protocols of BCAA supplements differed considerably between studies. Moreover, most of the studies did not report the total protein intake across the day and, consequently, the benefits of BCAAs should be interpreted with caution.
AI snapshot
Written from the paper’s full text.
TL;DR
This systematic review of 24 studies found that oral BCAA supplementation in athletes had negligible effects on performance and body composition, despite tending to activate anabolic signals. Benefits for muscle soreness/recovery were modality-dependent, with attenuation mainly in resistance exercise and inconsistent findings in endurance sports.
Key findings
- From 2298 records, 24 studies met inclusion criteria; BCAAs had trivial effects on performance outputs and negligible effects on body composition (e.g., comparable body weight changes after 7 days; negligible lean tissue and fat mass effects).
- In resistance participants, BCAA supplementation attenuated muscle soreness after exercise, and two studies reported attenuated performance decrements; in endurance sports, recovery/soreness findings were inconclusive (e.g., RPE and mental fatigue reduced in seven endurance cyclists, no RPE differences in 50 marathon runners, lower soreness in 16 distance runners).
- One 8-week hypocaloric resistance-training study reported BCAA increased upper-body strength (15.1 ± 2.2 kg) and lower-body strength (7.1 ± 1.6 kg), while the CHO group had negligible upper-body changes (4.8 ± 1.8 kg); a 10-week study in 18 cyclists found a group vs. time interaction for peak power and a higher BCAAs:tryptophan ratio with 20% and 4% increases in peak and mean power outputs, respectively.
- BCAA intake caused substantial improvement in the BCAAs:tryptophan ratio and immune response; hormonal changes indicated a favored anabolic response (cortisol decreased after exercise, testosterone tended to rise in resistance-training participants). Most studies did not report total daily protein intake.
Methods
- Systematic review following PRISMA and Cochrane guidance; databases Web of Science (all databases), PubMed, and Scopus were searched on 11 February 2022. Inclusion criteria: athletes or regular trainers, oral BCAA ingestion, outcomes on performance/body composition/recovery/biochemical/hormonal/molecular signaling, control or placebo, and pre- to post-test changes.
- 2298 records were identified; 649 duplicates were removed; 86 full texts were assessed; 24 studies were included. Data were extracted by two authors, and outcomes were categorized as performance, body composition, muscle soreness, recovery, and biochemical/hormonal/molecular indicators.
- Risk of bias was assessed individually with the revised Cochrane risk of bias tool for randomized trials (RoB 2.0) by two independent reviewers, with disagreements resolved by a third.
Limitations
- Stated in the paper: grey literature was not included; most original studies did not report total protein intake, especially per kilogram of body mass, so BCAA benefits should be interpreted cautiously; supplementation protocols varied widely in timing and quantity.
- Stated in the paper: risk-of-bias concerns included unclear randomization details, possible deviations from intended interventions in seven studies, and higher risk in outcome measurement in five studies.
- Evident from the text: several included studies had small samples (e.g., 7 endurance cyclists, 16 distance runners, 18 cyclists), and endurance findings were inconsistent, limiting generalizability.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
0 of 38 cited sources checked · 0 supported · 0 flagged
- Findingown data
Most included studies did not report total protein intake across the day.
“Moreover, most of the studies did not report the total protein intake across the day and, consequently, the benefits of BCAAs should be interpreted with caution.”
Quote in the paperSubstantial claim - Findingnone given
BCAAs tended to activate anabolic signals.
“Although BCAAs tended to activate anabolic signals, the benefits on performance and body composition were negligible.”
Quote in the paperSubstantial claim - Findingcitation
BCAA intake caused a substantial improvement in the BCAAs:tryptophan ratio.
“The main findings of these extracted studies reveal that BCAA intake caused a substantial improvement in BCAAs:tryptophan ratio [21,27] and immune response [27,38,39].”
Quote in the paperNot a substantial claim0 of 2 sources checked- cites [21] Blomstrand, 1997, Influence of ingesting a solution of branched-chain amino acids on perceived exertion during exercise, Acta Physiol. Scand. source
Not checked in the free run.
- cites [27] Kephart, 2016, Ten weeks of branched-chain amino acid supplementation improves select performance and immunological variables in trained cyclists, Amino Acids source
Not checked in the free run.
- Findingcitation
In 18 cyclists, long-term BCAA supplementation over 10 weeks produced a group vs. time interaction for peak power in the BCAA group.
“A separate study examining the effects of long-term BCAA supplementation over 10 weeks in 18 cyclists, found a group vs. time interaction for peak power in the BCAA group [27].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [27] Kephart, 2016, Ten weeks of branched-chain amino acid supplementation improves select performance and immunological variables in trained cyclists, Amino Acids source
Not checked in the free run.
- Findingcitation
Ratings of perceived exertion and mental fatigue were significantly reduced in the BCAA group among seven endurance cyclists.
“Ratings of perceived exertion and mental fatigue were significantly reduced in the BCAA group among seven endurance cyclists [21]”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [21] Blomstrand, 1997, Influence of ingesting a solution of branched-chain amino acids on perceived exertion during exercise, Acta Physiol. Scand. source
Not checked in the free run.
- Findingown data
BCAA supplementation has negligible or minimal impact on performance in athletes.
“Although BCAAs tended to activate anabolic signals, the benefits on performance and body composition were negligible.”
- Also stated in: § 4. Discussion · boosted
“It was demonstrated that BCAA supplementation has minimal impact on performance and negligible effects on body composition.”
- Also stated in: § 5. Conclusions · hedged
“The present review highlighted that BCAA supplementation does not appear to have a significant impact on performance.”
Quote in the paperSubstantial claim - Also stated in: § 4. Discussion · boosted
- Findingcitation
Two studies reported that BCAA supplementation attenuated decrements in performance.
“Two studies reported that the consumption of BCAA supplementation attenuated the decrements in performance [36,37].”
Quote in the paperNot a substantial claim0 of 2 sources checked- cites [36] Waldron, 2017, The effects of acute branched-chain amino acid supplementation on recovery from a single bout of hypertrophy exercise in resistance-trained athletes, Appl. Physiol. Nutr. Metab. source
Not checked in the free run.
- cites [37] VanDusseldorp, T.A., Escobar, K.A., Johnson, K.E., Stratton, M.T., Moriarty, T., Cole, N., McCormick, J.J., Kerksick, C.M., Vaughan, R.A., and Dokladny, K. (2018). Effect of Branched-Chain Amino Acid Supplementation on Recovery Following Acute Eccentric Exercise. Nutrients, 10. source
Not checked in the free run.
- Findingcitation
Comparable changes in body weight were observed in the BCAA and control groups after 7 days of oral supplementation.
“Comparable changes in body weight were observed in BCAAs and the control group after 7 days of oral supplementation [25].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [25] Areces, 2014, A 7-day oral supplementation with branched-chain amino acids was ineffective to prevent muscle damage during a marathon, Amino Acids source
Not checked in the free run.
- Findingreasoning
The effects of BCAAs on recovery and perceived muscle soreness were largely dependent on sport and exercise modality.
“The effects of BCAAs on recovery and perceived muscle soreness were largely dependent of sport and exercise modality.”
Quote in the paperSubstantial claim - Findingcitation
Negligible effects for the BCAA group were observed in lean tissue and fat mass.
“Negligible effects for the BCAA group were observed in lean tissue and fat mass [26,27].”
Quote in the paperSubstantial claim0 of 2 sources checked- cites [26] Dudgeon, 2016, In a single-blind, matched group design: Branched-chain amino acid supplementation and resistance training maintains lean body mass during a caloric restricted diet, J. Int. Soc. Sports Nutr. source
Not checked in the free run.
- cites [27] Kephart, 2016, Ten weeks of branched-chain amino acid supplementation improves select performance and immunological variables in trained cyclists, Amino Acids source
Not checked in the free run.
- Findingreasoning
Hormonal changes indicate that BCAA supplementation favored an anabolic hormonal response.
“Allowing for methodological variation between studies, the hormonal changes indicate that BCAA supplementation favored an anabolic hormonal response.”
Quote in the paperNot a substantial claim - Findingcitation
In studies including resistance participants, BCAAs attenuated muscle soreness after exercise.
“On the other hand, studies that included resistance participants showed that BCAAs attenuated muscle soreness after exercise, while in endurance sports the findings were inconsistent.”
- Also stated in: § 4. Discussion · hedged
“For endurance sports athletes, the results differed between studies while in resistance participants the BCAAs mostly attenuated muscle soreness.”
- Also stated in: § 3.3. Results of Individual Studies · hedged
“Studies that included resistance participants and examined the effects of BCAAs on muscle soreness or recovery indicated potential benefits of leucine, isoleucine or valine in the attenuation of muscle soreness after exercise [36,37].”
Quote in the paperSubstantial claim0 of 2 sources checked- cites [36] Waldron, 2017, The effects of acute branched-chain amino acid supplementation on recovery from a single bout of hypertrophy exercise in resistance-trained athletes, Appl. Physiol. Nutr. Metab. source
Not checked in the free run.
- cites [37] VanDusseldorp, T.A., Escobar, K.A., Johnson, K.E., Stratton, M.T., Moriarty, T., Cole, N., McCormick, J.J., Kerksick, C.M., Vaughan, R.A., and Dokladny, K. (2018). Effect of Branched-Chain Amino Acid Supplementation on Recovery Following Acute Eccentric Exercise. Nutrients, 10. source
Not checked in the free run.
- Also stated in: § 4. Discussion · hedged
- Findingcitation
Muscle soreness was lower in the BCAA group compared with the placebo trial of 16 distance runners.
“muscle soreness was lower in the BCAA group compared with the placebo trial of 16 distance runners [34].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [34] Koba, 2005, Effect of A Branched-chain Amino Acids Supplementation on Muscle Soreness during Intensive Training Program: 229: Board# 136: 11:00 AM–12:30 PM, Med. Sci. Sports Exerc.
Not checked in the free run.
- Findingcitation
Cortisol level decreased after exercise in participants that engaged in resistance training.
“The cortisol level decreased after exercise and, in parallel, testosterone tended to rise in participants that engaged in resistance training [3].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [3] Nemet, 2005, Proteins and amino acid supplementation in sports: Are they truly necessary?, Isr. Med. Assoc. J.
Not checked in the free run.
- Findingown data
The protocols of BCAA supplements differed considerably between studies.
“The protocols of BCAA supplements differed considerably between studies.”
- Also stated in: § 5. Conclusions · plain
“In the present review, supplementation protocols were widely variable in terms of timing and quantity, and this issue deserves particular attention in future research.”
Quote in the paperSubstantial claim - Also stated in: § 5. Conclusions · plain
- Findingown data
In endurance sports, findings on BCAA effects were inconsistent.
“while in endurance sports the findings were inconsistent.”
- Also stated in: § 4. Discussion · plain
“For endurance sports athletes, the results differed between studies while in resistance participants the BCAAs mostly attenuated muscle soreness.”
Quote in the paperSubstantial claim - Also stated in: § 4. Discussion · plain
- Findingcitation
In 50 marathon runners, no differences were reported in ratings of perceived exertion.
“while in 50 marathon runners no differences were reported in ratings of perceived exertion [25].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [25] Areces, 2014, A 7-day oral supplementation with branched-chain amino acids was ineffective to prevent muscle damage during a marathon, Amino Acids source
Not checked in the free run.
- Findingcitation
BCAA intake caused a substantial improvement in immune response.
“The main findings of these extracted studies reveal that BCAA intake caused a substantial improvement in BCAAs:tryptophan ratio [21,27] and immune response [27,38,39].”
Quote in the paperSubstantial claim0 of 3 sources checked- cites [27] Kephart, 2016, Ten weeks of branched-chain amino acid supplementation improves select performance and immunological variables in trained cyclists, Amino Acids source
Not checked in the free run.
- cites [38] Bassit, 2002, Branched-chain amino acid supplementation and the immune response of long-distance athletes, Nutrition source
Not checked in the free run.
- cites [39] Bassit, 2000, The effect of BCAA supplementation upon the immune response of triathletes, Med. Sci. Sports Exerc. source
Not checked in the free run.
- Findingown data
BCAA supplementation has negligible effects on body composition in athletes.
“Although BCAAs tended to activate anabolic signals, the benefits on performance and body composition were negligible.”
- Also stated in: § 4. Discussion · boosted
“It was demonstrated that BCAA supplementation has minimal impact on performance and negligible effects on body composition.”
Quote in the paperSubstantial claim - Also stated in: § 4. Discussion · boosted
- Findingcitation
Testosterone tended to rise in participants that engaged in resistance training.
“The cortisol level decreased after exercise and, in parallel, testosterone tended to rise in participants that engaged in resistance training [3].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [3] Nemet, 2005, Proteins and amino acid supplementation in sports: Are they truly necessary?, Isr. Med. Assoc. J.
Not checked in the free run.
- Findingreasoning
Oral ingestion of isolated BCAAs reduces muscle soreness.
“On the other hand, oral ingestion of isolated BCAAs reduces muscle soreness.”
Quote in the paperSubstantial claim - Premisecitation
Delayed onset muscle soreness was lower for the BCAA group than the placebo trial.
“Likewise, delayed onset muscle soreness was lower for the BCAA group than the placebo trial [10].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [10] Doma, 2021, The effect of branched-chain amino acid on muscle damage markers and performance following strenuous exercise: A systematic review and meta-analysis, Appl. Physiol. Nutr. Metab. source
Not checked in the free run.
- Study design and conductnone given
Interpretation of the second domain, deviations from intended interventions, in seven studies needs caution.
“The interpretation of the second domain—deviations from intended interventions—in seven studies [26,32,33,35,38,39,42] needs caution.”
Quote in the paperNot a substantial claim0 of 3 sources checked- cites [26] Dudgeon, 2016, In a single-blind, matched group design: Branched-chain amino acid supplementation and resistance training maintains lean body mass during a caloric restricted diet, J. Int. Soc. Sports Nutr. source
Not checked in the free run.
- cites [32] Pancar, 2020, The effect of Branched Chain Amino Acids Intake Before and after Exercise on Physical Performance and Recovery, Ambient. Sci.
Not checked in the free run.
- cites [33] Mor, 2022, The effects of BCAA and creatine supplementation on anaerobic capacity and ball kicking speed in male football players, J. Mens Health
Not checked in the free run.
- Premisenone given
Muscle damage markers (creatine kinase, lactate dehydrogenase and myoglobin) were lower at 24 and 48 hours post-exercise for the BCAA group than the placebo condition.
“Muscle damage markers (creatine kinase, lactate dehydrogenase and myoglobin) were lower at 24 and 48 post-exercise for the BCAA group than the placebo condition.”
Quote in the paperSubstantial claim - Premisecitation
A recent meta-analysis found that BCAAs had no significant effect on lactate dehydrogenase.
“A recent meta-analysis found that BCAAs had no significant effect on lactate dehydrogenase, while lower levels of creatine kinase were reported post-exercise in the BCAA group (<24 h; 24 h and 48 h).”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [10] Doma, 2021, The effect of branched-chain amino acid on muscle damage markers and performance following strenuous exercise: A systematic review and meta-analysis, Appl. Physiol. Nutr. Metab. source
Not checked in the free run.
- Study design and conductown data
In general, the included studies show a lower risk of bias for the five domains.
“In general, studies show a lower risk of bias for the five domains (see Figure 2).”
Quote in the paperNot a substantial claim - Study design and conductnone given
The 21 studies show a low risk of bias in the third and fifth domains.
“The 21 studies show a low risk of bias in the third and fifth domains.”
Quote in the paperNot a substantial claim - Premisecitation
Lower levels of creatine kinase were reported post-exercise in the BCAA group at <24 h, 24 h and 48 h.
“A recent meta-analysis found that BCAAs had no significant effect on lactate dehydrogenase, while lower levels of creatine kinase were reported post-exercise in the BCAA group (<24 h; 24 h and 48 h).”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [10] Doma, 2021, The effect of branched-chain amino acid on muscle damage markers and performance following strenuous exercise: A systematic review and meta-analysis, Appl. Physiol. Nutr. Metab. source
Not checked in the free run.
- Study design and conductcitation
Five studies demonstrated a higher risk of bias on the fourth domain concerning measurement outcome.
“On the fourth domain—concerning measurement outcome—five studies demonstrated a higher risk of bias [32,38,39,41].”
Quote in the paperNot a substantial claim0 of 3 sources checked- cites [32] Pancar, 2020, The effect of Branched Chain Amino Acids Intake Before and after Exercise on Physical Performance and Recovery, Ambient. Sci.
Not checked in the free run.
- cites [38] Bassit, 2002, Branched-chain amino acid supplementation and the immune response of long-distance athletes, Nutrition source
Not checked in the free run.
- cites [39] Bassit, 2000, The effect of BCAA supplementation upon the immune response of triathletes, Med. Sci. Sports Exerc. source
Not checked in the free run.
- Premisecitation
If an adequate intake of protein is ingested, the effects of BCAA on strength and hypertrophy are questioned.
“If an adequate intake of protein is ingested, the effects of BCAA on strength and hypertrophy are questioned [6].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [6] Plotkin, 2021, Isolated Leucine and Branched-Chain Amino Acid Supplementation for Enhancing Muscular Strength and Hypertrophy: A Narrative Review, Int. J. Sport Nutr. Exerc. Metab. source
Not checked in the free run.
- Study design and conductnone given
The details of randomization were not totally clarified in studies 31, 33, 38, 39, and 42.
“The details of randomization were not totally clarified in studies [31,33,38,39,42].”
Quote in the paperNot a substantial claim0 of 3 sources checked- cites [31] 2020, Short-term branched-chain amino acid supplementation does not enhance vertical jump in professional volleyball players. A double-blind, controlled, randomized study, Nutr. Hosp.
Not checked in the free run.
- cites [33] Mor, 2022, The effects of BCAA and creatine supplementation on anaerobic capacity and ball kicking speed in male football players, J. Mens Health
Not checked in the free run.
- cites [38] Bassit, 2002, Branched-chain amino acid supplementation and the immune response of long-distance athletes, Nutrition source
Not checked in the free run.
- Premisecitation
A significant heterogeneity between studies (75%) was observed 24 and 48 hours post-exercise.
“A significant heterogeneity between studies (75%) was observed 24- and 48-h post-exercise [10].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [10] Doma, 2021, The effect of branched-chain amino acid on muscle damage markers and performance following strenuous exercise: A systematic review and meta-analysis, Appl. Physiol. Nutr. Metab. source
Not checked in the free run.
- Classified as probably not a substantial claim. 6
- May combine two claims. 6
Probably not a substantial claim: may not pass S3 (load-bearing).
Findingown dataFrom 2298 records found, 24 studies met the inclusion criteria.
“From the 2298 records found, 24 studies met the inclusion criteria.”
Quote in the paperNot a substantial claimMay combine two claims.
FindingcitationIn a study of participants on a hypocaloric diet with heavy resistance training across 8 weeks, BCAA supplementation significantly increased upper and lower body strength, while the CHO group had negligible changes in upper body strength.
“The authors found that BCAA supplementation increased upper (15.1 ± 2.2 kg) and lower body strength (7.1 ± 1.6 kg), significantly, while the CHO group demonstrated negligible changes in upper body strength (4.8 ± 1.8 kg).”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [26] Dudgeon, 2016, In a single-blind, matched group design: Branched-chain amino acid supplementation and resistance training maintains lean body mass during a caloric restricted diet, J. Int. Soc. Sports Nutr. source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
InterpretationcitationThe role of carbohydrates on performance is crucial.
“By inference, the role of carbohydrates on performance is crucial [45].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [45] Jeukendrup, A., and Gleeson, M. (2018). Sport Nutrition, Human Kinetics. [3rd ed.].
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductown dataTwo independent authors screened titles and abstracts, and disagreements were resolved by a third author until consensus.
“Two independent authors (DVM/HS) screened the title and abstracts. The remaining manuscripts were assessed to check whether the eligibility criteria were met. Where disagreements occurred, a third author (AF) was consulted and debate ensued until a consensus was achieved.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductnone givenTwo independent observers completed the RoB 2.0 assessment and disagreements were solved by a third reviewer.
“Two independent observers completed the revised Cochrane risk of bias tool for randomized trials (DVM/HS) and possible disagreements were solved by a third reviewer (AF).”
Quote in the paperNot a substantial claimMay combine two claims.
InterpretationreasoningIt is plausible that the increase in BCAAs:tryptophan ratio reduced serotonin production and fatigue and subsequently improved performance.
“It is plausible to suggest that the increase in BCAAs:tryptophan ratio reduced the production of serotonin and fatigue and, subsequently, performance improved.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductcitationThe review was conducted according to PRISMA guidelines and Cochrane instructions.
“The current review was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines [16] and Cochrane instructions [17].”
Quote in the paperNot a substantial claim0 of 2 sources checked- cites [16] Page, 2021, PRISMA 2020 explanation and elaboration: Updated guidance and exemplars for reporting systematic reviews, BMJ source
Not checked in the free run.
- cites [17] Higgins, J.P., Thomas, J., Chandler, J., Cumpston, M., Li, T., Page, M.J., and Welch, V.A. (2019). Cochrane Handbook for Systematic Reviews of Interventions, John Wiley & Sons. source
Not checked in the free run.
May combine two claims.
InterpretationcitationWhen consumed during prolonged exercise, BCAAs increase the BCAAs:tryptophan ratio, confirming the central fatigue hypothesis.
“When consuming during prolonged exercise, BCAAs showed an increase in the BCAAs:tryptophan ratio, confirming the central fatigue hypothesis [49].”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [49] Newsholme, 2006, Branched-chain amino acids and central fatigue, J. Nutr. source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
Study design and conductnone givenRisk of bias was individually assessed for each study using the revised Cochrane risk of bias tool for randomized trials (RoB 2.0).
“The risk of bias was individually assessed for each study using the revised Cochrane risk of bias tool for randomized trials (RoB 2.0).”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [22] Sterne, 2019, RoB 2: A revised tool for assessing risk of bias in randomised trials, BMJ
Not checked in the free run.
The paper relies on this without support.
The effects of BCAA supplementation had previously been examined in non-sport participants or in samples combining athletes and active participants, leaving a need for a systematic review in athletes.
“The effects of BCAA supplementation were previously examined in non-sport participants or combining samples of athletes and active participants. Therefore, a systematic review about the impact of BCAAs among athletes is needed.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Leucine supplementation was not shown to significantly impact body composition and physical performance in humans.
“Despite these mechanistic insights, supplementation with leucin was not shown to significantly impact body composition and physical performance in humans [67].”
From Beyond Calories: Individual Metabolic and Hormonal Adaptations Driving Variability in Weight Management—A State-of-the-Art Narrative Review (2024) · cites this paper as [67]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Five higher-risk studies claimed but four cited
MinorThe fourth-domain assessment says five studies had a higher risk of bias but identifies only four studies in its accompanying citations.
“five studies demonstrated a higher risk of bias”
“[32,38,39,41]”
Body-composition study list omits a study named later
MinorThe study-characteristics section lists only studies [25] and [26] as examining body composition, whereas the individual-results section also names study [27].
“body composition [25,26]”
“The effectiveness of BCAA supplementation on body composition was examined in 50 amateur runners [25], 17 resistance athletes [26] and 18 cyclists [27].”
The citation lists haven’t been fetched yet
References 46 · Cited by 62
Research works printed but not linked: 3
- Koba, 2005, Effect of A Branched-chain Amino Acids Supplementation on Muscle Soreness during Intensive Training Program: 229: Board# 136: 11:00 AM–12:30 PM, Med. Sci. Sports Exerc., 37, S43
- Stipanuk, M.H., and Claudill, M.A. (2013). Biochemical, Physiological, and Molecular Aspects of Human Nutrition, Saunders.
- Atashak, 2014, Hormonal responses to acute resistance exercise after branched-chain amino acids supplementation, Int. Med. J., 22, 1
- Authors
- Martinho, D. V., Nobari, H., Faria, A., Field, A., Duarte, D., & Sarmento, H.
- Affiliations
- Universidade Politécnica de Coimbra (PT)
- Department of Physiology, Faculty of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain
- University of Huddersfield (GB)
- N2i—Polytechnic Institute of Maia, 4475-690 Maia, Portugal
- University of Coimbra (PT)
- Corresponding author
- Martinho, Diogo V.
- Venue
- Nutrients
- Publisher
- MDPI AG
- Published
- 2022-09-27
- Volume
- 14
- Issue
- 19
- Pages
- 4002
- ISSN
- 2072-6643 (ISSN-L)
- PMC
- PMC9571679
- OpenAlex
- W4297547857
- Cited by
- 62
- References
- 46
- Citations by year
- 2026: 14 · 2025: 25 · 2024: 17 · 2023: 6
- Type
- dissertation
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- Nutrients (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- e-space (Manchester Metropolitan University) (acceptedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Muscle metabolism and nutrition
- Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
- Health Sciences › Medicine › Physiology › Biochemical effects in animals
- Keywords
- branched-chain amino acids, BCAA supplementation, athletes, exercise performance, body composition, muscle soreness, resistance training, endurance training, anabolic signaling, recovery, protein intake
- MeSH terms
- Amino Acids, Branched-Chain, Humans, Exercise, Dietary Supplements, Athletes, Myalgia
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