Effect of branched-chain amino acid supplementation and exercise on quadriceps muscle quantity and quality in patients with cirrhosis as assessed by ultrasonography: A randomized controlled trial.

BACKGROUND/AIM: Sarcopenia and myosteatosis are common in patients with cirrhosis. The study aimed to evaluate efficacy of ultrasound to monitor muscle status during branched-chain amino acid (BCAA) supplementation and/or muscle exercise interventional approaches. PATIENTS AND METHODS: A randomized controlled study, included 220 liver cirrhosis patients with Child- Pugh B and C, randomized into a control group (55 patients) received only the standard care, and interventional groups (165 patients) equally distributed into three subgroups, in addition to standard care, they received BCAA, programmed exercise, or BCAA and programmed exercise. At baseline and after 28 days, all participants were subjected to ultrasound-measured quadriceps muscle thickness and echo-intensity, muscle strength using handgrip, performance using short physical performance battery (SPPB), Model for End-Stage Liver Disease (MELD) score and nutritional assessment using 7- point Subjective Global Assessment Score (SGA) and laboratory assessment. RESULTS: All interventional groups showed a significant improvement in the ultrasound detected quadriceps muscle thickness (p = 0.001) and echo intensity, in addition to muscle strength, muscle performance, and SGA. Hematological parameters (hemoglobin and platelet count), biochemical parameters (ALT, AST, bilirubin, creatinine, urea and INR) and MELD score were also improved in the interventional groups. In Child-Pugh B patients BCAA combined with exercise showed an add-on effect. CONCLUSION: BCAA supplements, programed muscle exercise and both are useful interventional methods in improving muscle quality and quantity in cirrhosis patients, which can be monitored by ultrasound. The best results can be achieved by combined intervention in Child-Pugh B, while in Child-Pugh C single intervention may lead to an acceptable improvement. The trial was registered retrospectively in the Clinical Trials Registry (registration number NCT06088550).

Home exercise, branched-chain amino acids, and probiotics improve frailty in cirrhosis: A randomized clinical trial.

BACKGROUND: Frailty is a predictive factor of hospitalization, falls, and mortality in patients with cirrhosis, regardless of the degree of liver failure. The aim was to analyze whether a multifactorial intervention consisting of home-based exercise, branched-chain amino acids, and a multistrain probiotic can improve frailty in these patients. METHODS: Outpatients with cirrhosis were classified according to the Liver Frailty Index (LFI). Prefrail and frail patients were randomized into 2 groups. The intervention group was assigned to a multifactorial intervention consisting of exercise at home, branched-chain amino acid supplements, and a multistrain probiotic for 12 months. The control group received standard care. All patients were prospectively followed up every 3 months for 1 year to determine LFI, incidence of falls, emergency room visits, hospitalizations, and mortality. RESULTS: Thirty-two patients were included: 17 patients were assigned to the intervention group and 15 to the control group. In the intervention group, the baseline LFI decreased at 3, 6, 9, and 12 months (p = 0.019 for overall change with respect to the control group). The change in LFI (ΔLFI) at 12 months was -0.71 ± 0.24 in the intervention group and -0.09 ± 0.32 in the control group (p<0.001). During follow-up, patients in the intervention group had a lower 1-year probability of falls (6% vs. 47%, p = 0.03) and emergency room visits (10% vs. 44%, p = 0.04) than patients in the control group. CONCLUSIONS: A long-term multifactorial intervention that included exercise at home, branched-chain amino acids, and a multistrain probiotic improved frailty in outpatients with cirrhosis and was associated with a decrease in the incidence of clinical events such as falls and emergency room visits.

Adding Branched-Chain Amino Acids and Vitamin D to Whey Protein Is More Effective than Protein Alone in Preserving Fat Free Mass and Muscle Strength in the First Month after Sleeve Gastrectomy.

OBJECTIVES: Sleeve gastrectomy (SG) is one of the most commonly performed weight loss (WL) bariatric procedures. The main goal of WL is reducing total body weight (TBW) and fat mass (FM). However, TBW loss is systematically accompanied by a decline in fat-free mass (FFM), predominantly in the first post-surgical month, despite protein supplementation. Branched-chain amino acids (BCAAs) and vitamin D seem to attenuate loss of FFM and, thus, reduce the decline in muscle strength (MS). However, data on the role of an integrated supplementation with whey protein plus BCAAs plus vitamin D (P+BCAAs+Vit.D) vs. protein alone on total weight loss (TWL), fat mass (FM), fat-free mass (FFM), and (MS) in the first month after SG are lacking. Therefore, the present study aims to evaluate the impact of P+BCAAs+Vit.D vs. protein alone supplementation on TWL, FM, FFM, and MS in the first month after SG. MATERIALS AND METHODS: Before SG and at 1 month afterward, we prospectively measured and compared TBW, FM, FFM, and MS in 57 patients who received either a supplementation with P+BCAAs+Vit.D (n = 31) or protein alone (n = 26). The impact of P+BCAAs+Vit.D and protein alone supplementation on clinical status was also evaluated. RESULTS: Despite non-significant variation in TBW, FM decreased more significantly (18.5% vs. 13.2%, p = 0.023) with the P+BCAA+Vit.D supplementation compared to protein alone. Furthermore, the P+BCAA+Vit.D group showed a significantly lower decrease in FFM (4.1% vs. 11.4%, p < 0.001) and MS (3.8% vs. 18.5%, p < 0.001) compared to the protein alone group. No significant alterations in clinical status were seen in either group. CONCLUSION: P+BCAA+Vit.D supplementation is more effective than protein alone in determining FM loss and is associated with a lower decrease in FFM and MS, without interfering with clinical status in patients 1 month after SG.

Branched-Chain Amino Acids Supplementation and Post-Exercise Recovery: An Overview of Systematic Reviews.

Objective: This overview of systematic reviews (OoSRs) aimed, firstly, to systematically review, summarize, and appraise the findings of published systematic reviews with or without meta-analyses that investigate the effects of branched-chain amino acids (BCAA) on post-exercise recovery of muscle damage biomarkers, muscle soreness, and muscle performance. The secondary objective was to re-analyze and standardize the results of meta-analyses using the random-effects Hartung-Knapp-Sidik-Jonkman (HKSJ) method.Methods: The methodological quality of the reviews was assessed using A Measurement Tool to Assess Systematic Reviews 2.We searched on five databases (i.e., PubMed, Web of Science, Scopus, SPORTDiscus, ProQuest) for systematic reviews with or without meta-analyses that investigated the effects of BCAA supplementation on the post-exercise recovery of muscle damage biomarkers, muscle soreness, and muscle performance.Results: Eleven systematic reviews (seven with meta-analyses) of individual studies were included. Evidence suggests BCAA ingestion attenuates creatine kinase (CK) levels (medium effects) and muscle soreness (small effects) immediately post-exercise and accelerates their recovery process, with trivial-to-large effects for CK levels and small-to-large effects for muscle soreness. BCAA supplementation has no effect on lactate dehydrogenase, myoglobin, and muscle performance recovery. The re-analyses with HKSJ method using the original data reported a slight change in results significance, concluding the same evidence as the original results. The major flaws found in the analyzed reviews were the absence of justification for excluding studies, and the lack of provision of sources of funding for primary studies and sources of conflict of interest and/or funding description.Conclusions: BCAA supplementation is an effective method to reduce post-exercise muscle damage biomarkers, particularly CK levels, and muscle soreness, with no effect on muscle performance. Future systematic reviews with/without meta-analyses, with greater methodological rigor, are needed.

This is the first overview of systematic reviews investigating the impact of BCAA supplementation on muscle damage biomarkers, muscle soreness, and muscle performance post-exercise recovery.BCAA supplementation reduces creatine kinase levels and muscle soreness, especially when consuming a high dose of BCAA longitudinally.BCAA supplementation has no effect on muscle performance post-exercise recovery.

Early administration of postoperative BCAA-enriched PPN may improve lean body mass loss in gastric cancer patients undergoing gastrectomy.

BACKGROUND: It has been reported that weight loss or lean body mass (LBM) loss after gastrectomy for gastric cancer is associated with prognosis and nutritional support alone is insufficient to prevent LBM loss. Branched-chain amino acids (BCAA) play an important role in muscle catabolism, however their clinical effects on suppression of LBM loss in gastric cancer patients undergoing gastrectomy remains elusive. In this current study, we investigated the effect of our original PPN regimen including BCAA (designated to BCAA-regimen) on LBM loss. METHODS: We conducted a randomized controlled trial (RCT) at a single institution where patients undergoing gastrectomy were assigned to either receive a five-day early postoperative course of the BCAA-regimen (BCAA group) or conventional nutrition. The primary endpoint was the % reduction in LBM at postoperative day 7. The secondary endpoints included the % reduction in LBM at 1 and 3 months postsurgery. RESULTS: At postoperative day 7, LBM loss in the BCAA group tended to be lower than in the control group (0.16% vs. 1.7%, respectively; P = 0.21), while at 1 month postsurgery, LBM loss in the BCAA group was significantly different to that of the control group (- 0.3% vs. 4.5%, respectively; P = 0.04). At 3 months postgastrectomy, however, LBM loss was similar between the BCAA and the control groups. CONCLUSION: Our RCT clinical trial clarified that early administration of the postoperative BCAA regimen improved LBM loss at 1 month after surgery in gastric cancer patients undergoing gastrectomy.

Sex-Specific Correlation Analysis of Branched-Chain Amino Acids in Dietary Intakes and Plasma among Chinese Adults.

BACKGROUND: Previous findings about the influence of dietary intakes of the branched-chain amino acid (BCAA) on their plasma concentrations have been limited and inconsistent, and evidence from the Chinese population was lacking. OBJECTIVES: This study aimed to investigate the diet-plasma BCAA correlations in Chinese male and female adults. METHODS: This cross-sectional study was based on a nested case-control study within 2 prospective population-based cohorts in Shanghai, China. Diet information was collected by the food frequency questionnaires. Plasma BCAA concentrations were measured by ultraperformance liquid chromatography coupled with tandem mass spectrometry. Spearman correlations and linear regression models were conducted to examine the relationships between dietary BCAA intakes and plasma BCAA. The multivariable model was adjusted for age at the interview, total energy intake, time of blood collection from last meal, dietary patterns, body mass index (in kg/m2), type 2 diabetes, and physical activity. RESULTS: A total of 322 males (median age of 57.0 y) and 187 females (median age of 60.0 y) were included in this cross-sectional study. The geometric means of dietary intake of leucine, isoleucine, valine, and BCAA were 4937.7, 3029.6, 3268.5, and 11237.4 mg/d in males, and 4125.7, 2567.8, 2754.3, and 9449.4 mg/d in females. The geometric means of plasma concentrations of leucine, isoleucine, valine, and BCAA were 181.9, 65.0, 219.8, and 469.4 µM/L in males and 161.6, 61.1, 206.5, and 431.6 µM/L in females. Only leucine (r = 0.1660, P = 0.0028) and total BCAA (r = 0.1348, P = 0.0155) in males exhibited weak positive correlation coefficients. After adjustment for the covariates, leucine, isoleucine, valine, and total BCAA in dietary intakes and plasma were not correlated in both males and females. CONCLUSIONS: In Chinese male and female adults, dietary intakes are not major determinants of plasma concentrations of BCAA, and plasma concentrations might not be reflected by usual dietary intakes of BCAA.

Changes in plasma concentration of kynurenine following intake of branched-chain amino acids are not caused by alterations in muscle kynurenine metabolism.

Administration of branched-chain amino acids (BCAA) has been suggested to enhance mitochondrial biogenesis, including levels of PGC-1α, which may, in turn, alter kynurenine metabolism. Ten healthy subjects performed 60 min of dynamic one-leg exercise at ∼70% of Wmax on two occasions. They were in random order supplied either a mixture of BCAA or flavored water (placebo) during the experiment. Blood samples were collected during exercise and recovery, and muscle biopsies were taken from both legs before, after, and 90 and 180 min following exercise. Ingestion of BCAA doubled their concentration in both plasma and muscle while causing a 30%-40% reduction (P < 0.05 vs. placebo) in levels of aromatic amino acids in both resting and exercising muscle during 3-h recovery period. The muscle concentration of kynurenine decreased by 25% (P < 0.05) during recovery, similar in both resting and exercising leg and with both supplements, although plasma concentration of kynurenine during recovery was 10% lower (P < 0.05) when BCAA were ingested. Ingestion of BCAA reduced the plasma concentration of kynurenic acid by 60% (P < 0.01) during exercise and recovery, whereas the level remained unchanged with placebo. Exercise induced a three- to fourfold increase (P < 0.05) in muscle content of PGC-1α1 mRNA after 90 min of recovery under both conditions, whereas levels of KAT4 mRNA and protein were unaffected by exercise or supplement. In conclusion, the reduction of plasma levels of kynurenine and kynurenic acid caused by BCAA were not associated with any changes in the level of muscle kynurenine, suggesting that kynurenine metabolism was altered in tissues other than muscle.

Branched Chain Amino Acid Supplementation to a Hypocaloric Diet Does Not Affect Resting Metabolic Rate but Increases Postprandial Fat Oxidation Response in Overweight and Obese Adults after Weight Loss Intervention.

BACKGROUND: Branched chain amino acids (BCAA) supplementation is reported to aid in lean mass preservation, which may in turn minimize the reduction in resting metabolic rate (RMR) during weight loss. Our study aimed to examine the effect of BCAA supplementation to a hypocaloric diet on RMR and substrate utilization during a weight loss intervention. METHODS: A total of 111 Chinese subjects comprising 55 males and 56 females aged 21 to 45 years old with BMI between 25 and 36 kg/m2 were randomized into three hypocaloric diet groups: (1) standard-protein (14%) with placebo (CT), (2) standard-protein with BCAA, and (3) high-protein (27%) with placebo. Indirect calorimetry was used to measure RMR, carbohydrate, and fat oxidation before and after 16 weeks of dietary intervention. RESULTS: RMR was reduced from 1600 ± 270 kcal/day to 1500 ± 264 kcal/day (p < 0.0005) after weight loss, but no significant differences in the change of RMR, respiratory quotient, and percentage of fat and carbohydrate oxidation were observed among the three diet groups. Subjects with BCAA supplementation had an increased postprandial fat (p = 0.021) and decreased postprandial carbohydrate (p = 0.044) oxidation responses compared to the CT group after dietary intervention. CONCLUSIONS: BCAA-supplemented standard-protein diet did not significantly attenuate reduction of RMR compared to standard-protein and high-protein diets. However, the postprandial fat oxidation response increased after BCAA-supplemented weight loss intervention.

Effects of Branched-chain Amino Acids on Nutritional Metabolism and Pharmacoeconomics in Patients with Severe Abdominal Trauma.

OBJECTIVE: To observe the influences of branched-chain amino acids (BCAAs) on nutrition metabolism and prognosis of patients with severe abdominal trauma; at the same time, to analyze and evaluate the pharmacoeconomics of it. METHODS: A total of 75 severe abdominal trauma patients were recruited from June 2016 to December 2017 and randomly divided into control group and observation group. After surgery and basic treatment, parenteral nutrition support therapy with iso-nitrogen and iso-calorie of both groups was administered. Meanwhile, an equivalent of 8.5% (18AA-II) and 10% (20AA) compound AA injection was administrated to the control and observation groups, respectively. The nitrogen balance, serum protein level and plasma amino spectrum of the patients were observed before and after treatment. Besides, the hospital stay, survival rate, complications, adverse reactions and hospitalization costs were also compared. RESULTS: After a 7-day course treatment, the nitrogen balance level of the two groups was significantly improved, but no significant difference was found between them. In addition, the serum protein level and plasma amino spectrum of the two groups was generally improved when compared to before treatment. Compared with the control group, the level of albumin and transferrin in the observation group was improved significantly after treatment, while no difference in plasma amino spectrum was found between the two groups. Moreover, the cost analysis showed remarkably reduced hospitalization costs in the observation group. CONCLUSION: To a certain degree, BCAAs could improve the nutritional metabolism and prognosis of patients with severe abdominal trauma, and have good cost-effectiveness.

The effect of branched-chain amino acid on muscle damage markers and performance following strenuous exercise: a systematic review and meta-analysis.

This systematic review and meta-analysis determined whether the ergogenic effects of branched-chain amino acids (BCAA) ameliorated markers of muscle damage and performance following strenuous exercise. In total, 25 studies were included, consisting of 479 participants (age 24.3 ± 8.3 years, height 1.73 ± 0.06 m, body mass 70.8 ± 9.5 kg, females 26.3%). These studies were rated as fair to excellent following the PEDro scale. The outcome measures were compared between the BCAA and placebo conditions at 24 and 48 hours following muscle-damaging exercises, using standardised mean differences and associated p-values via forest plots. Our meta-analysis demonstrated significantly lower levels of indirect muscle damage markers (creatine kinase, lactate dehydrogenase and myoglobin) at 48 hours post-exercise (standardised mean difference [SMD] = -0.41; p < 0.05) for the BCAA than placebo conditions, whilst muscle soreness was significant at 24 hours post-exercise (SMD = -0.28 ≤ d ≤ -0.61; p < 0.05) and 48 hours post-exercise (SMD = -0.41 ≤ d≤ -0.92; p < 0.01). However, no significant differences were identified between the BCAA and placebo conditions for muscle performance at 24 or 48 hours post-exercise (SMD = 0.08 ≤ d ≤ 0.21; p > 0.05). Overall, BCAA reduced the level of muscle damage biomarkers and muscle soreness following muscle-damaging exercises. However, the potential benefits of BCAA for muscle performance recovery is questionable and warrants further investigation to determine the practicality of BCAA for ameliorating muscle damage symptoms in diverse populations. PROSPERO registration number: CRD42020191248. Novelty: BCAA reduces the level of creatine kinase and muscle soreness following strenuous exercise with a dose-response relationship. BCAA does not accelerate recovery for muscle performance.

The use of BCAA to decrease delayed-onset muscle soreness after a single bout of exercise: a systematic review and meta-analysis.

Branched-chain amino acids (BCAA) are used as a recovery method after exercise-induced muscle damage (EIMD). Although data suggest that BCAA may alleviate the delayed-onset muscle soreness (DOMS) evoked by EIMD, there is no consensus about the most effective supplementation protocol. To investigate the effects of BCAA on DOMS after a single exercise session that caused EIMD, a systematic review and meta-analysis were conducted on the effectiveness of BCAA supplementation to reduce DOMS symptoms in healthy subjects after a single session of EIMD. Randomized clinical trials (RCT) were searched in Medline, Cochrane Library, Science Direct, SciELO, LILACS, SciVerse Scopus, Springer Link journals, Wiley Online Library, and Scholar Google, until May 2021. Ten RCTs were included in the systematic review and nine in the meta-analysis. Seven studies demonstrated that BCAA reduced DOMS after 24 to 72 h. BCAA doses of up to 255 mg/kg/day, or in trained subjects, for mild to moderate EIMD, could blunt DOMS symptoms. However, high variability between studies due to training status, different doses, time of treatment, and severity of EIMD do not allow us to conclude whether BCAA supplementation is efficient in untrained subjects, applied acutely or during a period of pre to post days of EIMD, and at higher doses (> 255 mg/kg/day). The overall effects of BCAA on DOMS after a single session of exercise were considered useful for improving muscle recovery by reducing DOMS in trained subjects, at low doses, in mild to moderate EIMD, and should not be administered only after the EIMD protocol.

Dietary Intake of Branched Chain Amino Acids and Breast Cancer Risk in the NHS and NHS II Prospective Cohorts.

Background: Branched chain amino acids (BCAAs) are essential amino acids common throughout the US diet. Although circulating BCAAs have been implicated in insulin resistance and some obesity-related cancers, the relationship between dietary intake of BCAAs and incident breast cancer is unknown. We sought to evaluate the association between long-term dietary intakes of BCAAs and invasive breast cancer risk. Methods: Our analyses included 196 161 women from the Nurses' Health Study and Nurses' Health Study II longitudinal cohorts. Average intakes of total and individual BCAAs (isoleucine, leucine, valine) were estimated from repeated diet questionnaires and incident self-reported breast cancer cases were confirmed via medical record review. Cox proportional hazards models, adjusted for reproductive history, lifestyle, body mass index, and other breast cancer risk factors, were used to estimate hazard ratios and 95% confidence intervals. Results: We observed 10 046 incident cases of breast cancer over a median of 20.8 years of follow-up. No associations between dietary intakes of total or individual BCAAs with breast cancer risk were observed. Compared with women in the bottom quintile of BCAA intake, the hazard ratio of breast cancer for those in the top quintile was 1.05 (95% confidence interval = 0.98 to 1.12; 2-sided P trend = .20). Findings were consistent across molecular subtypes and according to type 2 diabetes diagnosis and body mass index categories. Conclusions: Dietary intakes of BCAAs are not likely a risk factor for breast cancer.

Distribution of dietary protein intake in daily meals influences skeletal muscle hypertrophy via the muscle clock.

The meal distribution of proteins throughout the day is usually skewed. However, its physiological implications and the effects of better protein distribution on muscle volume are largely unknown. Here, using the two-meals-per-day feeding model, we find that protein intake at the early active phase promotes overloading-induced muscle hypertrophy, in a manner dependent on the local muscle clock. Mice fed branched-chain amino acid (BCAA)-supplemented diets at the early active phase demonstrate skeletal muscle hypertrophy. However, distribution-dependent effects are not observed in ClockΔ19 or muscle-specific Bmal1 knockout mice. Additionally, we examined the relationship between the distribution of proteins in meals and muscle functions, such as skeletal muscle index and grip strength in humans. Higher muscle functions were observed in subjects who ingested dietary proteins mainly at breakfast than at dinner. These data suggest that protein intake at breakfast may be better for the maintenance of skeletal muscle mass.

Leucine, but not isoleucine or valine, affects serum lipid profiles and browning of WAT in mice.

Branched chain amino acids (BCAA), especially leucine (Leu), have been reported to decrease fat deposition. However, opposite effects of BCAA on lipid metabolism have been observed. To determine the role of BCAA in lipid metabolism, an amino acid-defined diet was formulated and C57BL/6J mice were assigned into the following groups: amino acid-defined control diet and control diet supplemented with Leu, isoleucine, or valine. Nitrogen was balanced by proportionally mixed amino acids except BCAA. Results showed that dietary Leu supplementation significantly increased the levels of serum triglycerides, total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol and urea nitrogen. Metabolomics showed that biosynthesis of unsaturated fatty acids was altered by Leu supplementation. Leu treatment up-regulated the expression of genes related to fat synthesis and down-regulated the expression of genes related to fatty acid synthesis. Furthermore, the genes and proteins of selective markers involved in browning of white adipose tissue (WAT) were up-regulated by dietary supplementation with Leu. This study indicated that dietary supplementation with Leu, but not isoleucine or valine, significantly affected lipid metabolism by regulating lipid metabolism-related genes and serum fatty acid concentration, providing a new tool in the management of obesity and metabolic disorders.

The effect of multi-ingredient intra- versus extra-cellular buffering supplementation combined with branched-chain amino acids and creatine on exercise-induced ammonia blood concentration and aerobic capacity in taekwondo athletes.

BACKGROUND: This study aimed to investigate the effect of multi-ingredient intra- (BA) versus extra- (ALK) cellular buffering factor supplementation, combined with the customary intake of branched-chain amino acids (BCAA) and creatine malate (TCM), on body composition, exercise variables, and biochemical and hematological parameters in 9 elite taekwondo athletes. METHODS: Eight-week randomized double-blind crossover BA (5.0 g·day-1 of ß-alanine) versus ALK (0.07 g·kgFFM-1·day-1 of sodium bicarbonate) supplementation combined with BCAA (0.2 g·kgFFM-1·day-1) and TCM (0.05 g·kgFFM-1·day-1) during a standard 8-week taekwondo training period was implemented. In the course of the experiment, body composition (dual X-ray absorptiometry), aerobic capacity (ergospirometric measurements during an incremental treadmill test until exhaustion), and exercise blood biomarkers concentrations were measured. Data were analyzed using repeated measures within-between interaction analysis of variance with the inclusion of experimental supplementation order. RESULTS: The maximum post-exercise blood ammonia concentration decreased in both groups after supplementation (from 80.3 ± 10.6 to 72.4 ± 10.2 µmol∙L-1, p = 0.013 in BA; from 81.4 ± 8.7 to 74.2 ± 8.9 µmol∙L-1, p = 0.027 in ALK), indicating reduced exercise-related adenosine triphosphate degradation. However, no differences were found in body composition, aerobic capacity, blood lactate concentration, and hematological parameters after neither BA (combined with BCAA and TCM) nor ALK (combined with BCAA and TCM) supplementation. CONCLUSIONS: In highly trained taekwondo athletes, neither extra- nor intracellular buffering enhancement resulting from BA and ALK supplementation, combined with BCAA and TCM treatment, affects body mass and composition, maximum oxygen uptake, and hematological indices, even though certain advantageous metabolic adaptations can be observed.

Does Branched-Chain Amino Acids (BCAAs) Supplementation Attenuate Muscle Damage Markers and Soreness after Resistance Exercise in Trained Males? A Meta-Analysis of Randomized Controlled Trials.

Previous studies have reported the positive effects of branched-chain amino acids (BCAAs) supplementation on lowering plasma markers of muscle damage and subjective soreness after resistance exercise. However, a variety of factors can potentially moderate its efficacy. This meta-analysis aimed to summarize the evidence regarding the effect of BCAAs supplementation on plasma muscle damage markers and soreness after resistance exercise in only trained males, by considering the plasma lactate dehydrogenase (LDH) and creatine kinase (CK). Randomized controlled trials were identified through a computerized literature search for the period 2010-2020. The pooled data were analyzed with the random-effects model and heterogeneity using I2. Cochrane Collaboration tools was used for the assessment of risk of bias. Nine studies met the inclusion criteria. A positive effect was found for CK at <24, 24, and 48 h after exercise and for muscle soreness at <24 h only. However, the positive effect was not evident for plasma LDH at any follow-up time. Different outcomes for post-exercise responses may suggest that BCAAs supplementation can attenuate muscle damage and ameliorate muscle soreness after resistance exercise in trained males.

Higher Branched-Chain Amino Acid Intake Is Associated with Handgrip Strength among Korean Older Adults.

Sarcopenia is a disease of old age characterized by decreased muscle mass and strength. Branched-chain amino acids (BCAAs) promote muscle mass synthesis and increase muscle strength. We aimed to develop a dietary amino acid database and to examine the association between BCAA intake and handgrip strength in Korean older adults. Data from the Korea National Health and Nutrition Examination Survey 2014-2018 were used. Overall, 4852 participants aged ≥65 years were included in the study. Demographic, lifestyle, and health data were obtained through interviews and questionnaires. The 24-h recall method was used to assess dietary intake. An amino acid database was established using the 9th revision of the Korean Standard Food Composition Table. The mean handgrip strength was estimated from triplicate measurements obtained using the dominant hand. Multivariable linear regression analysis was performed to assess the association between BCAA intake and handgrip strength. Grains greatly contributed to amino acid intake; however, a significant negative association was observed between handgrip strength and increased BCAA intake through grains. In the fully adjusted model, leucine intake and handgrip strength showed a positive association. Thus, consuming BCAAs (especially leucine) via a variety of food sources can help maintain muscle health in older people.

Effect of Training-Detraining Phases of Multicomponent Exercises and BCAA Supplementation on Inflammatory Markers and Albumin Levels in Frail Older Persons.

Nowadays, it is accepted that the regular practice of exercise and branched-chain amino acids supplementation (BCAAs) can benefit the immune responses in older persons, prevent the occurrence of physical frailty (PF), cognitive decline, and aging-related comorbidities. However, the impact of their combination (as non-pharmacological interventions) in albumin and the inflammatory markers is not fully understood. Therefore, we investigated the effect of a 40-week multifactorial intervention [MIP, multicomponent exercise (ME) associated or not with BCAAs] on plasma levels of inflammatory markers and albumin in frail older persons (≥75 years old) living at residential care homes (RCH). This study consisted of a prospective, naturalistic, controlled clinical trial with four arms of multifactorial and experimental (interventions-wahshout-interventions) design. The intervention groups were ME + BCAAs (n = 8), ME (n = 7), BCAAs (n = 7), and control group (n = 13). Lower limb muscle-strength, cognitive profile, and PF tests were concomitantly evaluated with plasma levels of albumin, anti- and pro-inflammatory cytokines [Interleukin-10 (IL-10) and Tumor Necrosis Factor-alpha (TNF-α) respectively], TNF-α/IL-10 ratio, and myeloperoxidase (MPO) activity at four different time-points: Baseline (T1), after 16 weeks of multifactorial intervention (T2), then after a subsequent 8 weeks washout period (T3) and finally, after an additional 16 weeks of multifactorial intervention (T4). Improvement of cognitive profile and muscle strength-related albumin levels, as well as reduction in the TNF-α levels were found particularly in ME plus BCAAs group. No significant variations were observed over time for TNF-α/IL-10 ratio or MPO activity. Overall, the study showed that MIP triggered slight alterations in the inflammatory and physical function of the frail older participants, which could provide independence and higher quality of life for this population.

BCAA Supplementation in Mice with Diet-induced Obesity Alters the Metabolome Without Impairing Glucose Homeostasis.

Circulating branched chain amino acid (BCAA) levels are elevated in obese humans and genetically obese rodents. However, the relationship of BCAAs to insulin resistance in diet-induced obese mice, a commonly used model to study glucose homeostasis, is still ill-defined. Here we examined how high-fat high-sucrose (HFHS) or high-fat diet (HFD) feeding, with or without BCAA supplementation in water, alters the metabolome in serum/plasma and tissues in mice and whether raising circulating BCAA levels worsens insulin resistance and glucose intolerance. Neither HFHS nor HFD feeding raised circulating BCAA levels in insulin-resistant diet-induced obese mice. BCAA supplementation raised circulating BCAA and branched-chain α-keto acid levels and C5-OH/C3-DC acylcarnitines (AC) in muscle from mice fed an HFHS diet or HFD, but did not worsen insulin resistance. A set of short- and long-chain acyl CoAs were elevated by diet alone in muscle, liver, and white adipose tissue (WAT), but not increased further by BCAA supplementation. HFD feeding reduced valine and leucine oxidation in WAT but not in muscle. BCAA supplementation markedly increased valine oxidation in muscle from HFD-fed mice, while leucine oxidation was unaffected by diet or BCAA treatment. Here we establish an extensive metabolome database showing tissue-specific changes in mice on 2 different HFDs, with or without BCAA supplementation. We conclude that mildly elevating circulating BCAAs and a subset of ACs by BCAA supplementation does not worsen insulin resistance or glucose tolerance in mice. This work highlights major differences in the effects of BCAAs on glucose homeostasis in diet-induced obese mice versus data reported in obese rats and in humans.

Isolated Leucine and Branched-Chain Amino Acid Supplementation for Enhancing Muscular Strength and Hypertrophy: A Narrative Review.

Branched-chain amino acids (BCAA) are one of the most popular sports supplements, marketed under the premise that they enhance muscular adaptations. Despite their prevalent consumption among athletes and the general public, the efficacy of BCAA has been an ongoing source of controversy in the sports nutrition field. Early support for BCAA supplementation was derived from extrapolation of mechanistic data on their role in muscle protein metabolism. Of the three BCAA, leucine has received the most attention because of its ability to stimulate the initial acute anabolic response. However, a substantial body of both acute and longitudinal research has now accumulated on the topic, affording the ability to scrutinize the effects of BCAA and leucine from a practical standpoint. This article aims to critically review the current literature and draw evidence-based conclusions about the putative benefits of BCAA or leucine supplementation on muscle strength and hypertrophy as well as illuminate gaps in the literature that warrant future study.