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Background. Adequate protein ingestion-mediated stimulation of myofibrillar protein synthesis (MPS) is required to maintain skeletal muscle mass. It is currently unknown what per meal protein intake is required to maximally stimulate the response in older men and whether it differs from that of younger men. Methods. We retrospectively analyzed data from our laboratories that measured MPS in healthy older (~71 years) and younger (~22 years) men by primed constant infusion of l-ring-[13C6]phenylalanine after ingestion of varying amounts (0-40 g) of high-quality dietary protein as a single bolus and normalized to body mass and, where available, lean body mass (LBM). Results. There was no difference (p =. 53) in basal MPS rates between older (0.027±0.04%/h; means ± 95% CI) and young (0.028 ± 0.03%/h) men. Biphase linear regression and breakpoint analysis revealed the slope of first line segment was lower (p <. 05) in older men and that MPS reached a plateau after ingestion of 0.40 ± 0.19 and 0.24 ± 0.06 g/kg body mass (p =. 055) and 0.60 ± 0.29 and 0.25 ± 0.13 g/kg lean body mass (p <. 01) in older and younger men, respectively. Conclusions. This is the first report of the relative (to body weight) protein ingested dose response of MPS in younger and older men. Our data suggest that healthy older men are less sensitive to low protein intakes and require a greater relative protein intake, in a single meal, than young men to maximally stimulate postprandial rates of MPS. These results should be considered when developing nutritional solutions to maximize MPS for the maintenance or enhancement of muscle mass with advancing age. © 2014 © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: [email protected] /* */
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... Immediately after the exercise bout, the subjects ingested the assigned protein drink with either cricket protein, pea protein, or whey protein. Blood samples were obtained for 4 h following protein ingestion at seven fixed time points (20,40,60,90, 120, 180, 240 min). Sampling of six blood samples was unsuccessful, and in total, 394 blood samples were collected. ...
... All protein drinks contained 0.25 g protein per kilo fat free mass (FFM) dissolved in 400 mL water. This dose of protein was chosen since it corresponds to the dose of protein needed to stimulate MPS maximally in young males after a meal [20]. ...
... Another explanation could be that the stimulating effect of leucine and EAA on the mTOR signaling pathway and MPS for all protein sources have reached the upper level for stimulation. The current study and the study by Hermans et al. [17] enlighten that, at least in young men, traditional high-quality protein sources can be substituted with alternative proteins sources when the protein dose is sufficient to maximally stimulate MPS (~ 25-30 g/meal or ~ 0.25 g/kg FFM/meal) [20]. Nevertheless, attention to the decreased bioavailability of AA observed after the ingestion of the alternative protein sources (pea protein and cricket protein) may be of relevance if the protein intake is low or insufficient, e.g., in elderly and patients where maintenance of muscle mass and function is critical. ...
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PurposeNew dietary proteins are currently introduced to replace traditional animal protein sources. However, not much is known about their bioaccessibility and ability to stimulate muscle protein synthesis compared to the traditional protein sources. We aimed to compare effects of ingesting a protein bolus (0.25 g/kg fat free mass) of either cricket (insect), pea, or whey protein on circulating amino acid levels and activation of the mTORC1 signaling pathway in the skeletal muscle at rest and after exercise.Methods In a randomized parallel controlled trial, young males (n = 50) performed a one-legged resistance exercise followed by ingestion of one of the three protein sources. Blood samples were collected before and in the following 4 h after exercise. Muscle biopsies were obtained at baseline and after 3 h from the non-exercised and exercised leg.ResultsAnalysis of blood serum showed a significantly higher concentration of amino acids after ingestion of whey protein compared to cricket and pea protein. No difference between protein sources in activation of the mTORC1 signaling pathway was observed either at rest or after exercise.Conclusion Amino acid blood concentration after protein ingestion was higher for whey than pea and cricket protein, whereas activation of mTORC1 signaling pathway at rest and after exercise did not differ between protein sources.Trial registration numberClinicaltrials.org ID NCT04633694.
... As highlighted throughout, all previous studies [6,8,16] utilized cohorts of young participants ranging in average ages of 24-26 years of age. In this respect, "anabolic resistance" is a well-established phenomenon in the skeletal muscle of older adults whereby muscle protein synthesis is diminished in response to both resistance exercise [19] and protein ingestion [20,21]. While greater doses of protein can somewhat overcome the established resistance [20], this recommendation may not be pragmatic as eating patterns of aging populations clearly indicate a reduced ability to consume enough dietary protein, much less the increased amounts that are commonly recommended for this population [22]. ...
... In this respect, "anabolic resistance" is a well-established phenomenon in the skeletal muscle of older adults whereby muscle protein synthesis is diminished in response to both resistance exercise [19] and protein ingestion [20,21]. While greater doses of protein can somewhat overcome the established resistance [20], this recommendation may not be pragmatic as eating patterns of aging populations clearly indicate a reduced ability to consume enough dietary protein, much less the increased amounts that are commonly recommended for this population [22]. For these reasons, the need to examine the ability of co-ingesting a probiotic with dietary protein in an aging population is evident. ...
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Weizmannia coagulans GBI-30, 6086 (BC30) has previously been shown to increase protein digestion in an in vitro model of the stomach and small intestine and amino acid appearance in healthy men and women after ingestion of milk protein concentrate. The impact of ingesting BC30 with other protein sources or in other demographics is largely unknown. The purpose of this study was to examine the impact of adding BC30 to a 20-g dose of a blend of rice and pea protein on postprandial changes in blood amino acids concentrations in healthy, older women. Healthy, older females (n = 30, 58.5 ± 5.2 years, 165.4 ± 6.8 cm, 65.6 ± 8.8 kg, 23.7 ± 3.2 kg/m²) completed two separate 14-day supplementation protocols separated by a 3-week washout period. Participants were instructed to ingest a 20-g protein dose of a blend of rice and pea protein concentrates (ProDiem Plant Protein Solutions, Kerry) with (PPCBC30) or without (PPC) the addition of 1 × 10⁹ CFU BC30 (Kerry). Body composition and demographics were assessed upon arrival to the laboratory. Upon ingestion of their final assigned supplemental dose, blood samples were taken at 0 (baseline), 30-, 60-, 90-, 120-, 180-, and 240-min post-consumption and analyzed for amino acid concentrations. Alanine (p = 0.018), tryptophan (p = 0.003), cysteine (p = 0.041), essential amino acids (p = 0.050), and total amino acids (p = 0.039) all exhibited significantly (p ≤ 0.05) greater AUC with PPCBC30 when compared to PPC. In addition, tryptophan (p = 0.003), cysteine (p = 0.021), essential amino acids (p = 0.049), and total amino acids (p = 0.035) displayed significantly greater (p ≤ 0.05) concentration maximum (CMax) values in PPCBC30 when compared to PPC. Finally, time to reach CMax (TMax) was similar between conditions with 80% of all measured amino acids and amino acid combinations achieving CMax at a similar time (~ 60 min). Only phenylalanine TMax was found to be different (p = 0.01) between the two conditions with PPC displaying a greater proportion of TMax values after 30 min. Following qualitative (non-inferential) assessment, 88% of all measured outcomes achieved a higher AUC with PPCBC30 and 100% of all outcomes achieved a higher CMax with PPCBC30. In concert with previous findings in a younger mixed gender cohort with milk protein, the addition of BC30 to a daily 20-g dose of plant protein concentrate in healthy older women improved AUC and CMax values in several individual amino acids and amino acid combinations. Retrospectively registered on April 6, 2022, at ClinicalTrials.gov as NCT05313178.
... Protein is an essential muscle-building nutrient. It has been reported that older adults require more protein for muscle protein synthesis than younger adults; thus, it is clear that adequate protein intake is important for older adults (26,27) . The total amount of protein can be broadly divided into plant and animal sources. ...
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Objectives: As the world's population is ageing, improving the physical performance of the older population is becoming important. Although diets are fundamental to maintaining and improving physical performance, few studies have addressed the role of these factors in adults aged ≥85 years, and none have been conducted in Asia. This study aimed to determine the dietary patterns and examine their relationship with physical performance in this population. Design: This cross-sectional study (Kawasaki Aging and Wellbeing Project) estimated food consumption using a brief-type self-administered diet history questionnaire. The results were adjusted for energy after aggregating into 33 groups, excluding possible over- or underestimation. Principal component analysis was used to identify dietary patterns, and outcomes included hand grip strength, timed up-and-go test, and usual walking speed. Setting: This study was set throughout several hospitals in Kawasaki city. Participants: In total, 1,026 community-dwelling older adults (85-89 years) were enrolled. Results: Data of 1,000 participants (median age: 86.9 years, men: 49.9 %) were included in the analysis. Three major dietary patterns (DP1: various foods, DP2: red meats and coffee, DP3: bread and processed meats) were identified. The results of multiple regression analysis showed that the score of DP2 was negatively associated with hand grip strength (B, 95% confidence interval: -0.35, -0.64 to -0.06). Conclusions: This study suggests a negative association between hand grip strength and dietary patterns characterised by red meats and coffee in older adults aged ≥85 years in Japan.
... The intake of high levels of dietary protein is recognized as an effective strategy to prevent muscle decline in older adults. Older adults require more protein to stimulate muscle anabolism due to a decreased muscle protein synthesis [42]. In order to maintain metabolic homeostasis, older adults must consume more protein. ...
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Background: Soy foods contain high levels of soy protein or isoflavones, which can stimulate muscle protein synthesis and increase antioxidant capacity, and thus ameliorate muscle strength decline. However, data from epidemiological studies investigating the association of habitual soy food consumption with muscle strength decline among general Chinese adults are limited. Methods: This study included 29,525 participants (mean age: 41.6 years; 16,933 (53.8%) males). Soy food consumption was evaluated using a validated 100-item food frequency questionnaire. Handgrip strength (HGS) was assessed with a hand dynamometer. Analysis of covariance were performed to assess the multivariable-adjusted least square means (LSM) and 95% confidence interval (CI) for HGS. Results: The multiple adjusted LSM (95% CI) of HGS across soy food consumption were 35.5 (34.2, 37.1) kg for <1 time per week, 36.1 (34.6, 37.6) kg for 1 time per week, 36.3 (34.8, 37.8) kg for 2-3 times per week, and 36.6 (35.1, 38.0) kg for ≥4 times per week (p for trend < 0.001). Compared to participants with soy food consumption less than one time per week, the multiple adjusted odds ratio (95% CI) of low HGS was 0.638 (0.485, 0.836) when the weekly consumption was ≥ 4 times (p for trend < 0.01). Conclusions: Higher habitual soy food consumption was positively associated with HGS in general Chinese adults. Consumption of soy foods may have beneficial effects on muscle health.
... Associations between aging and anabolic resistance have been under investigation for decades and have indicated that a perturbed skeletal muscle anabolic response to a nutritional stimulus exists in aged individuals [55,56]. While basal skeletal muscle fractional synthetic rates have been shown to be similar between young and aged individuals [56][57][58][59], the sensitivity and responsiveness of MPS have been reported to be reduced in the elderly in response to hyperaminoacidemia [56,57,60]. This suggests that senescent muscle may require a relatively high concentration of amino acids [61] to mount an adequate anabolic response. ...
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Sarcopenia is a debilitating skeletal muscle disease that accelerates in the last decades of life and is characterized by marked deficits in muscle strength, mass, quality, and metabolic health. The multifactorial causes of sarcopenia have proven difficult to treat and involve a complex interplay between environmental factors and intrinsic age-associated changes. It is generally accepted that sarcopenia results in a progressive loss of skeletal muscle function that exceeds the loss of mass, indicating that while loss of muscle mass is important, loss of muscle quality is the primary defect with advanced age. Furthermore, preclinical models have suggested that aged skeletal muscle exhibits defects in cellular quality control such as the degradation of damaged mitochondria. Recent evidence suggests that a dysregulation of proteostasis, an important regulator of cellular quality control, is a significant contributor to the aging-associated declines in muscle quality, function, and mass. Although skeletal muscle target of rapamycin complex 1 (mTORC1) plays a critical role in cellular control, including skeletal muscle hypertrophy, paradoxically, sustained activation of mTORC1 recapitulates several characteristics of sarcopenia. Pharmaceutical inhibition of mTORC1 as well as caloric restriction significantly improves muscle quality in aged animals, however, the mechanisms controlling cellular proteostasis are not fully known. This information is important for developing effective therapeutic strategies that mitigate or prevent sarcopenia and associated disability. This review identifies recent and historical understanding of the molecular mechanisms of proteostasis driving age-associated muscle loss and suggests potential therapeutic interventions to slow or prevent sarcopenia.
... There is a well-established limitation on the quantity and quality of per-meal and total food intake for older adults [20], and the consensus on the importance of adjusting the diet, especially the supply of protein, for muscle health [21]. However, recommending protein supplementation as a stand-alone intervention for healthy older individuals seems ineffective in improving muscle mass and strength [22]. ...
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Japan has the world’s highest life longevity, and centenarian patients are no longer rare. However, sufficient information related to centenarians is not available. Herein, we report the case of a 101-year-old centenarian woman who recovered from extreme inactivity and general weakness, mainly through nutritional management at home, to understand instances of nutritional management in centenarians. The patient developed lethargy, with a rapid decline in activity levels and food intake. She was diagnosed with senility by a primary doctor. We concluded that she had no problems with feeding and swallowing and predicted that her motivation to eat had decreased. We planned an intervention that lasted three months. To reduce the risk of aspiration, we paid attention to her posture while eating. To stimulate her appetite, we increased the variety and color of food items. To consider both the texture of food and safety, we changed the form of foods from paste (IDDSI Level 4)-like to solid food of regular size as much as possible. We recommended that the patient consume her favorite sweet between meals to enjoy eating. Two and half months after the initial intervention, the patient’s inactivity and general weakness improved dramatically, which was recognized by her willingness to eat, laugh loudly, and hum, although she could not speak clearly. The patient finally was able to have dinner with her family.
... In the rested state, healthy older adults require ~0.4 g of protein/kg of body mass to maximise postprandial MPS and overcome anabolic resistance, wherein the anabolic MPS response to protein intake is blunted [37]. In contrast, young adults prompt a similar MPS response after approximately half of that dose [38]. Therefore, older adults require higher protein diets than younger adults to preserve muscle mass and function [39,40]. ...
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Plant-based proteins are generally characterised by lower Indispensable Amino Acid (IAA) content, digestibility, and anabolic properties, compared to animal-based proteins. However, they are environmentally friendlier, and wider consumption is advocated. Older adults have higher dietary protein needs to prevent sarcopenia, a disease marked by an accelerated loss of muscle mass and function. Given the lower environmental footprint of plant-based proteins and the importance of optimising dietary protein quality among older adults, this paper aims to assess the net peripheral Amino Acid (AA) appearance after ingestion of three different plant protein and fibre (PPF) products, compared to whey protein with added fibre (WPF), in healthy older adults. In a randomised, single-blind, crossover design, nine healthy men and women aged ≥65 years consumed four test meals balanced in AA according to the FAO reference protein for humans, matched for leucine, to optimally stimulate muscle protein synthesis in older adults. A fasted blood sample was drawn at each visit before consuming the test meal, followed by postprandial arterialise blood sampling every 30 min for 3 h. The test meal was composed of a soup containing either WPF or PPF 1-3. The PPF blends comprised pea proteins with varying additional rice, pumpkin, soy, oat, and/or almond protein. PPF product ingestion resulted in a lower maximal increase of postprandial leucine concentration and the sum of branched-chain AA (BCAA) and IAA concentrations, compared to WPF, with no effect on their incremental area under the curve. Plasma methionine and cysteine, and to a lesser extent threonine, appearance were limited after consuming the PPF products, but not WPF. Despite equal leucine doses, the WPF induced greater postprandial insulin concentrations than the PPF products. In conclusion, the postprandial appearance of AA is highly dependent on the protein source in older adults, despite providing equivalent IAA levels and dietary fibre. Coupled with lower insulin concentrations, this could imply less anabolic potential. Further investigation is required to understand the applicability of plant-based proteins in healthy older adults.
... In contrast, we have previously reported that protein ingestion may result in an attenuated rise in muscle protein synthesis rates in older when compared to young adult males [14]. However, this so-called "anabolic resistance" might be compensated for when ample amounts of protein (>20 g) are ingested [26,36,37]. As such, it could be speculated that the ingestion of 30 g high-quality protein in the current study was enough to elicit the same anabolic response in both young and older adult males despite the potential presence of some level of anabolic resistance in older adult males. ...
... Milk powders were stored at -20 • C prior to use. The volume of 650 mL was selected to align with previous studies investigating milk digestion dynamics (23), to provide a quantity of fat great enough to elicit a postprandial lipemic response [>20 g fat per serve (24)], and to provide a quantity of milk sufficient for the primary outcome of amino acid concentrations in circulation [>0.24 g/kg body weight of protein (25)], and the secondary outcome of lactose malabsorption [>250 mL milk (16)]. ...
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Background: Sheep milk (SM) is an alternate dairy source, which despite many similarities, has both compositional and structural differences in lipids compared to cow milk (CM). Studies are yet to examine the apparent digestibility of SM lipids, relative to CM, and the potential impact on the plasma lipidome. Objective: To determine the response of the circulatory lipidome to equal volume servings of SM and CM, in females who avoid dairy products. Method: In a double-blinded, randomized, cross-over trial, self-described dairy avoiding females (n=30; 24.4±1.1 years) drank SM or CM (650 mL; 33.4 vs. 21.3 g total lipid content; reconstituted from spray dried milk powders) following an overnight fast. Blood samples were collected at fasting and at regular intervals over 4 h after milk consumption. The plasma lipidome was analyzed by LC-MS and fatty acids were quantified by GC-FID. Results: The overall postprandial triglyceride (TG) response was similar between SM and CM. TG concentrations were comparable at fasting for both groups, however they were higher after CM consumption at 30 minutes (interaction milk × time p=0.003), well before any postprandial lipemic response. This was despite greater quantities provided by SM. However, there were notable differences in the postprandial fatty acid response, with SM leading to an increase in short- and medium-chain fatty acids (MUFAs)(C6:0, C8:0, C10:0) and several long-chain fatty acids (LCFAs) (C18:1 t11, c9,t11-CLA and C20:0; interaction time × milk p<0.05). This corresponded to a greater postprandial response for medium chain triglycerides (MCTs) C10:0, including TG(10:0/14:0/18:1),TG(16:0/10:0/12:0) and TG(16:0/10:0/14:0) (interaction time × milk p<0.05). Conclusions: Despite a higher fat content, SM ingestion resulted in a greater circulating abundance of MCTs, without increasing total postprandial triglyceride response, when compared to CM. The greater abundance and postprandial appearance of MCTs may provide advantageous metabolic responses in children and adults.
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New evidence shows that older adults need more dietary protein than do younger adults to support good health, promote recovery from illness, and maintain functionality. Older people need to make up for age-related changes in protein metabolism, such as high splanchnic extraction and declining anabolic responses to ingested protein. They also need more protein to offset inflammatory and catabolic conditions associated with chronic and acute diseases that occur commonly with aging. With the goal of developing updated, evidence-based recommendations for optimal protein intake by older people, the European Union Geriatric Medicine Society (EUGMS), in cooperation with other scientific organizations, appointed an international study group to review dietary protein needs with aging (PROT-AGE Study Group). To help older people (>65 years) maintain and regain lean body mass and function, the PROT-AGE study group recommends average daily intake at least in the range of 1.0 to 1.2 g protein per kilogram of body weight per day. Both endurance- and resistance-type exercises are recommended at individualized levels that are safe and tolerated, and higher protein intake (ie, ≥1.2 g/kg body weight/d) is advised for those who are exercising and otherwise active. Most older adults who have acute or chronic diseases need even more dietary protein (ie, 1.2-1.5 g/kg body weight/d). Older people with severe kidney disease (ie, estimated GFR <30 mL/min/1.73m(2)), but who are not on dialysis, are an exception to this rule; these individuals may need to limit protein intake. Protein quality, timing of ingestion, and intake of other nutritional supplements may be relevant, but evidence is not yet sufficient to support specific recommendations. Older people are vulnerable to losses in physical function capacity, and such losses predict loss of independence, falls, and even mortality. Thus, future studies aimed at pinpointing optimal protein intake in specific populations of older people need to include measures of physical function.
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The intake of whey, compared with casein and soy protein intakes, stimulates a greater acute response of muscle protein synthesis (MPS) to protein ingestion in rested and exercised muscle. We characterized the dose-response relation of postabsorptive rates of myofibrillar MPS to increasing amounts of whey protein at rest and after exercise in resistance-trained, young men. Volunteers (n = 48) consumed a standardized, high-protein (0.54 g/kg body mass) breakfast. Three hours later, a bout of unilateral exercise (8 × 10 leg presses and leg extensions; 80% one-repetition maximum) was performed. Volunteers ingested 0, 10, 20, or 40 g whey protein isolate immediately (∼10 min) after exercise. Postabsorptive rates of myofibrillar MPS and whole-body rates of phenylalanine oxidation and urea production were measured over a 4-h postdrink period by continuous tracer infusion of labeled [(13)C6] phenylalanine and [(15)N2] urea. Myofibrillar MPS (±SD) increased (P < 0.05) above 0 g whey protein (0.041 ± 0.015%/h) by 49% and 56% with the ingestion of 20 and 40 g whey protein, respectively, whereas no additional stimulation was observed with 10 g whey protein (P > 0.05). Rates of phenylalanine oxidation and urea production increased with the ingestion of 40 g whey protein. A 20-g dose of whey protein is sufficient for the maximal stimulation of postabsorptive rates of myofibrillar MPS in rested and exercised muscle of ∼80-kg resistance-trained, young men. A dose of whey protein >20 g stimulates amino acid oxidation and ureagenesis. This trial was registered at http://www.isrctn.org/ as ISRCTN92528122.
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Background: Protein is a macronutrient essential for growth, muscle function, immunity and overall tissue homeostasis. Suboptimal protein intake can significantly impact physical function and overall health in older adults. Methods: This article reviews the literature on the recommendations for protein intake in older adults in light of the new evidence linking protein intake with sarcopenia and physical function. Challenges and opportunities for optimal protein nutrition in older persons are discussed. Results: Recent metabolic and epidemiological studies suggest that the current recommendations of protein intake may not be adequate for maintenance of physical function and optimal health in older adults. Methodological limitations and novel concepts in protein nutrition are also discussed. Conclusion: We conclude that new research and novel research methodologies are necessary to establish the protein needs and optimal patterns of protein intake for older persons.
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We aimed to assess the reliability of the single biopsy approach for calculating muscle protein synthesis rates compared with the well described sequential muscle biopsy approach following a primed continuous infusion of L-[ring-(2)H(5)]phenylalanine and GC-MS analysis in older men. Two separate experimental infusion protocols, with differing stable isotope amino acid incorporation times, were employed consisting of n = 27 (experiment 1) or n = 9 (experiment 2). Specifically, mixed muscle protein FSR were calculated from baseline plasma protein enrichments and muscle protein enrichments obtained at 90 min or 50 min (1BX SHORT), 210 min or 170 min (1BX LONG), and between the muscle protein enrichments obtained at 90 and 210 min or 50 min and 170 min (2BX) of the infusion for experiments 1 and 2, respectively. In experiment 2, we also assessed the error that is introduced to the single muscle biopsy approach when nontracer naive subjects are recruited for participation in a primed continuous infusion of isotope-labeled amino acids. In experiment 1, applying the individual plasma protein enrichment values to the single muscle biopsy approach resulted in no differences in muscle protein FSR between the 1BX SHORT (0.031 ± 0.003%·h(-1)), 1BX LONG (0.032 ± 0.002%·h(-1)), or the 2BX approach (0.034 ± 0.002%·h(-1)). A significant correlation in muscle protein FSR was observed only between the 1BX LONG and 2BX approach (r = 0.8; P < 0.001). Similar results were observed in experiment 2. In addition, using the single biopsy approach in nontracer naïve state results in a muscle protein FSR that is negative for both the 1BX SHORT (-0.67 ± 0.051%·h(-1)) and 1BX LONG (-0.19 ± 0.051%·h(-1)) approaches. This is the first study to demonstrate that the single biopsy approach, coupled with the background enrichment of L-[ring-(2)H(5)]-phenylalanine of mixed plasma proteins, generates data that are similar to using the sequential muscle biopsy approach in the elderly population.