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Antonio J, Evans C, Ferrando AA, Stout JR, Antonio B, Cinteo H, Harty P, Arent SM, Candow DG, Forbes SC, Kerksick CM, Pereira F, Gonzalez D, Kreider RB. Common questions and misconceptions about protein supplementation: what does the scientific evidence really show? J Int Soc Sports Nutr 2024; 21:2341903. [PMID: 38626029 PMCID: PMC11022925 DOI: 10.1080/15502783.2024.2341903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 04/07/2024] [Indexed: 04/18/2024] Open
Abstract
Protein supplementation often refers to increasing the intake of this particular macronutrient through dietary supplements in the form of powders, ready-to-drink shakes, and bars. The primary purpose of protein supplementation is to augment dietary protein intake, aiding individuals in meeting their protein requirements, especially when it may be challenging to do so through regular food (i.e. chicken, beef, fish, pork, etc.) sources alone. A large body of evidence shows that protein has an important role in exercising and sedentary individuals. A PubMed search of "protein and exercise performance" reveals thousands of publications. Despite the considerable volume of evidence, it is somewhat surprising that several persistent questions and misconceptions about protein exist. The following are addressed: 1) Is protein harmful to your kidneys? 2) Does consuming "excess" protein increase fat mass? 3) Can dietary protein have a harmful effect on bone health? 4) Can vegans and vegetarians consume enough protein to support training adaptations? 5) Is cheese or peanut butter a good protein source? 6) Does consuming meat (i.e., animal protein) cause unfavorable health outcomes? 7) Do you need protein if you are not physically active? 8) Do you need to consume protein ≤ 1 hour following resistance training sessions to create an anabolic environment in skeletal muscle? 9) Do endurance athletes need additional protein? 10) Does one need protein supplements to meet the daily requirements of exercise-trained individuals? 11) Is there a limit to how much protein one can consume in a single meal? To address these questions, we have conducted a thorough scientific assessment of the literature concerning protein supplementation.
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Affiliation(s)
- Jose Antonio
- Nova Southeastern University, Department of Health and Human Performance, Davie, FL, USA
| | - Cassandra Evans
- Nova Southeastern University, Department of Health and Human Performance, Davie, FL, USA
| | - Arny A. Ferrando
- University of Arkansas for Medical Sciences, Department of Geriatrics, Little Rock, AR, USA
| | - Jeffrey R. Stout
- University of Central Florida, School of Kinesiology and Rehabilitation Science, Orlando, FL, USA
| | - Brandi Antonio
- University of Central Florida, School of Kinesiology and Rehabilitation Science, Orlando, FL, USA
| | - Harry Cinteo
- Lindenwood University, Exercise and Performance Nutrition Laboratory, St. Charles, MO, USA
| | - Patrick Harty
- Lindenwood University, Exercise and Performance Nutrition Laboratory, St. Charles, MO, USA
| | - Shawn M. Arent
- University of South Carolina, Department of Exercise Science, Arnold School of Public Health, Columbia, SC, USA
| | - Darren G. Candow
- University of Regina, Faculty of Kinesiology and Health Studies, Regina, Canada
| | - Scott C. Forbes
- Brandon University, Department of Physical Education, Faculty of Education, Brandon, MB, Canada
| | - Chad M. Kerksick
- Lindenwood University, Exercise and Performance Nutrition Laboratory, St. Charles, MO, USA
| | - Flavia Pereira
- Keiser University, Exercise and Sport Science, West Palm Beach Flagship Campus, West Palm Beach, FL, USA
| | - Drew Gonzalez
- Texas A&M University, Exercise & Sport Nutrition Lab, Human Clinical Research Facility, Department of Health & Kinesiology, College Station, TX, USA
| | - Richard B. Kreider
- Texas A&M University, Exercise & Sport Nutrition Lab, Human Clinical Research Facility, Department of Health & Kinesiology, College Station, TX, USA
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Ruple BA, Vann CG, Sexton CL, Osburn SC, Smith MA, Godwin JS, Mumford PW, Stock MS, Roberts MD, Young KC. Peripheral quantitative computed tomography is a valid imaging technique for tracking changes in skeletal muscle cross-sectional area. Clin Physiol Funct Imaging 2024; 44:407-414. [PMID: 38666415 DOI: 10.1111/cpf.12885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 04/08/2024] [Accepted: 04/15/2024] [Indexed: 08/07/2024]
Abstract
Peripheral quantitative computed tomography (pQCT) has recently expanded to quantifying skeletal muscle, however its validity to determine muscle cross-sectional area (mCSA) compared to magnetic resonance imaging (MRI) is unknown. Eleven male participants (age: 22 ± 3 y) underwent pQCT and MRI dual-leg mid-thigh imaging before (PRE) and after (POST) 6 weeks of resistance training for quantification of mid-thigh mCSA and change in mCSA. mCSA agreement at both time points and absolute change in mCSA across time was assessed using Bland-Altman plots for mean bias and 95% limits of agreement (LOA), as well as Lin's concordance correlation coefficients (CCC). Both pQCT and MRI mCSA increased following 6 weeks of resistance training (∆mCSApQCT: 6.7 ± 5.4 cm2, p < 0.001; ∆mCSAMRI: 6.0 ± 6.4 cm2, p < 0.001). Importantly, the change in mCSA was not different between methods (p = 0.39). Bland-Altman analysis revealed a small mean bias (1.10 cm2, LOA: -6.09, 8.29 cm2) where pQCT tended to overestimate mCSA relative to MRI when comparing images at a single time point. Concordance between pQCT and MRI mCSA at PRE and POST was excellent yielding a CCC of 0.982. For detecting changes in mCSA, Bland-Altman analysis revealed excellent agreement between pQCT and MRI (mean bias: -0.73 cm2, LOA: -8.37, 6.91 cm2). Finally, there was excellent concordance between pQCT and MRI mCSA change scores (CCC = 0.779). Relative to MRI, pQCT imaging is a valid technique for measuring both mid-thigh mCSA at a single time point and mCSA changes following a resistance training intervention.
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Affiliation(s)
- Bradley A Ruple
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | - Christopher G Vann
- Duke Molecular Physiology Institute, Duke University School of Medicine, Duke University, Durham, North Carolina, USA
| | - Casey L Sexton
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | - Shelby C Osburn
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | - Morgan A Smith
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | - Joshua S Godwin
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | - Petey W Mumford
- Department of Kinesiology, Lindenwood University, St. Charles, Missouri, USA
| | - Matt S Stock
- School of Kinesiology and Physical Therapy, University of Central Florida, Orlando, Florida, USA
| | - Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
- Edward Via College of Osteopathic Medicine, Auburn, Alabama, USA
| | - Kaelin C Young
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
- College of Osteopathic Medicine, Pacific Northwest University of Health Sciences, Yakima, Washington, USA
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Medina-Vera I, Avila-Nava A, León-López L, Gutiérrez-Solis AL, Talamantes-Gómez JM, Márquez-Mota CC. Plant-based proteins: clinical and technological importance. Food Sci Biotechnol 2024; 33:2461-2475. [PMID: 39144188 PMCID: PMC11319542 DOI: 10.1007/s10068-024-01600-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 04/10/2024] [Accepted: 05/10/2024] [Indexed: 08/16/2024] Open
Abstract
Healthy and sustainable diets have seen a surge in popularity in recent years, driven by a desire to consume foods that not only help health but also have a favorable influence on the environment, such as plant-based proteins. This has created controversy because plant-based proteins may not always contain all the amino acids required by the organism. However, protein extraction methods have been developed due to technological advancements to boost their nutritional worth. Furthermore, certain chemicals, such as bioactive peptides, have been identified and linked to favorable health effects. As a result, the current analysis focuses on the primary plant-based protein sources, their chemical composition, and the molecular mechanism activated by the amino acid types of present. It also discusses plant protein extraction techniques, bioactive substances derived from these sources, product development using plant protein, and the therapeutic benefits of these plant-based proteins in clinical research.
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Affiliation(s)
- Isabel Medina-Vera
- Departamento de Metodología de la Investigación, Instituto Nacional de Pediatría (INP), Mexico City, Mexico
| | - Azalia Avila-Nava
- Hospital Regional de Alta Especialidad de la Península de Yucatán, Mérida, Mexico
| | - Liliana León-López
- Programa de Posgrado Integral en Biotecnología, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Sinaloa, C.P. 80000 Culiacán, Sinaloa Mexico
| | | | - José Moisés Talamantes-Gómez
- Departamento de Nutrición Animal y Bioquímica, Facultad de Medicina Veterinaria y Zootecnia (FMVZ), Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Claudia C. Márquez-Mota
- Departamento de Nutrición Animal y Bioquímica, Facultad de Medicina Veterinaria y Zootecnia (FMVZ), Universidad Nacional Autónoma de México, Mexico City, Mexico
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Smith KS, Morris MM, Morrow CD, Novak JR, Roberts MD, Frugé AD. Mood disturbance, but not overall diet quality, is associated with fecal microbiome diversity in free-living adults. Nutr Neurosci 2024; 27:451-459. [PMID: 37183583 DOI: 10.1080/1028415x.2023.2213484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
OBJECTIVES To investigate the gut-brain axis, we explored the relationships among mood disturbance (MD), diet quality (DQ), and fecal microbiota in free-living adults. METHODS A cross-sectional analysis was conducted with data from 75 healthy adults enrolled in two studies. Anthropometrics, 16s rRNA gene sequencing of fecal microbes, DQ as assessed by Healthy Eating Index-2015 (HEI), and MD determined by Profile of Mood States (POMS) were included. Alpha-diversity and DQ differences were explored between low (n = 37) and high MD (n = 38) groups. Spearman correlations were used to investigate relationships between alpha-diversity, DQ, and POMS subscales. Moderation analysis explored the effect of HEI score on the relationship between MD and alpha-diversity. RESULTS Participants were mostly white (67%), 54.5 years old (±11.8), and overweight (28.5 ± 6.5 kg/m2). Shannon and Simpson indices indicate higher alpha-diversity in participants with low MD compared to high MD (p = 0.004 and p = 0.008, respectively). Simpson and Shannon indices were correlated with subscale of anger (rho = -0.303, p = 0.011; rho = -0.265, p = 0.027, respectively)and total MD (rho = -0.404, p = 0.001; rho = -0.357, p = 0.002, respectively). Refined grains were associated with fatigue and tension subscales (rho = 0.428, p < 0.001; rho = 0.302, p = 0.014, respectively). DQ did not significantly moderate the relationship between alpha-diversity and mood disturbance (F(7, 53) = 2.00, p = 0.072, R2 = 0.209). Shannon index was a significant predictor of MD (b = -4.39, t(53) = -2.55, p = 0.014), but total HEI score and the interaction (Shannon index*HEI score) were not significant. DISCUSSION Greater bacterial diversity was associated with lower MD, and DQ was associated with various mood state subscales in this sample of adults.
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Affiliation(s)
- Kristen S Smith
- Department of Nutritional Sciences, Auburn University, Auburn, AL, USA
| | - Molly M Morris
- College of Science and Mathematics, Auburn University, Auburn, AL, USA
| | - Casey D Morrow
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Josh R Novak
- Department of Human Development and Family Science, Auburn University, Auburn, AL, USA
| | | | - Andrew D Frugé
- Department of Nutritional Sciences, Auburn University, Auburn, AL, USA
- College of Nursing, Auburn University, Auburn, AL, USA
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Liao CD, Huang SW, Chen HC, Huang MH, Liou TH, Lin CL. Comparative Efficacy of Different Protein Supplements on Muscle Mass, Strength, and Physical Indices of Sarcopenia among Community-Dwelling, Hospitalized or Institutionalized Older Adults Undergoing Resistance Training: A Network Meta-Analysis of Randomized Controlled Trials. Nutrients 2024; 16:941. [PMID: 38612975 PMCID: PMC11013298 DOI: 10.3390/nu16070941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/20/2024] [Accepted: 03/22/2024] [Indexed: 04/14/2024] Open
Abstract
Aging-related sarcopenia exerts harmful impacts on muscle mass, strength, and physical mobility. Protein supplementation has been demonstrated to augment efficacy of resistance training (RT) in elderly. This study compared the relative effects of different protein supplements on muscle mass, strength, and mobility outcomes in middle-aged and older individuals undergoing RT. A comprehensive search of online databases was performed to identify randomized controlled trials (RCTs) examining the efficacy of protein supplement plus RT in untrained community-dwelling adults, hospitalized, or institutionalized residents who suffered acute or chronic health conditions. Network meta-analysis (NMA) was performed using a frequentist method for all analyses. Treatment effects for main outcomes were expressed as standard mean difference (SMD) with 95% confidence interval (CI). We used the surface-under-the cumulative-ranking (SUCRA) scores to rank probabilities of effect estimation among all identified treatments. Meta-regression analyses were performed to identify any relevant moderator of the treatment efficacy and results were expressed as β with 95% credible interval (CrI). We finally included 78 RCTs (5272 participants) for analyses. Among the six protein sources identified in this NMA, namely whey, milk, casein, meat, soy, and peanut, whey supplement yielded the most effective treatments augmenting efficacy of RT on muscle mass (SMD = 1.29, 95% CI: 0.96, 1.62; SUCRA = 0.86), handgrip strength (SMD = 1.46, 95% CI: 0.92, 2.00; SUCRA = 0.85), and walking speed (SMD = 0.73, 95% CI: 0.39, 1.07; SUCRA = 0.84). Participant's health condition, sex, and supplementation dose were significant factors moderating the treatment efficacy on muscle mass (β = 0.74; 95% CrI: 0.22, 1.25), handgrip strength (β = -1.72; 95% CrI: -2.68, -0.77), and leg strength (β = 0.76; 95% CrI: 0.06, 1.47), respectively. Our findings suggest whey protein yields the optimal supplements to counter sarcopenia in older individuals undergoing RT.
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Affiliation(s)
- Chun-De Liao
- International Ph.D. Program in Gerontology and Long-Term Care, College of Nursing, Taipei Medical University, New Taipei City 110301, Taiwan;
- Department of Physical Medicine and Rehabilitation, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235041, Taiwan; (S.-W.H.); (H.-C.C.); (T.-H.L.)
| | - Shih-Wei Huang
- Department of Physical Medicine and Rehabilitation, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235041, Taiwan; (S.-W.H.); (H.-C.C.); (T.-H.L.)
- Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, New Taipei City 110301, Taiwan
| | - Hung-Chou Chen
- Department of Physical Medicine and Rehabilitation, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235041, Taiwan; (S.-W.H.); (H.-C.C.); (T.-H.L.)
- Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, New Taipei City 110301, Taiwan
| | - Mao-Hua Huang
- Department of Biochemistry, University of Washington, Seattle, WA 98015, USA;
| | - Tsan-Hon Liou
- Department of Physical Medicine and Rehabilitation, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235041, Taiwan; (S.-W.H.); (H.-C.C.); (T.-H.L.)
- Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, New Taipei City 110301, Taiwan
| | - Che-Li Lin
- Department of Orthopedic Surgery, Shuang Ho Hospital, Taipei Medical University, New Taipei City 23561, Taiwan
- Department of Orthopedics, School of Medicine, College of Medicine, Taipei Medical University, New Taipei City 11031, Taiwan
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6
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Protein Supplementation for Strength and Functionality in Older Adults: Is There Still Any Doubt? A Brief Update Review. J Aging Phys Act 2022; 31:311-318. [PMID: 35940583 DOI: 10.1123/japa.2022-0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/17/2022] [Accepted: 06/21/2022] [Indexed: 11/18/2022]
Abstract
It is widely known that the aging process induces relevant impairments on both muscle morphology and function. In this sense, resistance training alongside proper protein intake are important strategies to mitigate the sarcopenia process in older individuals. However, adding protein supplementation (PS) to resistance training interventions for enhancing muscle strength and functional performance has shown mixed results in this population. Therefore, the present study aimed to review the most recent evidence regarding PS and its effects on muscle strength and functional parameters of older adults. In addition, the effect size of each individual study (post-pre intervention) was also calculated to provide further clinical relevance on the topic. The results of the studies included do not seem to support PS for healthy older adults with proper protein intake. However, further studies with other sample characteristics (very old, frail, obese, and inadequate protein consumption) must be carried out to better understand the effects of PS in an older population.
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Michel JM, Lievense KK, Norton SC, Costa JV, Alphin KH, Bailey LA, Miller GD. The Effects of Graded Protein Intake in Conjunction with Progressive Resistance Training on Skeletal Muscle Outcomes in Older Adults: A Preliminary Trial. Nutrients 2022; 14:nu14132739. [PMID: 35807922 PMCID: PMC9268432 DOI: 10.3390/nu14132739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/27/2022] [Accepted: 06/29/2022] [Indexed: 01/25/2023] Open
Abstract
Many studies have evaluated the effects of resistance training (RT) and protein intake to attenuate the age-related loss of skeletal muscle. However, the effects of graded protein intake with conjunctive RT in older adults are unclear. Older adults (n = 18) performed 10 weeks of whole-body RT with progressions to intensity and volume while consuming either a constant protein (CP) diet (0.8−1.0 g/kg/d) with no protein supplement or a graded protein (GP) diet progressing from 0.8 g/kg/d at week 1 to 2.2 g/kg/d at week 10 with a whey protein supplement. Data were collected prior to commencement of the RT protocol (PRE), after week 5 (MID), and after week 10 (POST). Dual Energy X-ray Absorptiometry derived lean/soft tissue mass, ultrasonography derived muscle thickness, and a proxy of muscle quality were taken at PRE and POST, while isokinetic dynamometry derived peak torque were taken at PRE, MID, and POST. This study demonstrated the feasibility of the RT protocol (attendance = 96%), and protein intake protocol (CP in range all weeks; GP deviation from prescribed = 7%). Peak torque, muscle quality scores, and appendicular lean/soft tissue mass demonstrated the main effects of time (p < 0.05) while no other main effects of time or group * time interactions were seen for any measure. In conclusion, RT improved appendicular lean/soft tissue mass, peak torque, and muscle quality, with no differential effects of graded or constant protein intake.
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Affiliation(s)
- J. Max Michel
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA; (J.M.M.); (K.K.L.); (S.C.N.); (J.V.C.); (K.H.A.); (L.A.B.)
| | - Kristy K. Lievense
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA; (J.M.M.); (K.K.L.); (S.C.N.); (J.V.C.); (K.H.A.); (L.A.B.)
| | - Sam C. Norton
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA; (J.M.M.); (K.K.L.); (S.C.N.); (J.V.C.); (K.H.A.); (L.A.B.)
| | - Juliana V. Costa
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA; (J.M.M.); (K.K.L.); (S.C.N.); (J.V.C.); (K.H.A.); (L.A.B.)
| | - Kathryn H. Alphin
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA; (J.M.M.); (K.K.L.); (S.C.N.); (J.V.C.); (K.H.A.); (L.A.B.)
| | - Lydia A. Bailey
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA; (J.M.M.); (K.K.L.); (S.C.N.); (J.V.C.); (K.H.A.); (L.A.B.)
| | - Gary D. Miller
- Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC 27106, USA; (J.M.M.); (K.K.L.); (S.C.N.); (J.V.C.); (K.H.A.); (L.A.B.)
- Translational Science Center, Wake Forest University, Winston-Salem, NC 27106, USA
- Correspondence: ; Tel.: +1-336-758-1901
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Nichele S, Phillips SM, Boaventura BC. Plant-based food patterns to stimulate muscle protein synthesis and support muscle mass in humans: a narrative review. Appl Physiol Nutr Metab 2022; 47:700-710. [PMID: 35508011 DOI: 10.1139/apnm-2021-0806] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The interest in a diet with a higher proportion of plant-based foods to animal-based foods is a global food pattern trend. However, there are concerns regarding adopting plants as the main dietary protein source to support muscle protein synthesis and muscle mass. These concerns are centred on three issues: lower protein bioavailability due to antinutritional compounds in plants, lower per-serve scores of protein at similar energy intake, and amino acid scores of plants being lower than optimal. We aimed here to synthesize and discuss evidence around plant protein in human nutrition focusing on the capacity of these proteins to stimulate muscle protein synthesis as a key part of gaining or maintaining muscle mass. In this review, we address the issues of plant protein quality and provide evidence for how plant proteins can be made more effective to stimulate muscle protein synthesis and support muscle mass in partial or total replacement of consumption of products of animal origin. Novelty: ● Plant proteins are known, in general, to have lower protein quality scores than animal proteins, and this may have important implications, especially for those aiming to increase their skeletal muscle mass through exercise. ● A plant-based diet has been postulated to have lower protein quality limiting MPS responses and potentially compromising exercise-induced gains in muscle mass. ● Current evidence shows that plant proteins can stimulate MPS, as can whole foods, especially when combining food groups, increasing portion sizes, and optimizing amino acid bioavailability through processing or common preparation methods.
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Affiliation(s)
- Sarah Nichele
- Federal University of Santa Catarina, 28117, Nutrition, Florianopolis, Brazil;
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9
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Moore JH, Smith KS, Chen D, Lamb DA, Smith MA, Osburn SC, Ruple BA, Morrow CD, Huggins KW, McDonald JR, Brown MD, Young KC, Roberts MD, Frugé AD. Exploring the Effects of Six Weeks of Resistance Training on the Fecal Microbiome of Older Adult Males: Secondary Analysis of a Peanut Protein Supplemented Randomized Controlled Trial. Sports (Basel) 2022; 10:sports10050065. [PMID: 35622473 PMCID: PMC9145250 DOI: 10.3390/sports10050065] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/14/2022] [Accepted: 04/18/2022] [Indexed: 01/04/2023] Open
Abstract
The bacteria inhabiting the gastrointestinal tract contribute to numerous host functions and can be altered by lifestyle factors. We aimed to determine whether a 6-week training intervention altered fecal microbiome diversity and/or function in older males. Fecal samples were collected prior to and following a 6-week twice-weekly supervised resistance training intervention in 14 older Caucasian males (65 ± 10 years, 28.5 ± 3.2 kg/m2) with minimal prior training experience. Participants were randomized to receive a daily defatted peanut powder supplement providing 30 g protein (n = 8) or no supplement (n = 6) during the intervention. Bacterial DNA was isolated from pre-and post-training fecal samples, and taxa were identified using sequencing to amplify the variable region 4 (V4) of the 16S ribosomal RNA gene. Training significantly increased whole-body and lower-body lean mass (determined by dual energy X-ray absorptiometry) as well as leg extensor strength (p < 0.05) with no differences between intervention groups. Overall composition of the microbiome and a priori selected taxa were not significantly altered with training. However, MetaCYC pathway analysis indicated that metabolic capacity of the microbiome to produce mucin increased (p = 0.047); the tight junction protein, zonulin, was measured in serum and non-significantly decreased after training (p = 0.062). Our data suggest that resistance training may improve intestinal barrier integrity in older Caucasian males; further investigation is warranted.
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Affiliation(s)
- Johnathon H. Moore
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
| | - Kristen S. Smith
- Department of Nutrition, Dietetics and Hospitality Management, College of Human Sciences, Auburn University, Auburn, AL 36849, USA; (K.S.S.); (D.A.L.); (K.W.H.)
| | - Dongquan Chen
- Department of Cell, Developmental, and Integrative Biology, Division of Preventive Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (D.C.); (C.D.M.)
| | - Donald A. Lamb
- Department of Nutrition, Dietetics and Hospitality Management, College of Human Sciences, Auburn University, Auburn, AL 36849, USA; (K.S.S.); (D.A.L.); (K.W.H.)
| | - Morgan A. Smith
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
| | - Shelby C. Osburn
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
| | - Bradley A. Ruple
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
| | - Casey D. Morrow
- Department of Cell, Developmental, and Integrative Biology, Division of Preventive Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (D.C.); (C.D.M.)
| | - Kevin W. Huggins
- Department of Nutrition, Dietetics and Hospitality Management, College of Human Sciences, Auburn University, Auburn, AL 36849, USA; (K.S.S.); (D.A.L.); (K.W.H.)
| | - James R. McDonald
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
| | - Michael D. Brown
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
| | - Kaelin C. Young
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine-Auburn Campus, Auburn, AL 36832, USA
| | - Michael D. Roberts
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (J.H.M.); (M.A.S.); (S.C.O.); (B.A.R.); (J.R.M.); (M.D.B.); (K.C.Y.); (M.D.R.)
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine-Auburn Campus, Auburn, AL 36832, USA
| | - Andrew D. Frugé
- Department of Nutrition, Dietetics and Hospitality Management, College of Human Sciences, Auburn University, Auburn, AL 36849, USA; (K.S.S.); (D.A.L.); (K.W.H.)
- Correspondence:
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10
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Sexton CL, Smith MA, Smith KS, Osburn SC, Godwin JS, Ruple BA, Hendricks AM, Mobley CB, Goodlett MD, Frugé AD, Young KC, Roberts MD. Effects of Peanut Protein Supplementation on Resistance Training Adaptations in Younger Adults. Nutrients 2021; 13:nu13113981. [PMID: 34836236 PMCID: PMC8621247 DOI: 10.3390/nu13113981] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/29/2021] [Accepted: 11/05/2021] [Indexed: 12/11/2022] Open
Abstract
Protein supplementation is a commonly employed strategy to enhance resistance training adaptations. However, little research to date has examined if peanut protein supplementation is effective in this regard. Thus, we sought to determine if peanut protein supplementation (PP; 75 total g/d of powder providing 30 g/d protein, >9.2 g/d essential amino acids, ~315 kcal/d) affected resistance training adaptations in college-aged adults. Forty-seven college-aged adults (n = 34 females, n = 13 males) with minimal prior training experience were randomly assigned to a PP group (n = 18 females, n = 5 males) or a non-supplement group (CTL; n = 16 females, n = 8 males) (ClinicalTrials.gov trial registration NCT04707963; registered 13 January 2021). Body composition and strength variables were obtained prior to the intervention (PRE). Participants then completed 10 weeks of full-body resistance training (twice weekly) and PP participants consumed their supplement daily. POST measures were obtained 72 h following the last training bout and were identical to PRE testing measures. Muscle biopsies were also obtained at PRE, 24 h following the first exercise bout, and at POST. The first two biopsy time points were used to determine myofibrillar protein synthesis (MyoPS) rates in response to a naïve training bout with or without PP, and the PRE and POST biopsies were used to determine muscle fiber adaptations in females only. Dependent variables were analyzed in males and females separately using two-way (supplement × time) repeated measures ANOVAs, unless otherwise stated. The 24-h integrated MyoPS response to the first naïve training bout was similar between PP and CTL participants (dependent samples t-test p = 0.759 for females, p = 0.912 for males). For males, the only significant supplement × time interactions were for DXA-derived fat mass (interaction p = 0.034) and knee extensor peak torque (interaction p = 0.010); these variables significantly increased in the CTL group (p < 0.05), but not the PP group. For females, no significant supplement × time interactions existed, although interactions for whole body lean tissue mass (p = 0.088) and vastus lateralis thickness (p = 0.099) approached significance and magnitude increases in these characteristics favored the PP versus CTL group. In summary, this is the second study to determine the effects of PP supplementation on resistance training adaptations. While PP supplementation did not significantly enhance training adaptations, the aforementioned trends in females, the limited n-size in males, and this being the second PP supplementation study warrant more research to determine if different PP dosing strategies are more effective than the current approach.
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Affiliation(s)
- Casey L. Sexton
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
| | - Morgan A. Smith
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
| | - Kristen S. Smith
- Department of Nutrition, Dietetics and Hospitality Management, Auburn University, Auburn, AL 36849, USA; (K.S.S.); (A.D.F.)
| | - Shelby C. Osburn
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
| | - Joshua S. Godwin
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
| | - Bradley A. Ruple
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
| | - Alex M. Hendricks
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
| | - Christopher B. Mobley
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
| | - Michael D. Goodlett
- Athletics Department, Auburn University, Auburn, AL 36849, USA;
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine, Auburn, AL 36832, USA
| | - Andrew D. Frugé
- Department of Nutrition, Dietetics and Hospitality Management, Auburn University, Auburn, AL 36849, USA; (K.S.S.); (A.D.F.)
| | - Kaelin C. Young
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine, Auburn, AL 36832, USA
| | - Michael D. Roberts
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA; (C.L.S.); (M.A.S.); (S.C.O.); (J.S.G.); (B.A.R.); (A.M.H.); (C.B.M.); (K.C.Y.)
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine, Auburn, AL 36832, USA
- Correspondence: ; Tel.: +1-334-844-1925; Fax: +1-334-944-1467
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11
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Ruple BA, Godwin JS, Mesquita PHC, Osburn SC, Sexton CL, Smith MA, Ogletree JC, Goodlett MD, Edison JL, Ferrando AA, Fruge AD, Kavazis AN, Young KC, Roberts MD. Myofibril and Mitochondrial Area Changes in Type I and II Fibers Following 10 Weeks of Resistance Training in Previously Untrained Men. Front Physiol 2021; 12:728683. [PMID: 34630147 PMCID: PMC8497692 DOI: 10.3389/fphys.2021.728683] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/25/2021] [Indexed: 12/19/2022] Open
Abstract
Resistance training increases muscle fiber hypertrophy, but the morphological adaptations that occur within muscle fibers remain largely unresolved. Fifteen males with minimal training experience (24±4years, 23.9±3.1kg/m2 body mass index) performed 10weeks of conventional, full-body resistance training (2× weekly). Body composition, the radiological density of the vastus lateralis muscle using peripheral quantitative computed tomography (pQCT), and vastus lateralis muscle biopsies were obtained 1week prior to and 72h following the last training bout. Quantification of myofibril and mitochondrial areas in type I (positive for MyHC I) and II (positive for MyHC IIa/IIx) fibers was performed using immunohistochemistry (IHC) techniques. Relative myosin heavy chain and actin protein abundances per wet muscle weight as well as citrate synthase (CS) activity assays were also obtained on tissue lysates. Training increased whole-body lean mass, mid-thigh muscle cross-sectional area, mean and type II fiber cross-sectional areas (fCSA), and maximal strength values for leg press, bench press, and deadlift (p<0.05). The intracellular area occupied by myofibrils in type I or II fibers was not altered with training, suggesting a proportional expansion of myofibrils with fCSA increases. However, our histological analysis was unable to differentiate whether increases in myofibril number or girth occurred. Relative myosin heavy chain and actin protein abundances also did not change with training. IHC indicated training increased mitochondrial areas in both fiber types (p=0.018), albeit CS activity levels remained unaltered with training suggesting a discordance between these assays. Interestingly, although pQCT-derived muscle density increased with training (p=0.036), suggestive of myofibril packing, a positive association existed between training-induced changes in this metric and changes in mean fiber myofibril area (r=0.600, p=0.018). To summarize, our data imply that shorter-term resistance training promotes a proportional expansion of the area occupied by myofibrils and a disproportional expansion of the area occupied by mitochondria in type I and II fibers. Additionally, IHC and biochemical techniques should be viewed independently from one another given the lack of agreement between the variables assessed herein. Finally, the pQCT may be a viable tool to non-invasively track morphological changes (specifically myofibril density) in muscle tissue.
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Affiliation(s)
- Bradley A Ruple
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Joshua S Godwin
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Shelby C Osburn
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Casey L Sexton
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Morgan A Smith
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Michael D Goodlett
- Athletics Department, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
| | - Joseph L Edison
- Athletics Department, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
| | - Arny A Ferrando
- Department of Geriatrics, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AK, United States
| | - Andrew D Fruge
- Department of Nutrition, Dietetics and Hospitality Management, Auburn University, Auburn, AL, United States
| | | | - Kaelin C Young
- School of Kinesiology, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
| | - Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
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12
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Ruple BA, Godwin JS, Mesquita PHC, Osburn SC, Vann CG, Lamb DA, Sexton CL, Candow DG, Forbes SC, Frugé AD, Kavazis AN, Young KC, Seaborne RA, Sharples AP, Roberts MD. Resistance training rejuvenates the mitochondrial methylome in aged human skeletal muscle. FASEB J 2021; 35:e21864. [PMID: 34423880 DOI: 10.1096/fj.202100873rr] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 08/03/2021] [Accepted: 08/05/2021] [Indexed: 11/11/2022]
Abstract
Resistance training (RT) dynamically alters the skeletal muscle nuclear DNA methylome. However, no study has examined if RT affects the mitochondrial DNA (mtDNA) methylome. Herein, ten older, Caucasian untrained males (65 ± 7 y.o.) performed six weeks of full-body RT (twice weekly). Body composition and knee extensor torque were assessed prior to and 72 h following the last RT session. Vastus lateralis (VL) biopsies were also obtained. VL DNA was subjected to reduced representation bisulfite sequencing providing excellent coverage across the ~16-kilobase mtDNA methylome (254 CpG sites). Biochemical assays were also performed, and older male data were compared to younger trained males (22 ± 2 y.o., n = 7, n = 6 Caucasian & n = 1 African American). RT increased whole-body lean tissue mass (p = .017), VL thickness (p = .012), and knee extensor torque (p = .029) in older males. RT also affected the mtDNA methylome, as 63% (159/254) of the CpG sites demonstrated reduced methylation (p < .05). Several mtDNA sites presented a more "youthful" signature in older males after RT in comparison to younger males. The 1.12 kilobase mtDNA D-loop/control region, which regulates replication and transcription, possessed enriched hypomethylation in older males following RT. Enhanced expression of mitochondrial H- and L-strand genes and complex III/IV protein levels were also observed (p < .05). While limited to a shorter-term intervention, this is the first evidence showing that RT alters the mtDNA methylome in skeletal muscle. Observed methylome alterations may enhance mitochondrial transcription, and RT evokes mitochondrial methylome profiles to mimic younger men. The significance of these findings relative to broader RT-induced epigenetic changes needs to be elucidated.
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Affiliation(s)
- Bradley A Ruple
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | - Joshua S Godwin
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | | | - Shelby C Osburn
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | | | - Donald A Lamb
- Department of Nutrition, Dietetics and Hospitality Management, Auburn University, Auburn, Alabama, USA
| | - Casey L Sexton
- School of Kinesiology, Auburn University, Auburn, Alabama, USA
| | - Darren G Candow
- Faculty of Kinesiology and Health Studies, University of Regina, Regina, Saskatchewan, Canada
| | - Scott C Forbes
- Faculty of Education, Department of Physical Education Studies, Brandon University, Brandon, Manitoba, Canada
| | - Andrew D Frugé
- Department of Nutrition, Dietetics and Hospitality Management, Auburn University, Auburn, Alabama, USA
| | | | - Kaelin C Young
- School of Kinesiology, Auburn University, Auburn, Alabama, USA.,Edward Via College of Osteopathic Medicine, Auburn, Alabama, USA
| | - Robert A Seaborne
- Centre for Genomics and Child Health, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Adam P Sharples
- Institute for Physical Performance, Norwegian School of Sport Sciences, Olso, Norway
| | - Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, Alabama, USA.,Edward Via College of Osteopathic Medicine, Auburn, Alabama, USA
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13
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Plant Proteins and Exercise: What Role Can Plant Proteins Have in Promoting Adaptations to Exercise? Nutrients 2021; 13:nu13061962. [PMID: 34200501 PMCID: PMC8230006 DOI: 10.3390/nu13061962] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/02/2021] [Accepted: 06/05/2021] [Indexed: 01/10/2023] Open
Abstract
Adequate dietary protein is important for many aspects of health with current evidence suggesting that exercising individuals need greater amounts of protein. When assessing protein quality, animal sources of protein routinely rank amongst the highest in quality, largely due to the higher levels of essential amino acids they possess in addition to exhibiting more favorable levels of digestibility and absorption patterns of the amino acids. In recent years, the inclusion of plant protein sources in the diet has grown and evidence continues to accumulate on the comparison of various plant protein sources and animal protein sources in their ability to stimulate muscle protein synthesis (MPS), heighten exercise training adaptations, and facilitate recovery from exercise. Without question, the most robust changes in MPS come from efficacious doses of a whey protein isolate, but several studies have highlighted the successful ability of different plant sources to significantly elevate resting rates of MPS. In terms of facilitating prolonged adaptations to exercise training, multiple studies have indicated that a dose of plant protein that offers enough essential amino acids, especially leucine, consumed over 8–12 weeks can stimulate similar adaptations as seen with animal protein sources. More research is needed to see if longer supplementation periods maintain equivalence between the protein sources. Several practices exist whereby the anabolic potential of a plant protein source can be improved and generally, more research is needed to best understand which practice (if any) offers notable advantages. In conclusion, as one considers the favorable health implications of increasing plant intake as well as environmental sustainability, the interest in consuming more plant proteins will continue to be present. The evidence base for plant proteins in exercising individuals has seen impressive growth with many of these findings now indicating that consumption of a plant protein source in an efficacious dose (typically larger than an animal protein) can instigate similar and favorable changes in amino acid update, MPS rates, and exercise training adaptations such as strength and body composition as well as recovery.
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14
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Effects of Resistance Training on the Redox Status of Skeletal Muscle in Older Adults. Antioxidants (Basel) 2021; 10:antiox10030350. [PMID: 33652958 PMCID: PMC7996821 DOI: 10.3390/antiox10030350] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/19/2021] [Accepted: 02/21/2021] [Indexed: 12/23/2022] Open
Abstract
The aim of this study was to investigate the effects of resistance training (RT) on the redox status of skeletal muscle in older adults. Thirteen males aged 64 ± 9 years performed full-body RT 2x/week for 6 weeks. Muscle biopsies were obtained from the vastus lateralis prior to and following RT. The mRNA, protein, and enzymatic activity levels of various endogenous antioxidants were determined. In addition, skeletal muscle 4-hydroxynonenal and protein carbonyls were determined as markers of oxidative damage. Protein levels of heat shock proteins (HSPs) were also quantified. RT increased mRNA levels of all assayed antioxidant genes, albeit protein levels either did not change or decreased. RT increased total antioxidant capacity, catalase, and glutathione reductase activities, and decreased glutathione peroxidase activity. Lipid peroxidation also decreased and HSP60 protein increased following RT. In summary, 6 weeks of RT decreased oxidative damage and increased antioxidant enzyme activities. Our results suggest the older adult responses to RT involve multi-level (transcriptional, post-transcriptional, and post-translational) control of the redox status of skeletal muscle.
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