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1.
Nutrients ; 15(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36986095

RESUMO

The aim of this study was to compare the potential additional effect of chia flour, whey protein, and a placebo juice to resistance training on fat-free mass (FFM) and strength gains in untrained young men. Eighteen healthy, untrained young men underwent an 8-week whole-body resistance training program, comprising three sessions per week. Subjects were randomized into three groups that after each training session consumed: (1) 30 g whey protein concentrate containing 23 g protein (WG), (2) 50 g chia flour containing 20 g protein (CG), or (3) a placebo not containing protein (PG). Strength tests (lower- and upper-limb one repetition maximum (1 RM) tests) and body composition analyses (dual-energy X-ray absorptiometry; DXA) were performed before (PRE) and after (POST) the intervention. Resistance training increased FFM and the 1 RM for each of the strength tests similarly in the three groups. FFM increased by 2.3% in WG (p = 0.04), by 3.6% in CG (p = 0.004), and by 3.0% in PG (p = 0.002)., and 1 RM increased in the different strength tests in the three groups (p < 0.05) with no difference between PG, CG, and WG. In conclusion, neither chia flour nor whey protein supplementation elicited an enhanced effect on FFM and strength gains after an 8-week resistance training program in healthy, untrained young men consuming a habitual high protein mixed diet (>1.2 g/kg/day).


Assuntos
Farinha , Treinamento Resistido , Masculino , Humanos , Proteínas do Soro do Leite , Suplementos Nutricionais , Método Duplo-Cego , Composição Corporal , Força Muscular , Músculo Esquelético
2.
Clin Nutr ; 40(8): 4849-4858, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34358827

RESUMO

BACKGROUND: Sarcopenia plays a central role in the development of frailty syndrome. Nutrition and exercise are cornerstone strategies to mitigate the transition to frailty; however, there is a paucity of evidence for which dietary and exercise strategies are effective. OBJECTIVE: This large, multifactorial trial investigated the efficacy of different dietary strategies to enhance the adaptations to resistance training in pre-frail and frail elderly. METHODS: This was a single-site 16-week, double-blind, randomized, placebo-controlled trial conducted at the Clinical Hospital, School of Medicine - University of São Paulo, Sao Paulo, Brazil. Four integrated, sub-investigations were conducted to compare: 1) leucine vs. placebo; 2) whey vs. soy vs. placebo; 3) creatine vs. whey vs. creatine plus whey vs. placebo; 4) women vs. men in response to whey. Sub-investigations 1 to 3 were conducted in women, only. Two-hundred participants (154 women/46 men, mean age 72 ± 6 years) underwent a twice-a-week, resistance training program. The main outcomes were muscle function (assessed by dynamic and isometric strength and functional tests) and lean mass (assessed by DXA). Muscle cross-sectional area, health-related quality of life, bone and fat mass, and biochemical markers were also assessed. RESULTS: We observed that leucine supplementation was ineffective to improve muscle mass and function. Supplementation with whey and soy failed to enhance resistance-training effects. Similarly, supplementation with neither whey nor creatine potentiated the adaptations to resistance training. Finally, no sex-based differences were found in response to whey supplementation. Resistance exercise per se increased muscle mass and function in all sub-investigations. There were no adverse effects. CONCLUSION: Neither protein (whey and soy), leucine, nor creatine supplementation enhanced resistance training-induced adaptations in pre-frail and frail elderly, regardless of sex. These findings do not support the notion that some widely used supplement-based interventions can add to the already potent effects of resistance exercise to counteract frailty-related muscle wasting and dynapenia. CLINICAL TRIAL REGISTRY: NCT01890382; https://clinicaltrials.gov/ct2/show/NCT01890382. DATA SHARING: Data described in the manuscript will be made available upon request pending application.


Assuntos
Suplementos Nutricionais , Idoso Fragilizado , Fragilidade/prevenção & controle , Treinamento Resistido/métodos , Sarcopenia/terapia , Adaptação Fisiológica/efeitos dos fármacos , Idoso , Brasil , Creatina/administração & dosagem , Método Duplo-Cego , Feminino , Fragilidade/etiologia , Humanos , Leucina/administração & dosagem , Masculino , Músculo Esquelético/efeitos dos fármacos , Qualidade de Vida , Sarcopenia/complicações , Fatores Sexuais , Proteínas de Soja/administração & dosagem , Proteínas do Soro do Leite/administração & dosagem
3.
Sports Med ; 51(6): 1317-1330, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33599941

RESUMO

BACKGROUND: Acute protein turnover studies suggest lower anabolic response after ingestion of plant vs. animal proteins. However, the effects of an exclusively plant-based protein diet on resistance training-induced adaptations are under investigation. OBJECTIVE: To investigate the effects of dietary protein source [exclusively plant-based vs. mixed diet] on changes in muscle mass and strength in healthy young men undertaking resistance training. METHODS: Nineteen young men who were habitual vegans (VEG 26 ± 5 years; 72.7 ± 7.1 kg, 22.9 ± 2.3 kg/m2) and nineteen young men who were omnivores (OMN 26 ± 4 years; 73.3 ± 7.8 kg, 23.6 ± 2.3 kg/m2) undertook a 12-week, twice weekly, supervised resistance training program. Habitual protein intake was assessed at baseline and adjusted to 1.6 g kg-1 day-1 via supplemental protein (soy for VEG or whey for OMN). Dietary intake was monitored every four weeks during the intervention. Leg lean mass, whole muscle, and muscle fiber cross-sectional area (CSA), as well as leg-press 1RM were assessed before (PRE) and after the intervention (POST). RESULTS: Both groups showed significant (all p < 0.05) PRE-to-POST increases in leg lean mass (VEG: 1.2 ± 1.0 kg; OMN: 1.2 ± 0.8 kg), rectus femoris CSA (VEG: 1.0 ± 0.6 cm2; OMN: 0.9 ± 0.5 cm2), vastus lateralis CSA (VEG: 2.2 ± 1.1 cm2; OMN: 2.8 ± 1.0 cm2), vastus lateralis muscle fiber type I (VEG: 741 ± 323 µm2; OMN: 677 ± 617 µm2) and type II CSA (VEG: 921 ± 458 µm2; OMN: 844 ± 638 µm2), and leg-press 1RM (VEG: 97 ± 38 kg; OMN: 117 ± 35 kg), with no between-group differences for any of the variables (all p > 0.05). CONCLUSION: A high-protein (~ 1.6 g kg-1 day-1), exclusively plant-based diet (plant-based whole foods + soy protein isolate supplementation) is not different than a protein-matched mixed diet (mixed whole foods + whey protein supplementation) in supporting muscle strength and mass accrual, suggesting that protein source does not affect resistance training-induced adaptations in untrained young men consuming adequate amounts of protein. CLINICAL TRIAL REGISTRATION: NCT03907059. April 8, 2019. Retrospectively registered.


Assuntos
Treinamento Resistido , Animais , Dieta , Dieta Vegetariana , Suplementos Nutricionais , Humanos , Masculino , Força Muscular , Músculo Esquelético , Veganos
4.
Eur J Clin Nutr ; 74(7): 1047-1053, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32265572

RESUMO

BACKGROUND: Aging is accompanied by the inability to optimally respond to anabolic stimulus of nutrition, with consequent loss of muscle mass and functionality. It has been speculated that not only total protein intake, but also the per meal protein dose may have important implications to protein balance and, hence, muscle mass in middle-aged and older adults, but evidence is lacking in a more vulnerable population such as the frail elderly. The aim was to investigate possible associations between total protein intake and its per meal dose with multiple measures of muscle mass, strength, and functionality in a cohort of pre-frail and frail elderly individuals. METHODS: One-hundred-and-fifty-seven pre-frail and frail elderly individuals were assessed for total and per meal protein intake (food diaries), total and appendicular lean mass (DXA), vastus lateralis cross-sectional area [(CSA) B-mode ultrasound], and muscle function [leg-press and bench press 1-RM, timed-stands test, timed-up-and-go test, handgrip, and risk of falls (Biodex Balance System®)]. RESULTS: Protein intake and number of meals with either ≥20 g or ≥30 g of protein were significantly associated (after controlling for confounding factors) with greater total and appendicular lean mass and vastus lateralis CSA. CONCLUSIONS: We found that not only total protein intake but also the number of high-protein containing meals are associated with muscle mass in frail and pre-frail elderly.


Assuntos
Idoso Fragilizado , Força da Mão , Idoso , Humanos , Refeições , Pessoa de Meia-Idade , Força Muscular , Músculo Esquelético , Músculos , Equilíbrio Postural , Estudos de Tempo e Movimento
5.
Med Sci Sports Exerc ; 52(8): 1809-1814, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32079916

RESUMO

INTRODUCTION: Several acute studies have suggested that leucine is a key amino acid to drive muscle protein synthesis. However, there are very few studies on the long-term effects of leucine supplementation on resistance training (RT)-induced gains in muscle mass and strength. We sought to determine the impact of 10 g of leucine on muscle mass and strength in response to RT in healthy young men. METHODS: Twenty-five, resistance-trained men (27 ± 5 yr; 78.4 ± 11.6 kg; 24.8 ± 3.0 kg·m) consuming 1.8 ± 0.4 g protein·kg·d, were randomly assigned to receive 2 × 5 g·d supplementation of either free leucine (LEU n = 12) or alanine (PLA n = 13) while undergoing a supervised 12-wk, twice-weekly lower-limb RT program. One-repetition maximum (leg-press 1RM) and muscle cross-sectional area (mCSA) of the vastus lateralis were determined before (PRE) and after (POST) the intervention. Additionally, three 24-h dietary recalls were also performed at PRE and POST. RESULTS: Protein intake was roughly double that of the RDA in both groups and remained unchanged across time with no differences detected between groups. Similar increases were observed between groups in leg-press 1RM (LEU, 19.0% ± 9.4% and PLA, 21.0% ± 10.4%, P = 0.31) and mCSA (LEU, 8.0% ± 5.6% and PLA, 8.4% ± 5.1%, P = 0.77). CONCLUSIONS: High-dose leucine supplementation did not enhance gains in muscle strength and mass after a 12-wk RT program in young resistance-trained males consuming adequate amounts of dietary protein.


Assuntos
Adaptação Fisiológica , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Leucina/administração & dosagem , Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido , Adulto , Método Duplo-Cego , Humanos , Extremidade Inferior/fisiologia , Masculino , Proteínas Musculares/biossíntese , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Treinamento Resistido/métodos , Ultrassonografia , Adulto Jovem
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