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ABSTRACT Introduction: Load reduction using the repetition maximum (RM) method may be necessary to promote higher numbers of repetitions, and consequently, higher total volume, time under tension, and perceived exertion ratings. Objective: To compare the effects of different leg press exercise loads on number of repetitions, total volume, time under tension, and perceived exertion. Methods: Eighteen women university students (23.9 ± 3.8 years) performed two experimental sessions with 90% and 100% of 10-12 RM in a balanced crossover design. Results: The number of repetitions of the second and third sets, the total volume, and time under tension at 90% of 10-12 RM was statistically higher than at 100% of 10-12 RM ( p < 0.05). The perceived exertion of the first and second sets and the training load (perceived exertion x duration of sessions) were higher at 100% of the 10-12 RM session ( p < 0.05). Conclusion: A small reduction in load results in a greater number of repetitions, total volume, and time under tension. The session with the higher load appeared to induce higher perceived exertion and training load. Thus, scientists and coaches might consider lower loads to maximize the number of repetitions, total volume, and time under tension, which may cause greater long-term muscular adaptations. Level of evidence II; Comparative prospective study.
RESUMEN Introducción: La reducción de la carga por el método de las repeticiones máximas (RM) puede ser necesaria para promover un mayor número de repeticiones y, consecuentemente, un mayor volumen total, tiempo bajo tensión y calificaciones del esfuerzo percibido. Objetivo: Comparar los efectos de diferentes cargas del ejercicio de prensa de piernas sobre el número de repeticiones, volumen, tiempo bajo tensión y esfuerzo percibido. Métodos: Dieciocho estudiantes universitarios (23,9 ± 3,8 años) realizaron dos sesiones experimentales con el 90% y el 100% de 10-12 RM en un diseño trasversal equilibrado. Resultados: El número de repeticiones de la segunda y tercera serie, el volumen total y el tiempo bajo tensión al 90% de 10-12 RM fue estadísticamente mayor que al 100% de 10-12 RM (p < 0,05). El esfuerzo percibido de la primera y segunda serie y la carga de entrenamiento (esfuerzo percibido x duración de las sesiones) fueron superiores en la sesión realizada al 100% de 10-12 RM (p < 0,05). Conclusión: Una pequeña reducción de la carga da lugar a un mayor número de repeticiones, volumen total y tiempo bajo tensión. La sesión con mayor carga indujo un mayor esfuerzo percibido y carga de entrenamiento. Por lo tanto, los científicos y entrenadores pueden considerar cargas más bajas para maximizar el número de repeticiones, el volumen total y el tiempo bajo tensión, lo que puede causar mayores adaptaciones musculares a largo plazo. Nivel de evidencia II; Estudio prospectivo comparativo.
RESUMO Introdução: A redução da carga pelo método das repetições máximas (RM) pode ser necessária para promover maior número de repetições e, consequentemente, maior volume total, tempo sob tensão e classificações do esforço percebido. Objetivo: Comparar os efeitos de diferentes cargas do exercício leg press no número de repetições, volume total, tempo sob tensão e percepção de esforço. Métodos: Dezoito universitárias (23,9 ± 3,8 anos) realizaram duas sessões experimentais com 90% e 100% de 10-12 RM em desenho transversal balanceado. Resultados: O número de repetições da segunda e terceira séries, volume total e tempo sob tensão a 90% de 10-12 RM foi estatisticamente maior do que a 100% de 10-12 RM (p < 0,05). A percepção do esforço da primeira e segunda séries e a carga de treinamento (percepção do esforço x duração das sessões) foram maiores na sessão realizada com 100% de 10-12 RM (p < 0,05). Conclusão: Uma pequena redução da carga resulta em maior número de repetições, volume total e tempo sob tensão. A sessão com maior carga induziu maior percepção do esforço e carga de treinamento. Assim, cientistas e treinadores podem considerar cargas menores para maximizar o número de repetições, o volume total e o tempo sob tensão, o que pode causar maiores adaptações musculares a longo prazo. Nível de evidência II; Estudo prospectivo comparativo.
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The purpose of this research was to investigate the degree of agreement between data from the International Physical Activity Questionnaire-Short Form (IPAQ) and accelerometer (ActiGraph®) readings for physical activity (PA), classified as moderate, vigorous, and moderate-vigorous PA, and sedentary behavior (SB) in participants with major depressive or bipolar disorder. Following a cross-sectional observational design (n = 30), participants used an accelerometer for 4 to 7 days (minimum of 10 h per day) and answered the IPAQ (for the same period as accelerometer use). Our results suggest significant differences (p < 0.05) when comparing the ActiGraph® and IPAQ data: for moderate PA, 155 min vs. 25 min per week; for moderate-vigorous PA, 157 min vs. 50 min per week; and for SB, 8 h vs. 3 h per day. Spearman's correlation coefficients (ActiGraph® and IPAQ) were low for moderate PA, vigorous PA, and moderate-vigorous PA (rho = 0.03 to 0.13). The Bland-Altman plot showed a bias of -75 min for moderate PA, 9 min for vigorous PA, -66 min for moderate-vigorous PA, and -5 h for SB. Considering the differences observed and the objectivity of the ActiGraph® measurements, whenever possible, we recommend ActiGraph® measurements of PA and SB for these clinical groups.
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Transtorno Bipolar , Transtorno Depressivo Maior , Humanos , Estudos Transversais , Inquéritos e Questionários , Exercício Físico/fisiologiaRESUMO
The aim of the study is to control the effect of myofascial mobilization on flexibility values ââin young men. 23 young adult men, aged between 18 and 30 years (74.8 ± 9.8 kg; 1.74 ± 0.06 cm; 24.7 ± 3.0 kg/m2), participated in the study, separated into experimental and control groups. Participants of the experimental group received an instrument assisted soft-tissue mobilization (IASTM) session, bilateral, in the muscular region of the quadriceps femoris, hamstrings and triceps surae. The rectus femoris, vastus lateralis and medial, biceps femoris, semitendinosus, semimembranosus, gastrocnemius and soleus muscles were mobilized for a period of 60 seconds. In the control session, participants remained at rest for a period of 15 minutes. The flexibility assessments were performed pre- and- immediately, 24 hours, and 48 hours post-sessions of both groups. The myofascial mobilization session promoted percentage increases in flexibility significantly higher at 24 hours when compared to values ââimmediately after, 24 hours and 48 hours after the control session (P < 0.05). The percentage increases in flexibility 48 hours after the myofascial mobilization session were significantly greater when compared to values ââimmediately post and 24 hours after the control session (P < 0.05). The findings of the present study suggest that an instrument assisted soft-tissue mobilization (IASTM) session promotes increases in flexibility in young adults one and two days after the intervention. (AU)
O objetivo do presente estudo foi verificar o efeito da mobilização miofascial nos valores da flexibilidade em homens jovens. Participaram do estudo 23 homens adultos jovens, com idade entre 18 e 30 anos (74,8 ± 9,8 kg; 1,74 ± 0,06 cm; 24,7 ± 3,0 kg/m2), separados em grupo experimental e controle. Os participantes do grupo experimental receberam uma sessão mobilização miofascial assistida por instrumento (IASTM), bilateralmente, na região muscular do quadríceps femural, isquiotibiais e tríceps sural. Os músculos reto femural, vasto lateral e medial, bíceps femoral, semitendinoso, semimembranoso, gastrocnêmio e sóleo foram mobilizados por um período de 60 segundos. Na sessão controle, os participantes permaneceram em repouso por um período de 15 minutos. As avaliações da flexiblidade foram realizadas pré, imediatamente após, 24 horas e 48 horas após as sessões de ambos os grupos. A sessão de mobilização miofascial promoveu aumentos percentuais da flexibilidade 24 horas significativamente maiores quando comparado aos valores imediatamente pós, 24 horas e 48 horas da sessão controle (P < 0,05). Os aumentos percentuais da flexibilidade 48 horas após a sessão mobilização miofascial foram significativamente maiores quando comparado aos valores imediatamente pós e 24 horas da sessão controle (P < 0,05). Os achados do presente estudo sugerem que uma sessão de mobilização miofascial assistida por instrumento promove aumentos da flexibilidade em adultos jovens após um e dois dias à intervenção.(AU)
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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.
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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 & dosagemRESUMO
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.
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Idoso Fragilizado , Força da Mão , Idoso , Humanos , Refeições , Pessoa de Meia-Idade , Força Muscular , Músculo Esquelético , Músculos , Equilíbrio Postural , Estudos de Tempo e MovimentoRESUMO
BACKGROUND: Frailty is a multifactorial geriatric syndrome characterized by progressive decline in health and associated with decreased muscle mass, strength, and functional capacity. Resistance training (RT) combined with protein or amino acids supplementation has been shown to be promising for mitigating age-related impairments. AIM: To investigate the chronic effects of different strategies of protein and derivatives supplementation in association with RT on selected health-related parameters in pre-frail and frail elderly. METHODS: This is a series of double-blind, randomized, placebo-controlled, parallel-group clinical trials. Volunteers will be divided into nine groups, comprising four different sub-studies evaluating the effects of: isolated leucine supplementation (study 1); protein source (whey vs. soy - study 2); combination of whey protein and creatine (study 3); and sexual dimorphism on the response to protein intake and RT (males vs. females - study 4). Muscle cross-sectional area, fiber cross-sectional area, body composition, lower-limb maximal dynamic and isometric strength, functionality, lipid profile, biochemical parameters, renal function, quality of life, and nutritional status will be assessed before and after a 16-week intervention period. Data will be tested for normality and a mixed-model for repeated measures will be conducted to assess within- and between-group effects of the intervention on the dependent variables. Confidence intervals (95%), effect sizes, and relative changes will also be determined, with significance set at p < 0.05.
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Envelhecimento , Proteínas Alimentares/uso terapêutico , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição do Idoso , Músculo Esquelético/fisiologia , Treinamento Resistido , Sarcopenia/prevenção & controle , Idoso , Terapia Combinada , Proteínas Alimentares/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Idoso Fragilizado , Fragilidade/etiologia , Fragilidade/prevenção & controle , Humanos , Leucina/efeitos adversos , Leucina/uso terapêutico , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Sarcopenia/diagnóstico por imagem , Sarcopenia/fisiopatologia , Sarcopenia/terapia , Índice de Gravidade de Doença , Caracteres Sexuais , Proteínas de Soja/efeitos adversos , Proteínas de Soja/uso terapêutico , Ultrassonografia , Proteínas do Soro do Leite/efeitos adversos , Proteínas do Soro do Leite/uso terapêuticoRESUMO
OBJECTIVE: This study investigated the chronic effects of different rest intervals (RIs) between sets on dynamic and isometric muscle strength and muscle activity. DESIGN: We used a repeated-measures design (pretraining and posttraining) with independent groups (different RI). Twenty-one resistance-trained older women (66.4 ± 4.4 years) were randomly assigned to either a 1-minute RI group (G-1 min; n = 10) or 3-minute RI group (G-3 min; n = 11). Both groups completed 3 supervised sessions per week during 8 weeks. In each session, participants performed 3 sets of 15 repetitions of leg press exercise, with a load that elicited muscle failure in the third set. Fifteen maximum repetitions, maximal voluntary contraction, peak rate of force development, and integrated electromyography activity of the vastus lateralis and vastus medialis muscles were assessed pretraining and posttraining. RESULTS: There was a significant increase in load of 15 maximum repetitions posttraining for G-3 min only (3.6%; P < 0.05). However, posttraining results showed no significant differences between G-1 min and G-3 min groups for all dependent variables (P > 0.05). CONCLUSIONS: The findings suggest that different RIs between sets did not influence dynamic and isometric muscle strength and muscle activity in resistance-trained older women.
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Contração Isométrica/fisiologia , Força Muscular/fisiologia , Treinamento Resistido/métodos , Descanso/fisiologia , Fatores de Tempo , Idoso , Eletromiografia , Feminino , Humanos , Pessoa de Meia-Idade , Músculo Quadríceps/fisiologiaRESUMO
Abstract The use of shorter rest intervals (RI) between sets of weight exercises has demonstrated to be a strategy to cause elevations of growth hormone concentrations (GH) in young adults. However, is not yet well established whether the magnitude of these elevations is influenced by the aging process. Thus, the aim of this study was to analyze the effect of different RI between sets of weight exercises on GH concentrations. Eighteen trained older women (65.8 ± 4.4 years; 70.2 ± 11.8 kg; 158.2 ± 5.1 cm) were submitted to two experimental exercise sessions in the leg press (separated by intervals between 48 and 72 hours). Both sessions consisted of three sets all performed with absolute loads of 15 maximal repetitions. Participants were instructed to perform maximum repetitions possible in each set until volitional muscle fatigue. In each experimental session, one of the different RI between sets was used: one minute (RI-1) or three minutes (RI-3). A randomized cross-over balanced design was used to determine the order of experimental sessions. Blood samples were collected to determine GH concentrations immediately before and after leg press exercise. Only the session performed with RI-1 showed significant elevations (50.7%; P < 0.05) in GH concentrations after exercise. However, significant differences in post-exercise GH concentrations were not observed between RI (P > 0.05). The results suggest that the use of different RI between sets does not influence the GH concentrations in trained older women.
Resumo A utilização de menores intervalos de recuperação (IR) entre as séries de exercícios com pesos têm-se demonstrado uma estratégia para ocasionar elevações nas concentrações do GH em adultos jovens. No entanto, ainda não está bem estabelecido se a magnitude destas elevações é influenciada pelo processo de envelhecimento. Assim, o objetivo do presente estudo foi analisar o efeito de diferentes IR entre as séries de um exercício com pesos nas concentrações do hormônio do crescimento (GH). Dezoito idosas treinadas (65,8± 4,4 anos; 70,2± 11,8 kg; 158,2± 5,1 cm) foram submetidas a duas sessões experimentais no exercício leg-press, separadas por intervalos entre 48 e 72 horas. Ambas as sessões consistiram de três séries, todas executadas com as cargas absolutas de 15 repetições máximas. As participantes foram instruídas para realizarem o máximo de repetições possíveis em cada série, até a fadiga muscular voluntária. Em cada sessão experimental foi empregado um dos diferentes IR entre as séries: um minuto (IR-1) ou três minutos (IR-3). Um delineamento cross-over balanceado foi utilizado para determinar a ordem das sessões. As coletas sanguíneas para determinar as concentrações do GH foram realizadas imediatamente pré e pós-exercício leg-press. Somente a sessão realizada com IR-1 apresentou elevações significativas (50,7%; P < 0,05) nas concentrações do GH pós-exercício. Entretanto, diferenças significativas nas concentrações do GH pós-exercício não foram observadas entre os dois IR (P > 0,05). Os resultados sugerem que a utilização de diferentes IR entre as séries não influencia nas concentrações do GH pós-exercício, em idosas treinadas.
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Estudos têm indicado o efeito da velocidade de movimento (VM) na promoção do desempenho e hipertrofia muscular de adultos jovens e idosos, contudo, não se sabe qual a velocidade mais adequada para tais melhorias. O objetivo desta revisão é verificar o efeito crônico de diferentes VM na hipertrofia e desempenho muscular, em jovens e idosos. Para tanto, foi realizada uma busca sistemática nas bases de dados: Biological Abstracts, LILACS®, MEDLINE® (Pubmed), SciELO®, Scopus e Oxford Journal. Foram incluídos nesta revisão 12 artigos originais que avaliaram força máxima isométrica e dinâmica (contração voluntária máxima, uma repetição máxima, potência) e hipertrofia muscular em humanos maiores de 18 anos após períodos de TP com diferentes VM. Foram identificados 12 estudos. Os resultados sugerem que para jovens, a maior parte dos estudos demonstra aumento similar da potência, força e hipertrofia muscular independentemente VM treinada. Para idosos, a maioria dos estudos confirma melhora da força muscular independentemente VM treinada. Contudo, para a potência ainda há controvérsias, pois alguns suportam que VM rápida e lenta são eficientes igualmente, enquanto outros afirmam que VM rápida é melhor. Apenas um estudo com idosos avaliou a hipertrofia e este encontrou que ambas VM são eficientes para aumento da mesma. Assim, conclui-se que independente da faixa etária, para força muscular, ambas as velocidades são recomendadas e eficazes. Entretanto, para hipertrofia e potência muscular ainda há controvérsias na literatura, necessitando que se desenvolvam mais estudos que busquem esclarecer tais imprecisões.
Studies have shown the effect of moving speed (MV) promoting muscle hypertrophy and performance of young and elderly adults, however, it is unclear what the most suitable speed for such improvements. The aim of this review is to evaluate the effect of different MV chronic hypertrophy and muscle performance in young and elderly. Therefore, we performed a systematic search in databases: Biological Abstracts, LILACS ®, MEDLINE ® (PubMed), SciELO ®, Scopus and Oxford Journal. Included in this review were 12 original articles that assessed maximal isometric and dynamic strength (maximal voluntary contraction, one repetition maximum power) and muscle hypertrophy in humans 18 years after periods of strength training with different MV. We identified 12 studies. The results suggest that for young people, most of the studies show a similar increase in power, strength, and muscle hypertrophy independently of MV trained. For seniors, the majority of studies confirms improves muscle strength regardless MV trained. However, in the power is still controversial because some of which supports fast and slow MV are also effective, while others claim MV faster is better. Only one study evaluated the elderly hypertrophy and found that both MV are effective for increase. Thus, it is concluded that regardless of age for muscular strength, both speeds are recommended and effective. However, for hypertrophy and muscular power is still controversial in the literature, requiring them to develop more studies that seek to clarify such inaccuracies.
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Movimento , Força Muscular , TutoriaRESUMO
INTRODUÇÃO: O treinamento com pesos (TP) tem sido amplamente empregado em adultos idosos com objetivo de minimizar ou reverter os efeitos deletérios do processo de envelhecimento no sistema neuromuscular. No entanto, os potenciais benefícios do TP para a pressão arterial e frequência cardíaca de repouso de adultos idosos ainda permanecem controversos. OBJETIVO: Analisar o efeito de oito semanas de TP na pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), pressão arterial média (PAM) e frequência cardíaca (FC) de repouso em idosas sem hipertensão arterial. MÉTODOS: Dezessete mulheres idosas (66,0 ± 5,8 anos) sem experiência em TP foram separadas aleatoriamente em grupo treinamento (GT; n = 10) e grupo controle (GC; n = 7). As variáveis hemodinâmicas de repouso foram avaliadas pelo método auscultatório (esfigmomanômetro de mercúrio) e frequencímetro cardíaco (Polar), antes e após oito semanas do período experimental. RESULTADOS: Reduções atribuíveis ao TP foram encontradas apenas para a PAS (-13,4 mmHg; p < 0,01). Apesar de reduções significativas terem sido observadas para a PAD e PAM, a análise de covariância não mostrou interação Grupo x Momento significativa. CONCLUSÃO: O TP se mostrou um treinamento eficaz para promover adaptações no sistema cardiovascular de mulheres idosas sem hipertensão arterial. Oito semanas de TP pode reduzir significativamente a PAS de repouso de mulheres idosas.
INTRODUCTION: Resistance training (RT) has been widely used for older adults in order to minimize or reverse the deleterious effects of aging in the neuromuscular system. However, the potential benefits of RT on arterial blood pressure and heart rate at rest in older adults remain controversial. OBJECTIVE: To analyze the effect of eight weeks of RT on systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) in older women without hypertension. METHODS: Seventeen women (aged 66.0 ± 5.8 years) without previous experience in RT were randomly assigned to either a training (TG, n = 10) or control (CG, n = 7) groups. Hemodynamic parameters at rest were evaluated by auscultatory method (mercury sphygmomanometer) and HR monitor (Polar), before and after eight weeks of experimental period. RESULTS: Reductions attributable to RT were found only to SBP (-13.4 mmHg, p <0.01). Although significant reductions were observed for DBP and MBP, the analysis of covariance showed no interaction Group x Time significant. CONCLUSION: RT proved an effective training to promote adaptations in the cardiovascular system of older women without hypertension. Eight weeks of RT can significantly reduce SBP at rest in older women.