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The objective of the present study is to analyze the changes in bioimpedance vector analysis (BIVA) and phase angle (PhA) in sarcopenic older people submitted to a 12-week resistance training (RT) program according to classic and specific analyses. To this end, 20 sarcopenic older adults of both sexes, invited through media, underwent bioimpedance analysis before and after the RT carried out three times a week, for 12 weeks. The mean impedance vectors of the groups established for the confidence ellipses (95% of the confidence ellipse) are compared using Hotelling's T2 test. The distance D from Mahalanobis is also calculated. Classic and Specific BIVA are presented. The resistance values for the classical analyses (R/H) decreased across all groups (whole group, women and men, p < 0.05), with approximate decreases ranging from 9.4% to 10%, while the classic reactance (Xc/H) decreased (p < 0.05) only for the whole group (5.9%) and men (7.7%). For the specific BIVA, trends are verified for the whole sample, with a decrease in resistance (R.sp) and an increase in reactance (Xc.sp). In conclusion, the RT program in sarcopenic individuals promoted a reduction in resistance values in classical analyses, indicating a possible increase in hydration status and, consequently, musculoskeletal mass.
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OBJECTIVE: To investigate the effects of combining a Pilates program with photobiomodulation therapy (PBMT) in patients with chronic nonspecific low back pain (CNLBP). METHODS: Thirty-eight adults with CNLBP were randomly assigned to two groups: Pilates exercise + active PBMT (PIL + PBMT) or Pilates exercise + sham PBMT (PIL + SHAM). Both groups performed an 8-week mat Pilates program and received PBMT on their lumbar muscles 10 min before and after each session. The following variables were assessed before and after intervention: peak pain intensity, postural balance (i.e., center of the pressure [A-COP], velocity anteroposterior [Vel AP], and velocity mediolateral [Vel ML]), perceived disability (i.e., Oswestry Disability Index [ODI] and Roland Morris Disability Questionnaire [RMDQ]), and pain-related fear of movement (i.e., Tampa Scale of Kinesiophobia [TSK], Fear Avoidance Beliefs Questionnaire [FABQ], and Pain Catastrophizing Scale [PCS]). RESULTS: Postural balance variables showed no statistically significant differences (p > 0.05) across time or between groups. The groups showed similar (p < 0.05) reductions in peak pain intensity, ODI, RMDQ, and PCS scores, but no statistically significant difference (p > 0.05) in TSK and FABQ scores. CONCLUSION: The mat Pilates program reduced peak pain intensity, perceived disability, and pain catastrophizing in adults with CNLBP, but PBMT had no additional effect on these variables. Mat Pilates alone or combined with PBMT was not able to improve postural balance.
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Photobiomodulation therapy (PBMT) has been advocated as a potential intervention to improve muscle performance and recovery in the health and sports context. However, the short- and long-term effects of PBMT on endurance running performance remain under-researched and controversial. The purpose of this study was to investigate the acute dose-response effect of PBMT with light-emitting diodes (LEDs) on endurance performance and rating of perceived exertion (RPE; 6-20 Borg) during a 5-km running trial in recreational runners. In a crossover design, eighteen young adult runners (28.7 ± 7.8 years) were randomized to receive 1 of 4 PBMT conditions (placebo, 300, 900, and 1260 Joules [J]) 60 min before the 5-km running trial on four occasions, separated by a 2-wk washout period. The treatments were applied to the quadriceps, hamstrings, and gastrocnemius muscles of both legs using a device containing 200 LEDs (100 red and 100 infrared). The following variables were assessed: endurance performance (i.e. total time, mean velocity, and velocity in the split distances at the initial 200 m and every 400 m lap) and RPE in the split distances at the initial 200 m and every 400 m lap. Data normality and homogeneity were tested using Shapiro-Wilk's and Levene's tests, respectively. Differences between treatment conditions were assessed using the analysis of variance tests (one- or two-way ANOVA, depending on the comparisons), complemented by the Bonferroni post hoc test. There were significant time effects for the running velocity and RPE in the split distances (p < 0.0001), with no significant treatment-by-time interaction (running velocity, p = 0.59; RPE, p = 0.95). The mean velocity (p = 0.997), total time (p = 0.998), and total mean of the RPE (p = 0.91) were similar between treatment conditions. In conclusion, acute PBMT with LEDs at doses of 300, 900, and 1260 J is not recommended for improving endurance performance and RPE in the 5-km running trial in recreational runners.
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Estudios Cruzados , Terapia por Luz de Baja Intensidad , Carrera , Humanos , Terapia por Luz de Baja Intensidad/métodos , Terapia por Luz de Baja Intensidad/instrumentación , Carrera/fisiología , Adulto , Masculino , Método Doble Ciego , Adulto Joven , Femenino , Resistencia Física/efectos de la radiación , Músculo Esquelético/efectos de la radiación , Músculo Esquelético/fisiología , Rendimiento Atlético/fisiologíaRESUMEN
OBJECTIVE: This study was designed to analyze the association between the risk of undernutrition and indicators of hospital rehabilitation in patients with COVID-19 while controlling for confounding variables. METHODS: This was an analytical study conducted by analyzing the medical records of patients with COVID-19. A total of 562 adult patients were eligible for the study. In addition to the risk of undernutrition (independent variable), indicators of hospital rehabilitation (dependent variables) were evaluated. These indicators included the length of hospital stay, clinical outcome (discharge or death), food intake, mobility (bedridden status), the use of mechanical ventilation, and the need for enteral nutrition. Pre-existing comorbidities (confounding/control variables) were grouped into cardiovascular, metabolic/endocrine, neurological, chronic obstructive pulmonary disease, and other categories (neoplasms, multiple sclerosis, and kidney disease). A dichotomization model was applied for data analysis. The Chi-Square test was used to verify the association between the risk of undernutrition and the dependent variables. Associations with a significance level of P < 0.05 were subjected to Poisson regression to identify the prevalence ratio. RESULTS: Patients at risk of undernutrition had a 90% higher chance of being bedridden and were 35 times more likely to experience a decrease in food intake. They also had an 89% higher chance of using invasive mechanical ventilation and a 91% higher chance of requiring enteral nutrition. Additionally, individuals at risk of undernutrition had a 73% higher chance of death. Adjustment for comorbidities did not alter these associations, demonstrating that the risk of undernutrition is independently associated with indicators of hospital rehabilitation. CONCLUSION: The risk of undernutrition is independently associated with worsened indicators of hospital rehabilitation in patients with COVID-19, including higher prevalence of mortality.
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COVID-19 , Desnutrición , Adulto , Humanos , COVID-19/epidemiología , Desnutrición/epidemiología , Tiempo de Internación , Alta del Paciente , Hospitales , Estado Nutricional , Evaluación NutricionalRESUMEN
Abstract Aim: to compare the impact of different resistance exercise orders on postexercise hemodynamic measures in resistance-trained nonhypertensive middle-aged and older women. Methods: Twenty-three women (age 50-78 yrs) were randomized into two resistance training (RT) groups: one group started training sessions performing multi-joint exercises followed by single-joint exercises (MS, n = 12; 58.92 ± 5.53 yrs), while the other group performed their sessions in the opposite order (SM, n = 11; 57.93 ± 11.89 yrs). Both groups performed their RT sessions composed of 7 exercises performed in 3 sets of 10-15 repetitions maximum. Blood pressure was measured by automated equipment during pre-training and at 10, 20, 30, 40, 50, and 60 min after the training session. Results: Repeated-measures analysis of variance (ANOVA) identified an isolated effect of time only for systolic blood pressure (p = 0.003) with statistically significant reductions in pre-session measurement at 60 min post-session in both groups (MS: 117.67 ± 15.89 mmHg vs. 111.25 ± 11.84 mmHg and SM: 118.64 ± 15.13 mmHg vs. 111.50 ± 15.62 mmHg). Regarding diastolic blood pressure and subjective perception of effort, no difference was identified between groups (p > 0.05). Conclusion: We conclude that a RT session can promote post-exercise hypotension for systolic blood pressure after 60 min of recovery in middle-aged and nonhypertensive older women regardless of the exercise order.
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The induced adaptations from resistance training are dependent on the adequate manipulation of the variables involved in training, and volume is one of the most important. However, high volume training can be more stressful, thus prior information of the training volume to be performed may affect performance. The aim of this study is to verify the influence of prior knowledge of the number of sets to be performed on the training volume. For this, ten women (44 ± 2 years, 66 ± 9 kg, 165 ± 3 cm, 24 ± 2 kg / m2) with previous experience in resistance training (≥ 6 months) performed six sets in 45º leg press exercise in three conditions,: in the first (C1) the participants were informed that they would perform six sets and they completed them. In the second condition (C2), they were told they would perform three sets, however, after executing the third set, they were told to complete three more sets. In the third (C3), they did not receive information about how many sets they would complete, but they also did six sets. All sets were performed until the momentary concentric failure at 70% of the one repetition maximum. It was noted that there was no statistically significant difference among the conditions for the total number of repetitions (C1 = 119 ± 44; C2 = 123 ± 47; C3 = 121 ± 47; P = 0.98). Therefore, the results suggest that prior information on the number of sets to be performed in the session does not affect the volume of repetitions performed by middle-aged women. (AU)
As adaptações induzidas pelo treinamento resistido são dependentes da adequada manipulação das variáveis envolvidas no treinamento, sendo o volume uma das de maior destaque. Porém, um treinamento com alto volume pode ser mais desgastante, logo, a informação prévia do volume de treino a ser realizado poderá afetar o desempenho. O objetivo deste estudo foi verificar a influência do conhecimento prévio do número de séries a serem executadas sobre o volume de treino. Para isso, 10 mulheres (44 ± 2 anos, 66 ± 9 kg, 165 ± 3 cm, 24 ± 2 kg/m2 ) com experiência prévia em treinamento resistido (≥ 6 meses) realizaram seis séries no exercício leg press 45º em três condições distintas, a saber: na primeira condição (C1) as participantes foram informadas que realizariam seis séries e as completaram. Na segunda condição (C2), foram comunicadas que fariam três séries, porém, após executar a terceira série, elas foram orientadas a completar mais três séries. Já na terceira condição (C3), não receberam informação sobre quantas séries cumpririam, mas também fizeram seis séries. Todas as séries foram realizadas até a falha momentânea concêntrica a 70% da força máxima, determinada mediante teste de uma repetição máxima. Notou-se que não houve diferença estatisticamente significante entre as condições para a quantidade total de repetições (C1 = 119 ± 44; C2 = 123 ± 47; C3 = 121 ± 47; P = 0,98). Portanto, os resultados sugerem que a informação prévia da quantidade de séries a serem executadas na sessão não afeta o volume de repetições praticadas por mulheres de meia idade. (AU)
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OBJECTIVE: This study aims to investigate the effects of laser photobiomodulation (PBM) at 808 nm on biceps brachii performance to exhaustion, rating of perceived exertion (RPE), and delayed onset muscle soreness (DOMS) in untrained young women. METHODS: Thirteen young women (20.1 ± 2.9 years) participated in a crossover study in which they received, in a counterbalanced manner, active and placebo laser PBM on two occasions (T1 and T2), separated by a 7-day washout period. During T1 and T2, participants received active (100 mW output power, irradiance of 35.7 W cm-2, and total energy of 28 J/arm) or placebo laser irradiation on the biceps brachii muscle at 20 min before the repetitions-to-failure test [six sets at 60% of one-repetition maximum (1RM) until failure] for elbow flexion exercise. The number of repetitions performed and RPE over the six sets, as well as DOMS from basal up to 72 h after the repetitions-to-failure test, were recorded. RESULTS: There was a significant (time, p < 0.05) reduction in the number of repetitions performed and an increase in RPE over six sets, with no statistical differences between placebo and active laser conditions (treatment × time, p > 0.05). DOMS increased at 24 h postexercise and progressively returned to baseline after 72 h in both conditions (time, p < 0.05; treatment × time, p > 0.05). CONCLUSION: Our results indicate that acute laser PBM at 808 nm does not improve biceps brachii performance to exhaustion, RPE, and DOMS in untrained women.
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Specialized resistance training techniques (e.g., drop-set, rest-pause) are commonly used by well-trained subjects for maximizing muscle hypertrophy. Most of these techniques were designed to allow a greater training volume (i.e., total repetitions×load), due to the supposition that it elicits greater muscle mass gains. However, many studies that compared the traditional resistance training configuration with specialized techniques seek to equalize the volume between groups, making it difficult to determine the inherent hypertrophic potential of these advanced strategies, as well as, this equalization restricts part of the practical extrapolation on these findings. In this scenario, the objectives of this manuscript were 1) to present the nuance of the evidence that deals with the effectiveness of these specialized resistance training techniques and - primarily - to 2) propose possible ways to explore the hypertrophic potential of such strategies with greater ecological validity without losing the methodological rigor of controlling possible intervening variables; and thus, contributing to increasing the applicability of the findings and improving the effectiveness of hypertrophy-oriented resistance training programs.
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Músculo Esquelético/anatomía & histología , Entrenamiento de Fuerza/métodos , Humanos , Músculo Esquelético/crecimiento & desarrollo , Tamaño de los Órganos/fisiologíaRESUMEN
Abstract Manipulation of resistance training variables has been shown to have a substantial effect on muscular adaptations. A major variable in this process is exercise selection. In addition to the effectiveness of a given exercise to recruit the target muscle groups, safety considerations and individual comfort during execution of a lift should be considered. The correct biomechanics of the chosen exercise will assist in promoting desired muscle adaptations, while proper safety procedures will reduce risk of injury. Lifting comfort will facilitate enjoyment and foster adherence to the program. Therefore, the purpose of this paper was to offer guidelines for selection of resistance training exercises based on the Efficiency, Safety, and Comfort Analysis Method (ESCAM).
Resumo A manipulação das variáveis do treinamento resistido demonstraram ter um efeito substancial nas adaptações musculares. Uma variável importante neste processo é a seleção de exercícios. Além da eficácia de um determinado exercício para recrutar os grupos musculares-alvo, as considerações de segurança e conforto individual durante a execução de um levantamento devem ser considerados. A biomecânica correta do exercício escolhido ajudará a promover as adaptações musculares desejadas, enquanto os procedimentos de segurança adequados reduzirão o risco de lesões. O conforto no levantamento facilitará o prazer e promoverá a adesão ao programa. Portanto, o objetivo deste artigo é oferecer orientações para a seleção de exercícios no treinamento resistido com base no Método de Análise de Eficiência, Segurança e Conforto (ESCAM).
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The purpose of the study was to verify the effect of two dispositions of resistance exercises on rate of perceived of effort (RPE), discomfort and affectivity in older women. Twenty older women (68.0±6.6 years, 69.8±12.7 kg, and 155.9±7.0 cm) performed in a balanced and randomized design two experimental conditions, namely: a circuit (CIRC) fashion and another in a traditional (TRAD) fashion. In both conditions, six resistance exercises in the following order were performed: push press with kettlebell, swing with kettlebell, plantar flexion, squatting, ladder displacement and shoulder flexion with naval rope, with the same load and three sets of 15 repetitions/exercise. In the CIRC condition, the exercises were performed in stations, with no interval among them, and at the end of the last exercise, a three-minute interval was performed. For the TRAD condition the exercises were performed in consecutive sets, with intervals of 90s between the sets and the exercises. After 15 min of the closure of each session, the RPE (OMNI), feeling (Hardy and Rejeski) and a discomfort scale were applied. There was no significant difference (P>0.05) among the sessions for PSE (TRAD = 6.0±1.2 vs. CIRC = 6.1±0.9), feeling (TRAD = 3.7±1.6 vs. CIRC = 3.6±1.2) and discomfort (TRAD = 5.2±1.4 vs. CIRC = 5.1±1.3). The results suggest that PSE, discomfort and affective response to resistance exercises are similar when performed in CIRC or TRAD in older women. (AU)
O objetivo do estudo foi verificar o efeito de duas diferentes disposições de execução de exercícios resistidos sobre a percepção subjetiva de esforço (PSE), o desconforto e a afetividade em mulheres idosas. Vinte mulheres idosas (68,0±6,6 anos, 69,8±12,7 kg e 155,9±7,0 cm) foram distribuídas de forma balanceada e aleatorizada para duas condições experimentais: disposição de circuito (CIRC) e disposição tradicional (TRAD). Em ambas as condições, seis exercícios resistidos foram executados na seguinte ordem: push press com kettlebell, swing com kettlebell, flexão plantar, agachamento, deslocamento em escada e flexão de ombros com corda naval, com mesma carga e três séries de 15 repetições/exercício. Na condição CIRC os exercícios foram executados em forma de estações, sem intervalo entre os exercícios e, ao final de cada série foi concedido intervalo de três minutos. Para condição TRAD os exercícios foram executados em séries consecutivas, com intervalos de 90s entre os exercícios e as séries. Após 15 min do termino de cada sessão foram aplicadas as escalas de PSE (OMNI), sentimento (Hardy e Rejeski) e desconforto. Não ocorreram diferenças significativas (P>0,05) entre as sessões para PSE (TRAD = 6,0±1,2 vs CIRC = 6,1±0,9), sentimento (TRAD = 3,7±1,6 vs CIRC = 3,6±1,2) e desconforto (TRAD = 5,2±1,4 vs CIRC = 5,1±1,3). Os resultados sugerem que a PSE, o desconforto e a resposta afetiva aos exercícios resistidos são semelhantes quando realizados em CIRC ou TRAD em mulheres idosas. (AU)
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Resistance exercise has been widely recommended for elderly population, since this type of exercise induces important health benefits, especially to improve functional capacity and preserve muscle mass, thus reflecting on the quality of life of older individuals. Among the several components of the resistance exercises the selection of movements to be performed is one of the most important and must be carefully analyzed. Although there may be a wide range of options, the most important recommendations do not specifically indicate the movements that should be included and muscle groups that should be prioritized when prescribing resistance exercise for the elderly. Therefore, considering that there is a lack of information for the Physical Education professional about the topic, this study was developed to support the choices of the movements that will compose the resistance exercise program for the elderly. The study was carried out by compiling and analyzing assumptions and scientific evidences related to resistance exercises and needs of elderly individuals. In conclusion, the choice of movements should be based on the principles of kinesiology, the needs of the elderly, muscle action and exercise safety in order to obtain beneficial results for general health and attenuate possible risks. (AU)
O exercício resistido vem sendo amplamente recomendado para população idosa, uma vez que esse tipo de exercício físico induz a importantes benefícios para saúde; sobretudo, no aprimoramento da capacidade funcional e na preservação da massa muscular, refletindo, desse modo, na qualidade de vida do indivíduo idoso. Dentre os diversos componentes dos exercícios resistidos, a seleção dos movimentos a serem executados é um dos mais importantes e deve ser cuidadosamente analisado. Embora possa existir vasta gama de opções, as principais recomendações não indicam especificamente os movimentos que devem ser incluídos e os grupos musculares que devem ser priorizados nos programas de exercícios resistidos. Portanto, considerando haver uma lacuna de informações sobre o tema, o estudo foi realizado com intuito de subsidiar a seleção dos movimentos que deverão compor os programas de exercícios resistidos para idosos. O estudo foi realizado mediante compilação e análise de pressupostos e evidências científicas referentes aos exercícios resistidos e as necessidades dos idosos. Concluiu-se que a seleção dos movimentos deve ser baseada nos princípios da cinesiologia, nas necessidades dos idosos, na ação muscular e na segurança de execução para se alcançar resultados benéficos para saúde em geral e atenuar possíveis riscos. (AU)
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The purpose of this study was to investigate the effects of BCAA supplementation on muscle recovery from resistance exercise (RE) in untrained young adults. Twenty-four young adults (24.0 ± 4.3 years old) were assigned to 1 of 2 groups (n = 12 per group): a placebo-supplement group or a BCAA-supplement group. The groups were supplemented for a period of 5 days. On day 1 and 3, both groups underwent a RE session involving two lower body exercises (hack squat and leg press) and then were evaluated for muscle recovery on the 3 subsequent moments after the RE session [30 min (day 3), 24 h (day 4), and 48 h (day 5)]. The following indicators of muscle recovery were assessed: number of repetitions, rating of perceived exertion in the last RE session, muscle soreness and countermovement jump (CMJ) during recovery period (30 min, 24 h, and 48 h after RE session). Number of repetitions remained unchanged over time (time, P > 0.05), while the rating of perceived exertion increased (time, P < 0.05) over 3 sets, with no difference between groups (group × time, P > 0.05). Muscle soreness increased (time, P < 0.05) and jumping weight decreased (time, P < 0.05) at 30 min post-exercise and then progressively returned to baseline at 24 and 48 h post-exercise, with no difference between groups (group × time, P > 0.05). The results indicate that BCAA supplementation does not improve muscle recovery from RE in untrained young adults.
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Aminoácidos de Cadena Ramificada/administración & dosificación , Músculo Esquelético/fisiología , Entrenamiento de Fuerza , Adulto , Aminoácidos de Cadena Ramificada/metabolismo , Suplementos Dietéticos , Método Doble Ciego , Ejercicio Físico/fisiología , Humanos , Contracción Muscular/fisiología , Mialgia , Factores de Tiempo , Adulto JovenRESUMEN
The aim of this study was to compare the effects of linear periodization (LP) versus nonperiodized (NP) resistance training on upper-body isometric force and skeletal muscle mass (SMM) in sarcopenic older adults. Twenty sarcopenic older adults were randomly assigned into the LP and NP groups and performed 16 weeks of resistance training. The SMM was measured by octopolar bioelectrical impedance. The isometric force for handgrip and trunk were assessed by dynamometer. Evaluations were performed at baseline, after 4, 8, 12, and 16 weeks of resistance training. For total weight lifted, there was a main effect for time (F=126.986, P<0.001), statistically significant difference between condition (F=13.867, P=0.001) and interaction (F=8.778, P<0.001), whereby total weight lifted was greater for NP after 4 months of training. Isometric force for handgrip and trunk increased across time (P<0.001) but no significant differences between groups or interaction were observed (P>0.05). The SMM increased across time (P<0.05), however no significant difference between groups or interaction were observed (P>0.05). There were strong and significant correlations between handgrip maximum force and SMM (LP: rho=0.79, P=0.004 vs. NP: rho=-0.43, P=0.244) and handgrip mean force and SMM (LP: rho=0.68, P=0.021 vs. NP: rho=-0.37, P=0.332) only for the LP group. In conclusion, LP and NP resistance training induced similar benefits on upper-body isometric force and SMM in sarcopenic older adults. However, LP presented lower total weight lifted, suggesting that it is possible to obtain similar gains in isometric force and SMM with less total work.
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ß-Alanine supplementation has been shown to increase muscle carnosine levels and exercise performance. However, its effects on muscle recovery from resistance exercise (RE) remains unknown. The purpose of this study was to investigate the effects of ß-alanine supplementation on muscle function during recovery from a single session of high-intensity RE. Twenty-four untrained young adults (22.1 ± 4.6 years old) were assigned to one of two groups (N = 12 per group): a placebo-supplement group (4.8 g/day) or an ß-alanine-supplement group (4.8 g/day). The groups completed a single session of high-intensity RE after 28 days of supplementation and were then evaluated for muscle function on the three subsequent days (at 24, 48, and 72 h postexercise) to assess the time course of muscle recovery. The following indicators of muscle recovery were assessed: number of repetitions until failure, rating of perceived exertion, muscle soreness, and blood levels of creatine kinase (CK). Number of repetitions until failure increased from 24 to 48 h and 72 h of recovery (time P < 0.01), with no difference between groups. There was a significant increase in the rating of perceived exertion among the sets during the RE session (time P < 0.01), with no difference between the groups. No difference was observed over time and between groups in rating of perceived exertion in the functional tests during recovery period. Blood CK levels and muscle soreness increased at 24 h postexercise and then progressively declined at 48 and 72 h postexercise, respectively (time P < 0.05), with no difference between groups. In conclusion, our data indicate that ß-alanine supplementation does not improve muscle recovery following a high-intensity RE session in untrained young adults.
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Suplementos Dietéticos , Ejercicio Físico , Músculo Esquelético/fisiología , Mialgia/fisiopatología , Entrenamiento de Fuerza , beta-Alanina/administración & dosificación , Adulto , Método Doble Ciego , Humanos , Masculino , Músculo Esquelético/efectos de los fármacos , Recuperación de la Función , Adulto JovenRESUMEN
OBJECTIVE: To analyse the effect of resistance training (RT) frequency on muscle mass, appendicular lean soft tissue, insulin-like growth factor 1 (IGF-1), testosterone, and their changes with detraining in older women. METHODS: Forty-five physically independent older women (≥ 60â years) were randomly assigned to perform RT either two (G2X, n = 21) or three times/week (G3X, n = 24), during 12â weeks (8 exercises, 1 set of 10-15 repetition maximum). Muscle mass and appendicular lean soft tissue, IGF-1, testosterone, and dietary intake were measured at pre-training, post-training, and after detraining (12â weeks). RESULTS: Muscle mass and appendicular lean soft tissue significantly increased post-training (G2X = +5.5% and G3X = +5.8%, P < .0001) with no differences between groups, and gains were retained after detraining (G2X = 100% and G3X = 99%, P < .0001). IGF-1 and dietary intake did not change for the groups during the study. Testosterone did not change post-training but significantly decreased after detraining (G2X = -21% and G3X = -50%, P < .0001). CONCLUSION: We conclude that lower RT frequency is as effective as higher frequency to improve muscle mass and appendicular lean soft tissue, and to maintain testosterone and IGF-1. Additionally, detraining may reduce testosterone regardless of RT frequency. These results are specifically for community-dwelling older women and may not be generalized to other populations.
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Composición Corporal , Factor I del Crecimiento Similar a la Insulina/análisis , Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Testosterona/sangre , Anciano , Femenino , Humanos , Persona de Mediana EdadRESUMEN
The purpose of the present study was to analyze the effects of the order of resistance training (RT) exercises on hypertrophy in young adult men. Thirty-six young adult men (age, 21.9 ± 2.5 years; body mass, 72.6 ± 12.1 kg, height, 176.9 ± 7.4 cm; body mass index, 23.1 ± 3.3 kg/m2) were randomly assigned to 1 of 2 training groups that performed a 6-week RT program in either (i) a traditional approach starting with multi-joint (MJ) exercises followed by single-joint exercises (SJ) (MJ-SJ, n = 19) or (ii) in reverse order (SJ-MJ, n = 17). Muscle thickness of the biceps brachii and mid-thigh were assessed by ultrasound. Lean soft tissue (LST) was assessed by dual-energy X-ray absorptiometry. Both groups similarly increased (P < 0.05) biceps brachii thickness (MJ-SJ = +14.2%, SJ-MJ = +13.8%). Alternatively, only the MJ-SJ group presented an increase in mid-thigh thickness from pre- to post-training (MJ-SJ = +7.2%, SJ-MJ = +3.9%). Upper limb LSTs (MJ-SJ = +5.2%, SJ-MJ = +7.5%) were statistically similar between conditions, and a trend for significance (P = 0.07) was found for trunk LST (MJ-SJ = +7.2%, SJ-MJ = +1.7%). Nonsignificant pre- to post-training changes were observed for lower limb LSTs (MJ-SJ = +0.7%, SJ-MJ = +1.8%). Our data suggest that both sequences are effective for increasing muscle hypertrophy over a short-term RT period; there may be a potentially beneficial hypertrophic effect for the mid-thigh by performing exercises in a manner that progresses from MJ to SJ exercises.
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Contracción Muscular , Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Absorciometría de Fotón , Adaptación Fisiológica , Factores de Edad , Humanos , Hipertrofia , Masculino , Músculo Esquelético/diagnóstico por imagen , Factores Sexuales , Ultrasonografía , Adulto JovenRESUMEN
Abstract Overweight among older adults has increased considerably, and resistance training (RT) is a very attractive intervention strategy for positive changes associated with its practice. The aim was to evaluate the impact of nutritional status on body composition and muscle strength of older women in a RT program. Forty-eight older women were divided into three groups: eutrophic (EUT, BMI ≤ 24.9 kg/m2), overweight (OVE, BMI between 25.0 and 29.9 kg/m2) and obese (OBE, BMI ≥ 30.0 kg/m2). RT was performed for 12 weeks, one set of 10 to 15 repetitions, eight exercises, three weekly sessions. Body composition assessments (muscle mass, fat mass and trunk fat), strength and muscle quality were performed. Interaction for muscle mass in EUT had significant effect (+ 4.0%) when compared to OVE (+ 1.4%) and OBE (+ 1.4%). Time effect was observed for muscle strength (EUT = + 10.6%, OVE = + 7.5% and OBE = + 11.0%), muscle quality (EUT = + 6.1%, OVE = + 6.3% and OBE = + 9.8%), trunk fat (EUT = - 3.3%, OVE = - 0.7% and OBE = - 0.7%) and fat mass (EUT = - 3.0%, OVE = - 1.5% and OBE = - 0.5%). The results suggest that RT is effective for improving strength, muscle quality, muscle mass, trunk fat and fat mass of older women, but nutritional status may be determinant in muscle mass changes.
Resumo O objetivo do presente estudo foi avaliar o impacto do estado nutricional na composição corporal e força muscular de idosas inseridas em um programa de treinamento com pesos (TP). Quarenta e oito idosas foram divididas em três grupos: eutróficas (EUT, IMC ? 24,9 kg/m²), sobrepeso (SOB, IMC entre 25,0 e 29,9 kg/m²) e obesas (OBE, IMC ? 30,0 kg/m2). O TP foi realizado por 12 semanas, uma série de 10 a 15 repetições, oito exercícios, três sessões semanais. Avaliações da composição corporal (massa muscular, massa gorda e gordura de tronco), força e qualidade muscular foi realizado. Interação foi encontrada para a massa muscular onde o grupo EUT apresentaram efeito significativo (+ 4,0%) quando comparado ao SOB (+ 1,4%) e OBE (+ 1,4%). Efeito do tempo foi observado para a força muscular (EUT = + 10,6%, SOB = + 7,5% e OBE = + 11,0%), qualidade muscular (EUT = + 6,1%, SOB = + 6,3% e OBE = + 9,8%), gordura de tronco (EUT = - 3,3%, SOB = - 0,7% e OBE = - 0,7%) e massa gorda (EUT = - 3,0%, SOB = - 1,5% e OBE = - 0,5%). Os resultados sugerem que o TP é efetivo para a melhora da força, qualidade muscular, massa muscular, gordura de tronco e massa gorda de mulheres idosas, porém o estado nutricional pode ser determinante nas modificações da massa muscular.
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Humanos , Femenino , Salud del Anciano , Entrenamiento de Fuerza , Composición Corporal , Conducta AlimentariaRESUMEN
The purpose of this study was to examine the effects of free leucine supplementation on changes in skeletal muscle mass and strength during a resistance training (RT) program in previously untrained, young subjects. In a double-blind, randomized, placebo-controlled study, 20 healthy young (22 ± 2 years) participants were assigned to two groups: a placebo-supplement group (PLA, N = 10) or a leucine-supplement group (LEU, N = 10). Both groups underwent an 8-week hypertrophic RT program (2 days/week), consuming an equivalent amount of leucine (3.0 g/day in a single post-training dose) or placebo (cornstarch). Quadriceps muscle strength, cross-sectional area (CSA) of the vastus lateralis (VL), and rectus femoris (RF), as well as the habitual dietary intake were assessed before and after the 8-week intervention period. There was a similar improvement in muscle strength (Leg press, LEU: +33% vs. PLA: +37%; P > 0.05, and knee extension, LEU: +31% vs. PLA: 34%; P > 0.05) and CSA (VL, LEU: 8.9% vs. PLA: 9.6%; P > 0.05, and RF, LEU: +21.6% vs. PLA: + 16.4%; P > 0.05) in the both groups from pre- to post-training. In addition, there was no significant (P > 0.05) difference in daily dietary intake between the LEU and PLA groups before and after the intervention period. Free leucine supplementation (3.0 g/day post-training) does not increase muscle strength or CSA during RT in healthy young subjects consuming adequate dietary protein intake.
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Suplementos Dietéticos , Leucina/administración & dosificación , Músculo Esquelético/fisiología , Resistencia Física/efectos de los fármacos , Aptitud Física/fisiología , Adolescente , Adulto , Estudios Transversales , Método Doble Ciego , Femenino , Humanos , Masculino , Factores de TiempoRESUMEN
This study compared maturation, body composition and physical fitness between youth soccer athletes with different technical skills levels. Sixty-two young athletes (11-17 years) were categorized dichotomously in more skilled (n=31) and less skilled (n=31) groups based on 3 specific technical tests (Dribbling Speed Test [DST], Shuttle Dribble Test [SDT] and Slalom Dribble Test [SLDT]). Chronological and skeletal age, time of practice, body composition and 4 physical fitness tests were performed for comparisons. As expected, the 3 technical tests were correlated (r=0.47-0.54, P<0.05). More skilled subjects in DST and SDT showed (respectively) higher time of practice (effect size [ES]=0.72 and 0.90), and greater performance sit-ups (ES=1.23 and 0.81), squat jump (ES=1.10 and 1.08), countermovement jump (ES=1.11 and 1.10), and Yo-Yo test (ES=1.17 and 1.40) compared to the less skilled subjects (P<0.05). However, more skilled subjects in SLDT showed greater performance (P<0.05) only in the squat jump (ES=0.67) and Yo-Yo tests (ES=0.83). The results suggest that technical performance is associated with greater time of practice and some physical capabilities. Moreover, the DST and SDT tests seem to be good options to discriminate technical performance in youth soccer athletes.
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Antropometría , Rendimiento Atlético/fisiología , Destreza Motora/fisiología , Acondicionamiento Físico Humano , Aptitud Física , Maduración Sexual/fisiología , Fútbol/fisiología , Adolescente , Factores de Edad , Composición Corporal , Niño , Prueba de Esfuerzo , Humanos , Masculino , Factores de TiempoRESUMEN
This study analyzed the effects of 12 weeks of resistance training (RT) on resting blood pressure (BP) and plasma levels of nitric oxide metabolites (NOx) in pre- and hypertensive older women, and evaluated the relationship between these 2 parameters. Thirty-five older women (68.2±5.7 years, 70.0±14.4 kg, 157.1±6.4 cm, 28.3±5.0 kg.m-2) were randomly allocated into a training group (TG; n=17), which performed a 12-week RT program, and a control group (CG; n=18), which did not perform any physical exercise. Anthropometry, one repetition maximum (1RM), body composition analysis by dual energy X-ray absorptiometry, blood samples, and resting BP were measured. There was a significant interaction for all variables analyzed, in which reductions of systolic BP (-8.5%), diastolic BP (-8.4%), and mean arterial pressure (-8.5%), and increases of NOx (+35.2%) were observed only for the TG. Moreover, a negative and significant correlation was observed (P<0.05; r=-0.63) between NOx and systolic BP in the TG. Results suggest that a 12-week RT program is sufficient to induce reductions in BP in pre- and hypertensive older women and that the decrease in systolic BP is associated with an increase in plasma NOx concentration.