A razão entre a concentração de testosterona e cortisol (T:C) é freqüentemente utilizada como indicativo do nível de estresse imposto pelo exercício. Alterações na concentração destes hormônios são responsáveis por modular diversas respostas induzidas pelo treinamento, como hipertrofia e ganho de força. O objetivo do presente estudo foi examinar a influência do protocolo de treinamento de força, conhecido como múltiplas-séries (MS), sobre o ganho de força, de resistência muscular localizada e a relação entre a concentração de hormônios catabólicos (cortisol) e anabólicos (testosterona). Para testar esta hipótese cinco jovens do sexo feminino com um ano de experiência em treinamento de força foram submetidas ao protocolo MS. As amostras de sangue foram coletadas antes e imediatamente após o exercício, no primeiro dia e após oito semanas de treinamento. Os testes de 1-RM e de repetições máximas foram realizados também no início e ao final das oito semanas de treinamento de força. Não foram observadas alterações na massa corporal, no IMC, na percentagem de massa gorda e na força máxima (1-RM) no supino, no agachamento e na rosca direta. O número de repetições máximas a 50% de 1-RM foi aumentado apenas para o supino (p < 0,05). Não foi observada alteração na concentração de testosterona total. Com relação à concentração plasmática de cortisol, após oito semanas de treino, na situação de repouso, foi reduzida (38% - p < 0,05). Em conseqüência da atenuação da secreção de cortisol após oito semanas de treinamento, a razão T:C apresentou elevação de 20% na situação de repouso (p < 0,05). Apesar de não terem sido detectadas alterações funcionais nos testes de 1-RM e repetições máximas, o método MS induziu um quadro hormonal favorável ao anabolismo protéico.
The present study investigated the associations between frailty status and (a) daily protein intake, (b) daily body weight-adjusted protein intake, (c) branched-chain amino acid (BCAA) consumption, (d) evenness of protein distribution across main meals, (e) number of daily meals providing at least 30 g of protein, and (f) number of daily meals providing at least 0.4 g protein/kg of body weight in community-dwelling older adults. The relationship between frailty status and protein-related dietary parameters was explored across different frailty assessment tools. Two hundred older adults were enrolled in the study. Participant frailty status was determined according to a modified Fried’s frailty phenotype (mFP), the FRAIL scale, and the Study of Osteoporotic Fracture (SOF) index. Diet was assessed by 24-h dietary recall, while diet composition was estimated using a nutritional software. A frailty instrument-dependent relationship was observed between frailty status and protein-related dietary parameters. Protein consumption was associated with frailty status only in participants identified as frail according to the mFP. In addition, protein and BCAA intake was found to be greater in robust and pre-frail participants relative to their frail counterparts. Our findings suggest that the association between frailty and protein-related dietary parameters is tool dependent. Specifically, protein and BCAA consumption appears to be lower only in older adults identified as frail by the mFP.
The present study compared the effects of traditional resistance training (TRT) and combined power training (PT) and TRT (PTRT) on cognitive parameters and serum brain-derived neurotrophic factor (BDNF) levels in non-demented, well-functioning, community-dwelling older women. Forty-five older women were randomized into one of three experimental groups: TRT, PTRT, and control group (CG). Cognitive tests explored global cognitive function, short-term memory, and dual-task performance. Serum BDNF levels were assessed at baseline and after the intervention. Exercise sessions were performed twice a week over 22 weeks. In TRT, exercise sessions were based on three sets of 8–10 repetitions at “difficult” intensity. In PTRT, the first session was based on PT (three sets of 8−10 repetitions at “moderate” intensity), while the second session was similar to the TRT. Our analyses indicated that overall cognitive function, short-term memory, and dual-task performance were similarly improved after TRT and PTRT. Serum BDNF concentrations were not altered by any training protocol. In conclusion, the two RT programs tested in the present trial improved global cognitive function, short-term memory and dual task performance in non-demented, well-functioning, community-dwelling older women. In addition, our findings suggest that mechanisms other than BDNF may be associated with such improvements.
Estudos disponíveis na literatura demonstram que a realização prévia de um exercício de endurance afeta de modo adverso o desempenho no exercício de força subseqüente. Tal ocorrência pode estar relacionada a mudanças metabólicas induzidas pelo exercício de endurance. O objetivo deste trabalho foi verificar se a ingestão de carboidrato (CHO) pode atenuar os efeitos de uma sessão aguda de exercício de endurance sobre o desempenho de força. A fim de testar essa hipótese, seis estudantes universitárias (164 ± 5,9cm; 64,9 ± 7,2kg), com experiência em treinamento de força, foram submetidas a um teste para a determinação do VO2pico (44 ± 4,3ml.min-1) e um teste de 1-RM para o leg press (186 ± 22,5kg) seguido de um teste de repetições máximas (duas séries de leg press realizado a 70% de 1-RM até exaustão 1ª série 21 ± 2,6 e 2ª série 11 ± 1,9 repetições) em dias diferentes. Seguindo um protocolo duplo-cego, os sujeitos foram submetidos a duas condições experimentais, recebendo uma bebida placebo (P) ou outra contendo carboidrato (6% - maltodextrina), antes (500ml) e durante (500ml) a realização de uma sessão de exercício de endurance (corrida em esteira 70% do VO2pico por 45 minutos). Em seguida ao exercício de endurance, os indivíduos realizaram um teste de 1-RM seguido pelo teste de repetições máximas. Não foram observadas mudanças no teste de 1-RM e na concentração plasmática de glicose entre as condições experimentais (P x CHO). O número de repetições máximas a 70%-1RM apresentou decréscimo nas duas situações (P 1ª série 13 ± 2,9 repetições e 2ª série 6 ± 2,1 repetições; CHO 1ª série 15 ± 2,5 repetições e 2ª série 7 ± 1,7 repetições, p < 0,05), não havendo diferença entre ambas. Uma sessão de exercício de endurance (intensidade moderada e longa duração) realizada previamente afeta de modo negativo a capacidade de realizar repetições máximas. Independente do mecanismo envolvido na redução do número de repetições máximas, o consumo de carboidrato foi incapaz de reverter esse efeito prejudicial.
The purpose of this study was to assess the influence of two different resistance training protocols on the anthropometric (weight, BMI, fat mass), functional parameters (1-MR test, and maximal repetition test) and the parameters related to the endocrine system (testosterone and cortisol concentrations), as well as to the immunological system (glutamine and IgC concentrations). The study was composed by twelve trained men (27.4 ± 4.8 years), who were randomly divided in two groups that later were submitted to two different training protocols: the Multiple Series (MS), and Tri-set (TS). Blood samplings were collected before and after an resistance training session in the beginning and the end of the 8 weeks training period. It was observed no alterations in the morphofunctional parameters (except as to the maximal repetition test for the squat). As to the endocrine parameters, it was observed that the TS caused a significant increase in the cortisol immediately after the training session both in the beginning and in the end of the eight weeks (p < 0.05) period. Upon the observation of the testosterone vs. cortisol ratio (T:C) behavior, it can be observed a noticeable increase in the group submitted to the MS protocol after the 8 weeks training period (p < 0.05). As to the immunological parameters, it was observed no alterations in the concentration of the immunoglobulin G. The concentration of the glutamine suffered a decrease after 8 weeks in both groups. That decrease had a higher accentuation in the TS group (p < 0.05). Results attained suggest that the TS method imposed a higher stress to the body. Furthermore, these data also indicate that the MS protocol promotes a more propitious environment to the anabolism after the 8 weeks training period. However, both methods did not succeed in promoting significant changes in the morphofunctional parameters.
Aim: The current study investigated the effects of low-speed resistance training (LSRT) and high-speed resistance training (HSRT) on frailty status, physical performance, cognitive function and blood pressure in pre-frail and frail older people.Material and Methods: Sixty older adults, 32 prefrail and 28 frail, were randomly allocated into LSRT, HSRT, and control group (CG). Before and after intervention periods frailty status, blood pressure, heart rate, and a set of physical performance capabilities and cognitive domains were assessed. Exercise interventions occurred over 16 weeks and included four resistance exercises with 4–8 sets of 4–10 repetitions at moderate intensity.Results: The prevalence of frailty criteria in prefrail and frail older adults were reduced after both LSRT and HSRT. In prefrail, LSRT significantly improved lower-limb muscle strength, while mobility was only improved after HSRT. Muscle power and dual-task performance were significantly increased in both LSRT and HSRT. In frail, LSRT and HSRT similarly improved lower-limb muscle strength and power. However, exclusive improvements in dual-task were observed after LSRT. Memory was significantly increased in prefrail and frail, regardless of the type of resistance training. No significant changes were observed in blood pressure and heart rate.Conclusion: Findings of the present study indicated that both LSRT and HSRT reversed frailty status and improved physical performance in prefrail and frail older adults. Notably, different patterns of improvement were observed among RT protocols. Regarding frailty status, LSRT seemed to be more effective in reverse prefrailty and frailty when compared to HSRT. Greater improvements in muscle strength and power were also observed after LSRT, while HSRT produced superior increases in mobility and dual-task performance. One-leg stand performance was significantly reduced in LSRT, but not HSRT and CG, after 16 weeks. In contrast, RT programs similarly improved verbal memory in prefrail. Finally, no changes in blood pressure and heart rate were observed, regardless of the type of RT.Trial Registration: The protocol was approved by the University of Campinas Human Research Ethics Committee (Protocol No. 20021919.7.0000.5404) and retrospectively registered at ClinicalTrials.gov Protocol Registration and Results System: NCT04868071.
The present study investigated and compared the patterns of dietary protein intake and physical function in Brazilian and Italian older women. Seventy-five Brazilian older women were recruited in a community senior center. Fifty-three age-matched Italian older women were selected from participants of the Longevity check-up (Lookup) 7+ study. In both samples, physical performance was evaluated by isometric handgrip strength (IHG) and five-time sit-to-stand (5 × STS) tests, while diet was assessed through 24-h recall. Results indicated that Brazilian women had a higher intake of plant-based protein (52.7% vs. 30.5% kcal), while Italian women consumed greater amounts of animal-derived protein (29.7% vs. 41.5% kcal). In Brazilian women, the binary logistic regression analysis indicated that body weight-adjusted protein consumption was associated with IHG adjusted by body mass index and with 5 × STS performance. In the Italian sample, the intake of isoleucine, leucine, and valine was significantly associated with 5 × STS performance. Our findings indicate that Brazilian and Italian community-dwelling older women show different patterns of protein intake, with higher consumption of plant-based protein in the Brazilian sample and higher ingestion of animal-derived protein in the Italian subgroup. These dietary patterns may differentially impact the relationship between physical function and protein intake observed in Brazilian and Italian older women.
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