The metabolic stress induced by blood flow restriction (BFR) during resistance training (RT) might maximize muscle growth. However, it is currently unknown whether metabolic stress are associated with muscle hypertrophy after RT protocols with high- or low load. Therefore, the aim of the study was to compare the effect of high load RT (HL-RT), high load BFR (HL-BFR), and low load BFR (LL-BFR) on deoxyhemoglobin concentration [HHb] (proxy marker of metabolic stress), muscle cross-sectional area (CSA), activation, strength, architecture and edema before (T1), after 5 (T2), and 10 weeks (T3) of training with these protocols. Additionally, we analyzed the occurrence of association between muscle deoxygenation and muscle hypertrophy. Thirty young men were selected and each of participants’ legs was allocated to one of the three experimental protocols in a randomized and balanced way according to quartiles of the baseline CSA and leg extension 1-RM values of the dominant leg. The dynamic maximum strength was measured by 1-RM test and vastus lateralis (VL) muscle cross-sectional area CSA echo intensity (CSA echo ) and pennation angle (PA) were performed through ultrasound images. The measurement of muscle activation by surface electromyography (EMG) and [HHb] through near-infrared spectroscopy (NIRS) of VL were performed during the training session with relative load obtained after the 1-RM, before (T1), after 5 (T2), and 10 weeks (T3) training. The training total volume (TTV) was greater for HL-RT and HL-BFR compared to LL-BFR. There was no difference in 1-RM, CSA, CSA echo, CSA echo /CSA, and PA increases between protocols. Regarding the magnitude of the EMG, the HL-RT and HL-BFR groups showed higher values than and LL-BFR. On the other hand, [HHb] was higher for HL-BFR and LL-BFR. In conclusion, our results suggest that the addition of BFR to exercise contributes to neuromuscular adaptations only when RT is performed with low-load. Furthermore, we found a significant association between the changes in [HHb] (i.e., metabolic stress) and increases in muscle CSA from T2 to T3 only for the LL-BFR, when muscle edema was attenuated.

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The aim of the present study was to investigate if resistance training (RT), performed with individualized recovery between sessions (RT-IND), promotes greater gains in strength and muscle mass and reduces the variability on adaptations compared to RT with fixed recovery intervals (RT-FIX). Twenty young men (age 21.9 ± 3.3 years) were randomized in the RT-IND and RT-FIX groups. Five days before the beginning of the training, measurements of the root mean square of successive R-R intervals differences (RMSSD) values of each individual were performed to establish the baseline values. Before each RT session, the RMSSD values determined whether the participants from RT-IND protocol were recovered from the previous session. Participants performed the RT session only if RMSSD values had returned to the baseline, otherwise they had to wait for an additional 24 h. RT-FIX performed an RT session every 48 h. Muscle strength was measured by one-maximal repetition (1-RM) test and muscle cross-section area (CSA) of the vastus laterals by ultrasonography were assessed pre-and post-training. 1-RM values increased significantly from pre to post-training for both groups (RT-IND: 30% and RT-FIX: 42%, main time effect, P < 0001), with no significant difference between groups. Muscle CSA increased significantly from pre to post-training (RT-IND: 15.7% and RT-FIX: 15.8%, main time effect, P < 0001), with no significant difference between groups. In conclusion, RT-IND did not increase the gains in muscle strength and mass neither reduce the variability in muscle adaptations when compared to the RT-FIX.

Resumo Esse trabalho, tendo como referência a trajetória do Ensino Médio brasileiro nos últimos 16 anos, destaca os limites do financiamento público à edificação do Ensino Médio Integrado. Apoiando-se em uma literatura sobre o Ensino Médio e a Educação Profissional que defende a escola unitária, analisam-se dados concernentes à última etapa da Educação Básica, particularmente das escolas das redes estaduais. Argumenta-se que a intervenção do governo federal brasileiro no financiamento da Educação é um grande obstáculo à efetivação do Ensino Médio Integrado, uma vez que, independentemente do viés ideológico ou do pertencimento partidário daquele que dirige a nação, não se tem colocado essa etapa da Educação Básica como prioridade no raio do financiamento estatal. Registra-se a hegemonia das escolas estaduais na oferta do Ensino Médio e o aumento nas quais há a integração entre o Ensino Médio e a Educação Profissional. Por último, afirma-se que embora o FUNDEB represente uma ação que contemple o Ensino Médio como alvo do financiamento público dos estados, não gerará recursos suficientes para garantir o financiamento da última etapa da Educação Básica, principalmente na modalidade integrada à Educação Profissional. Conclui-se defendendo uma modificação do papel do governo federal no financiamento do Ensino Médio, de forma a garantir que a articulação entre a formação técnica e a formação geral possa universalizar-se e com melhor qualidade nas escolas estaduais. Palavras-chaveEnsino Médio Integrado -Financiamento da Educação -Ensino Técnico.

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