Effect Of Concurrent Training With Blood Flow Restriction In The Elderly

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The aim of this present study was to investigate on the effects of concurrent training with blood flow restriction (BFR-CT) and concurrent training (CT) on the aerobic fitness, muscle mass and muscle strength in a cohort of older individuals. 25 healthy older adults (64.7 +/- 4.1years; 69.33 +/- 10.8 kg; 1.6 +/- 0.1m) were randomly assigned to experimental groups: CT (n=8, endurance training (ET), 2 days/week for 30-40min, 50-80% VO2peak and RT, 2 days/week, leg press with 4 sets of 10 reps at 70-80% of 1-RM with 60s rest), BFR-CT (n=10, ET, similar to CT, but resistance training with blood flow restriction: 2 days/week, leg press with 1 set of 30 and 3 sets of 15 reps at 20-30% 1-RM with 60s rest) or control group (n=7). Quadriceps cross-sectional area (CSAq), 1-RM and VO2peak were assessed pre- and post-examination (12 wk). The CT and BFR-CT showed similar increases in CSAq post-test (7.3%, P<0.001; 7.6%, P<0.0001, respectively), 1-RM (38.1%, P<0.001; 35.4%, P=0.001, respectively) and VO2peak (9.5%, P=0.04; 10.3%, P=0.02, respectively). The BFR-CT promotes similar neuromuscular and cardiorespiratory adaptations as CT.365395399Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Estiolamento, incisão na base da estaca e uso do ácido indolbutírico na propagação da caramboleira por estacas lenhosas.

Objetivou-se, neste trabalho, avaliar o efeito do estiolamento, da incisão na base da estaca e do tratamento com ácidoindolbutírico (AIB) no enraizamento de estacas lenhosas de caramboleira. As estacas foram padronizadas com um par de folhasinteiras e 12 cm de comprimento

INFLUENCE OF THE MODEL SIZE IN THE NUMERICAL DETERMINATION OF THE AVERAGE THERMAL STRESSES IN AN MMC COMPOSITE

In previous works the authors discussed some issues related to a specific metallic matrix composites (MMC), the Aluminum matrix reinforced with SiC particles (Al+SiC) which has a metal matrix (powder) mixed with ceramic particles. These materials have some advantages when used as a structural material such as their high strength and good conformability. Their properties depend, among others, on the volumetric ratio, the  particles size and distribution besides the matrix microstructure itself. Some of them are obtained at elevated temperature what produces a thermal stress state in the material. The Al+SiC is one of the later. The powder mix is extruded at 600oC and it is used at 20oC. Several numerical analyses were performed considering the random distribution of the particles and a non-linear behavior in the aluminum matrix. The results showed strong influence of the aluminum elastic-plastic behavior in the composite thermal stress distribution due to its manufacturing process. However, one issue remained: the size of the model. It represents the central portion of a Al+SiC bar which is only about 10 times the size of a single particle (~10L). The present work investigates, always numerically, the influence of the model size on the thermal stress distribution. It considers 2 sets of non-linear analyses with random distributed particles: one with 20 models with size of 20L each one, the other set with another 20 models with size 40L. This approach allows a view of the results tendency compared with the 10L ones. As done before, the modeled volumetric ratio has a very tight range of values with its average very near to the value in an actual Al+SiC composite. It is showed that the first model size was already enough to get good results without sacrificing neither the computer nor the analyst time

Diferentes substratos na produção de porta-enxertos de caramboleira.

Objetivou-se com o presente estudo verificar a influência de diferentes substratos na produção de porta-enxertos de caramboleira. As sementes foram extraídas de frutos maduros de carambola cultívar Malásía, lavadas em água corrente e semeadas em bandejas de poliestireno (72 células, capacidade de 120 cm3/célula), contendo os seguintes substratos: vermículita, Plantmax, Rendmax, terra de barranco, areia e terra + areia (1:1, 2:1 e 1:2 v/v). Em seguída, as bandejas foram colocadas em ambiente coberto por sombrite com 50 % de lurninosidade, efetuando-se regas manuais diárias. Após 130 dias da semeadura, foram coletados os seguintes dados biométricos: porcentagem de plantas vivas, altura das plântulas, comprimento das raízes e número de folhas. Concluiu-se que a mistura terra + areia (1:1 v/v) foi mais eficiente na germinação de sementes e formação inicial de porta-enxertos de caramboleira

Effect Of Concurrent Training With Blood Flow Restriction In The Elderly.

The aim of this present study was to investigate on the effects of concurrent training with blood flow restriction (BFR-CT) and concurrent training (CT) on the aerobic fitness, muscle mass and muscle strength in a cohort of older individuals. 25 healthy older adults (64.7±4.1 years; 69.33±10.8 kg; 1.6±0.1 m) were randomly assigned to experimental groups: CT (n=8, endurance training (ET), 2 days/week for 30-40 min, 50-80% VO2peak and RT, 2 days/week, leg press with 4 sets of 10 reps at 70-80% of 1-RM with 60 s rest), BFR-CT (n=10, ET, similar to CT, but resistance training with blood flow restriction: 2 days/week, leg press with 1 set of 30 and 3 sets of 15 reps at 20-30% 1-RM with 60 s rest) or control group (n=7). Quadriceps cross-sectional area (CSAq), 1-RM and VO2peak were assessed pre- and post-examination (12 wk). The CT and BFR-CT showed similar increases in CSAq post-test (7.3%, P<0.001; 7.6%, P<0.0001, respectively), 1-RM (38.1%, P<0.001; 35.4%, P=0.001, respectively) and VO2peak (9.5%, P=0.04; 10.3%, P=0.02, respectively). The BFR-CT promotes similar neuromuscular and cardiorespiratory adaptations as CT

The Association Between Muscle Deoxygenation and Muscle Hypertrophy to Blood Flow Restricted Training Performed at High and Low Loads

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 (CSAecho) 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, CSAecho, CSAecho/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