Effects of Resistance Training Overload Progression Protocols on Strength and Muscle Mass.

The aim of this study was to compare the effects of progressive overload in resistance training on muscle strength and cross-sectional area (CSA) by specifically comparing the impact of increasing load (LOADprog) versus an increase in repetitions (REPSprog). We used a within-subject experimental design in which 39 previously untrained young persons (20 men and 19 women) had their legs randomized to LOADprog and REPSprog. Outcomes were assessed before and after 10 weeks of training. Muscle strength was assessed using the one repetition maximum (1RM) test on the leg extension exercise, and the CSA of the vastus lateralis was assessed by ultrasonography. Both protocols increased 1RM values from pre (LOADprog: 52.90±16.32 kg; REPSprog: 51.67±15.84 kg) to post (LOADprog: 69.05±18.55 kg, REPSprog: 66.82±17.95 kg), with no difference between them (P+>+0.05). Similarly, both protocols also increased in CSA values from pre (LOADprog: 21.34±4.71 cm²; REPSprog: 21.08±4.62 cm²) to post (LOADprog: 23.53±5.41 cm², REPSprog: 23.39±5.19 cm²), with no difference between them (P+>+0.05). In conclusion, our findings indicate that the progression of overload through load or repetitions can be used to promote gains in strength and muscle hypertrophy in young men and women in the early stages of training.

Effect of Protein and Carbohydrate Combined with Resistance Training on Muscular Adaptation.

The purpose was to compare the effects of protein (whey protein) and carbohydrate supplementation and protein alone both combined with resistance training on muscle strength, muscle mass and total training volume progression in untrained young men. Resistance training was performed using the leg press and knee extension until concentric failure (8-12 repetition maximum), three times a week for eight weeks. Muscle strength and muscle cross-sectional area were assessed before and after training. Total training volume progression was calculated considering the first and eighth week. Seventeen men completed the study (protein and carbohydrate, n=9, age 23.44 ± 4.56 years, weight: 62.13±6.17 kg, height: 1.75±0.02 m, body mass index: 20.29±2.08 kg/m2; protein, n=8, age 24.63±2.39 years, weight: 69.01±5.57 kg, height: 1.77±0.07 m; body mass index: 21.64±1.05 kg/m2. Both protocols showed similar increases in muscle strength (effect size: protein and carbohydrate=1.28; protein=0.97; p<0.001), muscle cross sectional area (effect size: protein and carbohydrate=0.66; protein=0.47; p<0.001) and total training volume progression (effect size: protein and carbohydrate=2.68; protein=1.63; p<0.001) after training. No differences were found between groups p>0.05). Protein and carbohydrate supplementation combined with resistance training does not induce greater gains in muscle strength, hypertrophy and total training volume compared to resistance training combined with protein alone in untrained individuals.

Suspension training vs. traditional resistance training: effects on muscle mass, strength and functional performance in older adults.

PURPOSE: We compared the effects of suspension training (ST) with traditional resistance training (TRT) on muscle mass, strength and functional performance in older adults. METHODS: Forty-two untrained older adults were randomized in TRT, ST (both performed 3 sets of whole body exercises to muscle failure) or control group (CON). Muscle thickness (MT) of biceps brachii (MTBB) and vastus lateralis (MTVL), maximal dynamic strength test (1RM) for biceps curl (1RMBC) and leg extension exercises (1RMLE), and functional performance tests (chair stand [CS], timed up and go [TUG] and maximal gait speed [MGS]) were performed before and after 12 weeks of training. RESULTS: MTBB increased significantly and similarly for all training groups (TRT 23.35%; ST 21.56%). MTVL increased significantly and similarly for all training groups (TRT 13.03%; ST 14.07%). 1RMBC increased significantly and similarly for all training groups (TRT 16.06%; ST 14.33%). 1RMLE increased significantly and similarly for all training groups (TRT 14.89%; ST 18.06%). MGS increased significantly and similarly for all groups (TRT 6.26%; ST 5.99%; CON 2.87%). CS decreased significantly and similarly for all training groups (TRT - 20.80%; ST - 15.73%). TUG decreased significantly and similarly for all training groups (TRT - 8.66%; ST - 9.16%). CONCLUSION: Suspension training (ST) promotes similar muscle mass, strength and functional performance improvements compared to TRT in older adults.

Self-selected vs. Fixed Repetition Duration: Effects on Number of Repetitions and Muscle Activation in Resistance-Trained Men.

Nóbrega, SR, Barroso, R, Ugrinowitsch, C, da Costa, JLF, Alvarez, IF, Barcelos, C, and Libardi, CA. Self-selected vs. fixed repetition duration: effects on number of repetitions and muscle activation in resistance-trained men. J Strength Cond Res 32(9): 2419-2424, 2018-The aim of this study was to compare the effects of self-selected and fixed repetition duration (RD) on resistance exercise (RE) volume, muscle activation, and time under tension (TUT) per repetition and per session. Twelve resistance-trained men participated in the study. A randomized cross-over design was used and each participant performed 2 high-intensity RE protocols in a balanced order: (a) 3 sets of RE with self-selected RD (SELF); and (b) 3 sets of RE with fixed RD (2-second concentric and 2-second eccentric [FIX]). Muscle activation was assessed through surface electromyography (EMG) of the vastus lateralis and vastus medialis throughout RE sessions. Overall, RE volume was significantly greater for SELF (p = 0.01), whereas TUT per repetition was significantly greater for FIX (p = 0.0001). No significant differences between protocols were detected for TUT per session. Between-protocol comparisons revealed significantly greater EMG amplitude for SELF compared with FIX at S1 (p = 0.01), S2 (p = 0.03), and S3 (p = 0.03). Both SELF and FIX protocols produced significant increases in EMG amplitude from 25 to 100% (p < 0.001) of set completion. Between-protocol comparisons revealed significantly greater EMG amplitude for SELF compared with FIX at 75% (p = 0.03) and 100% (p = 0.01). In conclusion, self-selected RD resulted in greater volume and muscle activation compared with fixed RD in an RE session.

Application of Artificial Intelligence to Automate the Reconstruction of Muscle Cross-Sectional Area Obtained by Ultrasound.

PURPOSE: Manual reconstruction (MR) of the vastus lateralis (VL) muscle cross sectional area (CSA) from sequential ultrasound (US) images is accessible, reproducible and has concurrent validity with magnetic resonance imaging. However, this technique requires numerous controls and procedures during image acquisition and reconstruction, making it laborious and time-consuming. The aim of this study was to determine the concurrent validity of VL CSA assessments between MR and computer vision-based automatic reconstruction (AR) of CSA from sequential images of the VL obtained by US. METHODS: The images from each sequence were manually rotated to align the fascia between images and thus visualize the VL CSA. For the AR, an artificial neural network model was utilized to segment areas of interest in the image, such as skin, fascia, deep aponeurosis, and femur. This segmentation was crucial to impose necessary constraints for the main assembly phase. At this stage, an image registration application, combined with differential evolution, was employed to achieve appropriate adjustments between the images. Next, the VL CSA obtained from the MR (n = 488) and AR (n = 488) techniques were used to determine their concurrent validity. RESULTS: Our findings demonstrated a low coefficient of variation (CV) (1.51%) for AR compared to MR. The Bland-Altman plot showed low bias and close limits of agreement (+1.18 cm2, -1.19 cm2), containing more than 95% of the data points. CONCLUSIONS: The AR technique is valid compared to MR when measuring VL CSA in a heterogeneous sample.

Resistance training combined with blood flow restriction in cirrhosis: study protocol for a randomized controlled trial.

BACKGROUND: Patients affected by hepatic cirrhosis show reductions in muscle mass and function, with poor quality of life and functional performance. As such, resistance training with blood flow restriction (BFR-RT) could be a useful therapeutic tool for health promotion. Thus, we aim to verify the effects of this intervention on muscle strength, muscle mass, fiber Pennation angle, fascicle length, functional performance, quality of life, and fall risk scores in this population. METHODS: Thirty participants will be randomly distributed between 1) BFR-RT and 2) control (CTRL). Assessments will occur at three time points: before the training intervention (0 W), after 12 weeks (12 W), and at follow-up (24 W). The following variables will be assessed: Child-Pugh classification; MELD score; SF-36 questionnaire; fatigue severity index; 6-min walk test; timed-up and go; 30-s sitting and rising test; dietary record; one-repetition maximum (1-RM) strength test (knee extension exercise); and vastus lateralis' cross-sectional area, Pennation angle, and fascicle length. The BFR-RT group will undergo 12 weeks of knee extension exercise (1 × 30 repetitions and 3 × 15 repetitions at 20% 1-RM and 50% of total blood flow occlusion pressure), with two sessions per week. Data normality will be assessed using the Shapiro-Wilk test. In case of normal distribution, a one-way repeated measures analysis of variance will be implemented to test for differences in baseline values. A mixed model then will be applied for each dependent variable. In case of non-normal data distribution, a Kruskal-Wallis test will be implemented to test for differences in baseline values. Next, the Friedman test will be used to analyze repeated measures. Within- and between-group effect sizes will be calculated using Cohen's d for each outcome. Finally, the minimal clinically important difference will be analyzed with distribution-based methods. DISCUSSION: To our knowledge, this will be the first trial to investigate BFR-RT in patients with cirrhosis and evaluate the effects on neuromuscular parameters, functional performance, disease severity, and quality of life outcomes. TRIAL REGISTRATION: Brazilian Clinical Trials Registry (ReBec): RBR-395mfw. Registered on 25 August 2018.

High-frequency resistance training does not promote greater muscular adaptations compared to low frequencies in young untrained men.

The aim of the study was to compare the effect of resistance training (RT) frequencies of five times (RT5), thrice- (RT3) or twice- (RT2) weekly in muscle strength and hypertrophy in young men. Were used a within-subjects design in which 20 participants had one leg randomly assigned to RT5 and the other to RT3 or to RT2. 1 RM and muscle cross-sectional area (CSA) were assessed at baseline, after four (W4) and eight (W8) RT weeks. RT5 resulted in greater total training volume (TTV) than RT3 and RT2 (P = .001). 1 RM increased similarly between protocols at W4 (RT5: 55 ± 9 Kg, effect size (ES): 1.18; RT3: 51 ± 11 Kg, ES: 0.80; RT2: 54 ± 7 Kg, ES: 1.13; P < .0001) and W8 (RT5: 62 ± 11 Kg, ES: 1.81; RT3: 57 ± 11 Kg, ES: 1.40; RT2: 60 ± 8 Kg, ES: 1.98; P < .0001) vs. baseline (RT5: 45 ± 9 Kg; RT3: 42 ± 11 Kg; RT2: 46 ± 7 Kg). CSA increased similarly between protocols at W4 (RT5: 24.6 ± 3.9 cm2, ES: 0.54; RT3: 22.0 ± 4.6 cm2, ES: 0.19; RT2: ES: 0.25; 23.8 ± 3.8 cm2; P < .001), and W8 (RT5: 25.3 ± 4.3 cm2; ES: 0.69; RT3: 23.6 ± 4.2 cm2, ES: 0.58; RT2: 25.5 ± 3.7 cm2; ES: 0.70; P < .0001) vs. baseline (RT5: 22.5 ± 3.8 cm2; RT3: 21.2 ± 4.0 cm2; RT2: 22.9 ± 3.8 cm2). Performing RT5, RT3 and RT2 a week result in similar muscle strength increase and hypertrophy, despite higher TTV for RT5.

Efeitos da fisioterapia na força, atividade mioelétrica e dor, em lombálgicos crônicos / Effects of physical therapy in strength, myoelectric activity and pain, in chronic low back pain

Introdução: A dor lombar promove hipotrofia, alterações do controle motor e instabilidade lombar, necessitando de adequado tratamento. Objetivo: Analisar o efeito do tratamento fisioterapêutico na força de extensão do tronco, na atividade elétrica dos músculos transverso abdominal (TrA) e multífido lombar (ML) e na dor em lombálgicos crônicos. Métodos: Foram avaliados 19 voluntários pré e póstratamento fisioterapêutico quanto a força de extensão do tronco, atividade mioelétrica (TrA e ML), e dor. Resultados: Não houve alteração na força de extensão do tronco (p=0,064); a atividade eletromiográfica apresentou diferença no ML, dos lados direito (p<0,01) e esquerdo (p<0,05) durante o repouso na comparação pré e pós, e no TrA (p<0,05) no repouso, pré tratamento; a dor apresentou diminuição significativa pós-tratamento (p<0,001). Conclusão: O tratamento fisioterapêutico aplicado não alterou a força e teve pouco efeito na atividade mioelétrica do ML e TrA, no entanto, reduziu drasticamente o quadro álgico.

Introduction: Low back pain leads to hypotrophy, changes in motor control and lumbar instability, requiring appropriate treatment. Objective: To analyze the effect of physiotherapy on the strength of upper body extension, electric activity of the TrA and ML muscles and pain in patients with chronic low back pain. Methods: Nineteen volunteers were pre and post physical therapy evaluated in the upper body extension strength, electric activity (TrA and ML) and pain.Results: There was no change in upper body extension strength (p=0.064); the was difference in ML electromyographic activity, on the right side (p<0.01) and left (p<0.05) at rest in pre and post comparison and in TrA (p<0,05) at rest pre treatment; pain post treatment showed significant reduction (p<0,001). Conclusion: The physical therapy treatment applied did not change the strength and had little effect on myoeletric activity of the ML and TrA, however, drastically reduced the painful condition.

Alterações termográficas na lombalgia crônica sob tratamento fisioterapêutico: ensaio clínico controlado e randomizado / Thermographic changes in chronic low back pain under physiotherapeutic treatment: controlled and randomized clinical trial

Objetivo: Analisar as alterações termográficas em pacientes com lombalgia crônica sob diferentes intervenções fisioterapêuticas. Método: Selecionaram-se 33 indivíduos com lombalgia crônica que foram aleatorizados em quatro grupos: terapia manual (gTM; n=10); estabilização segmentar lombar (gESL; n=7); terapia combinada ­ TM + ESL (gTC; n=7); e orientações posturais/controle (gOP; n=9). Todos realizaram dez sessões fisioterapêuticas e avaliados, pré- e pós-tratamento, quanto à temperatura cutânea (termografia infravermelha) e dor (Escala Visual Analógica ­ EVA) na região lombar. Utilizou-se Anova (4x3x2) para comparar quatro grupos, três áreas (ALE, AC e ALD) e duas avaliações (pré- e pós- tratamento), para temperatura cutânea; e Anova (4x2) entre os quatro grupos, pré- e pós-tratamento, para a EVA, considerando α≤5%. Resultados: Não houve diferença significativa na temperatura da região lombar, comparando-se pré- e pós-tratamento; contudo, a EVA mostrou redução significativa para os grupos (P≤0,01). Conclusão: Apesar dos tratamentos não terem minimizado a temperatura na região lombar, diminuíram, drasticamente, o nível de dor nos grupos.

Objective: To analyze the thermographic changes in patients with chronic low back pain under different physical therapy interventions. Method: Thirty three chronic low back pain individuals were randomized into four groups: manual therapy (MTg; n=10), lumbar stabilization (LSg; n=7); combined therapy ­ MT + LS (CTg; n=7) and postural orientation/control (PGg; n=9). All individuals underwent ten physiotherapy sessions and evaluated pre- and post-treatment as skin temperature (infrared thermography), and pain in the lower back (Visual Analogue Scale ­ VAS). Anova (4x3x2) comparing four groups, three areas (LLA, CA and RLA) and two evaluations (pre- and post-treatment) for skin temperature; and Anova (4x2) between the four groups, pre- and post-treatment, were used for VAS, considering α ≤5%. Results: There was no significant difference in lower back temperature, comparing pre- and post-treatment; however, the VAS showed a significant reduction for all groups (P≤0.01). Conclusion: Although the treatments have not minimized the temperature in the lumbar region, they were able to decrease dramatically the level of pain, in all groups.