Thiago Torres da Matta

Comparison Between Nonlinear and Linear Periodized Resistance Training: Hypertrophic and Strength Effects

Abstract Simão, R, Spineti, J, de Salles, BF, Matta, T, Fernandes, L, Fleck, SJ, Rhea, MR, and Strom-Olsen, HE. Comparison between nonlinear and linear periodized resistance training: hypertrophic and strength effects. J Strength Cond Res 26(5): 1389–1395, 2012—The aim of this study was to investigate the effects of nonlinear periodized (NLP) and linear periodized (LP) resistance training (RT) on muscle thickness (MT) and strength, measured by an ultrasound technique and 1 repetition maximum (1RM), respectively. Thirty untrained men were randomly assigned to 3 groups: NLP (n = 11, age: 30.2 ± 1.1 years, height: 173.6 ± 7.2 cm, weight: 79.5 ± 13.1 kg), LP (n = 10, age: 29.8 ± 1.9 years, height: 172.0 ± 6.8 cm, weight: 79.9 ± 10.6 kg), and control group (CG; n = 9, age: 25.9 ± 3.6 years, height: 171.2 ± 6.3 cm, weight: 73.9 ± 9.9 kg). The right biceps and triceps MT and 1RM strength for the exercises bench press (BP), lat-pull down, triceps extension, and biceps curl (BC) were assessed before and after 12 weeks of training. The NLP program varied training biweekly during weeks 1–6 and on a daily basis during weeks 7–12. The LP program followed a pattern of intensity and volume changes every 4 weeks. The CG did not engage in any RT. Posttraining, both trained groups presented significant 1RM strength gains in all exercises (with the exception of the BP in LP). The 1RM of the NLP group was significantly higher than LP for BP and BC posttraining. There were no significant differences in biceps and triceps MT between baseline and posttraining for any group; however, posttraining, there were significant differences in biceps and triceps MT between NLP and the CG. The effect sizes were higher in NLP for the majority of observed variables. In conclusion, both LP and NLP are effective, but NLP may lead to greater gains in 1RM and MT over a 12-week training period.

Reliability of the rectus femoris muscle cross-sectional area measurements by ultrasonography

The skeletal muscle system can adapt to an external stimulus from either physiological or pathological conditions. This plasticity is measured by imaging techniques such as magnetic resonance imaging or ultrasound. The anatomical cross‐sectional area of a muscle is one of the muscle architecture parameters that relates to the maximum muscle strength. The aim of this study was to determine the reliability of anatomical cross‐sectional area rectus femoris measurements, obtained by ultrasound, with two different protocols. Acquisition of four anatomical cross‐sectional area images of the right rectus femoris in two distinct regions (15 cm above the patella and 50% of the thigh length) was performed in 2 days, from a group of 15 young healthy subjects. The cross‐sectional area of each image was measured five times. The reliability of the anatomical cross‐sectional area measures was determined by the coefficient of variation (CV), intraclass correlation coefficient (ICC) and typical error of measurement (TEM). In each protocol, there were no significant differences between the means of anatomical cross‐sectional area in measurements, images and days (P>0·05). The CVs were 8·53% and 8·9%, the ICCs 0·88 and 0·87 and the TEMs 65·59 and 94·25 between the 2 days in the regions of 15 cm and 50% of the thigh length, respectively. The average values of the cross‐sectional area at 50% of the thigh length were significantly higher than those for at 15 cm above the patella (P<0·001). The measurement of rectus femoris anatomical cross‐sectional area by ultrasound proved reliable.

Strength training's chronic effects on muscle architecture parameters of different arm sites.

Matta, T, Simão, R, de Salles, BF, Spineti, J, and Oliveira, LF. Strength trainings chronic effects on muscle architecture parameters of different arm sites. J Strength Cond Res 25(6): 1711-1717, 2011—Strength training generates alterations in muscle geometry, which can be monitored by imaging techniques as, for example, the ultrasound (US) technique. There is no consensus about the homogeneity of hypertrophy in different muscle sites. Therefore, the purpose of this study was to compare the muscle thickness (MT) and pennation angle (PA) in 3 different sites (50, 60, and 70% of arm length) of the biceps brachii and triceps brachii after 12 weeks of strength training. Forty-nine healthy untrained men were divided into 2 groups: Training Group ([TG, n = 40] 29.90 ± 1.72 years; 79.53 ± 11.84 kg; 173 ± 0.6 cm) and Control Group (n = 9 25.89 ± 3.59 years; 73.96 ± 9.86 kg; 171 ± 6 cm). The TG underwent a strength training program during 12 weeks, which included exercises such as a free-weight bench press, machine lat pull-down, triceps extension in lat pull-down, and standing free-weight biceps curl with a straight bar. A US apparatus was used to measure the PA and MT at the 3 sites. The maximal voluntary isometric contraction (MVC) test was conducted for each muscle group. After 12 weeks of training, a significant difference was observed between MT in biceps brachii, with an improvement of 12% in the proximal site, whereas the distal site increased by only 4.7% (p < 0.05). For the long head of the triceps brachii, the MT and PA at the 3 sites presented significant increases, but no significant variation was observed among them, probably because of the pennated-fiber arrangement. The MVC increased significantly for both muscle groups. The results indicated that the strength training program was efficient in promoting hypertrophy in both muscles, but with dissimilar responses of the pennated and fusiform muscle architecture at different arm sites.

Influence of Exercise Order on Maximum Strength and Muscle Volume in Nonlinear Periodized Resistance Training

Spineti, J, Freitas de Salles, B, Rhea, MR, Lavigne, D, Matta, T, Miranda, F, Fernandes, L, and Simão, R. Influence of exercise order on maximum strength and muscle volume in nonlinear periodized resistance training. J Strength Cond Res 24(11): 2962-2969, 2010-The purpose of this study was to examine the influence of exercise order on strength and muscle volume (MV) after 12 weeks of nonlinear periodized resistance training. The participants were randomly assigned into 3 groups. One group began performing large muscle group exercises and progressed to small muscle group exercises (LG-SM), whereas another group started with small muscle group exercises and advanced to large muscle group exercises (SM-LG). The exercise order for LG-SM was bench press (BP), machine lat pull-down (LPD), triceps extension (TE), and biceps curl (BC). The order for the SM-LG was BC, TE, LPD, and BP. The third group did not exercise and served as a control group (CG). Training frequency was 2 sessions per week with at least 72 hours of rest between sessions. Muscle volume was assessed at baseline and after 6 weeks and 12 weeks of training by ultrasound techniques. One repetition maximum strength for all exercises was assessed at baseline and after 12 weeks of training. Effect size data demonstrated that differences in strength and MV were exhibited based on exercise order. Both training groups demonstrated greater strength improvements than the CG, but only BP strength increased to a greater magnitude in the LG-SM group as compared with the SM-LG. In all other strength measures (LPD, TE, and BC), the SM-LG group showed significantly greater strength increases. Triceps MV increased in the SM-LG group; however, biceps MV did not differ significantly between the training groups. In conclusion, if an exercise is important for the training goals of a program, then it should be placed at the beginning of the training session, regardless of whether or not it is a large muscle group exercise or a small muscle group exercise.

Interpretation of the mechanisms related to the muscular strength gradation through accelerometry

The aim of this study was to characterize the temporal and spectral components of the muscle contractions in different contraction levels through the accelerometry. Fifteen male and twelve female right-handed individuals participated in this study. The trial was constituted by a maximal workload (MW) test that allowed to determine five different workloads (20%, 40%, 60%, 80% and 100% of MW) which, by its turn, allowed to determine five percentage workloads during the strength test (20%, 40%, 60%, 80%, and 100% of the MW) in isometry during eight seconds each of them. A biaxial accelerometer was put on the muscular abdomen of the right brachii biceps muscle. The mean square root (RMS value), a temporal parameter, and the mean frequency (MFE), a spectral parameter were extracted from the accelerometry signals (MMG signals). Such parameters were analyzed towards the X (perpendicular to the fibers) and Y (parallel to the fibers) directions. Both groups presented a descent behavior pattern of the loaded MFE (Y), and the most accentuated was the female group. The MFE variable (X) in the female group presented similar behavior before the MFE (Y), and it was observed a statistically significant difference only between 20% of the MW and every other workload (p = 0.0022 for 40% and p < 0.0001 for the remaining). The male group did not present any statistically significant difference between workloads. The RMS value (Y) presented an ascent behavior with the workload in both genders, presenting differences between the 20% and 40% workloads of the MW (p = 0.000), and 80% and 100% of the MW (p = 0.01) in the male group. But it was observed no statistically significant difference between workloads in the female group. It is argued that during the muscular contraction, there is non-uniform variations on the fibers diameter, besides the low frequency lateral oscillations. Such information seems to have strong correlation between the type of the fibers, and this could contribute for a better clarification on the possible mechanisms involved in the gradation process of the muscular strength.O objetivo deste estudo foi caracterizar as componentes temporais e espectrais dos abalos musculares em diferentes niveis de contracao muscular atraves da acelerometria. Participaram do estudo 15 individuos do sexo masculino e 12 do feminino, todos destros. O experimento constou de um teste de carga maxima (CM) que permitiu determinar cinco cargas percentuais administradas durante os testes de forca (20%, 40%, 60%, 80% e 100% da CM), em isometria e por oito segundos cada. Um acelerometro biaxial foi colocado sobre o ventre muscular do biceps braquial direito. A raiz media quadratica (valor RMS), um parâmetro temporal, e a frequencia media (FME), um parâmetro espectral, foram extraidas dos sinais de acelerometria (sinal de MMG). Estes parâmetros foram analisados nas direcoes X (perpendicular as fibras) e Y (paralela as fibras). Ambos os grupos apresentaram comportamento decrescente da FME (Y) com a carga, sendo mais pronunciado para o grupo feminino. A variavel FME (X), no grupo feminino, apresentou comportamento semelhante a FME (Y), sendo apenas observada diferenca estatistica significativa entre 20% da CM e todas as demais cargas (p = 0,0022 para 40% e p < 0,0001 para as demais). O grupo masculino nao apresentou diferenca estatistica significativa entre as cargas. O valor RMS (Y) apresentou comportamento crescente com a carga para ambos os grupos, havendo diferencas entre as cargas de 20% e 40% da CM (p = 0,000) e 80%, e 100% da CM (p = 0,01) para o grupo masculino. No entanto, nao foi observada diferenca estatistica significativa entre as cargas para o grupo feminino. Discute-se que durante a contracao muscular ocorrem variacoes nao uniformes do diâmetro da fibra, alem de oscilacoes laterais de baixa frequencia. Estas informacoes parecem ter forte correlacao com a tipagem de fibras, o que poderia contribuir para melhor esclarecer os possiveis mecanismos envolvidos durante o processo de gradacao da forca muscular.

Heterogeneity of rectus femoris muscle architectural adaptations after two different 14-week resistance training programmes

This study aimed to determine the architectural changes of rectus femoris muscle at distinctive sites of the thigh length after two different 14‐week resistance training programmes.

Interpretação dos mecanismos de gradação da força muscular através da acelerometria

The aim of this study was to characterize the temporal and spectral components of the muscle contractions in different contraction levels through the accelerometry. Fifteen male and twelve female right-handed individuals participated in this study. The trial was constituted by a maximal workload (MW) test that allowed to determine five different workloads (20%, 40%, 60%, 80% and 100% of MW) which, by its turn, allowed to determine five percentage workloads during the strength test (20%, 40%, 60%, 80%, and 100% of the MW) in isometry during eight seconds each of them. A biaxial accelerometer was put on the muscular abdomen of the right brachii biceps muscle. The mean square root (RMS value), a temporal parameter, and the mean frequency (MFE), a spectral parameter were extracted from the accelerometry signals (MMG signals). Such parameters were analyzed towards the X (perpendicular to the fibers) and Y (parallel to the fibers) directions. Both groups presented a descent behavior pattern of the loaded MFE (Y), and the most accentuated was the female group. The MFE variable (X) in the female group presented similar behavior before the MFE (Y), and it was observed a statistically significant difference only between 20% of the MW and every other workload (p = 0.0022 for 40% and p < 0.0001 for the remaining). The male group did not present any statistically significant difference between workloads. The RMS value (Y) presented an ascent behavior with the workload in both genders, presenting differences between the 20% and 40% workloads of the MW (p = 0.000), and 80% and 100% of the MW (p = 0.01) in the male group. But it was observed no statistically significant difference between workloads in the female group. It is argued that during the muscular contraction, there is non-uniform variations on the fibers diameter, besides the low frequency lateral oscillations. Such information seems to have strong correlation between the type of the fibers, and this could contribute for a better clarification on the possible mechanisms involved in the gradation process of the muscular strength.O objetivo deste estudo foi caracterizar as componentes temporais e espectrais dos abalos musculares em diferentes niveis de contracao muscular atraves da acelerometria. Participaram do estudo 15 individuos do sexo masculino e 12 do feminino, todos destros. O experimento constou de um teste de carga maxima (CM) que permitiu determinar cinco cargas percentuais administradas durante os testes de forca (20%, 40%, 60%, 80% e 100% da CM), em isometria e por oito segundos cada. Um acelerometro biaxial foi colocado sobre o ventre muscular do biceps braquial direito. A raiz media quadratica (valor RMS), um parâmetro temporal, e a frequencia media (FME), um parâmetro espectral, foram extraidas dos sinais de acelerometria (sinal de MMG). Estes parâmetros foram analisados nas direcoes X (perpendicular as fibras) e Y (paralela as fibras). Ambos os grupos apresentaram comportamento decrescente da FME (Y) com a carga, sendo mais pronunciado para o grupo feminino. A variavel FME (X), no grupo feminino, apresentou comportamento semelhante a FME (Y), sendo apenas observada diferenca estatistica significativa entre 20% da CM e todas as demais cargas (p = 0,0022 para 40% e p < 0,0001 para as demais). O grupo masculino nao apresentou diferenca estatistica significativa entre as cargas. O valor RMS (Y) apresentou comportamento crescente com a carga para ambos os grupos, havendo diferencas entre as cargas de 20% e 40% da CM (p = 0,000) e 80%, e 100% da CM (p = 0,01) para o grupo masculino. No entanto, nao foi observada diferenca estatistica significativa entre as cargas para o grupo feminino. Discute-se que durante a contracao muscular ocorrem variacoes nao uniformes do diâmetro da fibra, alem de oscilacoes laterais de baixa frequencia. Estas informacoes parecem ter forte correlacao com a tipagem de fibras, o que poderia contribuir para melhor esclarecer os possiveis mecanismos envolvidos durante o processo de gradacao da forca muscular.

Lumbar multifidus and erector spinae electromyograms during back bridge exercise in time and frequency domains.

BACKGROUND Muscle activity is studied during trunk stabilization exercises using electromyograms (EMG) in time domain. However, the frequency domain analysis provides information that would be important to understand fatigue process. OBJECTIVE To assess EMG of lumbar multifidus (LM) and erector spinae (ES) muscles, in time and frequency domains, during back bridge exercise. METHODS Nineteen healthy young men performed the exercise for one minute and EMG was monitored by surface electromyography. Normalized root mean square (RMS) value and spectral median frequency (MF) were compared between beginning and final epochs of test. The dynamics of the MF during whole test was also obtained by short-time Fourier transform. RESULTS RMS values were about 30% of maximum voluntary contraction, and LM muscle showed greater MF than ES, which did not decrease at the final of exercise. However, the slope of MF was significant mainly for LM. CONCLUSIONS Muscle activation of 30% is sufficient to keep lumbar stability and is suitable to improve muscular endurance. The significance of MF slope without decreasing at the final of exercise indicates challenging muscular endurance without imply on high fatigability. Due to lower muscular demand, this exercise might be recommended for trunk stabilizing for low back pain patients.

Selective hypertrophy of the quadriceps musculature after 14 weeks of isokinetic and conventional resistance training

One of the fundamental adaptations observed with resistance training (RT) is muscle hypertrophy. Conventional and isokinetic machines provide different forms of mechanical stress, and it is possible that these two training modes could promote differing degrees of hypertrophic adaptations. There is a lack of data comparing the selective hypertrophy of the quadriceps musculature after training with a conventional knee extension machine versus an isokinetic machine. The purpose of this study was to evaluate the selective hypertrophy of the quadriceps musculature and knee extension maximal isometric torque after 14 weeks of conventional versus isokinetic RT. Thirty‐five men were assigned to three groups: control group and training groups (conventional and isokinetic) performed three sets of unilateral knee extensions per session with a progressive loading scheme twice a week. Prior to and following the intervention, maximal isometric knee extensor torque was measured using an isokinetic dynamometer, and muscle thickness (MT) of quadriceps femoris muscles was assessed via ultrasound. The results indicated non‐uniform changes in MT between the muscles that comprise the quadriceps femoris group. For the conventional group, significantly greater increases in rectus femoris thickness were evident versus all other quadriceps muscles (14%). For the isokinetic group, increases in RF thickness (11%) were significantly greater in comparison with the vastus intermedius only. Although the muscle thickness did not increase for all the quadriceps femoris muscles, the relative rectus femoris adaptation suggested a selective hypertrophy favouring this portion.

Reliability of ultrasound texture measures of Biceps Brachialis and Gastrocnemius Lateralis muscles' images

Ultrasound (US) is an important tool for diagnosing of many musculoskeletal tissue conditions. Image texture analysis can be used to characterize this tissue. The complexity curve (CC) is a technique commonly used to characterize the number of grey‐level transitions in an image. Variability and reliability of US texture measures in the muscle tissue are unavailable in the literature. The aim of this study was to determine the variability and reliability of five CC texture parameters from US images of healthy Biceps Brachialis and Gastrocnemius Lateralis (GL) muscles, with longitudinal and transversal orientations of the probe. Eight images per subject were obtained for 30 men in 2 days. Mean, standard deviation, coefficient of variation and intraclass correlation coefficient for the five parameters were calculated for regions of interest. Results showed that the variability was similar for both muscles and most of the parameters showed satisfactory reliability (r > 0·7) for the Biceps Brachialis with the transverse scan and for the GL with the longitudinal scan.