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  • Author: Brad J. Schoenfeld x
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Bret Contreras, Andrew D. Vigotsky, Brad J. Schoenfeld, Chris Beardsley and John Cronin

Bridging exercise variations are well researched and commonly employed for both rehabilitation and sport performance. However, resisted bridge exercise variations have not yet been compared in a controlled experimental study. Therefore, the purpose of this study was to compare the differences in upper and lower gluteus maximus, biceps femoris, and vastus lateralis electromyography (EMG) amplitude for the barbell, band, and American hip thrust variations. Thirteen healthy female subjects (age = 28.9 y; height = 164.3 cm; body mass = 58.2 kg) familiar with the hip thrust performed 10 repetitions of their 10-repetition maximum of each variation in a counterbalanced and randomized order. The barbell hip thrust variation elicited statistically greater mean gluteus maximus EMG amplitude than the American and band hip thrusts, and statistically greater peak gluteus maximus EMG amplitude than the band hip thrust (P ≤ .05), but no other statistical differences were observed. It is recommended that resisted bridging exercise be prescribed according to the individual’s preferences and desired outcomes.

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Bret Contreras, Andrew D. Vigotsky, Brad J. Schoenfeld, Chris Beardsley and John Cronin

Front, full, and parallel squats are some of the most popular squat variations. The purpose of this investigation was to compare mean and peak electromyography (EMG) amplitude of the upper gluteus maximus, lower gluteus maximus, biceps femoris, and vastus lateralis of front, full, and parallel squats. Thirteen healthy women (age = 28.9 ± 5.1 y; height = 164 ± 6.3 cm; body mass = 58.2 ± 6.4 kg) performed 10 repetitions of their estimated 10-repetition maximum of each respective variation. There were no statistical (P = .05) differences between full, front, and parallel squats in any of the tested muscles. Given these findings, it can be concluded that the front, full, or parallel squat can be performed for similar EMG amplitudes. However, given the results of previous research, it is recommended that individuals use a full range of motion when squatting, assuming full range can be safely achieved, to promote more favorable training adaptations. Furthermore, despite requiring lighter loads, the front squat may provide a similar training stimulus to the back squat.

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Bret Contreras, Andrew D. Vigotsky, Brad J. Schoenfeld, Chris Beardsley and John Cronin

The back squat and barbell hip thrust are both popular exercises used to target the lower body musculature; however, these exercises have yet to be compared. Therefore, the purpose of this study was to compare the surface electromyographic (EMG) activity of the upper and lower gluteus maximus, biceps femoris, and vastus lateralis between the back squat and barbell hip thrust. Thirteen trained women (n = 13; age = 28.9 years; height = 164 cm; mass = 58.2 kg) performed estimated 10-repetition maximums (RM) in the back squat and barbell hip thrust. The barbell hip thrust elicited significantly greater mean (69.5% vs 29.4%) and peak (172% vs 84.9%) upper gluteus maximus, mean (86.8% vs 45.4%) and peak (216% vs 130%) lower gluteus maximus, and mean (40.8% vs 14.9%) and peak (86.9% vs 37.5%) biceps femoris EMG activity than the back squat. There were no significant differences in mean (99.5% vs 110%) or peak (216% vs 244%) vastus lateralis EMG activity. The barbell hip thrust activates the gluteus maximus and biceps femoris to a greater degree than the back squat when using estimated 10RM loads. Longitudinal training studies are needed to determine if this enhanced activation correlates with increased strength, hypertrophy, and performance.

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Jozo Grgic, Filip Sabol, Sandro Venier, Ivan Mikulic, Nenad Bratkovic, Brad J. Schoenfeld, Craig Pickering, David J. Bishop, Zeljko Pedisic and Pavle Mikulic

Purpose: To explore the effects of 3 doses of caffeine on muscle strength and muscle endurance. Methods: Twenty-eight resistance-trained men completed the testing sessions under 5 conditions: no-placebo control, placebo control, and with caffeine doses of 2, 4, and 6 mg·kg−1. Muscle strength was assessed using the 1-repetition-maximum test; muscle endurance was assessed by having the participants perform a maximal number of repetitions with 60% 1-repetition maximum. Results: In comparison with both control conditions, only a caffeine dose of 2 mg·kg−1 enhanced lower-body strength (d = 0.13–0.15). In comparison with the no-placebo control condition, caffeine doses of 4 and 6 mg·kg−1 enhanced upper-body strength (d = 0.07–0.09) with a significant linear trend for the effectiveness of different doses of caffeine (P = .020). Compared with both control conditions, all 3 caffeine doses enhanced lower-body muscle endurance (d = 0.46–0.68). For upper-body muscle endurance, this study did not find significant effects of caffeine. Conclusions: This study revealed a linear trend between the dose of caffeine and its effects on upper-body strength. The study found no clear association between the dose of caffeine and the magnitude of its ergogenic effects on lower-body strength and muscle endurance. From a practical standpoint, the magnitude of caffeine’s effects on strength is of questionable relevance. A low dose of caffeine (2 mg·kg−1)—for an 80-kg individual, the dose of caffeine in 1–2 cups of coffee—may produce substantial improvements in lower-body muscle endurance with the magnitude of the effect being similar to that attained using higher doses of caffeine.

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Alex S. Ribeiro, Brad J. Schoenfeld, Danilo R.P. Silva, Fábio L.C. Pina, Débora A. Guariglia, Marcelo Porto, Nailza Maestá, Roberto C. Burini and Edilson S. Cyrino

The purpose of this study was to compare different split resistance training routines on body composition and muscular strength in elite bodybuilders. Ten male bodybuilders (26.7 ± 2.7 years, 85.3 ± 10.4 kg) were randomly assigned into one of two resistance training groups: 4 and 6 times per week (G4× and G6×, respectively), in which the individuals trained for 4 weeks, 4 sets for each exercise performing 6–12 repetitions maximum (RM) in a pyramid fashion. Body composition was assessed by dual energy X-ray absorptiometry, muscle strength was evaluated by 1RM bench-press testing. The food intake was planned by nutritionists and offered individually throughout the duration of the experiment. Significant increases (p < .05) in fat-free mass (G4× = +4.2%, G6× = +3.5%) and muscular strength (G4× = +8.4%, G6× = +11.4%) with no group by time interaction were observed. We conclude that 4 and 6 weekly sessions frequencies of resistance training promote similar increases in fat-free mass and muscular strength in elite bodybuilders.

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Alex S. Ribeiro, Luiz C. Pereira, Danilo R.P. Silva, Leandro dos Santos, Brad J. Schoenfeld, Denilson C. Teixeira, Edilson S. Cyrino and Dartagnan P. Guedes

The purpose of the study was to clarify the independent association between sedentary behavior and physical activity with multiple chronic diseases and medicine intake in older individuals. Sedentary behavior and physical activity were measured by questionnaires. Diseases and medication use were self-reported. Poisson’s regression was adopted for main analysis, through crude and adjusted prevalence ratio and confidence interval of 95%. For men, sedentary time >4 hr/day presented a 76% higher prevalence of ≥2 chronic diseases, while physical inactivity increases the likelihood of using ≥2 medicines in 95%. For women, sedentary behavior >4 hr/day presented an 82% and 43% greater prevalence for ≥2 chronic diseases and the intake of ≥2 medicines, respectively. Sedentary behavior represents an independent associated factor of multiple chronic diseases in older men and women. In addition, inactivity for men and sedentarism for women are associated with the amount of medicine intake.

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Alex S. Ribeiro, Rafael Deminice, Brad J. Schoenfeld, Crisieli M. Tomeleri, Camila S. Padilha, Danielle Venturini, Décio S. Barbosa, Luís B. Sardinha and Edilson S. Cyrino

The purpose of this study was to investigate the effect of two different resistance training (RT) systems on oxidative stress biomarkers in older women. Fifty-nine older women (67.9 ± 5.0 years) were randomly assigned to one of three groups. Two training groups performed an 8 week RT program either in traditional (TD, n = 20) or a pyramid (PR, n = 20) system 3 times per week, or a control group (CG, n = 19). The TD program consisted of 3 sets of 8–12 RM with constant load for the 3 sets, whereas the PR training consisted of 3 sets of 12/10/8 RM with incremental loads for each set. As compared with the CG, both TD and PR achieved upregulation of the antioxidant system as evidenced by higher (p < .05) values of total radical-trapping antioxidant parameter plasma concentration after intervention (TD= 930.4 ± 160.0 µmolTrolox, PR= 977.8 ± 145.2 µmolTrolox, CG= 794.4 ± 130.2 µmolTrolox). For the protein oxidation adducts, TD and PR presented lower (p < .05) scores compared with CG (TD= 91.2 ± 25.0 µmol/L, PR= 93.0 ± 30.3 µmol/L, CG= 111.0 ± 20.4 µmol/L). However, there were no differences (p < .05) between trained groups in the antioxidant capacity markers and in the protein oxidation adducts markers. The results suggest that 8 weeks of progressive RT promotes an improvement in markers of oxidative stress in older women independent of the load-management RT system.

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Alex S. Ribeiro, Matheus A. Nascimento, Brad J. Schoenfeld, João Pedro Nunes, Andreo F. Aguiar, Edilaine F. Cavalcante, Analiza M. Silva, Luís B. Sardinha, Steven J. Fleck and Edilson S. Cyrino

The main purpose of this study was to compare the effects of resistance training (RT) performed two versus three times per week on phase angle (a cellular health indicator) in older women. A total of 39 women (69.1 ± 5.5 years) were randomly assigned to perform a RT program two (G2X) or three (G3X) days per week for 12 weeks. The RT was a whole-body program (eight exercises, one set, 10–15 repetitions). Phase angle, resistance, reactance, and total body water were assessed by bioimpedance spectroscopy. Intracellular water, reactance, and phase angle increased significantly in G2X (2.1%, 3.0%, and 5.6%, respectively) and G3X (5.0%, 6.9%, and 10.3%, respectively) from pretraining to posttraining, with no significant difference between groups. Bioimpedance resistance decreased similarly in both groups (G2X = −1.7% vs. G3X = −3.2%). We conclude that a single set RT program with a frequency of 2 days per week may be sufficient to promote an improvement in cellular health in older women.

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João Pedro Nunes, Alex S. Ribeiro, Analiza M. Silva, Brad J. Schoenfeld, Leandro dos Santos, Paolo M. Cunha, Matheus A. Nascimento, Crisieli M. Tomeleri, Hellen C.G. Nabuco, Melissa Antunes, Letícia T. Cyrino and Edilson S. Cyrino

The aim of this study was to analyze the association between muscle quality index (MQI) and phase angle (PhA) after a program of progressive resistance training (RT) in older women. Sixty-six older women with previous RT experience (68.8 ± 4.6 years, 156.6 ± 5.3 cm, 66.0 ± 13.0 kg, and 26.7 ± 4.6 kg/m2) underwent 12 weeks of RT (3 ×/week, eight exercises, and 10–15 repetition maximum). Anthropometry, muscular strength (one-repetition maximum tests), and body composition (dual-energy X-ray absorptiometry and spectral bioimpedance) were measured pre- and posttraining. There were observed significant increases for PhA, MQI, muscular strength, muscle mass, and reactance, whereas no significant changes in body fat and resistance were found. A significant correlation was observed between the RT-induced relative changes in PhA and MQI (r = .620). We conclude that improvements in MQI induced by RT are associated with increases in PhA. Therefore, PhA may be a valid tool to track changes in MQI after 12 weeks of RT in older women.

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Alex S. Ribeiro, Fábio Luiz C. Pina, Soraya R. Dodero, Danilo R. P. Silva, Brad J. Schoenfeld, Paulo Sugihara Júnior, Rodrigo R. Fernandes, Décio S. Barbosa, Edilson S. Cyrino and Julio Tirapegui

The aim of this study was to analyze the effects of 8 weeks of conjugated linoleic acid (CLA) supplementation associated with aerobic exercise on body fat and lipid profile on obese women. We performed a randomized, double-blinded and placebo-controlled trial with 28 obese women who received 3.2 g/day of CLA or 4 g/day of olive oil (placebo group) while performing an 8-week protocol of aerobic exercise. Dietary intake (food record), body fat (dual-energy X-ray absorptiometry), and biochemical analysis (blood sample) were assessed before and after the intervention period. Independent of CLA supplementation, both groups improved (p < .05) oxygen uptake (CLA group, 13.2%; PLC group, 14.8%), trunk fat (CLA group, −1.0%; PLC group, −0.5%), leg fat (CLA group, −1.0%; PLC group, −1.6%), and total body fat (CLA group, −1.7%; PLC group, −1.3%) after the 8-week intervention. No main effect or Group × Time interaction was found for total cholesterol, triglycerides, and plasma lipoproteins (p > .05). We conclude that CLA supplementation associated with aerobic exercise has no effect on body fat reduction and lipid profile improvements over placebo in young adult obese women.