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ABSTRACT: Nunes, JP, Blazevich, AJ, Schoenfeld, BJ, Kassiano, W, Costa, BDV, Ribeiro, AS, Nakamura, M, Nosaka, K, and Cyrino, ES. Determining changes in muscle size and architecture after exercise training: One site does not fit all. J Strength Cond Res 38(4): 787-790, 2024-Different methods can be used to assess muscle hypertrophy, but the effects of training on regional changes in muscle size can be detected only using direct muscle measurements such as muscle thickness, cross-sectional area, or volume. Importantly, muscle size increases vary across regions within and between muscles after resistance training programs (i.e., heterogeneous, or nonuniform, muscle hypertrophy). Muscle architectural changes, including fascicle length and pennation angle, after resistance and stretch training programs are also region-specific. In this paper, we show that the literature indicates that a single-site measure of muscle shape does not properly capture the effects achieved after exercise training interventions and that conclusions concerning the magnitude of muscle adaptations can vary substantially depending on the muscle site to be examined. Thus, we propose that measurements of muscle size and architecture should be completed at multiple sites across regions between the agonist muscles within a muscle group and along the length of the muscles to provide an adequate picture of training effects.

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Cell swelling caused by resistance training is proposed to provide an anabolic stimulus for muscle growth and it is believed that these effects are heightened with the use of low loads. The purpose of this study was to compare the acute effects of two volume-equated resistance training (RT) protocols, low-load (LL) versus high-load (HL), on elbow flexor muscles thickness, arm circumference, and blood lactate concentration in well-trained individuals. Eight resistance-trained males performed the following two RT protocols involving unilateral elbow flexion of the dominant arm: i) LL, four sets with 50% 1 repetition-maximum [1 RM] and ii) HL, ten sets with 85% 1 RM until failure, and equated volume. Pre- and post-session measurements included muscle thickness of the elbow flexors (biceps brachii and brachialis), upper arm circumference, and blood lactate concentration. Significant pre- to post-session increases were found in both protocols for muscle thickness (F (1, 28) = 11.74, p = 0.0019), and blood lactate (F (1, 28) = 35.55, p < 0.0001); no statistically significant differences were observed between conditions, however, the magnitude of increases favored LL. Significant between-condition differences favoring LL were observed for total repetitions (p = 0.007), time under tension (p = 0.007), and training density (p = 0.007). These results suggest that LL training promotes superior post-session increases in muscle thickness, indicating that RT protocols with longer times under tension and densities are beneficial when the goal is to promote acute cell swelling.

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This study's purpose was to compare the effects of different carbohydrate (CHO) intakes on body composition and muscular strength following eight weeks of resistance training (RT) in pre-conditioned men. In addition, we explored the individual responses to different CHO intakes. Twenty-nine young men volunteered to participate in this study. The participants were divided into two groups according to their relative CHO intake: lower (L-CHO; n = 14) and higher (H-CHO; n = 15). Participants performed a RT program four days a week for eight weeks. The lean soft tissue (LST) and fat mass were determined by dual-energy X-ray absorptiometry. Muscular strength was determined by a one-repetition maximum (1RM) test in the bench press, squat, and arm curl exercises. Both groups increased LST (P < 0.05) with no statistical differences between conditions (L-CHO = +0.8% vs. H-CHO = +3.5%). Neither group demonstrated changes in fat mass. Both groups increased 1RM (P < 0.05) in the bench press (L-CHO = +3.6% vs. H-CHO = +5.8%) and squat (L-CHO = +7.5% vs. H-CHO = +9.4%); however, only H-CHO significantly increased arm curl 1RM (P < 0.05) at post-training (L-CHO = +3.0% vs. H-CHO = +6.6%). Responsiveness was greater in H-CHO vs. L-CHO for LST and arm curl 1RM. In conclusion, lower and higher CHO intakes promote similar increase in LST and muscular strength; however, a greater intake may improve the responsiveness to gains in lean mass and arm curl strength in pre-conditioned men.

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OBJECTIVE: The effects of ROM manipulation on muscle strength and hypertrophy response remain understudied in long-term interventions. Thus, we compared the changes in strength and regional muscle hypertrophy after training in protocols with different ranges of motion (ROM) in the seated dumbbell preacher curl exercise using a within-participant experimental design. DESIGN AND METHODS: Nineteen young women had one arm randomly assigned to train in the initial ROM (INITIALROM: 0°-68°; 0° = extended elbow) while the contralateral arm trained in the final ROM (FINALROM: 68°-135°), three times per week over an eight-week study period. Pre- and post-training assessments included one repetition maximum (1RM) testing in the full ROM (0°-135°), and measurement of biceps brachii cross-sectional area (CSA) at 50% and 70% of humerus length. Paired t-tests were used to compare regional CSA changes between groups, the sum of CSA changes at 50% and 70% (CSAsummed), and the strength response between the training protocols. RESULTS: The INITIALROM protocol displayed a greater CSA increase than FINALROM protocol at 70% of biceps length (p = 0.001). Alternatively, we observed similar increases between the protocols for CSA at 50% (p = 0.311) and for CSAsummed (p = 0.111). Moreover, the INITIALROM protocol displayed a greater 1RM increase than FINALROM (p < 0.001). CONCLUSIONS: We conclude that training in the initial angles of elbow flexion exercise promotes greater distal hypertrophy of the biceps brachii muscle in untrained young women. Moreover, the INITIALROM condition promotes a greater dynamic strength increase when tested at a full ROM compared to the FINALROM.

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ABSTRACT: Kassiano, W, Costa, B, Nunes, JP, Ribeiro, AS, Schoenfeld, BJ, and Cyrino, ES. Which ROMs lead to Rome? a systematic review of the effects of range of motion on muscle hypertrophy. J Strength Cond Res 37(5): 1135-1144, 2022-Resistance exercise range of motion (ROM) influences muscular adaptations. However, there are no consistent practical guidelines about the optimal ROM for maximizing muscle hypertrophy. The objective of this article was to systematically review the literature for studies that compared the effects of full ROM (fROM) and partial ROM (pROM) on muscle hypertrophy. PubMed/MEDLINE, Scopus, and Web of Science databases were searched to identify articles from the earliest record up to and including April 2022. We calculated the effect size (ES) scores of the variables of interest. Eleven studies were included in the review. Full ROM and pROM performed in the initial part of the ROM elicited greater muscle hypertrophy of the rectus femoris, vastus lateralis, biceps brachii, and brachialis distal sites (between-groups ES: 0.20-0.90) than pROM performed in the final part of the ROM. fROM elicited greater muscle growth on the gluteus maximus and adductors than pROM in the final part of the ROM (between-groups ES: 0.24-0.25). Initial pROM produced more favorable proximal rectus femoris hypertrophy than fROM (between-groups ES: 0.35-0.38). pROM in the middle part of the ROM elicited greater triceps brachii hypertrophy than fROM (between-group ES: 1.21). In conclusion, evidence suggests that when training at a longer muscle length-through either pROM or fROM-some muscles, such as quadriceps femoris, biceps brachii, and triceps brachii, tend to experience optimal growth. Thus, the use pROM in the initial part of the excursion in combination with fROM training should be considered when prescribing hypertrophy-oriented resistance training programs.

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BACKGROUND: this observational and cross-sectional study aimed to describe training, pharmacological ergogenic aids, dehydration, and nutrition strategies during a peak week in competitive bodybuilders and monitor changes that occurred across this period. METHODS: Ten amateur bodybuilders were followed during a peak week phase and one day post-contest. Training, diet, dehydration protocol, anabolic steroid use, and nonsteroidal agents were recorded, prescribed, and supervised by the same coach in charge. Body composition, resting metabolic rate, and circumferences were assessed by the research team. RESULTS: Overall, during the peak week phase, the use of anabolic steroids, diuretics, and other pharmacological aids was high among athletes, and the dose and frequency were similar between competitors. Despite the use of supraphysiological doses of drugs, bodybuilders displayed a statistical reduction of lean mass markers, resting metabolic rate, and fat mass markers, possibly influenced by the performance of high volumes of aerobic exercise combined with dietary energy restriction. CONCLUSIONS: The main findings of this study display that the coach in charge of Brazilian bodybuilders applied the same anabolic steroid, diuretic, and other pharmacological protocols for all competitors. Moreover, the protocols employed by bodybuilders did not fully attenuate the loss of lean mass during the peak week period.

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ABSTRACT: Kassiano, W, Nunes, JP, Costa, B, Ribeiro, AS, Schoenfeld, BJ, and Cyrino, ES. Does varying resistance exercises promote superior muscle hypertrophy and strength gains? A systematic review. J Strength Cond Res 36(6): 1753-1762, 2022-Fitness professionals routinely employ a variety of resistance training exercises in program design as a strategy to enhance muscular adaptations. However, it remains uncertain whether such an approach offers advantages over a fixed-exercise selection. The objective of this review was to review the effects of exercise variation on muscle hypertrophy and strength. A search of the literature was conducted using PubMed/MEDLINE, Scopus, and Web of Science databases. Eight studies were identified as meeting inclusion criteria. The combined total sample of the studies was N = 241, comprising all young men. The methodological quality of included studies was considered "good" and "excellent" based on the Physiotherapy Evidence Database Scale. The available studies indicate that varying exercise selection can influence muscle hypertrophy and strength gains. Some degree of systematic variation seems to enhance regional hypertrophic adaptations and maximize dynamic strength, whereas excessive, random variation may compromise muscular gains. We conclude that exercise variation should be approached systematically with a focus on applied anatomical and biomechanical constructs; on the contrary, employing different exercises that provide a redundant stimulus, as well as excessive rotation of different exercises (i.e., high frequency of change), may actually hinder muscular adaptations.

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The purpose of this study was to evaluate the effects of altering the duration of the eccentric phase in isotonic contractions on muscle hypertrophy and strength of the quadriceps femoris. Ten healthy young adults (8 men and 2 women: Height: 173.3 ± 9.6 cm: Body mass: 69.84 ± 10.88 kg; Body fat: 19.47 ± 8.42%; Age: 25.3 ± 4.8 years) performed unilateral isotonic knee extension exercise, whereby each leg was randomly allocated to perform the eccentric phase of movement with a duration of either 2 seconds (G2S) or 4 seconds (G4S). Both conditions carried out the concentric phase of each repetition at a 1 second duration with no rest in the transition phases. Each condition performed 5 sets using 70% of 1 repetition maximum until muscle failure with 3 minutes of rest between sets for 8 weeks. The change in muscle strength was assessed by 1RM knee extension and muscle thickness was assessed by A-mode ultrasound. For each outcome variable, linear mixed-effects models were fit using restricted maximum likelihood. Hedges' g effect sizes were calculated to provide insights into the magnitude of effects. Results showed all muscles increased in size over time; mean effects were similar in all muscles except for the vastus medialis, which favored the G4S condition. Conversely, only a trivial and highly variable effect was observed between interventions for strength gain. Our results suggest different eccentric durations produce similar increases in hypertrophy of the vastus lateralis and rectus femoris; however, the vastus medialis showed greater growth from the slower eccentric duration. Eccentric duration did not differentially affect strength-related adaptations.

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ABSTRACT: Cunha, PM, Ribeiro, AS, Padilha, C, Nunes, JP, Schoenfeld, BJ, Cyrino, LT, Tomeleri, CM, Nascimento, MA, Antunes, M, Fernandes, RR, Barbosa, DS, Venturini, D, Burini, RC, Sardinha, LB, and Cyrino, ES. Improvement of oxidative stress in older women is dependent on resistance training volume: Active aging longitudinal study. J Strength Cond Res 36(4): 1141-1146, 2022-The purpose of the present study was to investigate the effects of resistance training (RT) performed with a higher versus lower training volume on oxidative stress (OS) biomarkers in older women. Thirty-eight older women (≥60 years) were randomly assigned to 1 of 2 groups: a group that performed 1 set per exercise (low volume [LV], n = 18) or 3 sets per exercise (high volume [HV], n = 20). The whole-body RT consisted of a 12-week RT program involving 8 exercises performed with sets of 10-15 repetitions maximum, 3 days per week. Advanced oxidation protein products (AOPP), total radical-trapping antioxidant parameter (TRAP), and ferrous oxidation-xylenol orange (FOX) were used as OS biomarkers. The composite Z-score of the percentage changes from pre- to posttraining of OS biomarkers according to groups was calculated. A significant main effect of time (p < 0.05) was found for AOPP (LV = -7.3% vs. HV = -12.2%) and TRAP (LV = +1.5% vs. HV = +15.5%) concentrations, without a statistical difference between the groups (p > 0.05). A significant group vs. time interaction (p < 0.001) was revealed for FOX (LV = +6.4% vs. HV = -8.9%). The overall analysis indicated higher positive changes for HV than LV (composed Z-score: HV = 0.41 ± 1.22 vs. LV = -0.37 ± 1.03; p < 0.05). Our results suggest that a greater volume of RT seems to promote superior improvements on OS biomarkers in older women.

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The present study analyzed the effects from day-before to day-of bodybuilding competition on intracellular water (ICW), extracellular water (ECW), total body water (TBW), and bioimpedance analysis (BIA) parameters (resistance, R; reactance, Xc; and derived scores) in bodybuilding athletes. We assessed anthropometry and BIA (foot-to-hand; tetrapolar; 50 kHz) in 11 male bodybuilders (29 ± 4 year-old; 81 ± 8 kg; 172 ± 7 cm; 27 ± 2 kg/m2) both on the pre-competition day and on the contest day. Results revealed significant increases in ICW (31.6 ± 2.9 to 33.1 ± 2.8 L), with concomitant decreases in ECW (19.8 ± 1.8 to 17.2 ± 1.4 L) and TBW (51.4 ± 4.6 to 50.3 ± 4.2 L) from the day-before competition to contest day, which resulted in relatively large increases in the ICW/ECW ratio (1.60 ± 0.03 to 1.92 ± 0.01 L). Moreover, significant increases in R (391 ± 34 to 413 ± 33 ohm), Xc (64 ± 7 to 70 ± 6 ohm), and phase angle (9.3 ± 0.6 to 9.6 ± 0.7 degree) were observed between time periods. The phase angle scores reported on show-day of 9.6 and 11.2 appear to be the highest group mean and individual values observed in the literature to date. In conclusion, the strategies carried out on the final day of peak-week bodybuilding preparation lead to changes in BIA parameters and body water, with fluids shifting from the extra- to the intracellular compartment.

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PURPOSE: Resistance training (RT) combined with appropriate dietary intake can promote a concomitant increase in skeletal muscle mass (SMM) and reduction in fat mass, a condition termed body recomposition. This study's primary purpose was to explore the effects of protein ingestion on body recomposition after 24 wk of RT in older women. METHODS: Data from 130 untrained older women (68.7 ± 5.6 yr, 66.5 ± 11.5 kg, 155.5 ± 6.0 cm, and 27.4 ± 4.0 kg·m-2) across six studies were retrospectively analyzed. The participants were divided into tertiles according to their customary protein intake (g·kg-1·d-1): lower (LP; n = 45), moderate (MP; n = 42), and higher (HP; n = 43) protein intake. Participants performed a whole-body RT program carried out over 24 wk (eight exercises, three sets, 8-15 repetitions, three sessions a week). SMM and fat mass were determined by dual-energy x-ray absorptiometry. RESULTS: All groups increased SMM from baseline (P < 0.05), with the HP and MP groups showing greater increases than the LP group (LP, 2.3%; MP, 5.4%; and HP, 5.1%; P < 0.05). Reductions in fat mass were similar for all three groups (LP, 1.7%; MP, 3.7%; and HP, 3.1%; P > 0.05). The composite z-score of the percentage changes from pretraining to posttraining indicated greater positive body recomposition values for HP and MP compared with LP (P < 0.05). CONCLUSIONS: Results suggest that protein intake is a moderating variable for body recomposition in older women undergoing RT, with a low protein intake having a less favorable effect on body recomposition.

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The purpose of this paper was to conduct a systematic review and meta-analysis of studies that compared muscle hypertrophy and strength gains between resistance training protocols employing very low (VLL < 30% of 1-repetition maximum (RM) or >35RM), low (LL30%-59% of 1RM, or 16-35RM), moderate (ML60%-79% of 1RM, or 8-15RM), and high (HL ≥ 80% of 1RM, or ≤7RM) loads with matched volume loads (sets × repetitions × weight). A pooled analysis of the standardized mean difference for 1RM strength outcomes across the studies showed a benefit favoring HL vs. LL and vs. ML and favoring ML vs. LL. The LL and VLL results showed little difference. A pooled analysis of the standardized mean difference for hypertrophy outcomes across all studies showed no differences between training loads. Our findings indicate that when the volume load is equal between conditions, the highest loads induce superior dynamic strength gains. Alternatively, hypertrophic adaptations were similar irrespective of the load magnitude. Novelty: Training with higher loads elicits greater gains in 1RM muscle strength when compared to lower loads, even when the volume load is equal between conditions. Muscle hypertrophy is similar irrespective of the magnitude of the load, even when the volume load is equal between conditions.

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The study compared changes in strength and regional muscle hypertrophy between different ranges of motion (ROM) in the knee extension exercise. Forty-five untrained women were randomized to either a control group or to perform the exercise in one of the following 4 groups (0°=extended knee): Full ROM (FULLROM: 100°-30° of knee flexion); Initial Partial ROM (INITIALROM: 100°-65°); Final Partial ROM (FINALROM: 65°-30°); Varied ROM (VARROM: daily alternation between the ROM of INITIALROM and FINALROM). Pre- and post-training assessments included one repetition maximum (1RM) testing in the ROM corresponding to the initial, final and full ROM, and measurement of cross-sectional areas of the rectus femoris and vastus lateralis muscles at 40%, 50%, 60% and 70% of femur length in regard to regional muscle hypertrophy. Results showed that the INITIALROM group presented a greater relative increase than all groups at 70%, and at 50% and 60% the increases were greater than FINALROM, FULLROM, and non-training control (CON) groups. Moreover, FINALROM group presented similar changes compared to the CON group at 60% and 70%. In regard to 1RM, FINALROM and INITIALROM groups presented greater relative increases at the ROM trained, and no group showed greater increases than VARROM or INITIALROM, regardless the ROM tested. In conclusion, partial ROM training in the initial phase of the knee extension exercise promoted greater relative hypertrophy in certain muscle regions than training in other ROM configurations, and no group promoted a greater 1RM increase than VARROM group, which showed similar 1RM increases in the different ROMs tested.

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ABSTRACT: Lasevicius, T, Schoenfeld, BJ, Silva-Batista, C, Barros, TdS, Aihara, AY, Brendon, H, Longo, AR, Tricoli, V, Peres, BdA, and Teixeira, EL. Muscle failure promotes greater muscle hypertrophy in low-load but not in high-load resistance training. J Strength Cond Res 36(2): 346-351, 2022-The purpose of this study was to investigate the effects of an 8-week resistance training program at low and high loads performed with and without achieving muscle failure on muscle strength and hypertrophy. Twenty-five untrained men participated in the 8-week study. Each lower limb was allocated to 1 of 4 unilateral knee extension protocols: repetitions to failure with low load (LL-RF; ∼34.4 repetitions); repetitions to failure with high load (HL-RF; ∼12.4 repetitions); repetitions not to failure with low load (LL-RNF; ∼19.6 repetitions); and repetitions not to failure with high load (HL-RNF; ∼6.7 repetitions). All conditions performed 3 sets with total training volume equated between conditions. The HL-RF and HL-RNF protocols used a load corresponding to 80% 1 repetition maximum (RM), while LL-RF and LL-RNF trained at 30% 1RM. Muscle strength (1RM) and quadriceps cross-sectional area (CSA) were assessed before and after intervention. Results showed that 1RM changes were significantly higher for HL-RF (33.8%, effect size [ES]: 1.24) and HL-RNF (33.4%, ES: 1.25) in the post-test when compared with the LL-RF and LL-RNF protocols (17.7%, ES: 0.82 and 15.8%, ES: 0.89, respectively). Quadriceps CSA increased significantly for HL-RF (8.1%, ES: 0.57), HL-RNF (7.7%, ES: 0.60), and LL-RF (7.8%, ES: 0.45), whereas no significant changes were observed in the LL-RNF (2.8%, ES: 0.15). We conclude that when training with low loads, training with a high level of effort seems to have greater importance than total training volume in the accretion of muscle mass, whereas for high load training, muscle failure does not promote any additional benefits. Consistent with previous research, muscle strength gains are superior when using heavier loads.

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ABSTRACT: Ribeiro, AS, Picoloto, A, Nunes, JP, Bezerra, ES, Schoenfeld, BJ, and Cyrino, ES. Effects of different resistance training loads on the muscle quality index in older women. J Strength Cond Res 36(5): 1445-1449, 2022-The purpose of this study was to investigate the effects of resistance training (RT) performed using low vs. moderate loads on muscular strength, muscle mass, and muscle quality index (MQI) in older women. Twenty-seven older women (71.5 ± 5 years, 65.2 ± 11 kg, 154.2 ± 5 cm, and 27.4 ± 4 kg·m-2) were randomized into 2 groups: one that performed RT with a low load (LOW, n = 13) and another that performed RT with a moderate load (MOD, n = 14). An 8-week RT program was performed 3 d·wk-1. Outcomes included 1-repetition maximum (1RM) tests and assessment of body composition by dual-energy X-ray absorptiometry. The LOW load consisted of a relative load at 15RM, whereas the MOD load consisted of a relative load at 10RM. Both groups presented significant changes from pre-training to post-training for chest press 1RM (LOW = 10.3%, and MOD = 11.1%), knee extension 1RM (LOW = 14.4%, and MOD = 16.6%), preacher curl 1RM (LOW = 12.4%, and MOD = 12.0%), fat-free mass (LOW = 2.1%, and MOD = 1.9%), body fat (LOW = -3.2%, and MOD = -2.7%), and MQI (LOW = 10.6%, and MOD = 11.3%). Results were similar (p > 0.05) between groups. These findings suggest that LOW and MOD loads are equally effective for promoting improvements in muscular strength and muscle growth as well as the MQI in older women.

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ABSTRACT: Zandona, BA, Ramos, RA, de Oliveira, CdS, McAnulty, SR, Ferreira, LHB, Smolarek, AC, Enes, AAN, Urbinati, KMdSS, Aragon, AA, Schoenfeld, BJ, and de Souza Junior, TP. Reduced Dose of Beta-Alanine Is Sufficient to Maintain Performance in Repeated Sprints. J Strength Cond Res 36(6): 1636-1642, 2022-Beta-alanine (BA) supplementation has been shown to be effective in improving physical performance by increasing carnosine concentration. However, it is still necessary to know the effect of a maintenance dose on performance. Thus, this study aimed to investigate the effects of a maintenance dose of BA supplementation on performance. Forty-four anaerobically trained men with 23.9 ± 3.8 years of age, 176.0 ± 0.05 cm height, 81.2 ± 7.5 kg body mass, and 15.5 ± 2.9% of body fat performed a cycle ergometer test consisting of 4 sprints of 30 s with 4 minutes of active recovery. The study comprised 3 phases: (a) presupplementation, (b) supplementation with 6.4 g·d-1 BA or placebo, and (c) postsupplementation with a maintenance dose of 1.2 g·d-1 of BA or interruption of supplementation. Data were analyzed using generalized estimated equations with a priori 0.05 level of significance. The placebo group and interruption group presented a lower power (7.28 ± 0.66 and 7.71 ± 0.42 W·kg-1 vs. 8.04 ± 0.84 and 9.25 ± 1.18 W·kg-1, respectively; p < 0.05) during the third sprint in postsupplementation, whereas the maintenance group maintained the required power (7.47 ± 1.03 vs. 8.74 ± 1.07 W·kg-1; p > 0.05). The placebo group also presented higher percentage of fatigue (44.5% ± 12.3 and 44.8% ± 7.7 vs. 37.6 ± 7.2%; p = 0.021) and higher subjective perception of exertion (8.92 ± 0.90 vs. 8.00 ± 1.60; p = 0.028). Therefore, the maintenance dose of 1.2 g·d-1 BA was effective in maintaining performance, whereas a reduction in performance was observed after supplementation interruption.

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We compared the effects of different resistance training (RT) volume reduction strategies on muscular strength and lean soft-tissue (LST) in older women. Fifty-seven physically independent women (>60 years) performed a 20-week pre-conditioning phase of a standardized whole-body RT program (eight exercises, three sets, 8-12 repetitions, three sessions a week), and were then randomly assigned to one of the following conditions: reduced volume for a single set (RV1, n=20) or two sets (RV2, n=19), or maintained volume of three sets (MV, n=18) for 8 weeks (specific training phase). Muscular strength in the chest press, leg extension, and preacher curl exercises was determined by one-repetition maximum tests. A dual-energy X-ray absorptiometry device was used to estimate LST. An increase in muscular strength (16.3-32.1%) and LST (3.2-7.9%) was observed after the pre-conditioning phase. There was an increase in chest press for all groups (9.4-16.7%) after the specific training phase. In contrast, only MV increased significantly in the leg extension (4.4%). No between-group differences were revealed for LST in the specific training phase. Our results suggest that reduced RT volume from three to one set per exercise for 8 weeks seems sufficient to retain neuromuscular adaptations in older women.

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Whole egg may have potential benefits for enhancing muscle mass, independent of its protein content. The yolk comprises ∼40% of the total protein in an egg, as well as containing several nonprotein nutrients that could possess anabolic properties (e.g., microRNAs, vitamins, minerals, lipids, phosphatidic acid and other phospholipids). Therefore, the purpose of this narrative review is to discuss the current evidence as to the possible effects of egg yolk compounds on skeletal muscle accretion beyond those of egg whites alone. The intake of whole egg seems to promote greater myofibrillar protein synthesis than egg white intake in young men. However, limited evidence shows no difference in muscle hypertrophy when comparing the consumption of whole egg versus an isonitrogenous quantity of egg white in young men performing resistance training. Although egg yolk intake seems to promote additional acute increases on myofibrillar protein synthesis, it does not seem to further enhance muscle mass when compared to egg whites when consumed as part of a high-protein dietary patterns, at least in young men. This conclusion is based on very limited evidence and more studies are needed to evaluate the effects of egg yolk (or whole eggs) intake on muscle mass not only in young men, but also in other populations such as women, older adults, and individuals with muscle wasting diseases.

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This paper aimed to compare the effect of drop-set (DS) and rest-pause (RP) systems versus traditional resistance training (TRT) with equalized total training volume on maximum dynamic strength (1RM) and thigh muscle thickness (MT). Twenty-eight resistance-trained males were randomly assigned to either RP (n = 10), DS (n = 9) or TRT (n = 9) protocols performed twice a week for 8 weeks. 1RM and MT of the proximal, middle and distal portions of the lateral thigh were assessed at baseline and post-intervention. A significant time × group interaction was observed for 1RM (P = 0.001) in the barbell back squat after 8-weeks. Post hoc comparisons revealed that RP promoted higher 1RM than TRT (P = 0.001); no statistical differences in strength were observed between the other conditions. A significant main effect of time was revealed for MT at the proximal (P = 0.0001) and middle (P = 0.0001) aspects of the lateral thigh for all training groups; however, the distal portion did not show a time effect (P = 0.190). There were no between-group interactions for MT. Our findings suggest that RP promotes slightly superior strength-related improvements compared with TRT, but hypertrophic adaptations are similar between conditions. Novelty: Rest-pause elicited a slightly superior benefit for strength adaptations compared with traditional resistance training. Resistance training systems do not promote superior hypertrophic adaptations when total training volume is equalized. Muscle thickness in distal portion of thigh is similar to baseline. Although modest, effect sizes tended to favor rest-pause.

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