Kinesiotherapy Commons^™

Resistance Exercise Intensity Does Not Influence Neurotrophic Factors Response In Equated Volume Schemes, Leandro Lodo, Alexandre Moreira, Reury Frank P Bacurau, Carol D. Capitani, Wesley P. Barbosa, Marcelo Massa, Brad J. Schoenfeld, Marcelo S. Aoki

Publications and Research

The aim of the present study was to evaluate the effects of 2 different intensities of resistance training (RT) bouts, performed with the equated total load lifted (TLL), on the acute responses of neurotrophic factors (NFs) (brain-derived neurotrophic factor [BDNF]; and nerve growth factor [NGF]), as well as on metabolic (lactate concentration) and hormonal (salivary cortisol concentration) responses. Thirty participants (males, 22.8 ± 2.3 years old, 177 ± 6.8 cm, 75.5 ± 7.9 kg, n = 15; and females, 22.2 ± 1.7 years, 163.7 ± 6.5 cm, 57 ± 7.6 kg, n = 15) performed 2 separate acute RT bouts …

Pre-Stretching Of The Hamstrings Before Squatting Acutely Increases Biceps Femoris Thickness Without Impairing Exercise Performance, Thiago Barbosa Trindade, Leônidas Oliveira Neto, José Claudino Neto Pita, Vagner Deuel De Oliveira Tavares, Paulo Moreira Silva Dantas, Brad J. Schoenfeld, Jonato Prestes

Publications and Research

Background: Bilateral squat exercise is widely used in resistance training (RT) programs to increase lower limb strength and muscle mass, but this exercise does not result in significant hypertrophy of the hamstrings. It has been speculated that stretching between sets with a certain degree of tension results in muscle hypertrophy, while acute stretching could decrease performance during maximal contractions.

Objective: This study investigated the acute effects of hamstring stretching before bilateral squatting on muscle thickness (MT), electromyography (EMG), and total training volume (TTV) on exercise performance.

Methods: Fourteen resistance-trained young men, with ∼7.5 years of RT experience, performed the 10 …

Commentary: Can Blood Flow Restricted Exercise Cause Muscle Damage? Commentary On Blood Flow Restriction Exercise: Considerations Of Methodology, Application, And Safety, Mathias Wernbom, Brad J. Schoenfeld, Gøran Paulsen, Thomas Bjørnsen, Kristoffer T. Cumming, Per Aagaard, Brian C. Clark, Truls Raastad

Publications and Research

Low-load exercise combined with blood flow restriction (BFR) is known to induce significant gains in muscle strength and size, and this mode of training is increasingly used in both healthy and clinical populations, as documented in the recent review of Patterson et al. (2019). However, since the first training studies on BFR exercise appeared about 20 years ago, there have been some concerns about its safety, in particular with regard to the potential risk for muscle damage (Wernbom et al., 2019). In a recent editorial, Wernbom et al. (2019) briefly discussed the accumulating evidence for muscle damage and rhabdomyolysis with …

Caffeine Ingestion Enhances Repetition Velocity In Resistance Exercise: A Randomized, Crossover, Double-Blind Study Involving Control And Placebo Conditions, Jozo Grgic, Sandro Venier, Brad J. Schoenfeld, Pavle Mikulic

Publications and Research

We aimed to examine the effects of placebo and caffeine compared to a control condition on mean velocity in the bench press exercise. Twenty-five resistance-trained men participated in this randomized, crossover, double-blind study. The participants performed the bench press with loads of 50%, 75%, and 90% of one-repetition maximum (1RM), after no supplementation (i.e., control), and after ingesting caffeine (6 mg/kg), and placebo (6 mg/kg of dextrose). At 50% 1RM, there was a significant effect of caffeine on mean velocity compared to control (effect size [ES] = 0.29; p = 0.003), but not when compared to placebo (ES = 0.09; …

Do The Anatomical And Physiological Properties Of A Muscle Determine Its Adaptive Response To Different Loading Protocols?, Brad J. Schoenfeld, Andrew D. Vigotsky, Jozo Grgic, Cody Haun, Bret Contreras, Kenneth Delcastillo, Aston Francis, Gilda Cote, Andrew Alto

Publications and Research

It has been proposed that superior muscle hypertrophy may be obtained by training muscles predominant in type I fibers with lighter loads and those predominant in type II fibers with heavier loads.

Purpose: To evaluate longitudinal changes in muscle strength and hypertrophy of the soleus (a predominantly slow-twitch muscle) and gastrocnemius (muscle with a similar composition of slow and fast-twitch fibers) when subjected to light (20–30 repetition maximum) and heavy (6–10 repetition maximum) load plantarflexion exercise.

Methods: The study employed a within-subject design whereby 26 untrained young men had their lower limbs randomized to perform plantarflexion with a low-load (LIGHT) …

Mean Propulsive Velocity Is A Viable Method For Adjusting The Resistance-Training Load At Moderate Altitude, Lara Rodríguez-Zamora, Paulino Padial, Brad Jon Schoenfeld, Belén Feriche

Publications and Research

We examined the viability of using mean propulsive velocity (MPV) to adjust the load in the countermovement jump (CMJ) at moderate altitude. Twenty-four volunteers were assigned to a 4-week power-oriented resistance training (R_T) program in either normoxia (N, 690m) or intermittent hypobaric hypoxia (IH, 2,320m). The load was adjusted to maintain execution velocity of CMJ at 1m·s⁻¹ of MPV. Relative peak power output (P_rel), and percentage of velocity loss throughout the sets (VL) were determined for each session. The internal load was measured by the rating of perceived exertion (RPE). The absolute load lifted was …

Calculating Set-Volume For The Limb Muscles With The Performance Of Multi-Joint Exercises: Implications For Resistance Training Prescription, Brad J. Schoenfeld, Jozo Grgic, Cody Haun, Takahiro Itagaki, Eric R. Helms

Publications and Research

Resistance training volume, determined by the number of sets performed (set-volume) is considered one of the key variables in promoting muscle hypertrophy. To better guide resistance exercise prescription for weekly per-muscle training volume, the purpose of this paper is to provide evidence-based considerations for set-volume ratios between multi-joint (MJ) and single-joint (SJ) exercises so that practitioners can better manage prescription of training volume in program design. We analyzed this topic from three primary areas of focus: (1) biomechanical and physiological factors; (2) acute research; and (3) longitudinal research. From a biomechanical and physiological standpoint, when considering force production of different …

Effects Of Different Dietary Energy Intake Following Resistance Training On Muscle Mass And Body Fat In Bodybuilders: A Pilot Study, Alex S. Ribeiro, João Pedro Nunes, Brad J. Schoenfeld, Andreo F. Aguiar, Edilson S. Cyrino

Publications and Research

The purpose of this study was to determine the effects of different amounts of energy intake in combination with progressive resistance training on muscle mass and body fat in bodybuilders. Eleven male bodybuilders (26.8 ± 2.3 years, 90.1 ± 9.7 kg, and 176.9 ± 7.1 cm) were randomly assigned into one of two groups: a group that ingested higher amounts of energy (G1, 67.5 ± 1.7 kcal/kg/d, n = 6), and a group that ingested moderate amounts of energy (G2, 50.1 ± 0.51 kcal/kg/d, n = 5). Both groups performed resistance training 6 days per week over a 4-week study …