Medicine and Health Sciences Commons^™

International Society Of Sports Nutrition Position Stand: Caffeine And Exercise Performance, Nanci S. Guest, Trisha A. Vandusseldorp, Michael T. Nelson, Jozo Grgic, Brad J. Schoenfeld, Nathaniel D.M. Jenkins, Shawn M. Arent, Jose Antonio, Jeffrey R. Stout, Eric T. Trexler, Abbie E. Smith-Ryan, Erica R. Goldstein, Douglas S. Kalman, Bill I. Campbell

Publications and Research

Following critical evaluation of the available literature to date, The International Society of Sports Nutrition (ISSN) position regarding caffeine intake is as follows: 1. Supplementation with caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions. 2. Aerobic endurance appears to be the form of exercise with the most consistent moderate-to-large benefits from caffeine use, …

Cyp1a2 Genotype And Acute Effects Of Caffeine On Resistance Exercise, Jumping, And Sprinting Performance, Jozo Grgic, Craig Pickering, David Bishop, Brad J. Schoenfeld, Pavle Mikulic, Zeljko Pedisic

Publications and Research

Background: It has been suggested that polymorphisms within CYP1A2 impact inter-individual variation in the response to caffeine. The purpose of this study was to explore the acute effects of caffeine on resistance exercise, jumping, and sprinting performance in a sample of resistance-trained men, and to examine the influence of genetic variation of CYP1A2 (rs762551) on the individual variation in responses to caffeine ingestion.

Methods: Twenty-two men were included as participants (AA homozygotes n = 13; C-allele carriers n = 9) and were tested after the ingestion of caffeine (3 mg/kg of body mass) and a placebo. Exercise performance was assessed …

Effects Of A Ketogenic Diet On Body Compostion And Strength In Trained Women, Salvador Vargas-Molina, Jorge L. Petro, Ramón Romance, Richard B. Kreider, Brad J. Schoenfeld, Diego A. Bonilla, Javier Benítez-Porres

Publications and Research

Background: The effect of ketogenic diets (KD) on body composition in different populations has been investigated. More recently, some have recommended that athletes adhere to ketogenic diets in order to optimize changes in body composition during training. However, there is less evidence related to trained women. We aimed to evaluate the effect of a KD on body composition and strength in trained women following an eight-week resistance training (RT) program.

Methods: Twenty-one strength-trained women (27.6 ± 4.0 years; 162.1 ± 6.6 cm; 62.3 ± 7.8 kg; 23.7 ± 2.9 kg·m− 2) were randomly assigned to either a non-KD group (n …

Adora2a C Allele Carriers Exhibit Ergogenic Responses To Caffeine Supplementation, Jozo Grgic, Craig Pickering, David J. Bishop, Juan Del Coso, Brad J. Schoenfeld, Grant M. Tinsley, Zeljko Pedisic

Publications and Research

Caffeine's ergogenic effects on exercise performance are generally explained by its ability to bind to adenosine receptors. ADORA2A is the gene that encodes A2A subtypes of adenosine receptors. It has been suggested that ADORA2A gene polymorphisms may be responsible for the inter-individual variations in the effects of caffeine on exercise performance. In the only study that explored the influence of variation in ADORA2A—in this case, a common polymorphism (rs5751876)—on the ergogenic effects of caffeine on exercise performance, C allele carriers were identified as “non-responders” to caffeine. To explore if C allele carriers are true “non-responders” to the ergogenic effects of …

The Effects Of Caffeine Ingestion On Measures Of Rowing Performance: A Systematic Review And Meta-Analysis, Jozo Grgic, Francisco Javier Diaz-Lara, Juan Del Coso, Michael J. Duncan, Jason Tallis, Craig Pickering, Brad J. Schoenfeld, Pavle Mikulic

Publications and Research

The purpose of this paper was to conduct a systematic review and a meta-analysis of studies examining the acute effects of caffeine ingestion on measures of rowing performance. Crossover and placebo-controlled experiments that investigated the effects of caffeine ingestion on measures of rowing performance were included. The PEDro checklist was used to assess the methodological quality of the included studies. Seven studies of good and excellent methodological quality were included. None of the included studies examined on-water rowing. The majority of studies that were included in the meta-analysis used a 2000m rowing distance with only one using 1000m distance. Results …

Comparison Of Blood Lactate And Perceived Exertion Responses In Two Matched Time-Under- Tension Protocols, Salvador Vargas-Molina, Fernando Martín-Rivera, Diego A. Bonilla, Jorge L. Petro, Leandro Carbone, Ramón Romance, Manuel Dediego, Brad J. Schoenfeld, Javier Benítez-Porres

Publications and Research

Purpose: The aim of this study was to compare the concentration of blood lactate [bLa-] and the subjective perception of exertion of trained men in a moderate repetition protocol (MRP) versus a high repetition protocol (HRP) equated for time under tension.

Methods: A sample of 40 healthy young men (aged, 23.2 ± 4.0 years; height, 177.3 ± 7.0 cm; BMI, 24.3 ± 2.2) performed two sessions of 8 sets of bicep curls with a one-week recovery interval between the trials. In the HRP protocol, 20 repetitions were performed with a cadence of 2 seconds of eccentric and 1 …

Resistance Training Volume Enhances Muscle Hypertrophy But Not Strength In Trained Men, Brad J. Schoenfeld, Bret Contreras, James Krieger, Jozo Grgic, Kenneth Delcastillo, Ramon Belliard, Andrew Alto

Publications and Research

Purpose: The purpose of this study was to evaluate muscular adaptations between low-, moderate-, and high-volume resistance training protocols in resistance-trained men.

Methods: Thirty-four healthy resistance-trained men were randomly assigned to one of three experimental groups: a low-volume group performing one set per exercise per training session (n = 11), a moderate-volume group performing three sets per exercise per training session (n = 12), or a high-volume group performing five sets per exercise per training session (n = 11). Training for all routines consisted of three weekly sessions performed on nonconsecutive days for 8 wk. Muscular strength was evaluated with …

Resistance Training-Induced Gains In Muscle Strength, Body Composition, And Functional Capacity Are Attenuated In Elderly Women With Sarcopenic Obesity, Alessandro De Oliveira Silva, Maurílio Tiradentes Dutra, Wilson Max Almeida Monteiro De Moraes, Silvana Schwerz Funghetto, Darlan Lopes De Farias, Paulo Henrique Fernandes Dos Santos, Denis Cesar Leite Vieira, Dahan Da Cunha Nascimento, Vânia Silva Macedo Orsano, Brad J. Schoenfeld, Jonato Prestes

Publications and Research

Objectives: The purpose of this study was to compare the effects of resistance training (RT) on body composition, muscle strength, and functional capacity in elderly women with and without sarcopenic obesity (SO).

Methods: A total of 49 women (aged $60 years) were divided in two groups: without SO (non-SO, n=41) and with SO (n=8). Both groups performed a periodized RT program consisting of two weekly sessions for 16 weeks. All measures were assessed at baseline and postintervention, including anthropometry and body composition (dual-energy X-ray absorptiometry), muscle strength (one repetition maximum) for chest press and 45° leg press, and functional capacity …

How Much Protein Can The Body Use In A Single Meal For Muscle-Building? Implications For Daily Protein Distribution, Brad Jon Schoenfeld, Alan Albert Aragon

Publications and Research

Controversy exists about the maximum amount of protein that can be utilized for lean tissue-building purposes in a single meal for those involved in regimented resistance training. It has been proposed that muscle protein synthesis is maximized in young adults with an intake of ~ 20–25 g of a high-quality protein; anything above this amount is believed to be oxidized for energy or transaminated to form urea and other organic acids. However, these findings are specific to the provision of fast-digesting proteins without the addition of other macronutrients. Consumption of slower-acting protein sources, particularly when consumed in combination with other …

International Society Of Sports Nutrition Position Stand: Nutrient Timing, Chad M. Kerksick, Shawn Arent, Brad J. Schoenfeld, Jeffrey R. Stout, Bill Campbell, Colin D. Wilborn, Lem Taylor, Doug Kalman, Abbie E. Smith-Ryan, Richard B. Krieder, Darryn Willoughby, Paul J. Arciero, Trisha A. Vandusseldorp, Michael J. Ormsbee, Robert Wildman, Mike Greenwood, Tim N. Ziegenfuss, Alan A. Aragon, Jose Antonio

Publications and Research

Position statement: The International Society of Sports Nutrition (ISSN) provides an objective and critical review regarding the timing of macronutrients in reference to healthy, exercising adults and in particular highly trained individuals on exercise performance and body composition. The following points summarize the position of the ISSN: 1. Nutrient timing incorporates the use ofmethodical planning and eating ofwhole foods, fortified foods and dietary supplements. The timing of energy intake and the ratio of certain ingestedmacronutrientsmay enhance recovery and tissue repair, augmentmuscle protein synthesis (MPS), and improvemood states following high-volume or intense exercise. 2. Endogenous glycogen stores are maximized by following …

The Effect Of Different Resistance Training Load Schemes On Strength And Body Composition In Trained Men, Charles Ricardo Lopes, Marcelo Saldanha Aoki, Alex Harley Crisp, Renê Scarpari De Mattos, Miguel Alves Lins, Gustavo Ribeiro Da Mota, Brad Jon Schoenfeld, Paulo Henrique Marchetti

Publications and Research

The purpose of this study was to evaluate the impact of moderate-load (10 RM) and low-load (20 RM) resistance training schemes on maximal strength and body composition. Sixteen resistance-trained men were randomly assigned to 1 of 2 groups: a moderate-load group (n = 8) or a low-load group (n = 8). The resistance training schemes consisted of 8 exercises performed 4 times per week for 6 weeks. In order to equate the number of repetitions performed by each group, the moderate load group performed 6 sets of 10 RM, while the low load group performed 3 sets of 20 RM. …

A Systematic Review, Meta-Analysis And Metaregression Of The Effect Of Protein Supplementation On Resistance Training-Induced Gains In Muscle Mass And Strength In Healthy Adults, Robert W. Morton, Kevin T. Murphy, Sean R. Mckellar, Brad J. Schoenfeld, Menno Henselmans, Eric Helms, Alan A. Aragon, Michaela C. Devries, Laura Banfield, James W. Krieger, Stuart M. Phillips

Publications and Research

Objective We performed a systematic review, metaanalysis and meta-regression to determine if dietary protein supplementation augments resistance exercise training (RET)-induced gains in muscle mass and strength.

Data sources A systematic search of Medline, Embase, CINAHL and SportDiscus.

Eligibility criteria Only randomised controlled trials with RET ≥6 weeks in duration and dietary protein supplementation.

Design Random-effects meta-analyses and metaregressions with four a priori determined covariates. Twophase break point analysis was used to determine the relationship between total protein intake and changes in fat-free mass (FFM).

ResultsData from 49 studies with 1863 participants showed that dietary protein supplementation significantly (all p …

International Society Of Sports Nutrition Position Stand: Diets And Body Composition, Alan A. Aragon, Brad J. Schoenfeld, Robert Wildman, Susan Kleiner, Trisha Vandusseldorp, Lem Taylor, Conrad P. Earnest, Paul J. Arciero, Colin Wilborn, Douglas S. Kalman, Jeffrey R. Stout, Darryn S. Willoughby, Bill Campbell, Shawn M. Arent, Laurent Bannock, Abbie E. Smith-Ryan, Jose Antonio

Publications and Research

Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature regarding the effects of diet types (macronutrient composition; eating styles) and their influence on body composition. The ISSN has concluded the following. 1) There is a multitude of diet types and eating styles, whereby numerous subtypes fall under each major dietary archetype. 2) All body composition assessment methods have strengths and limitations. 3) Diets primarily focused on fat loss are driven by a sustained caloric deficit. The higher the baseline body fat level, the more aggressively the caloric deficit …

Transcranial Direct Current Stimulation And Sports Performance, Dylan J. Edwards, Mar Cortes, Susan Wortman-Jutt, David Putrino, Marom Bikson, Gary Thickbroom, Alvaro Pascual-Leone

Publications and Research

No abstract provided.

Pre- Versus Post-Exercise Protein Intake Has Similar Effects On Muscular Adaptations, Brad J. Schoenfeld, Alan A. Aragon, Colin Wilborn, Stacie L. Urbina, Sara E. Hayward, James Kriegor

Publications and Research

The purpose of this study was to test the anabolic window theory by investigating muscle strength, hypertrophy, and body composition changes in response to an equal dose of protein consumed either immediately pre- versus post-resistance training (RT) in trained men. Subjects were 21 resistance-trained men (>1 year RT experience) recruited from a university population. After baseline testing, participants were randomly assigned to 1 of 2 experimental groups: a group that consumed a supplement containing 25 g protein and 1 g carbohydrate immediately prior to exercise (PRE-SUPP) (nD9) or a group that consumed the same supplement immediately post-exercise (POST- SUPP) …

Muscle Activation Differs Between Three Different Knee Joint-Angle Positions During A Maximal Isometric Back Squat Exercise, Paulo Henrique Marchetti, Josinaldo Jarbas Da Silva, Brad J. Schoenfeld, Priscyla Silva Monteiro Nardi, Silvio Luis Pecoraro, Julia Maria D'Andrea Greve, Erin Hartigan

Publications and Research

The purpose of this study was to compare muscle activation of the lower limb muscles when performing a maximal isometric back squat exercise over three different positions. Fifteen young, healthy, resistance-trained men performed an isometric back squat at three knee joint angles (20∘, 90∘, and 140∘) in a randomized, counterbalanced fashion. Surface electromyography was used to measure muscle activation of the vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF), biceps femoris (BF), semitendinosus (ST), and gluteusmaximus (GM). In general,muscle activity was the highest at 90∘ for the three quadricepsmuscles, yet differences in muscle activation between knee angles were muscle …

The Data Do Not Seem To Support A Benefit To Bcaa Supplementation During Periods Of Caloric Restriction, Brad P. Dieter, Brad Jon Schoenfeld, Alan A. Aragon

Publications and Research

J Int Soc Sports Nutr 13:1-015-0112-9, 2016 describe the efficacy of branched chain amino acid (BCAA) supplementation and resistance training for maintaining lean body mass during a calorie-restricted diet, and claim that this occurs with concurrent losses in fat mass. However, the reported results appear to be at odds with the data presented on changes in fat mass. This letter discusses the issues with the paper.

A Comparison Of Increases In Volume Load Over 8 Weeks Of Low-Versus High-Load Resistance Training, Brad J. Schoenfeld, Dan Ogborn, Bret Contreras, Tom Cappaert, Alex Silva Ribeiro, Brent A. Alvar, Andrew D. Vigotsky

Publications and Research

Background: It has been hypothesized that the ability to increase volume load (VL) via a progressive increase in the magnitude of load for a given exercise within a given repetition range could enhance the adaptive response to resistance training.

Objectives: The purpose of this study was to compare changes in volume load (VL) over eight weeks of resistance training (RT) in high-versus low-load protocols.

Materials and Methods: Eighteen well-trained men were matched according to baseline strength were randomly assigned to either a low-load RT(LOW,n= 9) where 25 - 35 repetitions were performed per exercise, or a high-load RT (HIGH,n= 9) …