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Effects Of Plyometric- And Cycle-Based High-Intensity Interval Training On Body Composition, Aerobic Capacity, And Muscle Function In Young Females: A Field-Based Group Fitness Assessment, A. J. Holmes, M. T. Stratton, A. R. Bailly, J. S. Gottschall, Y. Feito, P. L. Ha, A. Lavigne, K. Persaud, H. L. Gagnon, A. Krueger, A. Modjeski, T. A. Esmat, L. N. Harper, T. A. Vandusseldorp, Garrett Hester Aug 2023

Effects Of Plyometric- And Cycle-Based High-Intensity Interval Training On Body Composition, Aerobic Capacity, And Muscle Function In Young Females: A Field-Based Group Fitness Assessment, A. J. Holmes, M. T. Stratton, A. R. Bailly, J. S. Gottschall, Y. Feito, P. L. Ha, A. Lavigne, K. Persaud, H. L. Gagnon, A. Krueger, A. Modjeski, T. A. Esmat, L. N. Harper, T. A. Vandusseldorp, Garrett Hester

Faculty and Research Publications

High-intensity interval training (HIIT) is an effective alternative to moderate intensity continuous training for improvements in body composition and aerobic capacity; however, there is little work comparing different modalities of HIIT. The purpose of this study was to compare the effects of plyometric- (PLYO) and cycle-oriented (CYC) HIIT on body composition, aerobic capacity, and skeletal muscle size, quality, and function in recreationally trained females. Young (21.7 ± 3.1 yrs), recreationally active females were quasi-randomized (1:1 ratio) to 8 weeks of twice weekly PLYO (n = 15) or CYC (n = 15) HIIT. Body composition (four-compartment model), VO2peak …


Effects Of Creatine Monohydrate Timing On Resistance Training Adaptations And Body Composition After 8 Weeks In Male And Female Collegiate Athletes, Nicholas E. Dinan, Anthony Hagele, Andrew R. Jagim, Michael G. Miller, Chad M. Kerksick Nov 2022

Effects Of Creatine Monohydrate Timing On Resistance Training Adaptations And Body Composition After 8 Weeks In Male And Female Collegiate Athletes, Nicholas E. Dinan, Anthony Hagele, Andrew R. Jagim, Michael G. Miller, Chad M. Kerksick

Faculty Scholarship

Background: Limited research is available on the potential impact of creatine monohydrate administration before or after workouts among athletes. This study aimed to investigate the effects of pre- vs. post-exercise creatine monohydrate supplementation on resistance training adaptations and body composition.

Methods: In a randomized, double-blind, placebo-controlled, parallel design, 34 healthy resistance-trained male and female athletes were randomly assigned and matched according to fat free mass to consume a placebo, or 5-g dose of creatine monohydrate within 1 h before training, or within 1 h after training for 8 weeks, while completing a weekly resistance training program. Participants co-ingested 25-gram doses …


Acute And Chronic Bone Marker And Endocrine Responses To Resistance Exercise With And Without Blood Flow Restriction In Young Men, Debra A. Bemben, Vanessa D. Sherk, Samuel R. Buchanan, Sojung Kim, Kyle Sherk, Michael G. Bemben Mar 2022

Acute And Chronic Bone Marker And Endocrine Responses To Resistance Exercise With And Without Blood Flow Restriction In Young Men, Debra A. Bemben, Vanessa D. Sherk, Samuel R. Buchanan, Sojung Kim, Kyle Sherk, Michael G. Bemben

Health & Human Performance Faculty Publications and Presentations

In this study, we compared acute and chronic bone marker and hormone responses to 6 weeks of low intensity (20% 1RM) blood flow restriction (BFR20) resistance training to high intensity (70% 1RM) traditional resistance training (TR70) and moderate intensity (45% 1RM) traditional resistance training (TR45) in young men (18–35 years). Participants were randomized to one of the training groups or to a control group (CON). The following training programs were performed 3 days per week for 6 weeks for knee extension and knee flexion exercises: BFR20, 20%1RM, 4 sets (30, 15, 15, 15 reps) wearing blood flow restriction cuffs around …


Muscle Performance Changes With Age In Active Women, Ryan M. Miller, Eduardo D. S. Freitas, Aaron D. Heishman, Keldon M. Peak, Samuel R. Buchanan, J. Mikhail Kellawan, Hugo M. Pereira, Debra A. Bemben, Michael G. Bemben Apr 2021

Muscle Performance Changes With Age In Active Women, Ryan M. Miller, Eduardo D. S. Freitas, Aaron D. Heishman, Keldon M. Peak, Samuel R. Buchanan, J. Mikhail Kellawan, Hugo M. Pereira, Debra A. Bemben, Michael G. Bemben

Health & Human Performance Faculty Publications and Presentations

The purpose of this study was to examine age-related differences in muscle performance in women divided into young (YW, 20–39 years, n = 29) middle-aged (MAW, 40–59 years, n = 33), and older (OW, ≥60 years, n = 40) age groups. Methods: Hand grip strength, vertical jump performance, and knee extensor (KE) strength (0 deg/s, 60 deg/s, and 240 deg/s), speed of movement (SoM; at 1 Nm, 20%, 40%, and 60% isometric strength), and endurance (30-repetition test at 60 degs/s and 240 deg/s) were assessed. Computed tomography-acquired muscle cross-sectional area (mCSA) was measured and included to determine specific strength (KE …


When Task Constraints Delimit Movement Strategy: Implications For Isolated Joint Training In Dancers, Paige E. Rice, Sophia Nimphius Jan 2020

When Task Constraints Delimit Movement Strategy: Implications For Isolated Joint Training In Dancers, Paige E. Rice, Sophia Nimphius

Research outputs 2014 to 2021

Athletic performance is determined by numerous variables that cannot always be controlled or modified. Due to aesthetic requirements during sports such as dance, body alignment constrains possible movement solutions. Increased power transference around the ankle-joint, coupled with lower hip-joint power, has become a preferential strategy in dancers during leaps and may be considered a dance-specific stretch-shortening cycle (SSC) demand. Newell's theoretical model of interacting constraints includes organismic (or individual), environmental, and task constraints describing the different endogenous and exogenous constraints individuals must overcome for movement and athletic performance. The unique task constraints imposed during dance will be used as a …


Implementing Eccentric Resistance Training—Part 2: Practical Recommendations, Timothy J. Suchomel, John P. Wagle, Jamie Douglas, Christopher Taber, Melissa Harden, G. Gregory Haff, Michael H. Stone Aug 2019

Implementing Eccentric Resistance Training—Part 2: Practical Recommendations, Timothy J. Suchomel, John P. Wagle, Jamie Douglas, Christopher Taber, Melissa Harden, G. Gregory Haff, Michael H. Stone

Exercise Science Faculty Publications

The purpose of this review is to provide strength and conditioning practitioners with recommendations on how best to implement tempo eccentric training (TEMPO), flywheel inertial training (FIT), accentuated eccentric loading (AEL), and plyometric training (PT) into resistance training programs that seek to improve an athlete’s hypertrophy, strength, and power output. Based on the existing literature, TEMPO may be best implemented with weaker athletes to benefit positional strength and hypertrophy due to the time under tension. FIT may provide an effective hypertrophy, strength, and power stimulus for untrained and weaker individuals; however, stronger individuals may not receive the same eccentric (ECC) …


Skeletal Muscle Fiber Adaptations Following Resistance Training Using Repetition Maximums Or Relative Intensity, Kevin M. Carroll, Caleb D. Bazyler, Jake R. Bernards, Christopher Taber, Charles A. Stuart, Brad H. Deweese, Kimitake Sato, Michael H. Stone Jul 2019

Skeletal Muscle Fiber Adaptations Following Resistance Training Using Repetition Maximums Or Relative Intensity, Kevin M. Carroll, Caleb D. Bazyler, Jake R. Bernards, Christopher Taber, Charles A. Stuart, Brad H. Deweese, Kimitake Sato, Michael H. Stone

Exercise Science Faculty Publications

The purpose of the study was to compare the physiological responses of skeletal muscle to a resistance training (RT) program using repetition maximum (RM) or relative intensity (RISR). Fifteen well-trained males underwent RT 3 d·wk−1 for 10 weeks in either an RM group (n = 8) or RISR group (n = 7). The RM group achieved a relative maximum each day, while the RISR group trained based on percentages. The RM group exercised until muscular failure on each exercise, while the RISR group did not reach muscular failure throughout the intervention. Percutaneous needle biopsies of the vastus lateralis were obtained …


Common Habits, Adverse Events, And Opinions Regarding Pre-Workout Supplement Use Among Regular Consumers, Andrew R. Jagim, Clayton L. Camic, Patrick S. Harty Apr 2019

Common Habits, Adverse Events, And Opinions Regarding Pre-Workout Supplement Use Among Regular Consumers, Andrew R. Jagim, Clayton L. Camic, Patrick S. Harty

Faculty Scholarship

The purpose of the present study was to examine characteristics of multi-ingredient pre-workout supplement (MIPS) users, their common patterns/habits of MIPS ingestion, and their associated feelings about the effectiveness and safety of this class of supplements. An online electronic survey was distributed through social media to assess self-reported supplementation practices and preferences among adult males and females who reported regular MIPS use. A total of 1045 individuals responded, with 872 of these individuals (males: n = 636, 72.9%; females: n = 233, 26.7%; mean ± SD; age = 27.7 ± 7.9 years; training age = 8.2 ± 7.3 years) completing …


Common Ingredient Profiles Of Multi-Ingredient Pre-Workout Supplements, Andrew R. Jagim, Patrick S. Harty, Clayton L, Camic Jan 2019

Common Ingredient Profiles Of Multi-Ingredient Pre-Workout Supplements, Andrew R. Jagim, Patrick S. Harty, Clayton L, Camic

Faculty Scholarship

Multi-ingredient pre-workout supplements are a popular class of dietary supplements which are purported to improve exercise performance. However, the composition of these products varies substantially between formulations, thus making comparisons challenging. Therefore, the purpose of this study was to identify a common ingredient profile of top-selling pre-workout supplements and to compare ingredient dosages to established efficacious values. The top 100 commercially available pre-workout products were analyzed for listed ingredients and amounts, if available, from the supplement facts panel. The mean ± SD number of ingredients per supplement (n = 100) was 18.4 ± 9.7 with 8.1 ± 9.9 of these …


Effects Of An Aqueous Extract Of Withania Somnifera On Strength Training Adaptations And Recovery: The Star Trial, Tim N. Ziegenfuss, Anurag W. Kedia, Jennifer E. Sandrock, Betsy J. Raub, Chad M. Kerksick, Hector L. Lopez Nov 2018

Effects Of An Aqueous Extract Of Withania Somnifera On Strength Training Adaptations And Recovery: The Star Trial, Tim N. Ziegenfuss, Anurag W. Kedia, Jennifer E. Sandrock, Betsy J. Raub, Chad M. Kerksick, Hector L. Lopez

Faculty Scholarship

Withania somnifera (Ashwagandha) is an Ayurvedic herb categorized as having “rasayana” (rejuvenator), longevity, and revitalizing properties. Sensoril® is a standardized aqueous extract of the roots and leaves of Withania somnifera. Purpose: To examine the impact of Sensoril® supplementation on strength training adaptations. Methods: Recreationally active men (26.5 ± 6.4 years, 181 ± 6.8 cm, 86.9 ± 12.5 kg, 24.5 ± 6.6% fat) were randomized in a double-blind fashion to placebo (PLA, n = 19) or 500 mg/d Sensoril® (S500, n = 19). Body composition (DEXA), muscular strength, power, and endurance, 7.5 km cycling time trial, and clinical blood …


Multi-Ingredient Pre-Workout Supplements, Safety Implications, And Performance Outcomes: A Brief Review, Patrick S. Harty, Hannah A. Zabriskie, Jacob L. Erickson, Paul E. Molling, Chad M. Kerksick, Andrew R. Jagim Aug 2018

Multi-Ingredient Pre-Workout Supplements, Safety Implications, And Performance Outcomes: A Brief Review, Patrick S. Harty, Hannah A. Zabriskie, Jacob L. Erickson, Paul E. Molling, Chad M. Kerksick, Andrew R. Jagim

Faculty Scholarship

In recent years, a new class of dietary supplements called multi-ingredient pre-workout supplements (MIPS) has increased in popularity. These supplements are intended to be taken prior to exercise and typically contain a blend of ingredients such as caffeine, creatine, beta-alanine, amino acids, and nitric oxide agents, the combination of which may elicit a synergistic effect on acute exercise performance and subsequent training adaptations compared to single ingredients alone. Therefore, the purpose of this article was to review the theoretical rationale and available scientific evidence assessing the potential ergogenic value of acute and chronic ingestion of MIPS, to address potential safety …


Issn Exercise & Sports Nutrition Review Update: Research & Recommendations, Chad M. Kerksick, Colin D. Wilborn, Michael D. Roberts, Abbie Smith-Ryan, Susan M. Kleiner, Ralf Jäger, Rick Collins, Matthew Cooke, Jaci N. Davis, Elfego Galvan, Mike Greenwood, Lonnie M. Lowery, Robert Wildman, Jose Antonio, Richard B. Kreider Aug 2018

Issn Exercise & Sports Nutrition Review Update: Research & Recommendations, Chad M. Kerksick, Colin D. Wilborn, Michael D. Roberts, Abbie Smith-Ryan, Susan M. Kleiner, Ralf Jäger, Rick Collins, Matthew Cooke, Jaci N. Davis, Elfego Galvan, Mike Greenwood, Lonnie M. Lowery, Robert Wildman, Jose Antonio, Richard B. Kreider

Faculty Scholarship

Background

Sports nutrition is a constantly evolving field with hundreds of research papers published annually. In the year 2017 alone, 2082 articles were published under the key words ‘sport nutrition’. Consequently, staying current with the relevant literature is often difficult.

Methods

This paper is an ongoing update of the sports nutrition review article originally published as the lead paper to launch the Journal of the International Society of Sports Nutrition in 2004 and updated in 2010. It presents a well-referenced overview of the current state of the science related to optimization of training and performance enhancement through exercise training and …


Repetition-To-Repetition Differences Using Cluster And Accentuated Eccentric Loading In The Back Squat, John P. Wagle, Christopher B. Taber, Aaron J. Cunanan, Matt L. Sams, Alexander Wetmore, Garett E. Bingham, Brad H. Deweese, Kimitake Sato, Charles A. Stuart, Michael H. Stone Jul 2018

Repetition-To-Repetition Differences Using Cluster And Accentuated Eccentric Loading In The Back Squat, John P. Wagle, Christopher B. Taber, Aaron J. Cunanan, Matt L. Sams, Alexander Wetmore, Garett E. Bingham, Brad H. Deweese, Kimitake Sato, Charles A. Stuart, Michael H. Stone

Exercise Science Faculty Publications

The current investigation was an examination of the repetition-to-repetition magnitudes and changes in kinetic and kinematic characteristics of the back squat using accentuated eccentric loading (AEL) and cluster sets. Trained male subjects (age = 26.1 ± 4.1 years, height = 183.5 ± 4.3 cm, body mass = 92.5 ± 10.5 kg, back squat to body mass ratio = 1.8 ± 0.3) completed four load condition sessions, each consisting of three sets of five repetitions of either traditionally loaded straight sets (TL), traditionally loaded cluster sets (TLC), AEL cluster sets (AEC), and AEL straight sets where only the initial repetition had …


Methods Matter: The Relationship Between Strength And Hypertrophy Depends On Methods Of Measurement And Analysis, Andrew D. Vigotsky, Brad J. Schoenfeld, Christian Than, J. Mark Brown Jun 2018

Methods Matter: The Relationship Between Strength And Hypertrophy Depends On Methods Of Measurement And Analysis, Andrew D. Vigotsky, Brad J. Schoenfeld, Christian Than, J. Mark Brown

Publications and Research

Purpose: The relationship between changes in muscle size and strength may be affected by both measurement and statistical approaches, but their effects have not been fully considered or quantified. Therefore, the purpose of this investigation was to explore how different methods of measurement and analysis can affect inferences surrounding the relationship between hypertrophy and strength gain.

Methods: Data from a previous study—in which participants performed eight weeks of elbow flexor training, followed by an eight-week period of detraining—were reanalyzed using different statistical models, including standard between-subject correlations, analysis of covariance, and hierarchical linear modeling.

Results: The associative relationship between strength …


Force-Time Differences Between Ballistic And Non-Ballistic Half-Squats., Timothy J. Suchomel, Christopher Taber, Christopher J. Sole, Michael Henry Stone Jan 2018

Force-Time Differences Between Ballistic And Non-Ballistic Half-Squats., Timothy J. Suchomel, Christopher Taber, Christopher J. Sole, Michael Henry Stone

Exercise Science Faculty Publications

The purpose of this study was to examine the force-time differences between concentric-only half-squats (COHS) performed with ballistic (BAL) or non-ballistic (NBAL) intent across a range of loads. Eighteen resistance-trained men performed either BAL or NBAL COHS at 30%, 50%, 70%, and 90% of their one repetition maximum (1RM) COHS. Relative peak force (PF) and relative impulse from 0⁻50 ms (Imp50), 0⁻90 ms (Imp90), 0⁻200 ms (Imp200), and 0⁻250 ms (Imp250) were compared using a series of 2 × 4 (intent × load) repeated measures ANOVAs with Bonferroni post hoc tests. Cohen's d effect sizes were calculated to provide measures …


Effectiveness Of Tai Chi On Cardiac Autonomic Function And Symptomatology In Women With Fibromyalgia: A Randomized Controlled Trial, Alexei Wong, Arturo Figueroa, Marcos A. Sanchez-Gonzalez, Won-Mok Son, Oksana P. Chernykh, Song-Young Park Jan 2018

Effectiveness Of Tai Chi On Cardiac Autonomic Function And Symptomatology In Women With Fibromyalgia: A Randomized Controlled Trial, Alexei Wong, Arturo Figueroa, Marcos A. Sanchez-Gonzalez, Won-Mok Son, Oksana P. Chernykh, Song-Young Park

Health and Kinesiology Faculty Publications

The present study examined the effects of a 12-week Tai Chi (TC) training regimen on heart rate variability (HRV), symptomatology, muscle fitness and body composition in women with fibromyalgia. Participants were randomly assigned to either a TC training group (n = 18) or a control group (n = 19). HRV, symptomatology, muscle fitness and body composition were measured before and after 12 weeks. There were significant decreases (p < 0.05) in sympathovagal balance (LnLF/LnHF), sympathetic tone (LnLF, nLF), pain, and fatigue, and significant increases (p < 0.05) in parasympathetic tone (LnHF, nHF), strength and flexibility following TC compared with no changes after control. The changes in LnLF and LnLF/LnHF were correlated with changes in pain. There were no significant changes in HR, sleep quality and body composition after TC or control. TC may be an effective therapeutic intervention for improving sympathovagal balance, pain, fatigue, strength and flexibility in women with fibromyalgia.


Musculoskeletal Outcomes From Chronic High-Speed, High-Impulse Resistance Exercise, John Francis Caruso, Michael Voor, Jason R. Jaggers, T. B. Symons, Jeremy Stith, Ling Bai, Ema Selimovic, Kathy Carter, Jennifer Daily Jan 2018

Musculoskeletal Outcomes From Chronic High-Speed, High-Impulse Resistance Exercise, John Francis Caruso, Michael Voor, Jason R. Jaggers, T. B. Symons, Jeremy Stith, Ling Bai, Ema Selimovic, Kathy Carter, Jennifer Daily

Faculty Scholarship

While bones and muscles adapt to mechanical loading, it appears that very specific types of stimuli must be applied to achieve osteogenesis. Our study assessed musculoskeletal outcomes to 30 training sessions on an Inertial Exercise Trainer (Newnan, GA). Subjects (n = 13) performed workouts with their left leg, while their right served as an untreated control. Work-outs entailed three 60-s sets each of knee extension, hip extension and calf press exercises, separated by 90-s rests. Before and after the 30 training sessions, subjects underwent strength tests (knee and ankle extensors of both legs), DEXA scans (hip, knee and ankles of …


Comparison Of The Relationship Between Lying And Standing Ultrasonography Measures Of Muscle Morphology With Isometric And Dynamic Force Production Capabilities, John P. Wagle, Kevin M. Carroll, Aaron J. Cunanan, Christopher B. Taber, Alexander Wetmore, Garett E. Bingham, Brad H. Deweese, Kimitake Sato, Charles A. Stuart, Michael H. Stone Dec 2017

Comparison Of The Relationship Between Lying And Standing Ultrasonography Measures Of Muscle Morphology With Isometric And Dynamic Force Production Capabilities, John P. Wagle, Kevin M. Carroll, Aaron J. Cunanan, Christopher B. Taber, Alexander Wetmore, Garett E. Bingham, Brad H. Deweese, Kimitake Sato, Charles A. Stuart, Michael H. Stone

Exercise Science Faculty Publications

The purpose of the current study was (1) to examine the differences between standing and lying measures of vastus lateralis (VL), muscle thickness (MT), pennation angle (PA), and cross-sectional area (CSA) using ultrasonography; and (2) to explore the relationships between lying and standing measures with isometric and dynamic assessments of force production—specifically peak force, rate of force development (RFD), impulse, and one-repetition maximum back squat. Fourteen resistance-trained subjects (age = 26.8 ± 4.0 years, height = 181.4 ± 6.0 cm, body mass = 89.8 ± 10.7 kg, back squat to body mass ratio = 1.84 ± 0.34) agreed to participate. …


The Aging Neuromuscular System And Motor Performance, Sandra K. Hunter, Hugo M. Pereira, Kevin Keenan Oct 2016

The Aging Neuromuscular System And Motor Performance, Sandra K. Hunter, Hugo M. Pereira, Kevin Keenan

Exercise Science Faculty Research and Publications

Age-related changes in the basic functional unit of the neuromuscular system, the motor unit, and its neural inputs have a profound effect on motor function, especially among the expanding number of old (older than ∼60 yr) and very old (older than ∼80 yr) adults. This review presents evidence that age-related changes in motor unit morphology and properties lead to impaired motor performance that includes 1) reduced maximal strength and power, slower contractile velocity, and increased fatigability; and 2) increased variability during and between motor tasks, including decreased force steadiness and increased variability of contraction velocity and torque over …


Effects Of Different Rest Intervals Between Antagonist Paired Sets On Repetition Performance And Muscle Activation, Mariana F. Maia, Jeffrey M. Willardson, Gabriel A. Paz, Humberto Miranda Sep 2014

Effects Of Different Rest Intervals Between Antagonist Paired Sets On Repetition Performance And Muscle Activation, Mariana F. Maia, Jeffrey M. Willardson, Gabriel A. Paz, Humberto Miranda

Faculty Research and Creative Activity

Effects

of different rest intervals between antagonist paired sets on

repetition performance and muscle activation. J Strength

Cond Res 28(9): 2529–2535, 2014—Recent evidence

suggests that exercising the antagonist musculature acutely

enhances subsequent performance for the agonist musculature.

The purpose of this study was to examine the effects of

different rest intervals between sets for exercises that involve

antagonistic muscle groups, a technique referred to as

antagonist paired sets (APS). Fifteen recreationally trained

men were tested for knee extension (KE) exercise performance,

with or without previous knee flexion (KF) exercise

for the antagonist musculature. The following protocols were

performed in random …


Lower Extremity Injury In Female Basketball Players Is Related To A Large Difference In Peak Eversion Torque Between Barefoot And Shod Conditions, Jenna M. Yentes, Max J. Kurz, Nikolaos Stergiou Sep 2014

Lower Extremity Injury In Female Basketball Players Is Related To A Large Difference In Peak Eversion Torque Between Barefoot And Shod Conditions, Jenna M. Yentes, Max J. Kurz, Nikolaos Stergiou

Journal Articles

Background
The majority of injuries reported in female basketball players are ankle sprains and mechanisms leading to injury have been debated. Investigations into muscular imbalances in barefoot versus shod conditions and their relationship with injury severity have not been performed. The purpose of this study was to investigate the effects of wearing athletic shoes on muscular strength and its relationship to lower extremity injuries, specifically female basketball players due to the high incidence of ankle injuries in this population.

Methods
During pre-season, 11 female collegiate basketball players underwent inversion and eversion muscle strength testing using an isokinetic dynamometer in both …


Leg Strength And Lean Mass Symmetry Influences Kicking Performance In Australian Football, Nicolas H. Hart, Sophia Nimphius, Tania Spiteri, Robert U. Newton Jan 2014

Leg Strength And Lean Mass Symmetry Influences Kicking Performance In Australian Football, Nicolas H. Hart, Sophia Nimphius, Tania Spiteri, Robert U. Newton

Research outputs 2014 to 2021

Differential loading patterns during game-based participation may produce or exacerbate strength imbalances between the lower limbs. It is currently unknown whether such imbalances are functionally beneficial or detrimental to performance. This study assessed the influence of lower limb strength and lean mass symmetry on kicking accuracy in Australian Football. Thirty-one Australian footballers were required to perform a kicking assessment, producing ten drop punt kicks over twenty metres to a player target. Athletes were subsequently separated into accurate (n = 15) and inaccurate (n = 16) groups, with lower-body lean mass assessed using whole body DXA scans, and lower-body strength assessed …


Effects Of Different Antagonist Protocols On Repetition Performance And Muscle Activation, Andrade Paz, Jeffrey Willardson, Roberto Simao, Humberto Miranda Jan 2013

Effects Of Different Antagonist Protocols On Repetition Performance And Muscle Activation, Andrade Paz, Jeffrey Willardson, Roberto Simao, Humberto Miranda

Faculty Research and Creative Activity

Objective: To investigate the acute effects of different antagonist manipulation protocols on maximal repetition performance and muscle activation during seated row (SR) exercise.

Methods: Fifteen men (22.4 ± 1.1 years old, height 175 cm ± 5.5, weight 76.6 kg ± 7, and 12.3 ± 2.1 of body fat percentage) with previous resistance training experience (3.5 ± 1.2 years) performed four experimental protocols: (TP) one set to repetition failure of SR exercise; (AS) Antagonist static stretching for the pectoralis major (PM) followed by one set of SR; (PNFA) Proprioceptive neuromuscular facilitation for PM followed by one set of the SR; (APS) …


Exercise And Blood Flow Restriction, Zachary K. Pope, Jeffrey Willardson, Brad J. Schoenfeld Jan 2013

Exercise And Blood Flow Restriction, Zachary K. Pope, Jeffrey Willardson, Brad J. Schoenfeld

Faculty Research and Creative Activity

Pope, ZK, Willardson, JM, and Schoenfeld, BJ. Exercise and blood flow restriction. J Strength Cond Res 27(10): 2914– 2926, 2013—A growing body of research has demonstrated the effectiveness of exercise (low-intensity resistance training, walking, cycling) combined with blood flow restriction (BFR) for increased muscular strength and hypertrophy. The BFR is achieved via the application of external pressure over the proximal portion of the upper or lower extremities. The external pressure applied is sufficient to maintain arterial inflow while occluding venous outflow of blood distal to the occlusion site. With specific reference to low-intensity resistance training, the ability to significantly increase …


Endurance Tests Are The Most Reliable Core Stability Related Measurements, Andy Waldhelm, Li Li Sep 2012

Endurance Tests Are The Most Reliable Core Stability Related Measurements, Andy Waldhelm, Li Li

Department of Health Sciences and Kinesiology Faculty Publications

Purpose: To determine the intra-tester reliability of clinical measurements that assess five components related to core stability: strength, endurance, flexibility, motor control, and function. Methods: Participants were 15 college-aged males who had not suffered any orthopedic injury in the past year. Core strength measurements included eight isometric tests and a sit-up test. The four core endurance tests were the trunk flexor test, trunk extensor test, and bilateral side bridge tests. Flexibility tests included the sit-and-reach test and active range of the trunk and hip joint motions. Proprioception via passive reposition tests of the hips and a single limb balance test …


Comparing Thigh Muscle Cross-Sectional Area And Squat Strength Among National Class Olympic Weightlifters, Power Lifters, And Bodybuilders, James J. Di Naso, Brian L. Pritschet, John D. Emmett, Jill W. Owen, Jeffrey Willardson, Travis W. Beck, Jason M. Defreitas, Fabio E. Fontana Jun 2012

Comparing Thigh Muscle Cross-Sectional Area And Squat Strength Among National Class Olympic Weightlifters, Power Lifters, And Bodybuilders, James J. Di Naso, Brian L. Pritschet, John D. Emmett, Jill W. Owen, Jeffrey Willardson, Travis W. Beck, Jason M. Defreitas, Fabio E. Fontana

Faculty Research and Creative Activity

Few studies have compared anthropometric characteristics among national class athletes from different resistance training disciplines, such as Olympic Weightlifting (OL), Power Lifting (PL), and Bodybuilding (BB). Objective: The purpose of the current study was to determine if significant differences exist in the relationship between thigh muscle cross-sectional area and back squat strength among national class athletes from the sports of OL, PL, and BB. Methods: Fifteen national class athletes were assessed for back squat strength, mid-thigh circumference, and mid-thigh skinfold from which total thigh cross-sectional was estimated. A series of One-Way ANOVAs and Pearson Product Moment Correlations were used to …


Acute Effects Of Antagonist Stretching On Jump Height, Torque, And Electromyography Of Agonist Musculature, John B. Sandberg, Dale R. Wagner, Jeffrey Willardson, Gerald Aparecido Smith Jan 2012

Acute Effects Of Antagonist Stretching On Jump Height, Torque, And Electromyography Of Agonist Musculature, John B. Sandberg, Dale R. Wagner, Jeffrey Willardson, Gerald Aparecido Smith

Faculty Research and Creative Activity

Although there has been substantial research on the acute effects of static stretching on subsequent force and power development, the outcome after stretching of the antagonist musculature has not been examined. The purpose of this study was to investigate the effects of static stretching of antagonist musculature on multiple strength and power measures. Sixteen trained men were tested for vertical jump height and isokinetic peak torque production during knee extension at 60°.s (SlowKE) and 300°.s (FastKE). Electromyography was recorded for the vastus lateralis and the biceps femoris muscles during isokinetic knee extension. Subjects performed these tests in a randomized counterbalanced …


The Acute Time Course Of Concurrent Activation Potentiation, Luke Garceau, Erich Petushek, Mckenzie Fauth, William Ebben Jan 2010

The Acute Time Course Of Concurrent Activation Potentiation, Luke Garceau, Erich Petushek, Mckenzie Fauth, William Ebben

Exercise Science Faculty Research and Publications

This study evaluated the acute time course of the ergogenic effect of concurrent activation potentiation (CAP). Forty-two men and women, including CAP non-responders and responders, performed a 5 second isometric knee extension on a dynamometer with the use of remote voluntary contractions (RVC). Mean torque was assessed in seven 500 millisecond (ms) time periods. A two-way repeated measures ANOVA revealed significant main effects for time period (p ≤ 0.001), but no significant interaction between time period and CAP non-responders and responders (p > 0.05). The ergogenic effects of CAP are accrued during the first 1000ms. Concurrent activation potentiation responders produce greater …


The Effect Of Concurrent Activation Potentiation On The Knee Extensor And Flexor Performance Of Men And Women, Luke Garceau, Erich Petushek, Mckenzie Fauth, William Ebben Jan 2010

The Effect Of Concurrent Activation Potentiation On The Knee Extensor And Flexor Performance Of Men And Women, Luke Garceau, Erich Petushek, Mckenzie Fauth, William Ebben

Exercise Science Faculty Research and Publications

This study evaluated the effect of remote voluntary contractions (RVC) during isometric and isokinetic knee flexion and extension tests and evaluated gender differences therein. Subject peak torque, rate of torque development, and power were assessed with a dynamometer in RVC and no RVC’s conditions. A two way mixed ANOVA with repeated measures for condition was used to evaluate the interaction between conditions and gender, and to assess the main effects. Main effects were evaluated with a paired samples t-test. Results revealed a significant interaction between all but one test condition and gender as well as significant main effects for all …


Effect Of Rest Interval Length On The Volume Completed During Upper Body Resistance Exercise, Humberto Miranda, Roberto Simão, Leonardo Marmo Moreira, Renato Aparecido De Souza, João Antônio Alves De Souza, Belmiro Freitas De Salles, Jeffrey Willardson Jan 2009

Effect Of Rest Interval Length On The Volume Completed During Upper Body Resistance Exercise, Humberto Miranda, Roberto Simão, Leonardo Marmo Moreira, Renato Aparecido De Souza, João Antônio Alves De Souza, Belmiro Freitas De Salles, Jeffrey Willardson

Faculty Research and Creative Activity

The purpose of the current study was to compare the workout volume (sets x resistance x repetitions per set) completed during two upper body resistance exercise sessions that incorporated 1 minute versus 3 minute rest intervals between sets and exercises. Twelve trained men completed two experimental sessions that consisted of 5 upper body exercises (i.e. barbell bench press, incline barbell bench press, pec deck flye, barbell lying triceps extension, triceps pushdown) performed for three sets with an 8- RM load. The two experimental sessions differed only in the length of the rest interval between sets and exercises; one session with …